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31.
Influences on prescribing in non-fundholding general practices.   总被引:2,自引:1,他引:2       下载免费PDF全文
BACKGROUND: The experience from general practice fundholding suggests that financial incentives may influence prescribing; guidelines and hospital prescribing are two other suggested influences. AIM: A study was undertaken to establish general practitioners' attitudes to a financial prescribing incentive scheme, the presence and use of guidelines, and the influence of prescribing initiated within secondary care. METHOD: A postal questionnaire survey of non-fundholding general practices in the former Northern Region was conducted. RESULTS: Practices' thinking and subsequent decisions about the incentive prescribing scheme were most often influenced by discussions within the practice (45%). Those practices that achieved their savings under the incentive scheme were less likely than those not achieving savings to feel that the target was not achievable, the time scale was unacceptable, and that the philosophy behind the scheme was unacceptable. Forty-five per cent of practices received advice from neither a medical nor a pharmaceutical adviser; 27% of practices received advice from both, 12% from a medical adviser only and 16% from a pharmaceutical adviser only. Of the practices that tried to make their target savings, 91% intended to increase generic prescribing; fewer than one-third of practices mentioned any other measure. Prescribing guidelines were reported by a minority of practices, although reported rates of use were high when these were present. Clinical guidelines for three conditions, asthma, diabetes and hypertension, were present in more than 50% of practices; 25% of practices had no clinical guidelines. Hospital prescribing was reported as 'always' or 'usually' influencing prescribing for diabetes by 57% of respondents, ischaemic heart disease by 55%, peptic ulceration by 49%, asthma by 42% and hypertension by 39%. CONCLUSIONS: General practitioner prescribing is influenced by a complex web of factors, with no single factor pre-eminent. To understand this area further, there is a need to take each of these areas and ascertain the match between doctors' perceptions and actual practice.  相似文献   
32.
Endothelin receptor expression in human decidua   总被引:3,自引:1,他引:3  
The endothelins are signalling peptides that act via two receptors, ET(A) and ET(B). In the human endometrium, endothelin receptors have been demonstrated in glands and stroma and have been shown to vary during the course of the menstrual cycle. The present study was undertaken to determine whether or not expression of endothelin receptors changes during pregnancy or after administration of exogenous progestagens. The expression of the receptors was correlated with the appearance of basement membrane components during decidualization of the endometrial stroma. Decidual specimens (n = 15) were obtained during the first trimester of pregnancy and 10 at term. Sixteen pairs of endometrial biopsies were obtained from women with menorrhagia before and after exposure to exogenous progestagens. A total of 15 hysterectomy specimens were used as controls for the expression of stromal basement membrane proteins in the absence of decidualization. Autoradiography was carried out with selective ligands for ET(A) ([125I]-PD 151242) and ET(B) ([125I]-BQ3020). The distribution of ligand binding was then compared with the distribution of laminin alpha2 light chain and collagen IV. ET(A), ET(B), laminin alpha2 light chain, and collagen IV were expressed in stromal decidual cells in the first trimester of pregnancy. ET(B) was also found on endometrial glandular epithelium. Quantitative macro-autoradiography and multiple regression analysis demonstrated a highly significant positive correlation (P < 0.001) between expression of ET(B) and laminin alpha2 light chain. In the third trimester qualitative examination suggested a reduction of ET(A) in the stroma. Progestagen-induced decidua exhibited a similar pattern to that found in first trimester decidua. This study has demonstrated up-regulation of ET(B) during the progesterone- dependent process of decidualization and suggests a paracrine or autocrine role for endothelins in the decidua.   相似文献   
33.
Permanent impairment of embryo development by hydrosalpinges   总被引:6,自引:9,他引:6  
Recent reports suggest a deleterious effect of hydrosalpinges on pregnancy outcome for in-vitro fertilization (IVF) and improvement following surgical treatment. We compared the effect of hydrosalpinx on pregnancy outcome in 286 patients having 348 IVF cycles and followed the development of untransferred embryos for 7 days to determine if hydrosalpinges affect oocyte quality or embryo development. The delivery rate per retrieval was significantly lower for patients with hydrosalpinx, but was restored by surgical treatment to that of patients without hydrosalpinx. However, the implantation rate per embryo transferred and normal blastulation of untransferred embryos, which were significantly decreased in patients with hydrosalpinx, and growth arrest and degeneration of untransferred embryos, which were significantly increased compared to patients without hydrosalpinx, were not restored by surgical treatment of hydrosalpinges. We conclude that surgical treatment of hydrosalpinges decreases early pregnancy loss and improves pregnancy outcome, possibly by diminishing reversible deleterious effects exerted on the endometrium. As we have seen in our laboratory, hydrosalpinges may have a permanent negative influence on ovarian function, follicular development and oocyte quality since implantation of transferred embryos and normal blastulation of untransferred embryos remain low, and in-vitro growth arrest and degeneration remain high despite surgical treatment of hydrosalpinges.   相似文献   
34.
