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At least 631 records · Page 35Linked to original sources
PubMed2003

Hypercapnia increases core temperature cooling rate during snow burial.

Previous retrospective studies report a core body temperature cooling rate of 3 degrees C/h during avalanche burial. Hypercapnia occurs during avalanche burial secondary to rebreathing expired air, and the effect of hypercapnia on hypothermia during avalanche burial is unknown. The objective of this study was to determine the core temperature cooling rate during snow burial under normocapnic and hypercapnic conditions. We measured rectal core body temperature (T(re)) in 12 subjects buried in compacted snow dressed in a lightweight clothing insulation system during two different study burials. In one burial, subjects breathed with a device (AvaLung 2, Black Diamond Equipment) that resulted in hypercapnia over 30-60 min. In a control burial, subjects were buried under identical conditions with a modified breathing device that maintained normocapnia. Mean snow temperature was -2.5 +/- 2.0 degrees C. Burial time was 49 +/- 14 min in the hypercapnic study and 60 min in the normocapnic study (P = 0.02). Rate of decrease in T(re) was greater with hypercapnia (1.2 degrees C/h by multiple regression analysis, 95% confidence limits of 1.1-1.3 degrees C/h) than with normocapnia (0.7 degrees C/h, 95% confidence limit of 0.6-0.8 degrees C/h). In the hypercapnic study, the fraction of inspired carbon dioxide increased from 1.4 +/- 1.0 to 7.0 +/- 1.4%, minute ventilation increased from 15 +/- 7 to 40 +/- 12 l/min, and oxygen saturation decreased from 97 +/- 1 to 90 +/- 6% (P < 0.01). During the normocapnic study, these parameters remained unchanged. In this study, T(re) cooling rate during snow burial was less than previously reported and was increased by hypercapnia. This may have important implications for prehospital treatment of avalanche burial victims.

Adult↗
PubMed1989

HLA and allopurinol drug eruption.

Strong HLA associations were found in Southern Chinese patients with skin eruptions due to allopurinol. The positive associations were with AW33 (Pc = 1.7 x 10(-5); relative risk [RR] = 15.0, 95% confidence limit 5.2-42.9) with B17/BW58 (Pc = 2.9 x 10(-9); RR = 46.3, 95% confidence limit 10.3-209.2). The negative association was with A2 (Pc = 8.3 x 10(-5), RR = 0). The findings suggested a genetic predisposition to cutaneous drug reactions.

Allopurinol↗
PubMed1991

Treatment of symptomatic metastatic prostatic cancer with cyproterone acetate versus orchiectomy: a prospective randomized trial.

During a 2-year period, 37 patients with symptomatic metastatic prostatic cancer were included in a prospective randomized phase-III trial. Nineteen patients were randomized to subcapsular orchiectomy, and 18 to cyproterone acetate (CPA) treatment with a dose of 50 mg b.i.d. The median age of the patients was 74 years (range 48-88 years), with no differences between the treatment groups. At 3, 6, and 12 months after initiation of the therapy and then every 6 months, patients were clinically and biochemically examined, and isotope scans and X-rays were performed. All patients were followed until death. Relief from symptoms was found following 3 months of treatment in 70.6% (95% confidence limits = 44.0-89.7%) of the patients treated with CPA, and in 83.3% (95% confidence limits = 58.6-96.4%) of the orchiectomized patients. The median time to relapse was 9 months in the CPA group, and 11 months in the orchiectomy group (p greater than 0.05). The median survival time was 13 months, with no differences between the groups. The treatment of advanced prostatic cancer with CPA is found to be a valuable alternative to orchiectomy.

Adenocarcinoma↗
PubMed1987

High-dose induction chemotherapy with cyclophosphamide, etoposide, and cisplatin for extensive-stage small-cell lung cancer.

