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61.
Breath-hold, contrast-enhanced, three-dimensional MR angiography   总被引:22,自引:0,他引:22  
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62.
交沙霉素在中国汉族、维吾尔族及哈萨克族中的药代动力学比较李国昌陈春雁杨明义(新疆石河子医学院第一附属医院药剂科,石河子832008;石河子农学院医院,石河子832003)为探讨交沙霉素(josamycin)在不同民族正常人体内过程,我们用相同的受...  相似文献   
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AIMS: To ascertain whether women who consulted their GP because they perceived themselves as at increased risk of familial breast cancer were indeed at increased risk, and to evaluate potential strategies for assessing genetic risk of breast cancer in general practice. METHODS: Sixty-seven out of 81 women who had consulted their GP for advice about their possible increased risk of developing breast cancer due to breast cancer in the family were interviewed. Familial breast cancer risk was assessed by a clinical geneticist. This assessment was compared with two recent guidelines for referral for genetic counselling. RESULTS: More than half (52%; n = 35) the women had a relative risk of two and over for developing breast cancer, while another half of these 35 (25%; n = 17) had a relative risk of three and over. All the women (n = 17) with a relative risk of three and over were identified by means of the two current guidelines for referral for genetic counselling, while more than half of the women (61%; n = 11) with a relative risk between two and three were identified. CONCLUSIONS: More than half the women concerned about their familial risk of breast cancer are indeed at increased risk of breast cancer. Current guidelines correctly identify women at high risk. However, doubts about the health gain and feasibility of referral warrant caution, and need further investigation.   相似文献   
64.
It now appears to be accepted that oestrogens and progestogens can help to prevent post-menopausal bone loss. This study accordingly evaluated vertebral bone mineral content (BMC) patterns and changes in calcitonin (CT) secretion in 12 women who had been ovariectomized in the previous 6 mth and in 12 others who had had a natural menopause, all of whom received oestrogen-progestogen replacement therapy for 12 mth. We also studied 12 oophorectomized and 21 normal-menopause women who did not receive any treatment and hence constituted the corresponding control groups.

A significant difference was found between the lumbar BMC in the treated women and the controls. Moreover, the CT levels rose significantly after replacement therapy in both the oophorectomized and the natural-menopause subjects. It was concluded that combined oestrogen-progestogen treatment can prevent post-menopausal bone loss and increase CT secretion.  相似文献   

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Saxton  HM; Borzyskowski  M; Mundy  AR; Vivian  GC 《Radiology》1988,168(1):147-150
Spinning top urethra (STU) is a term used to describe a widened posterior urethra seen mainly in girls. It is commonly regarded as a normal variant. The authors studied 30 girls with STU using videourodynamics. Twenty-eight showed bladder instability; 21, a congenital wide bladder neck anomaly; and 20, both instability and a wide bladder neck. One patient had a sensitive bladder. All patients had a urodynamic abnormality. The authors believe that the STU is nearly always an indication of bladder instability or wide bladder neck anomaly. The most common mechanism for the dilatation of the posterior urethra is that unstable contractions are resisted by a voluntary increase in distal sphincter tension so as to prevent leakage of urine. The resulting pressure rise produces distention of the posterior urethra, which will be maximal in subjects with a weak bladder neck mechanism as in the congenital wide bladder neck anomaly. The authors believe that STU is seldom if ever a normal variant.  相似文献   
67.
OBJECTIVE: A prospective, open-label, noncomparative, multicenter study was carried out in 163 women aged 18-39 (mean 25+/-5 years), who used an ultra-low-dose oral contraceptive pill (OCP) containing gestodene (GTD) 60 mug/ethinylestradiol (EE) 15 mug for 6 months. The objective of the study was to evaluate the acceptability, safety, bleeding patterns and premenstrual symptomatology in these women. METHODS: Patients used the OCP from Days 1-24, followed by a 4-day pill-free interval from Days 25-28 of the menstrual cycle. Physical and gynecological examinations were carried out at baseline and after 3 and 6 months, at which time blood pressure, weight, hemoglobin, hematocrit, SGOT, SGPT and urinalysis were also assessed. The Moos Menstrual Distress Questionnaire (MDQ) was completed on three consecutive days (Days 25-27 of the cycle) at baseline and at the end of the third and sixth cycles. Patients kept a menstrual diary throughout the study. RESULTS: A total of 146 women completed the study. Ten women discontinued because of adverse events and one undesired pregnancy occurred during treatment. No adverse metabolic effects were observed. The adverse event most frequently reported was breakthrough bleeding, which diminished, however, as the time of OC use increased. Cycle length and duration of bleeding decreased significantly with OC use (p<.01 and p<.05, respectively, after 6 months). Intensity of menstrual bleeding tended to decrease with OC use, but this difference was not statistically significant. Systolic and diastolic blood pressure were significantly lower after 6 months of OC use compared to baseline (p<.02). No alterations were recorded in body weight or laboratory evaluations. Statistically significant changes were found both in the total MDQ score and in several of the factors evaluated, and patients showed a statistically significant improvement in well-being with respect to premenstrual complaints and symptoms. CONCLUSION: This OC regimen is safe, well-accepted and well-tolerated, affects menstrual patterns beneficially by reducing both the intensity and duration of bleeding, provides good cycle control and improves premenstrual symptomatology.  相似文献   
68.
Recent studies of animal models have suggested that an increase in the number of T cells due to both peripheral expansion and increased thymic T cell output plays a key role in the regulation of bone loss after ovariectomy. Osteoclastogenic cytokines which are either produced by T cells or activate T cells have also been implicated in ovx induced bone loss. Among them are TNF alpha and IL-7. The present study investigates the role of thymectomy (THX) and IL-7 in bone metabolism in humans. We studied T cells subsets, cytokine production and bone metabolism in 13 women thymectomized for Myasthenia gravis as compared to healthy controls. Our data demonstrate that the number of CD4+ and TNF-producing T cells is lower in THX women as compared to euthymic controls. However in THX women the residual T cells produce higher levels of IL-7 and RANKL. Furthermore, flow cytometry shows that IL-7 is produced by T and B cells. Serum levels of TNF alpha were unaffected by THX and both serum TNF alpha and the RANKL/OPG correlated inversely with BMD. There were no differences in bone turnover and bone mineral density between THX women and the controls. These data suggest that THX decreases the number of TNF-producing CD4+ T cells but does not alters serum TNF levels. The RANKL/OPG ratio and indices of bone metabolisms are also not affected by THX, although THX increases the levels of IL-7 and RANKL. Further studies are needed to clarify the role of thymus in bone metabolism and osteoclastogenesis in postmenopausal women.  相似文献   
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