The relationship between fecundability and month of birth was investigated in a cohort of 1526 women who married between 1802 and 1929, using only women whose first marriage occurred before the age of 35 years. On the basis of their time to pregnancy (TTP, calculated as time between wedding and first birth minus gestational length), women were categorized into two groups: fecunds (TTP up to 12 months or prenuptial conceptions, n = 1348) and subfecunds (TTP >18 months, n = 118). By use of logistic regression, cosinor functions with a period of 1 year or 6 months and variable shift and amplitude were fitted through the monthly odds of subfecunds versus fecunds. The best fitting curve was unimodal, with a zenith in September (P = 0.13 for H0: no differences). Exclusion of childless women (n = 36, minimum follow-up 5 years) from the subfecunds led to a similar curve (P < 0.01), while childless women, as compared with fecunds, showed a birth distribution that was best represented with a bimodal curve with zeniths in January and July (P = 0.06). This study provides evidence for the existence of differences in fecundability by month of birth. The cause of this relationship is unclear, but may lie in a melatonin-dependent circannual variability of the quality of the oocyte.   相似文献   
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BACKGROUND AND METHODS. Several conjugate vaccines against Haemophilus influenzae type b have been developed in the search for one that induces protection even in young infants. We evaluated the safety and efficacy of a conjugate vaccine that links the H. influenzae type b capsular polysaccharide to the outer-membrane protein complex (OMPC) of Neisseria meningitidis serogroup B. We conducted a double-blind, placebo, controlled trial in Navajo infants, who are at high risk for systemic infections caused by H. influenzae type b. The infants were randomly assigned to receive the first dose of vaccine or placebo at 42 to 90 days of age and the second at 70 to 146 days of age. RESULTS. Of the infants in the trial, 2588 were assigned to receive the vaccine and 2602 to receive placebo. The mean follow-up was 269 days in the vaccine group and 267 days in the placebo group. Before the age of 18 months, there was 1 systemic H. influenzae type b infection in the vaccine group, as compared with 22 in the placebo group (P less than 0.001; point estimate of efficacy, 95 percent; 95 percent confidence interval, 72 to 99 percent). Of the 22 H. influenzae type b infections in the placebo group, 13 were meningitis. Among the children who received both doses, there was 1 H. influenzae type b infection in the vaccine group (n = 2056) and 14 in the placebo group (n = 2105) (P less than 0.001; point estimate of efficacy, 93 percent; 95 percent confidence interval, 53 to 98 percent). The single infection in the vaccine group occurred at 15 1/2 months of age in an infant with osteomyelitis. Between the first and second doses there were no H. influenzae type b infections in the vaccine group and eight in the placebo group (P less than 0.005; point estimate of efficacy, 100 percent; 95 percent confidence interval, 41 to 100 percent). CONCLUSIONS. The H. influenzae type b OMPC vaccine, administered at 2 and 4 months of age, is safe and induces a high rate of protection against invasive disease caused by H. influenzae type b in infants under the age of 18 months. Protection begins after the first dose.  相似文献   
38.
PKD1 is the major locus of the common genetic disorder autosomal dominant polycystic kidney disease (ADPKD). Analysis of the predicted protein sequence of the human PKD1 gene, polycystin, shows a large molecule with a unique arrangement of extracellular domains and multiple putative transmembrane regions. The precise function of polycystin remains unclear with a paucity of mutations to define key structural and functional domains. To refine the structure of this protein we have cloned the genomic region encoding the Fugu PKD1 gene. Fugu PKD1 spans 36 kb of genomic DNA and has greater complexity with 54 exons compared with 46 in man. Comparative analysis of the predicted protein sequences shows a lower level of homology than in similar studies with identity of 40 and 59% similarity. However key structural motifs including leucine rich repeats (LRR), a C-type lectin and LDL-A like domains and 16 PKD repeats are maintained. A region of homology with the sea urchin REJ protein was also confirmed in Fugu but found to extend over 1000 amino acids. Several highly conserved intra- and extra- cellular regions, with no known sequence homologies, that are likely to be of functional importance were detected. The likely structure of the membrane associated region has been refined with similarity to the PKD2 protein and voltage gated Ca2+ and Na+ channels highlighted over part of this area. The overall protein structure has therefore been clarified and this comparative analysis derived structure will form the basis for the functional study of polycystin and its individual domains.   相似文献   
39.
Vascular endothelial growth factor (VEGF) is a potent regulator of vasculogenesis and tumour angiogenesis. We have investigated whether the VEGF -2578, -1154, +405 and +936 SNPs and associated haplotypes confer susceptibility to and/or influence prognosis in cutaneous malignant melanoma (CMM) skin cancer. A total of 152 CMM patients and 266 controls were genotyped for VEGF promoter SNPs by ARMS-PCR. Strong linkage disequilibrium between the -2578, -1154 and +405 SNPs was detected (association, rho = 0.488-0.965), but not between these SNPs and SNP +936 (association, rho = 0.004-0.130). No SNPs or three SNP haplotypes (-2578, -1154, +405) were significantly associated with CMM, although a number of non-significant trends were observed. However, the VEGF -1154 AA genotype and -2578, -1154, +405 CAC haplotype were both significantly associated with less advanced (Stage 1) disease (P = 0.03). In addition, the VEGF -1154 AA genotype was associated with thinner primary vertical growth phase tumours (P = 0.002), while VEGF -1154 GG was associated with thicker primary tumours (P = 0.02). These preliminary results indicate that VEGF genotype may influence tumour growth in CMM, possibly via the effects of differential VEGF expression on tumour angiogenesis.  相似文献   
40.
Levin  DC; Gardiner  GA  Jr 《Radiology》1987,164(3):675-680
For many years, atherosclerotic coronary artery lesions have been described by angiographers only in terms of location and degree of narrowing. However, it has become apparent that coronary stenoses generally have distinct morphologic features that can be recognized at angiography and that allow them to be classified as either "simple" or "complex" plaques. Complex plaques are those characterized by ulcerated or ruptured surfaces, subintimal hemorrhage, superimposed partially occluding thrombi, recanalized thrombi, or some combination. Pathologic studies have shown a very high frequency of these lesions at sites of total thrombotic occlusion of coronary arteries. Clinical and angiographic studies have demonstrated a high frequency of such lesions in living patients with both unstable angina and acute myocardial infarction. The presence of complex stenoses has also been found to increase the risk of future myocardial infarction. Plaque morphology thus appears to significantly affect the prognosis of patients with coronary disease and should be carefully evaluated in interpretation of all coronary angiograms.  相似文献   
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