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PubMed1975

Dietary calcium levels in pre-lay and lay diets in Leghorn pullets.

Four experiments over a period of four years with 1350 first-year pullets were designed to determine the influence of the calcium and phosphorus levels in the pre-lay diets on the growing birds and on their subsequent performance. Several dietary calcium levels in the lay period were studied, as well as the interaction between the pre-lay and lay diets. During the growing phase the pullets fed 3.0% calcium and 0.4% phosphorus had significantly (P less than 0.05) lower body weight at 20 weeks of age than thep ulletsin the other pre-lay treatments. Feed consumption and feed efficiency were also adversely affected by this treatment, and sexual maturity was significantly (P less than 0.05) delayed. Early lay mortality from this treatment was evident. On the basis of egg production, egg weight, shell deformation and percent poorly shelled eggs (PSE) at point-of-lay, the pre-lay diets did not influence lay performance nor was there an interaction between any combination of pullet and lay diets. As the calcium levels of the lay diets increased, egg production, feed consumption and shell rigidity increased. The 1.5% calcium level did not maintain bone mineralization as compared to the 3.0 and 4.5% calcium levels. It was noted that shell quality on the basis of PSE and deformation does not begin to deteriorate immediately after the onset of production. In fact there is a short period of time where the egg shells improve and then there is a gradual decline in shell rigidity. The layers fed the lay diet containing 1.5% calcium produced eggs weighing an average of 57.4 g. This was significantly (P less than 0.05) lower than the eggs of the 2.3, 3.0 or 4.5% calcium fed groups which produced eggs weighing 59.1, 58.6 and 59.4 g. respectively.

Animal Feed↗
PubMed1985

Effects of dietary fat level on laying hens fed various concentrations of calcium.

The effects of supplementing laying hen diets with 0, 5, or 10% fat in the presence of 3.0, 3.6, or 4.2% dietary calcium was investigated using laying hens over a 7-week period. There was no significant effect of the fat or calcium treatments on laying hen performance as judged by feed intake, weight gain, egg production, egg weight, and egg shell deformation. Although there was an increase in fat retention with an increase in dietary fat level (P less than .01), a larger proportion (P less than .05) of unabsorbed fat was present as soap in the excreta of birds on these diets relative to those fed the control diet. There was evidence to indicate that most of the soap observed in the excreta of laying hens was formed in postabsorptive areas of the gut, thereby explaining why the detrimental effects of soap formation were not seen in the laying hen. Increasing the dietary calcium level reduced both percentage calcium (P less than .01) and magnesium (P less than .05) retention. There were no significant effects of the treatments on nitrogen and phosphorus retention. There were also no significant effects of the treatments on shell ash, shell calcium, magnesium, and phosphorus content. Increasing the dietary calcium level increased bone ash (P less than .05) while reducing bone magnesium content (P less than .05). There were no significant effects of the fat and calcium treatments on bone calcium and phosphorus content.

Animals↗
PubMed1999

[Community emergency medical service. Epidemiology and quality of treatment in a rural district].

OBJECTIVES: Rapid aid provided by lay witnesses and emergency services can improve the outcome in medical emergencies arising in the community. We attempted to study the quality of first aid rendered by lay persons, paramedical personnel, and community medical practitioners attending out-of-hospital emergencies. We also evaluated the frequency of first aid provided before the arrival of specialised emergency physicians. METHODS: Over a period of six months all emergencies in a rural district of Germany leading to the pre-hospital medical service being dispatched were studied. Specialised community emergency physicians arriving at the site of the event recorded demographic, clinical, and process data using a standardised instrument. They also assessed the performance of lay persons, paramedical personnel, and community physicians providing immediate care. Implicit and explicit criteria were used. RESULTS: In 97% of cases analysed (n = 1150) members of the above mentioned groups were present before the arrival of the dedicated medical service. Lay persons were judged to provide inadequate care especially with regard to airway management and immobilisation of suspected fractures. For paramedical personnel, the administration of medication, venous lines and immobilisation turned out to be problematic areas. Medical practitioners fell below the defined standards especially in airway management, immobilisation and venous lines. CONCLUSION: Our project has shown how important the evaluated groups are for community emergency care. Despite methodological problems in this area of study, the shortcomings demonstrated may be targeted by future training at different levels.

Emergency Medical Services↗
PubMed1996

Homing in on the homeless: assessing the physical health of homeless adults in Los Angeles County using an original method to obtain physical examination data in a survey.

