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At least 307 records · Page 17Linked to original sources
PubMed1976

Computer interpreted fetal electroencephalogram. I. Relative frequency of patterns.

Fetal electroencephalography (FEEG) is a clinical research technique for monitoring the electrical activity of the fetal brain during labor. Because of the massive volume of data, it has not previously been practicable to quantify the frequency of occurrence of the various patterns by visual analysis. With the use of a computer program, which has been shown to be consistent with visual interpretations, records for 11 fetuses, known to be neurologically normal at 1 year of age, were analyzed. Adequate FEEG had been recorded 73.6 per cent of the time during which the fetuses were monitored. In 10,511 10 second epochs of adequate FEEG, the Mixed pattern was found to be dominant, with a relative frequency of 41.2 per cent. The relative frequencies of Trace Alternant and High Voltage Slow activity were 32.3 per cent and 21.5 per cent, respectively. Low Voltage Irregular, Voltage Depression, and Isoelectricity occurred infrequently, accounting for approximately 4.6 per cent of the epochs. The relative frequencies of the various patterns were stable from the onset of monitoring of FEEG through neonatal EEG obtained in the delivery room. These data will form the basis for subsequent studies of FEEG changes associated with various endogenous and exogenous factors.

Computers↗
PubMed1979

Use of contraceptives prior to and after conception and exposure to other fetal hazards.

In a large prospective study, set up to determine whether reproductive outcomes are affected by prior contraceptive use, 34,344 women were recruited at their first antenatal visit and followed until pregnancy termination. This paper summarizes the study methods and describes the demographic differences between subjects who used various contraceptives shortly before conception, and those who experienced contraceptive failures. Thirty percent of the women had used oral contraceptives (OCs) during the 5 months prior to conception and 2.4% had continued using them after their LMP. IUDs had been used by 5.8% of women before conception and 1.1% after. If these rates are also true for the whole population of the U.S., they indicate that approximately 70,000 babies are born each year following pill-failures and 30,000 following failures of IUD's. Exposure to other fetal hazards was common, with 48% of pregnant women drinking alcohol, 28% smoking, and 15% receiving diagnostic X-rays. OC use was more common among smokers and drinkers, and OC failures were significantly associated with the use of anti-epileptics, aspirin, and with exposure to radiation.

Adult↗
PubMed1980

A clinical trial of Neo Sampoon vaginal contraceptive tablets.

Results are reported of a clinical trial of Neo Sampoon vaginal contraceptive tablets, conducted by the International Fertility Research Program (IFRP) in collaboration with the Dacca Medical College Hospital, Bangladesh. Of the 150 women enrolled, 115 remained in the study at the end of 12 months. The 12-month cumulative gross life-table rates per 100 women were 6.5 for pregnancy and 24.8 for discontinuation due to other reasons. Discomfort associated with the heart generated by the tablets' effervescence was the primary side effect of Neo Sampoon use, and was one of the major causes of discontinuation. Regularity of use and acceptability of this foaming tablet appeared to be high compared to other barrier methods. Further research is needed on Neo Sampoon and other vaginal contraceptives to develop and promote methods that can help meet the worldwide demand for fertility control.

Actuarial Analysis↗
PubMed1984

Laparoscopic sterilization in a free-standing clinic: a report of 1,092 cases.

The five-year experience of 1,092 laparoscopic tubal sterilizations performed in a free-standing clinic in the U.S. with no anesthesiologist under local anesthesia is reviewed. The current technique of the Hasson "open" method and bipolar cauterization is felt to minimize major mishaps and is acceptably comfortable to the patient.

Adolescent↗
PubMed1985

Gossypol and hypokalaemia.

One major side effect of administration of gossypol as a male fertility regulating agent is the occurrence of hypokalaemic paralysis. We have reviewed the common causes of hypokalaemia in clinical practice and previous studies of gossypol-induced hypokalaemia in animals and man. The available evidences suggest that gossypol induced renal leakage of potassium. The most likely mechanism is a direct toxic effect of gossypol on the renal tubules.