To exploit possible dose-response and combination drug synergism, 20 previously untreated patients with extensive-stage small-cell lung cancer (SCLC) received one or two courses of high-dose induction chemotherapy consisting of cyclophosphamide (100 mg/kg), etoposide (1,200 mg/m2), and cisplatin (120 mg/m2) (HDCEP). HDCEP was followed by four cycles of standard-dose cyclophosphamide (1,000 mg/m2), doxorubicin (40 mg/m2), and vincristine (1.4 mg/m2) (CAV). Response was determined after HDCEP and following CAV. Reevaluation included repeat bronchoscopy and chest computerized tomography (CT), as well as repetition of all initially abnormal studies. All patients were evaluable for response and toxicity. Overall response to HDCEP was 90%, with a complete response (CR) rate of 65% (95% confidence limits, 44% to 86%) and a partial response (PR) rate of 25% (95% confidence limits, 6% to 44%). All patients either maintained or improved their initial response while receiving CAV. Median duration of response was 6 months (range, 2 to 12 months) and median survival was 9.5 + months (range, 2 to 21 + months). All 37 courses of HDCEP were associated with leukopenia (less than 1,000/microL), 92% with thrombocytopenia (less than 20,000/microL), and 84% with fever of greater than 38.5 degrees C. Additional toxicities included bacteremia (24%), nausea and emesis (59%), mucositis (57%), diarrhea (38%), and hemorrhagic cystitis (5%). There were two treatment-related deaths due to infection. A third patient died 4 months after completing HDCEP with pulmonary fibrosis. Although response duration and median survival were not improved, HDCEP produced a high CR rate in ambulatory patients with extensive-stage SCLC.

Aged↗
PubMed1990

Propranolol may prevent recurrence of oesophageal varices after obliteration by endoscopic sclerotherapy.

In 29 patients admitted with their first bleeding episode from oesophageal varices the varices were obliterated within 6 months by treatment with serial endoscopic sclerotherapy and propranolol or with sclerotherapy only. The patients were checked regularly during 18 months after the varices had been obliterated. Variceal recurrence was found in 11 patients (73%; 95% confidence limits, 45-92%) treated with sclerotherapy only and in 2 patients (15%; 95% confidence limits, 2-43%; p less than 0.01) treated with sclerotherapy and propranolol. In nine patients (69%) with recurrence significant variceal bleeding occurred. All recurrences were observed within 12 months after the initial obliteration. Variceal recurrence occurred in 3 Child A patients and in 10 Child B or C patients. All bleeding occurred in Child B or C patients. It is concluded that obliteration of oesophageal varices by endoscopic sclerotherapy and propranolol may be more effective in the long-term control of variceal recurrence than treatment with sclerotherapy only.

Adult↗
PubMed1991

Repeat coronary artery bypass grafting.

In 1981-1989 we performed repeat coronary artery bypass grafting on 42 men and 10 women (mean age 55 years) with angina pectoris recurring on average 27 months after the primary operation. The cause was occlusion or stenosis of vein grafts alone (59%) or in combination with progression of native coronary atherosclerosis (31%) or progression in the native circulation without graft failure (10%). Complications at the repeat operation included five lesions of the right ventricle and five lesions of patient grafts. The 30-day mortality was 3.8% (95% confidence limits 0.5-13.2%). Survival after observation averaging 2 1/2 years was 92.3% (95% confidence limits 81.5-97.9%). Angina pectoris was completely relieved after the operation in 48% of the patients, lessened in 35% and unchanged in 17%. Although repeat coronary artery bypass grafting carries heightened mortality and morbidity, and the results are less satisfactory than after first-time bypass, the operation can be worthwhile.

Angina Pectoris↗
PubMed1997

Inhibitory effects of copper-aspirin complex on platelet aggregation.

AIM: To study the inhibitory effects of copper-aspirin complex (CuAsp) on platelet aggregation. METHODS: With adenosine diphosphate the effects of CuAsp on platelet aggregation in vitro or in vivo were investigated. Radioimmunoassay and fluorophotometry were used to measure thromboxane B2 (TXB2) generation from platelets, the levels of TXB2 and of 6-keto-PGF1 alpha in plasma and the platelet serotonin release reaction. RESULTS: In vitro, CuAsp inhibited arachidonic acid (AA)-induced aggregation (IC50 = 17 mumol.L-1, 95% confidence limits: 9-33 mumol.L-1), the release of 5-HT (IC50 = 19 mumol.L-1, 95% confidence limits: 10-30 mumol.L-1), and TXB2 generation from platelets (P < 0.05). CuAsp 10 mg.kg-1 i.g. selectively inhibited AA-induced aggregation, and increased the 6-keto-PGF1 alpha concentration in plasma while decreased that of TXB2. CONCLUSION: CuAsp, in vitro or in vivo, shows more potent inhibitory effects on AA-induced aggregation than aspirin (Asp), related to the inhibition of platelet cyclooxygenase and the release of active substances from platelets.

6-Ketoprostaglandin F1 alpha↗
PubMed1999

Thyroid function in thalassaemia major.

