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991.
BACKGROUND: The present study assessed the screening tests for Down syndrome available to women within Australian hospitals. METHODS: Postal questionnaires. RESULTS: A total of 282 (57%) hospitals responded with over two-thirds offering some form of screening test which varied by geographical region and level of institution. First trimester maternal serum screening was offered by 11% of hospitals. Nuchal translucency screening was offered by 52% of hospitals with higher use in Australian Capital Territory and New South Wales than in the other regions. Second trimester maternal serum screening was offered by 75% of hospitals with higher rates in Australian Capital Territory, South Australia and the lowest rate in Queensland. CONCLUSIONS: A high proportion of women are offered screening but with wide variation in the tests used.  相似文献   
992.
Effect of oestrogen replacement therapy on serum lipid profile   总被引:3,自引:0,他引:3  
BACKGROUND: Oestrogen deficiency in postmenopausal women alters the lipid metabolism unfavourably. AIM: To evaluate the effects of oral and transdermal oestrogen replacement therapy (ORT) on serum lipid profile. METHODS: Ninety hysterectomised and oophorectomised women were randomised into three equal groups (no hormones; oral conjugated equine oestrogen, 0.625 mg/day; transdermal oestradiol patches, 50 microg/day). Serum concentrations of total cholesterol, high-density lipoprotein (HDL) cholesterol, low-density lipoprotein (LDL) cholesterol and triglycerides were determined at the baseline and after 3 and 6 months of therapy. Student's t-test was used for statistical evaluation. RESULTS: Most of the hysterectomised women had abnormal serum lipid profile, especially HDL cholesterol levels (less than 40 mg/dL in 87%). A significant decline in the levels of serum cholesterol (total) as well as LDL and a significant increase in HDL cholesterol levels were observed following ORT by both modes, the response being comparatively rapid with oral route. After 3 and 6 months, the number of cases with HDL cholesterol levels above 40 mg/dL increased from initial 13 to 63% and 87% (oral) and 30 and 60% (transdermal), respectively. Serum triglyceride levels declined significantly with transdermal therapy but increased with oral ORT. CONCLUSIONS: Oestrogen replacement therapy either via oral or transdermal route has a beneficial effect on serum lipid profile of menopausal women. Whereas the oral route is more effective in increasing HDL cholesterol levels, the transdermal route is better for reducing the serum triglyceride level; hence, the latter should be the route of choice in women with high serum triglyceride levels.  相似文献   
993.
OBJECTIVE: To examine the relationships between peak serum estradiol (E(2)) levels and treatment outcome in in vitro fertilization (IVF) cycles after embryo transfer (ET) on day 3 or day 5. DESIGN: Retrospective analysis of 697 IVF-ET cycles between January 1999 and December 2001. SETTING: A university-affiliated assisted reproduction program. PATIENT(S): Infertile patients undergoing IVF-ET cycles. INTERVENTION(S): Peak E(2) concentration in serum was determined on the day of human chorionic gonadotropin (hCG) administration. The IVF-generated embryos were cultured for 2 days until transfer on day 3. If more than four 8-cell embryos were present on day 3, embryo culture was continued until day 5 for blastocyst transfer. MAIN OUTCOME MEASURE(S): Clinical pregnancy rates. RESULT(S): High peak E(2) levels did not adversely affect treatment outcome. After the cycles were divided according to the day of ET, high peak E(2) levels were associated with improved pregnancy rates after ET on day 5 but not on day 3. CONCLUSION(S): Increasing peak E(2) levels in IVF cycles are associated with improved pregnancy rates after ET on day 5.  相似文献   
994.