Animals↗
PubMed1991

Anti-idiotypic and anti-anti-idiotypic antibodies as highly specific tools in epitope and active site studies on human interferon-gamma.

Immunization of rabbits with F(ab')2 fragments of different monoclonal antibodies directed against human interferon-gamma yielded antisera with anti-idiotypic characteristics. Isolation of the anti-idiotypic fraction, resulting in a highly specific antiserum, allowed us to prove that out of six competing monoclonal antibodies directed against human interferon-gamma, only two really recognize the same epitope. The other monoclonal antibodies compete on the basis of steric hindrance, which is not surprising, because of the large difference in Mr between interferon-gamma and an immunoglobulin. The anti-idiotypes provided us also with a tool to study isolated epitopes on the human interferon-gamma molecule, a task which was previously not practicable. Exploration of the biological properties of these anti-idiotypes allows us to determine whether the investigated epitopes are involved in receptor binding. The production of an anti-anti-idiotypic antiserum not only proved that we generated real internal images, but also that these images conserved all of their properties, although with a decreased affinity in comparison with the original monoclonal antibody. As the former is a polyclonal antiserum, directed against a single epitope of the human interferon-gamma molecule, competition experiments yielded additional information on the relative position of three epitopes recognized by inhibiting monoclonal antibodies. These antisera will possibly open new ways for the affinity purification of interferon-gamma and perhaps for the treatment of autoimmune diseases.

Animals↗
PubMed1995

High-performance liquid chromatographic determination of urinary 4'-hydroxymephenytoin, a metabolic marker for the hepatic enzyme CYP2C19, in humans.

The preferential hydroxylation of (S)-mephenytoin to 4'-hydroxymephenytoin (4'-OH-M) displays a genetic polymorphism of drug metabolism in humans. Thus the excreted 4'-OH-M is considered to be an important marker for the hepatic (S)-mephenytoin 4'-hydroxylase. Accordingly, a mixture of urine containing total 4'-OH-M after enzymatic deconjugation and phenobarbital as internal standard (I.S.) was extracted with absolute diethyl ether. The residue remaining after evaporation was dissolved in 50 microliters of eluate and 20 microliters were injected into the chromatographic system. All components were separated isocratically on a reversed-phase column using acetonitrile-water (24:76, v/v) as the mobile phase at a flow-rate of 1.2 ml/min. The effluent was monitored at 204 nm. The retention times for 4'-OH-M and the I.S. were within 6 min. The absolute recovery was in the range 84-89% for 4'-OH-M and that of the I.S. was 75.9 +/- 4.2%. Quantification was performed by measuring the peak-height ratio compared with the ratio of the amount of 4'-OH-M divided by that of the I.S. The intra- and inter-day variations were less than 8% and 10%, respectively. The proposed method is simpler and more convenient than those reported previously. Its practical applicability was assessed by phenotyping the efficient and deficient hydroxylators among the Chinese minorities and Han Chinese populations.

Aryl Hydrocarbon Hydroxylases↗
PubMed1994

Vitreous alcohol is of limited value in predicting blood alcohol.

Vitreous humour alcohol concentration (VHAC) and blood alcohol concentration (BAC) measured by gas chromatography were available from 345 medico-legal autopsies. Simple linear regression with BAC as outcome variable and VHAC as predictor variable (range 1-705 mg%) gave the regression equation BAC = 3.03 + 0.852 VHAC with 95% prediction interval +/- 0.019 square root of [7157272 + (VHAC - 189.7)2] and 99% prediction interval +/- 0.025 square root of [7157272 + (VHAC - 189.7)2]. The residual standard deviation of VHAC was 26 mg%, the standard error of the slope 0.0098 and the 95% confidence interval for the slope 0.833-0.871. In practice a BAC of 80 mg% is predicted with 95% certainty by a VHAC of 150 mg% and similarly a BAC of 150 mg% by a VHAC of 232 mg%. The prediction interval is too wide to be of real practical use. Previous authors have provided various formulae, including a simple conversion factor, to predict BAC from VHAC without taking into account the uncertainty of the prediction for an individual subject. A re-analysis of the raw data from previous publications gave in most instances regression equations significantly different from the authors' own.