INTRODUCTION: Short stature is common in thalassaemia major. Hypothyroidism resulting from haemosiderosis has been implicated, but this complication has not been investigated in Sri Lanka. OBJECTIVES: To estimate the thyroid hormone level of patients with thalassaemia major and correlate height with age, iron status and thyroid hormone level. SETTING: University Unit, Lady Ridgeway Hospital, Colombo. DESIGN: A cross-sectional comparative study. METHODS: 33 patients with thalassemia major (19 males) aged 2 years 6 months to 23 years were studied. 21 healthy age and sex matched subjects from the same neighbourhood as the patients served as controls. Anthropometric measurements, skeletal maturity, serum ferritin and thyroid hormone levels were estimated. RESULTS: The height centiles and height standard deviation scores (SDS) were significantly lower in the patient group. Skeletal maturation was delayed by more than 1 year in 69% of patients. Undernutrition was not seen. The height SDS showed significant reduction with age (r = -0.5, 95% confidence limit -0.72 to -0.18) and with elevated serum ferritin levels (r = -0.8, 95% confidence limit = -0.9 to 0.62). Serum ferritin levels were elevated in the entire patient group with 70% being heavily iron overloaded (serum ferritin > 7000 ng/ml). The thyroxine (T4) levels were within the normal range in all 33 patients. The TSH levels were normal in 32 patients. The patient too had a normal T4 level. The control group had TSH levels comparable with the patients. CONCLUSION: Hypothyroidism was not present in our iron overloaded thalassaemic patients. The thyroid hormone levels were similar in patients with mild and heavy iron overload. We conclude that routine surveillance for hypothyroidism is unnecessary in thalassaemia major. Other causes for delayed skeletal maturation and short stature need investigation.

Adolescent↗
PubMed2002

Inhibitory effects of DDPH on two components of delayed rectifier potassium current in guinea pig ventricular cells.

AIM: To study the effects of 1-(2,6-dimethylphenoxy)-2-(3,4-dimethoxy-phenyl-ethylamino) propane hydro-chloride (DDPH) on the rapidly activating component (I(Kr)), and the slowly activating component (I(Ks)) of the delayed rectifier potassium current (I(K)) in guinea pig ventricular myocytes. METHODS: Whole-cell patch clamp recording techniques. RESULTS: DDPH (0.1-100 micromol/L) blocked the I(Kr) in a concentration-dependent manner. The IC50 (micromol/L) was 6.1 (95 % confidence limits: 2.8-13.5). IC50 (micromol/L) of DDPH blocking I(Ks) was 12.5 (95 % confidence limits: 4.8-32.2). DDPH (10 micromol/L) did not affect activation time constants and the voltage-dependent activation of both I(Kr) and I(Ks), the half-activation voltage (V1/2, mV) and slope factor (k, mV) were I(Kr): -23.5+/-2.4 and 8.1+/-2.2 [in presence of DDPH, P >0.05, compared with control, V1/2 (-21.7+/-0.8) and k (5.9+/-0.8)]; I(Ks): 27.1+/-0.7 and 16.6+/-0.8 [in presence of DDPH, P >0.05, compared with control, V1/2 (27.0+/-0.8) and k (14.9+/-0.9)]. DDPH slightly increased the deactivation time-constant of I(Kr) ( r) and I(Ks) ( s) at low concentration (<10 micromol/L). The inactivation of I(Kr) was significantly accelerated by DDPH. CONCLUSIONS: DDPH inhibited both I(Kr) and I(Ks). The blockade was not due to its influence on activation, but the process of deactivation. The blocking of I(Kr) by DDPH was further associated with its acceleration the channel inactivation.

Animals↗
PubMed1992

Quantitative analysis of ventricular late potentials (LP) in healthy subjects. Comparative study with Holter monitoring.

Signal averaging is a technique that improves the signal-to-noise ratio. It allows the detection of low-amplitude wave formes in the terminal portion of the QRS complex, also known as ventricular late potentials. A high incidence of arrhythmic events is found in patients with abnormal ventricular late potentials after an acute myocardial infarction. Few wide studies have been conducted in healthy subjects to assess normal values. One hundred sixty-five healthy subjects are enrolled in our study (59 men and 106 women). The results (mean +/- standard deviation) are as follows: duration of filtered QRS: 89.5 +/- 9.1 ms; duration of the low-amplitude signals in the terminal portion of QRS < 40 microV: 27.1 +/- 7.8 ms; root-mean-square voltage in the last 40 ms: 47.2 +/- 29.5 microV. A signal difference is noted between men and women for the QRS duration. No difference is found in HFD40 and RMS40. QRS duration confidence limits of 95% are < 108 ms for the total group. HFD40 and RMS40 confidence limits of 95% are respectively of 43 ms and 13 microV. There is no significant difference of the values for age. There is no relation between the severity of a ventricular arrhythmia and the values of the three parameters of the late potentials in a healthy subjects population.