OBJECTIVE: Public policy that decreases the finding for social services may combine with the ascendancy of corporate managed care to increase the health care deficit. Assessing the health impact of these policy changes on various populations is a fundamental challenge for health services research. Disadvantaged populations, such as the homeless, are likely to be affected disproportionately. Research quality data on the physical health of such populations are difficult and expensive to obtain. In particular, physical examination data have not been available and self-reports are insufficient. Our objective: to develop and utilize a structured physical exam system enabling lay survey researchers to report reliably physical findings related to six tracer conditions in a disadvantaged population. STUDY SETTING: A field survey of homeless adults in Los Angeles County, California. Respondents were 363 homeless adults representing a subsample of a probability sample of the county's homeless adult population. STUDY DESIGN: We integrated existing measures with expert clinical opinion and original means of data collection into a structured physical exam enabling lay interviewers to identify the prevalence of vision problems, significant skin disorders, peripheral vascular disease of the lower extremities, selected podiatric disorders, hypertension, and tuberculosis in a sample of homeless adults. PRINCIPAL MEASURES: We describe lay interviewer performance in terms of mastery of the necessary material based on written and practical exams and in terms of the number of respondents successfully followed. We base our description of the instrument on the time necessary to complete it, and on the proportion of each component successfully completed during the field survey, as well as on interrater reliability. We report the prevalence of the various clinical conditions according to self-report and according to the structured limited physical exam, as well as the marginal proportion of respondents who were identified by the physical exam and not by self-report. PRINCIPAL FINDINGS: Interviewers performed the exam successfully under field conditions. Respondent acceptance of the instrument was high. Interrater agreement was 100 percent regarding the need for referral on the basis of blood pressure and vision. Kappa statistics for skin, foot, and edema findings were .67,.71, and .81, respectively. Adjusted for sampling weights, 60 percent of this population required referral for at least one of the specified conditions. For those portions of the survey for which both self-report and physical exam data were available, lay interviewers made significant percentages of referrals on the basis of physical findings alone. CONCLUSIONS: High blood pressure, poor vision, peripheral vascular diseases of the feet and legs, and significant skin conditions are prevalent among the homeless in Los Angeles County. Without physical exam data, estimates of the prevalence of these conditions will be incorrect. Researchers can use laypersons to collect reliable and valid physical exam data on disadvantaged populations. This represents a new tool for assessing and monitoring the health of these populations.

Adult↗
PubMed2002

Effects of dietary chromium picolinate and ascorbic acid supplementation on egg production, egg quality and some serum metabolites of laying hens reared under a low ambient temperature (6 degrees C).

This experiment was conducted to evaluate the effects of chromium (chromium picolinate, Cr Pic) and vitamin C (L-ascorbic acid) supplementation on egg production and egg quality in laying hens (Hy-Line) kept at 18 degrees C (at thermo-neutral zone) or 6 degrees C (cold stress) in temperature-controlled rooms. One hundred and fifty laying hens (32 week-old) were divided into 5 groups, 30 hens per group. The laying hens kept at 6 degrees C temperature were fed either a basal diet (low temperature-basal diet, LTB group) or the basal diet supplemented with either 400 micrograms of Cr per kg diet (Cr group), 250 mg of L-ascorbic acid per kg diet (Vit C group) or 400 micrograms of Cr plus 250 mg of L-ascorbic acid per kg diet (Vit C + Cr group) while hens kept at 18 degrees C fed a basal diet (thermo-neutral-basal diet, TNB group). Performance and egg quality were significantly reduced in LTB group compared with TNB group. Supplemental chromium and vitamin C significantly increased live weight change, egg production, and improved feed efficiency in cold-stressed hens compared with group fed the basal diet at 6 degrees C brought up to the values of the group reared under thermoneutral conditions (18 degrees C). Egg production and egg weight were also greater in each supplemental group compared with the LTB group. Separately or as a combination, supplemental chromium and vitamin C increased serum insulin but decreased corticosterone, glucose and cholesterol concentrations. Results of the present study show that supplementing vitamin C and chromium, particularly as a combination, improved the performance of cold-stressed hens. Such a combination of supplement can offer a potential protective management practice in preventing cold stress-related losses in performance of laying hens.

Animals↗
PubMed1998

Further investigations on the effect of dietary manipulation of protein, phosphorus, and calcium for reducing their daily requirement for laying hens.