Alcoholic Intoxication↗
PubMed1989

Carcinoma of the cervix and oral contraceptives: epidemiological studies.

The relationship between squamous carcinoma of the cervix and oral contraceptive use has been examined in a substantial number of epidemiological studies. On balance there is reasonably convincing evidence that prolonged oral contraceptive use slightly increases the risk of the disease, but some doubt remains as to whether or not confounding factors have been controlled adequately in the studies reporting positive findings. The data are too few at present for any reasoned comment to be made about the possible relationship between oral contraceptives and adenocarcinoma of the cervix.

Adenocarcinoma↗
PubMed2006

[Retraining between months 4 and 6 after anterior cruciate ligament reconstruction with hamstring graft: comparison between cycling and running with an untrained operated subject group].

OBJECTIVE: To study the effect of cycling or running retraining between 4 and 6 months after patients underwent anterior cruciate ligament reconstruction with hamstring grafting (Semitendinosus-Gracilis) compared with that in patients who had the same surgery but were untrained. METHOD: Patients who had undergone surgery for an anterior cruciate ligament reconstruction by the same surgeon who used hamstring grafting were included if they were free of knee pain 4 months after the surgery. After giving consent, patients were randomized to receive controlled retraining (cycling or running 3 times a week) or not. The effect of retraining was measured by the evolution of the knee isokinetic peak torque at 60 degrees/s and 180 degrees/s 6 months after surgery. RESULTS: Fifteen patients were retrained with cycling (GI), 17 with running (GII) and 15 patients did not retrain (GIII). Before retraining, the 3 groups had the same peak torque deficit, measured at an angular speed of 60 degrees/s and 180 degrees/s, for knee extensors (GI: 33+/-11% and 27+/-8%; GII: 30+/-13% and 24+/-10%; GIII: 31+/-15% and 24+/-13%, respectively) and knee flexors (GI: 26+/-11% and 20+/-13%; GII: 20+/-14% and 17+/-13%; GIII: 19+/-15% and 14+/-15%, respectively). After retraining, progress measured at 60 degrees /s of knee extensors and flexors on the operated knees was 18+/-9% and 16+/-10% for GI, 16+/-9% and 11+/-11% for GII and 12+/-15% and 8+/-12 for GIII, respectively. Progress measured at 180 degrees /s followed the same evolution. After comparison of the 3 groups, any significant difference was put in relief according to the type of retraining. CONCLUSION: Retraining after anterior cruciate ligament reconstruction is necessary for patients to practice their previous sport. In our study, aerobic cycling or running between 4 and 6 months after surgery did not improve peak torque in the operated knee extensors and flexors. However, these 2 types of retraining are well-tolerated.

Adult↗
PubMedDate not supplied

Sentinel lymph node biopsy.

The introduction of sentinel lymph node biopsy (SLNB) has been an important development in the management of malignant melanoma. Lymph nodes have long been known to play a key role in melanoma metastasis. The importance of nodal staging accounted for the previous surgical practice of elective lymph node dissection (ELND) even with its controversial impact on final outcomes and associated morbidity. Although this morbidity has been reduced with the ability to identify the SLN, numerous questions have subsequently surfaced with respect to this procedure's utility and therapeutic efficacy. This chapter will focus on the indications for SLNB, as well as the current controversies surrounding this procedure.

Humans↗
PubMed2003

Full-length telomerase reverse transcriptase messenger RNA is an independent prognostic factor in neuroblastoma.