This chapter presents different means by which community initiatives have been undertaken to reduce the prevalence and incidence of genital and allied infections caused by Chlamydia trachomatis. As most of these infections in the majority of infected individuals do not produce symptoms that are likely to urge them to attend any health care unit, screening programmes are mandatory to be able to influence the epidemic of infections with this agent. In many societies there has been a skewed gender distribution in the number of chlamydia-positive persons; this probably indicates that diagnostic service activities have been directed more against one gender than the other. The important role of partner notification, as in the case of other sexually transmitted infections, has been documented. Different means of community initiative have included counselling of school children and groups of persons more likely to be infected. Counselling by the pharmacy has an important role in many societies. Selected cohorts have been offered - via the mass media, Internet, radio and television programmes - sampling kits which can be mailed to a laboratory for testing. The establishment of youth clinics has been found effective for detecting teenagers harbouring C. trachomatis, similarly to screening at antenatal clinics. The offer of free consultations, aetiological tests and therapy has been a part of community initiatives, mimicking the services offered for some of the classic sexually transmitted infections. This chapter considers the usefulness of different test methods and stresses the need to retest those found to be positive. Barriers to the successful introduction of screening activities and diagnostic services are also considered.  相似文献   
995.
Acknowledging urticaria as a symptom of mast cell degranulation is stressed. The biology of the mast cell, and the recognized immunologic and non-immunologic mast cell secretagogues are individually discussed, along with mechanisms of activation and mediators released. The major, preformed mediator histamine in the skin produces a prototypic, short-lived urticaria, however, the clinical spectrum and pattern of “hives” indicate that other mediators contribute to the polymorphism and variable behavior of this symptom. The clinical assessment is almost exclusively restricted to the history and physical examination. Features to review and examine are presented. The cause of “acute” urticaria is identifiable (by history) in the majority of patients, and except for hives that accompany an anaphylactic reaction, these patients rarely present to the physician for care. The persistent, or “chronic” hiver whose history cannot elicit a cause, is rarely triggered by an individual trigger, despite extensive professional evaluation. Evidence to support changing the chronological, “acute” and “chronic” classification of urticaria to “identifiable” and “non-identifiable” triggered urticaria is discussed, as is the futility of extensive, costly laboratory work-ups. The natural history of urticaria reveals that management should be directed toward allowing the patient to maintain an acceptable quality of life (with or without some urticaria), until the episode resolves.  相似文献   
996.
The purpose of this study was to evaluate the use of dried blood spots stored on filter paper as a means to provide specimens for virologic surveillance for measles virus (MV) in situations when the reverse cold chain is not available. Two single-step RT-PCR assays were evaluated for sensitivity of detection of MV nucleoprotein gene RNA. The more sensitive assay was then used to assess the stability of MV RNA in dried whole blood stored on filter paper. MV RNA was found to be stable in dried blood spots for up to 2 months at room temperature or 1 month at 37 degrees C. As few as 100 infected human peripheral blood mononuclear cells (PBMC) per blood spot could be detected using a single-step RT-PCR reaction and ethidium bromide detection. MV RNA was also detected in dried blood spots obtained from rhesus macaques after challenge with wild-type MV. In the rhesus samples, the single-step RT-PCR reaction could detect approximately 10(3) TCID(50) per blood spot, while nested PCR detected 3 TCID(50) per blood spot. The results of this laboratory-based study suggest that the use of dried blood spots stored on filter has the potential to improve virologic surveillance for MV in some areas, and they emphasize the need for continued testing under field conditions.  相似文献   
997.
The appropriate clinical use of serum iron and transferrin saturation (TSAT) requires satisfactory reference intervals from birth to old age, and for males and females. This study identified 54 publications from 1974 to 2001 that met the criteria used in three prior meta-analyses, and these were analyzed statistically. A summary of our review is presented along with our reference population data on these measurements. This analysis places previous publications in perspective and suggests possible reasons for the observed differences. Previous studies of the individual analytes, serum iron, transferrin, and TSAT values agree with the reference ranges presented in this study, although the entire experience over time and between sexes has not been available before. Our 95% reference ranges are somewhat broader than those of the smaller studies, but they agree well with those of the larger ones.  相似文献   
998.