Experiments were conducted to determine the possibility of reducing the daily requirement of laying hens for Ca, available P (AP), and protein by providing the hens with adequate levels of these nutrients only during those hours of the day that the physiological need for these nutrients for formation of various components of the eggs are increasing. The results of the Ca experiment indicated that the daily Ca requirement cannot be reduced by providing the hens with adequate levels of Ca during the afternoon (1500 to 2100 h) and inadequate Ca level during the morning (0500 to 1500 h). Providing the hens with most of the daily Ca need during the afternoon did not have a beneficial effect on shell quality as compared to the control group that received a diet with 3.5% Ca during the morning and the afternoon. On the other hand, inadequate Ca intake during the afternoon adversely affected shell quality as compared to the control group (P < 0.05). The AP experiment indicated that egg production performance and shell quality can be maintained satisfactorily as long as the daily intake of AP is adequate, regardless of whether most of the AP is consumed during the morning or the afternoon. Egg production and shell quality of hens fed a diet with 0.4% AP during the morning and 0.1% AP during the afternoon or 0.1% AP during the morning and 0.4% AP during the afternoon were not different than the control group that received a diet with 0.25% AP during the morning and the afternoon. The results of two protein experiments failed to indicate that egg production performance of laying hens can be maintained satisfactorily by providing them with an adequate level of protein (16%) only during the morning and inadequate level of protein (10%) during the afternoon or, conversely, compared to the control group that received a diet with 16% protein both during the morning and afternoon (P < 0.05). The supply of adequate protein with sufficient amino acids, during the morning and the afternoon, was required for satisfactory maintaining egg production performance. Under the conditions selected for the conduct of this study, the results of the current experiments, combined with those of a previous report, failed to support the hypothesis that satisfactory performance may be maintained by providing the hens with adequate levels of protein, AP, and Ca only during those hours of the day when the physiological need for these nutrients for formation of various components of the egg are increasing.

Animal Feed↗
PubMed2004

Methods and demographic findings of the baseline survey of the NEDICES cohort: a door-to-door survey of neurological disorders in three communities from Central Spain.

OBJECTIVE: To describe the methods and general results of the baseline longitudinal survey in a defined cohort of elderly people from three areas of Central Spain (urban and rural). The survey was designed to study dementia, essential tremor, Parkinson's disease and stroke. STUDY DESIGN: A population-based longitudinal study with door-to-door interviews. METHODS: This study was carried out in two phases: Phase 1 (health status questionnaire and screening performed by lay interviewers) and Phase 2 (diagnosis of neurological illnesses by neurologists). RESULTS: The study flow chart, screening instruments for neurological disorders, main demographic data (age, sex, educational attainment, occupation) and general health status of the 5,278 screened participants (2,238 men and 3,040 women) are given for the two phases. The response rate was 85.3%, and participation was higher in men and in the urban area. CONCLUSIONS: Participation rates were good in both phases of the NEDICES baseline study, and this was influenced by age, sex and setting of the participants. Educational attainment, occupation and health status data are analogous to other Spanish studies performed in the elderly. As the study population was large and good participation rates were achieved, precise analysis of morbidity of the neurological disorders investigated will be possible.

Age Factors↗
PubMed1998

Theoretical calculation of maximum attainable benefit of public access defibrillation in Belgium. Belgian Cardio Pulmonary Cerebral Resuscitation Study Group.

OBJECTIVE: Assuming that a lay person performing cardiopulmonary resuscitation (CPR) will also use an automatic external defibrillator (AED) wherever available, we tried to estimate the maximal attainable benefit of public access defibrillation in some centres in Belgium. METHODS: We analysed retrospectively the data from the Belgian Cardio Pulmonary Cerebral Resuscitation Registry collected between 1991 and June 1996. The majority of these emergency medical service (EMS) systems are two-tiered with an early defibrillation program for the first tier and a physician-staffed second tier. RESULTS: The data show that, in 5543 registered cases, there were 1001 (18%) adults with non-traumatic ventricular fibrillation/ventricular tachycardia (VF/VT) as the first monitored rhythm. In this subgroup there were 419 (42%) cases who had lay CPR. The duration of lay CPR before the first defibrillation either by the first or the second tier is known in 357 cases. This duration was more than 5 min and 10 min, in 80% and 53% of the cases, respectively. The median (Q1, Q3) lay CPR duration was 11 (7, 15) min. Survival to hospital discharge in this subgroup was achieved in 80/357 (22%) patients. Using Weaver's linear model for survival after witnessed VF/VT, an estimated increase of more than 30% in survival rate was calculated. CONCLUSION: It is concluded that in our EMS system, laymen reach a substantial number of VF/VT victims many minutes before the arrival of the professional EMS teams. Therefore, a substantial increase in the number of survivors could be expected if lay responders were prepared to use an AED.