Telomerase activity (TA) is the most recently recognized prognostic factor in neuroblastoma, and its outstanding predictive power was documented by several studies. However, TA measurements require fresh tumor tissue that is not always available in daily clinical practice. We previously described a reverse transcriptase-polymerase chain reaction assay that we used to investigate the possible prognostic relevance of the telomerase catalytic subunit, hTERT, at the mRNA level. Because hTERT mRNA undergoes alternative splicing as a regulatory mechanism of TA, we discriminated between truncated and full-length hTERT transcripts. In a retrospective study on 124 neuroblastomas, 56 (45.2%) tumors showed spliced hTERT transcripts, whereas 30 (24.2%) contained full-length hTERT transcripts. The presence of both spliced and full-length hTERT transcripts was significantly associated with MYCN amplification. hTERT in general showed no correlation to other prognostic factors, ie, International Neuroblastoma Staging System stage, International Neuroblastoma Pathology classification grade, or age at diagnosis, whereas the presence of full-length transcripts was significantly associated with higher stages. The presence of any hTERT transcripts carried no significant prognostic information, yet full-length hTERT transcripts were highly predictive of poor outcome (P < 0.0001). In a multivariate analysis, full-length hTERT transcripts and International Neuroblastoma Pathology classification grade emerged as the sole independent predictors of event-free survival, with relative risks of 10.0 and 3.9, respectively. The strong statistical correlation of full-length hTERT transcripts with clinical outcome in neuroblastoma suggests that the reverse transcriptase-polymerase chain reaction analysis of hTERT transcripts may be equatable to TA measurements. Because this assay is well suited for archival material, it could become a useful adjunct in evaluating the prognosis of individual neuroblastoma cases.

Brain Neoplasms↗
PubMed2000

On the use of computational fluid dynamics in the prediction and control of exposure to airborne contaminants-an illustration using spray painting.

Computational fluid dynamics (CFD) is employed to simulate breathing-zone concentration for a simple representation of spray painting a flat plate in a cross-flow ventilated booth. The results demonstrate the capability of CFD to track correctly changes in breathing-zone concentration associated with work practices shown previously to be significant in determining exposure. Empirical data, and models verified through field studies, are used to examine the predictive capability of these simulations and to identify important issues in the conduct of such comparisons. A commercially available CFD package is used to solve a three-dimensional turbulent flow problem for the velocity field, and to subsequently generate particle trajectories for polydisperse aerosols. An in-house algorithm is developed to convert the trajectory data to breathing-zone concentrations, transfer efficiencies and aerosol size distributions. The mesh size, time step, duration of the simulation, and number of particles per size interval are all important variables in achieving convergent results.

Humans↗
PubMed2000

Measurement of soluble transferrin receptor by immunoturbidimetry and immunonephelometry.

OBJECTIVE: To evaluate and compare two new commercially available immunoturbidimetric and immunonephelometric assays for measuring soluble transferrin receptor (sTfR) in serum. To adapt the immunonephelometric assay to an automated chemistry analyzer. DESIGN AND METHODS: Total imprecisions and detection limits were calculated and compared. Fifty-six samples were used for methods comparison. The nephelometric assay was adapted to the Hitachi 911 analyzer. RESULTS: Both methods displayed acceptable imprecisions and detection limits. Their correlation was good but a proportional bias was observed. The adaptation of the nephelometric assay to the Hitachi 911 was successful. CONCLUSIONS: These two new immunoassays are analytically acceptable and more practicable than previously developed methods. The differences observed between both methods underscores the need for standardization. The nephelometric assay was easily adaptable to an automated chemistry analyzer.

Biomarkers↗
PubMed1990

Fertility after contraception or abortion.