OBJECTIVES: To determine the relationship between leptin and unintentional weight loss in older adults. DESIGN: Prospective cohort study over 2 years. SETTING: University-affiliated Veterans Affairs Medical Center. PARTICIPANTS: The subjects were 105 community-dwelling male veterans aged 65 and older who had participated in a prospective cohort study on nutrition and health conducted at the Veterans Affairs Puget Sound Health Care System from 1986 to 1989. MEASUREMENTS: Anthropometric data and fasting blood specimens were collected at baseline and annually for the subsequent 2 years. Stored blood specimens were analyzed for leptin, insulin, glucose, C-reactive protein, sex hormone binding globulin, and testosterone levels. RESULTS: Over 2 years, 75 men were weight stable (weight loss <4% of baseline) and 30 men had unintentional weight loss (weight loss>4% of baseline). The baseline body mass index (BMI) and leptin levels for the two groups were not statistically different. Positive correlations existed between leptin level and BMI at each time point for weight-stable and weight-loss subjects. Furthermore, a significant relationship existed between changes in leptin and changes in BMI over 1 year in multiple regression analysis (r =.436, P <.001 after the first year; and r =.630, P =.027 after the second year). CONCLUSIONS: Like in younger adults, plasma leptin levels remained proportional to BMI, and changes in BMI were accurately reflected by changes in leptin levels in older individuals. Fasting leptin levels did not predict involuntary weight loss over 2 years of follow-up.  相似文献   
999.
BACKGROUND: The apolipoprotein E polymorphism may influence the absorption of cholesterol from the intestine and thus the response of serum cholesterol to diet. We decided to use plant sterols to investigate this and studied whether the cholesterol-lowering effect of plant sterols differed between subjects with different apolipoprotein E genotyes. DESIGN: Thirty-one healthy subjects with the E3/4 or E4/4 genotype and 57 with the E3/3 genotype were fed sterol-enriched margarine or control margarine for 3 weeks each in a blind randomised cross-over design. The sterol margarine provided 3.2 g of plant sterols daily, was low-fat, and had the same fatty acid composition as the control margarine. Subjects used the margarines as part of their usual diet, which was fairly low in cholesterol (mean, 175 mg per day). The mean (+/- standard deviation) age of the subjects was 25 (+/- 11) years. RESULTS: The apolipoprotein E polymorphism did not significantly affect the responses of total and LDL cholesterol. The decrease in total cholesterol was 0.36 mmol L-1 (7.4%) in the E3/3 subjects and 0.31 mmol L-1 (5.7%) in the epsilon 4 subjects (P = 0.50) and that in LDL cholesterol was 0.34 mmol L-1 (12.2%) in the E3/3 subjects and 0.32 mmol L-1 (9.8%) in the epsilon 4 subjects (P = 0.68). CONCLUSION: The serum cholesterol response to plant sterols is not affected by the apolipoprotein E polymorphism in healthy subjects who consume a low-cholesterol diet.  相似文献   
1000.
Metamizol is an analgesic and antipyretic agent that can induce agranulocytosis in certain patients. However, its effects on granulocyte viability and differentiation have been poorly evaluated. Here we analysed the effects of metamizol and its active metabolite, 4-methylaminoantipyrine (MAA), on the viability of HL60 promyelocytes and their dimethyl sulphoxide-induced differentiated granulocytes. Metamizol and MAA at 75 microM (above the peak of plasmatic concentration after 2g intake) did not alter granulocytic differentiation of HL60 cells. Only at concentrations above 100 microM, well over the pharmacological range, metamizol-induced apoptosis in about 30% of the HL60 promyelocytes, while HL60-granulocytic terminally differentiated cells were more resistant to this apoptotic action. When the effects of metamizol were compared with those of acetylsalicylic acid (ASA) and diclofenac on cell viability, at equivalent concentrations used in analgesic and antipyretic therapy (75 microM for metamizol, and ASA and 3 microM for diclofenac) their apoptotic effects were similar. Again, the HL60 promyelocytes were more sensitive to apoptosis than granulocytic differentiated cells, as measured by the percentage of sub-G(1) cells detected by flow cytometry and by determination of caspase activity as a function of poly(ADP-ribose) polymerase cleavage. Furthermore, when human blood-derived granulocytes were treated with metamizol, MAA, and ASA at 75 microM or diclofenac at 3 microM, less than 10% of apoptotic granulocytes were detected, whereas at toxicological/suprapharmacological concentrations (10mM), about 90% of granulocytes were apoptotic. These results demonstrate that metamizol, MAA, ASA, and diclofenac, at pharmacological concentrations, neither affect the granulocytic differentiation process nor induce relevant apoptosis on terminally differentiated granulocytes.  相似文献   
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