Aged↗
PubMed2005

Predictors of survival and hospital outcome of prehospital cardiac arrest in southern Taiwan.

BACKGROUND AND PURPOSE: Despite recent improvements in emergency care medicine, outcome for prehospital cardiac arrest patients remains poor in southern Taiwan due to lack of training and authorization of emergency medical technicians to perform advanced life support. The purpose of this study was to analyze the characteristics of these patients and to identify possible predictive factors for final hospital discharge. METHODS: We retrospectively reviewed the characteristics of 361 prehospital cardiac arrest patients (male:female, 226:135; median age, 69 years) undergoing cardiopulmonary resuscitation (CPR) on arrival at the emergency department (ED) between January 1, 2001 and December 31, 2003. Multivariate analysis was performed by fitting explanatory variables into logistic regression models with respect to the outcomes of admission and to hospital discharge. RESULTS: The overall survival rate was 21.1% (n = 76) to hospital admission and 7.2% (26) to hospital discharge. About half (54%) of the 26 patients who survived had cardiac disease. Only 3 patients received CPR from a bystander, and 2 of them survived. None of the patients received electrical defibrillation before arriving at hospital because emergency personnel were not authorized to perform advanced cardiac life support (ACLS) in Southern Taiwan during the study period. Factors that predicted survival to hospital discharge included a short interval between the cardiac arrest and arrival at the ED, initial rhythm of ventricular tachycardia/ventricular fibrillation (VT/VF), lower atropine dose, higher level of hemoglobin, less multiple organ failure, and shorter duration of resuscitation in the ED. Nine of the 32 patients (28%) with VT/VF survived compared with 5 of 49 (10%) with pulseless electrical activity and only 12 of 231 (5%) with asystole. No patients who required resuscitation for longer than 20 minutes in the ED survived to hospital discharge. CONCLUSION: The results of this study illustrate that patients with VT/VF have good potential for successful resuscitation. Prompt resuscitation and easy access for ACLS are the key factors for success. Survival rates are likely to improve if more lay people perform CPR and if emergency unit personnel are trained and allowed to perform ACLS.

Adult↗
PubMed1996

The effect of different levels of vitamin C and cholecalciferol with adequate or marginal levels of dietary calcium on performance and eggshell quality of laying hens.

Three experiments were conducted to determine whether shell quality, bone mineralization, and other production traits could be improved by adding vitamin C (ascorbic acid) to laying hen diets. The period of each experiment was 12 wk. Experiment 1 consisted of a 2 x 2 x 3 factorial design with two levels of Ca (2.8 and 3.8%), two levels of cholecalciferol (vitamin D3; 2,200 and 4,400 IU/kg diet), and three levels of vitamin C (0, 125, and 250 ppm). Experiment 2 consisted of a 2 x 3 x 2 factorial design with two levels of Ca (2.8 and 3.8%), three levels of vitamin D3 (250, 500, and 2,000 IU/kg diet), and two levels of vitamin C (0 and 250 ppm). Experiment 3 consisted of a 2 x 4 factorial design with two sources of vitamin D3 (12.5 micrograms vitamin D3/kg diet or 12.5 micrograms 25-OH-D3/kg diet) and four levels of vitamin C (0, 250, 500, and 1,000 ppm). Calcium level was kept constant at 3.5% for all the diets in Experiment 3. Production performance was not influenced by dietary treatments in Experiment 1. In Experiment 2, feed conversion was improved (P < 0.05) due to increasing the dietary Ca, and egg weight and egg size were increased (P < 0.05) due to adding 250 ppm vitamin C to the diet. In experiment 3, albumen quality was increased by the addition of 1,000 ppm vitamin C to the diet. Egg specific gravity was increased in Experiments 1 and 2 only, due to increasing the Ca level (P < 0.05). In Experiment 2, increasing the Ca level and increasing the vitamin D3 level from 250 to 2,000 ppm reduced (P < 0.05) the number of cracked eggs, but incidence of cracked eggs was increased with the addition of 250 ppm vitamin C to the diet. In Experiment 1, plasma level of 1,25(OH)2D3 was greater (P < 0.05) for hens fed 2.8 than 3.8% Ca, but blood acidbase balance was not influenced by dietary regimens. Bone ash was not influenced by dietary treatments in any of the experiments. The data indicated that a supplemental level of vitamin C had no beneficial effects on shell quality and bone mineralization under the conditions of the current experiments.