Adult↗
PubMed1990

Randomised, double-blind, placebo-controlled trial of nimodipine in acute stroke. Trust Study Group.

The value of oral nimodipine 120 mg per day for acute stroke was assessed in a randomised, double-blind, placebo-controlled multicentre study of 1215 patients. The primary end-point was independence after 6 months, defined as a score of 60 or more on an activities of daily living (ADL) scale, the Barthel index. Patients were entered into the trial if they were aged over 40, became hemiparetic in the previous 48 h, were conscious, were able to swallow, and had been living independently before the stroke. At 6 months, 55% of the nimodipine group and 58% of the placebo group were independent, the odds ratio for independence on nimodipine being 0.88 (95% confidence limits 0.70-1.10). For mortality the odds ratio with nimodipine was 1.22 (95% confidence limits 0.95-1.57). ADL and neurological scores also suggested delayed recovery in the nimodipine group at 3 weeks. The results do not support the case for oral nimodipine therapy 120 mg per day starting within 48 h of the stroke, for patients with acute stroke.

Activities of Daily Living↗
PubMed1984

Elevated 24-hour mean plasma concentration of FSH in men with cirrhosis of the liver.

Twenty-four-hour mean plasma concentrations of estradiol, estrone, testosterone, LH and FSH were measured in 6 men with typical alcoholic liver cirrhosis and in 17 age-matched controls. Plasma estradiol levels were markedly elevated in the cirrhotic patients, as has been reported before. Plasma levels of estrone, testosterone and LH did not differ significantly from normal. The most striking finding was marked elevation of the plasma FSH level: the mean value in the cirrhotic group was 19.5 mIU/ml (95% confidence limits, 13-29), more than twice the mean control value, 9.7 mIU/ml (95% confidence limits, 7.0-13) (p less than 0.0005). This consistent elevation of FSH in cirrhotic men may be due to a deficient testicular secretion of inhibin as a result of alcohol toxicity to the testes.

Adult↗
PubMed1976

Anti-colon antibodies in ulcerative colitis. A clinical study.

145 consecutively admitted patients with ulcerative colitis were clinically classified. A female:male ratio of 1.46:1 was found. Clinical symptoms and signs presumed to indicate hypersensitivity were present in 30% (95% confidence limits 23-39%). Circulating anti-colon antibodies were found in 20% (95% confidence limits 14-28%) with a female preponderance of 2.63:1. None of the following factors were significantly correlated to the presence of anti-colon antibodies: the age or sex of the patients, the degree of colonic involvement, duration of disease, age of onset, family history of disease, or manifestations of hypersensitivity associated with ulcerative colitis.20

Acute Disease↗
PubMed1994

Evaluation of unstented aortic homografts for the treatment of prosthetic aortic valve endocarditis.

BACKGROUND: Prosthetic aortic valve endocarditis is a serious complication that carries a high morbidity and mortality. Aortic homografts have been used in this setting, but long-term results are not available. METHODS AND RESULTS: Over a 23-year period, 48 patients presented with infected aortic valve substitutes: 28 homografts, 15 mechanical, and 5 xenografts. Nineteen patients had emergency surgery, and the mean interval between the first and second operation was 5.9 years (range, 1 month to 22 years). In 28 patients, the preoperative New York Heart Association (NYHA) class was III or IV. Active endocarditis was present in 39 patients, and the microorganisms grown were Staphylococcus epidermidis (n = 13), Staphylococcus aureus (n = 6), Streptococcus viridans (n = 6), Streptococcus faecalis (n = 4), Candida albicans (n = 5), and Gram-negative spp (n = 2). Aortic root abscesses were found in 28 (58%) patients, and transesophageal echocardiography was 95% accurate in their localization. All patients received homograft aortic valves, 19 as root replacement and 29 using the freehand technique. There were four (8.3%) early deaths; poor left ventricular function and concomitant procedure were identified as risk factors. At a mean follow-up of 4 years (range, 2 months to 19 years) 95% of the patients were in NYHA class I or II without significant aortic regurgitation. The actuarial survival at 5 years was 97% (confidence limit, 84% to 100%), and freedom from endocarditis at 10 years was 97% (confidence limit, 84% to 100%). Multivariate analysis did not identify risk factors for these late events. CONCLUSIONS: Homograft aortic valves offer good early and long-term results in patients with infected aortic valve substitutes.

Actuarial Analysis↗
PubMed1995

Software for illustrative presentation of basic clinical characteristics of laboratory tests--GraphROC for Windows.