There is a very small correlation, if any, between the prior use of OCs and congenital malformations, including Down's syndrome. There are few, if any, recent reports on masculinization of a female fetus born to a mother who took an OC containing 1 mg of a progestogen during early pregnancy. However, patients suspected of being pregnant and who are desirous of continuing that pregnancy should not continue to take OCs, nor should progestogen withdrawal pregnancy tests be used. Concern still exists regarding the occurrence of congenital abnormalities in babies born to such women. The incidence of postoperative infection after first trimester therapeutic abortion in this country is low. However, increasing numbers of women are undergoing repeated pregnancy terminations, and their risk for subsequent pelvic infections may be multiplied with each succeeding abortion. The incidence of prematurity due to cervical incompetence or surgical infertility after first trimester pregnancy terminations is not increased significantly. Asherman's syndrome may occur after septic therapeutic abortion. The pregnancy rate after treatment of this syndrome is low. The return of menses and the achievement of a pregnancy may be slightly delayed after OCs are discontinued, but the fertility rate is within the normal range by 1 year. The incidence of postpill amenorrhea of greater than 6 months' duration is probably less than 1%. The occurrence of the syndrome does not seem to be related to length of use or type of pill. Patients with prior normal menses as well as those with menstrual abnormalities before use of OCs may develop this syndrome. Patients with normal estrogen and gonadotropin levels usually respond with return of menses and ovulation when treated with clomiphene. The rate for achievement of pregnancy is much lower than that for patients with spontaneous return of menses. The criteria for defining PID or for categorizing its severity are diverse. The incidence of PID is higher among IUD users than among patients taking OCs or using a barrier method. The excess risk of PID among IUD users, with the exception of the first few months after insertion, is related to sexually transmitted diseases and not the IUD. Women with no risk factors for sexually transmitted diseases have little increased risk of PID or infertility associated with IUD use. There appears to be no increased risk of congenital anomalies, altered sex ratio, or early pregnancy loss among spermicide users. All present methods of contraception entail some risk to the patient. The risk of imparied future fertility with the use of any method appears to be low.(ABSTRACT TRUNCATED AT 400 WORDS)

Abortion, Induced↗
PubMed1991

Oral contraceptives and breast disease.

Epidemiologic data support the hypothesis that the types of OCs used before the mid-1970s protected against most forms of benign breast disease. It is unclear whether current low-dose progestogen OCs will confer the same protection. Further studies are necessary to clarify this. For breast cancer, the relationship is more complex. It is possible that prolonged use of high-dose OCs exert a small increased risk for breast cancer development in women before age 45. Furthermore, prolonged use before a first term pregnancy may result in a small increase in risk for breast cancer before age 45. Studies evaluating the effect of current low-dose OCs are necessary to elucidate what, if any, effect they may have on breast cancer development. Furthermore, as our population ages, studies will be able to determine what effect, if any, may be present in women over age 60, those women with the highest underlying risk of breast cancer. And finally, more research of basic breast tissue physiology and the effect of endogenous and exogenous hormones on this complex organ is needed.

Breast↗
PubMed1987

Effects of hypoxia and glycolytic inhibition on electrical properties of sheep cardiac Purkinje fibres.

Active and passive electrical properties of sheep cardiac Purkinje fibres were determined using conventional microelectrode techniques. In addition, oxygen tension was monitored immediately adjacent to the fibres with oxygen sensing microelectrodes. Oxygen was withdrawn for 130 min in a glucose-free solution (PO2 less than 15 mmHg), glycogen breakdown inhibited by 2-4-deoxyglucose and the following effects observed: (i) a decrease in action potential duration by as much as 80%; (ii) a decrease in maximal rate of rise of the action potential (Vmax) by 52%; (iii) an increase in internal longitudinal resistance (ri) by 176%; and (iv) a decrease in conduction velocity (theta) by 47%. The magnitude of the effects depended on PO2 (range: 4 to 46 mmHg). In particular, ri was steeply dependent upon the PO2 of the medium (glycogenolysis also inhibited by 2-4-deoxyglucose): ri increased to 470% above control when PO2 was reduced to 4 mmHg versus only a 47% increase in ri at PO2 = 11 mmHg. These effects were largely reversible after re-oxygenation and washout of 2-4-deoxyglucose although the time course of recovery of ri lagged behind that of action potential duration. Similar to previous studies, practically no effect of hypoxia was observed on the electrical properties of Purkinje fibres when glycogenolysis was not inhibited. The measured decrease of theta correlated relatively well with that predicted from linear cable theory using the changes of (i) Vmax and (ii) ri. No significant changes in membrane capacitance and only minor changes in action potential amplitude developed during combined hypoxia and inhibition of glycolysis.

Action Potentials↗