Aging↗
PubMed1983

The performance of four strains of laying hens subjected to various postrest combinations of calcium and phosphorus after forced rest in winter or summer.

Four strains of laying hens, including one brown egg strain, were force-rested in February at approximately 62 weeks of age. Hens from the same four strains, which were the same age, were also force-tested under similar conditions during August of the same year. In each of the two trials, a total of 2300 hens were housed at the rate of two per 25.4 x 45.7-cm cage. The resting procedure for both studies included feed withdrawal for 9 or 10 days followed by feeding a 8.6% protein diet for 25 days. Water was supplied at all times. After the 35-day resting period, the hens were assigned to four calcium and phosphorus combinations, which varied from the duplication of a first-year pullet phase feeding program to the feeding of a final phase type diet for the entire postrest production period. Nutrient level within each dietary system was adjusted periodically based on daily feed intake. Strain performance differences were observed in both seasons. Rate of return to production and postrest production rates were similar to the patterns observed within the respective strain's performance during the pullet year. This was noted in both studies. Relative strain production performance, however, when compared to the other strains, was not consistent between the two rest seasons. There was no difference in performance due to calcium and phosphorus treatment utilized in either postrest production season.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗
PubMed2002

Effects of dietary chromium and ascorbic acid supplementation on digestion of nutrients, serum antioxidant status, and mineral concentrations in laying hens reared at a low ambient temperature.

This experiment was conducted to evaluate the effects of chromium (chromium picolinate, CrPic) and vitamin C (L-ascorbic acid) supplementation on the digestion of nutrients and serum concentration of some antioxidant vitamins and minerals of laying hens (Hy-Line) reared at a low ambient temperature (6.8 degrees C). One hundred twenty laying hens (32 wk old) were divided into 4 groups, 30 hens per group. The laying hens were fed either a basal diet or the basal diet supplemented with either 400 microg of Cr/kg diet, 250 mg of L-ascorbic acid/kg diet, or 400 microg of Cr plus 250 mg L-ascorbic acid/kg diet. The digestibility of nutrients (DM, OM, CP, and EE) increased by the supplementation of chromium and vitamin C (p < 0.05). Supplemental chromium and vitamin C also increased serum vitamin C and E but decreased malondialdehyde concentrations (p < 0.05). Additionally, supplemental chromium and vitamin C caused an increase in the serum concentrations of Fe, Zn, Mn, and Cr (p < 0.05) but a decrease in Cu concentration. The results of the present study showed that each dietary supplement influenced most of the parameters measured in a similar way. Also, a combination of the two supplements resulted in an additive effect, and supplementing a combination of vitamin C (250 mg/kg of diet) and chromium (400 microg Cr/kg diet) may offer a potential protective management practice in preventing cold-stress-related depression in the performance of laying hens.

Animal Feed↗
PubMed2002

Effects of dietary chromium and zinc on egg production, egg quality, and some blood metabolites of laying hens reared under low ambient temperature.

This experiment was conducted to evaluate the effects of chromium (chromium picolinate, CrPic) and zinc (ZnSO4 x H2O) on egg production, egg quality, and serum insulin, corticosterone, glucose, cholesterol, and total protein concentrations of laying hens reared under a low ambient temperature (6.8 degrees C). One hundred twenty laying hens (Hy-Line; 32 wk old) were divided into 4 groups, 30 hens per group. The laying hens were fed the control diet (T1) or the control diet supplemented with either 400 microg of Cr/kg of diet (T2), 30 mg of Zn/kg of diet (T3), or 400 microg of Cr plus 30 mg of Zn/kg of diet (T4). Although the dry matter intake (DMI) was similar (p > 0.05) for all treatment groups, supplemental chromium and zinc either individually or together increased live-weight change, egg production, and improved feed efficiency (p < 0.05). However, no significant differences were observed between T4 and T2 or T3. Compared to T1, supplemental chromium and zinc increased egg weight, eggshell weight, eggshell thickness, egg specific gravity, and Haugh unit (p < 0.05) in T2, T3, and T4 groups, among which there was no significant difference. Serum insulin concentration increased (p < 0.05) and corticosterone concentration decreased (p < 0.05) with dietary chromium and zinc supplementation. Serum glucose and choles- terol concentrations decreased (p < 0.05) and protein concentrations increased (p < 0.001) with dietary chromium and zinc supplementation in all treatment groups. The results of this study indicated that either supplemental dietary chromium or zinc increased plasma insulin and decreased corticosterone concentrations and that had a positive effect on performance of laying hens under low ambient temperature.