GraphROC for Windows is a program for clinical test evaluation. It was designed for the handling of large datasets obtained from clinical laboratory databases. In the user interface, graphical and numerical presentations are combined. For simplicity, numerical data is not shown unless requested. Relevant numbers can be "picked up" from the graph by simple mouse operations. Reference distributions can be displayed by using automatically optimized bin widths. Any percentile of the distribution with corresponding confidence limits can be chosen for display. In sensitivity-specificity analysis, both illness- and health-related distributions are shown in the same graph. The following data for any cutoff limit can be shown in a separate click window: clinical sensitivity and specificity with corresponding confidence limits, positive and negative likelihood ratios, positive and negative predictive values and efficiency. Predictive values and clinical efficiency of the cutoff limit can be updated for any prior probability of disease. Receiver Operating Characteristics (ROC) curves can be generated and combined into the same graph for comparison of several different tests. The area under the curve with corresponding confidence interval is calculated for each ROC curve. Numerical results of analyses and graphs can be printed or exported to other Microsoft Windows programs. GraphROC for Windows also employs a new method, developed by us, for the indirect estimation of health-related limits and change limits from mixed distributions of clinical laboratory data.

Clinical Laboratory Techniques↗
PubMed1994

The use of confidence intervals to describe the precision of trough/peak ratios for diltiazem CD in the treatment of hypertension.

Once-daily diltiazem hydrochloride, CARDIZEM CD (diltiazem CD) 300 mg, was evaluated for safety, efficacy, and the relationship between peak and trough antihypertensive effects in a multicenter, placebo-controlled, parallel design trial. After a 4- to 6-week placebo baseline period, 111 patients with essential hypertension were randomized to receive placebo or diltiazem CD for a 4-week treatment period. Diltiazem CD 300 mg lowered supine diastolic and systolic blood pressure at trough significantly more than placebo (-7.5 mm Hg vs. -1.3 mm Hg, P = 0.0001 and -6.4 mm Hg vs. 0.5 mm Hg, P = 0.0051, respectively). Supine blood pressure was also measured hourly from 6 to 10 hours after the dose to assess peak effect and trough/peak ratios. Using the largest residual drug effect of -8.3 mm Hg at 6 hours as peak and the 24-hour residual drug effect of -5.9 mm Hg as trough, the trough/peak ratio was estimated to be 71%, with a lower one-sided 95% confidence limit of 50%. The precision of the trough/peak ratio is estimated by the lower confidence limit of 50%, which establishes the trough/peak ratio as statistically > or = 50%. No statistically significant differences in supine DBP were noted between the peak effect hours, indicating a plateau of the peak antihypertensive effect from 6 to 10 hours postdose. Diltiazem CD therapy was well tolerated, with no serious treatment-related adverse events reported during the trial and no patients discontinuing the trial due to a treatment-related adverse event.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1985

On the role of aging in cancer incidence: an interpretation of the prostate cancer anomaly with implications for routine screening.

Cross-sectional age-incidence patterns for the common male and female cancers in Connecticut were normalized to describe the percentage of total incidence that occurred at each age. The pattern for prostate cancer was atypical--less than the 99% confidence limit from the mean at ages less than 60 and greater than the 99% confidence limit from the mean at ages greater than 75. The available international data on latent carcinoma of the prostate, when normalized as above, resembled the mean male and female cancer patterns in Connecticut and suggested that the atypical behavior of clinical prostate cancer was the result of a lag between the incidence of latent carcinoma and promotion to clinical disease. Confirmation of this suggestion, with the potential to distinguish epidemiologically those latent carcinomas that remain asymptomatic from those that progress to malignancy, awaits routine screening for the latent carcinoma.

Aged↗
PubMed1993

The gene for spondyloepiphyseal dysplasia (SEDL) maps to Xp22 between DXS16 and DXS92.

Previous linkage studies in X-linked spondyloepiphyseal dysplasia (SEDL) placed the gene in the region Xp22.2-p22.1 by linkage to DXS41. Here we have extended our earlier studies by analyzing 15 families with 13 markers from the Xp22 region. Pairwise linkage analysis revealed significant linkage of the SEDL to 8 markers from the Xp22.2-Xp22.1 region. Maximum lod scores were obtained with DXS207, tau max = 9.16 at theta max = 0.021 with confidence limits of 0.00-0.09, and DXS197, tau max = 7.98 at theta max = 0.00 with confidence limits of 0.00-0.06. The study of one recombinant in family 4 indicated that DXS 41 is more likely proximal to DXS92 than distal. Multipoint linkage results and analysis of recombination events indicated that the mutation responsible for SEDL is located in Xp22 between DXS 16 and DXS 92.

Chromosome Mapping↗