Animals↗
PubMed2000

Effect of roxarsone inclusion in the diet on the performance and hepatic lipid metabolism of laying Tsaiya duck.

1. The aim of this study was to examine the effects of roxarsone (3-nitro-4-hydroxyphenylarsonic acid) inclusion in the diet on the performance, liver function and lipid metabolism in the liver of laying Brown Tsaiya ducks. 2. Sixty 36-week-old laying ducks were selected and allocated at random into 4 dietary treatments with 3 replications for each treatment. Feeding was for 7 weeks with 3 weeks of experimental diets followed by a 4 week withdrawal period. The experimental diets were supplemented with 0, 50, 100 and 300 mg/kg roxarsone, respectively 3. Dietary inclusion of 50 or 100 mg/kg roxarsone did not significantly promote performance. Inclusion of 300 mg/kg significantly depressed (P<0.05) performance, liver weight and content, serum triacylglycerol (TG), serum nonesterified fatty acid (NEFA) and increased (P<0.05) cholesterol, creatine kinase (CK) and aspartate aminotransferase (AST) in the serum at the end of 3 weeks on the experimental diet. 4. Laying characteristics returned to normal 4 weeks after withdrawal of roxarsone. The liver weight, fat and TG in the liver and serum concentrations of TG, NEFA, high density lipoprotein (HDL) and AST increased significantly (P<0.05), while the level of very low density lipoprotein (VLDL) decreased (P<0.05) at the end of the withdrawal period. More prominent vacuolised hepatic fatty cells were observed in laying ducks treated with 300 mg/kg of roxarsone.

Animals↗
PubMed1993

Ethics in cardiopulmonary resuscitation.

There is a minority of patients in whom resuscitation is inappropriate. It is important to identify such patients beforehand and communicate the decision not to attempt resuscitation to the would-be first responders. In the absence of the patient's expressed wishes, any decision not to attempt resuscitation must be made by the senior doctor in charge. This doctor will take into account a number of factors and, when appropriate, consult with medical and nursing colleagues relatives, etc. before making such a decision. There are many factors influencing the decision to terminate resuscitation once it has been started. These are listed and discussed. Legal aspects are addressed and indications are made of the expected performance of lay and professional rescuers working under a variety of circumstances. The various definitions of death are described in the light of modern medical practice and the possibility of organ transplantation. There is an increasing fear of infection hazards to the rescuer during mouth to mouth ventilation. The risks are discussed and the use of protective devices is encouraged if they are immediately available. Finally, guidelines for hospital ethical CPR policy are outlined in the hope that they will be considered for adoption on a national and international scale.

Brain Death↗
PubMed1986

Effect of serial blood sampling on interpretation of estradiol-17 beta involvement in laying hen calcium metabolism.

Effects of long-term, low levels of exogenous estradiol-17 beta and dietary calcium on calcium metabolism and laying hen performance, and effects of serial blood-sampling, were studied. Significant 3-way (P less than 0.01) and 2-way (P less than 0.05) interactions involving sampling obscured possible main effects (Exp. 1); no main effects were found in absence of blood sampling (Exp. 2). Estradiol-17 beta appears to increase calcium utilization with very low dietary calcium only. Relatively small brachial vein samples taken only every 3-4 weeks have substantial confounding effects on interpretation of data.

Animals↗
PubMed2000

Priapism after androstenedione intake for athletic performance enhancement.

Priapism is a relatively rare condition characterized by persistent painful erection of the corpora cavernosum that occurs unrelated to sexual stimulation or desire. It has been associated with cocaine exposure, sickle cell anemia, anticoagulant therapy, neoplastic syndromes, diabetes, and the use of psychotropic medications. Androstenedione is a testosterone precursor used by athletes to enhance performance; the lay press has recently touted this substance as an over-the-counter sexual stimulant. We describe an otherwise healthy man with 2 episodes of priapism after the use of androstenedione. The patient did not have any factors known to precipitate priapism.

Adrenergic alpha-Agonists↗