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排序方式: 共有240条查询结果,搜索用时 31 毫秒
21.
Contraceptive potential of a mifepristone-nomegestrol acetate sequential regimen in women 总被引:1,自引:0,他引:1
Croxatto HB; Salvatierra AM; Fuentealba B; Massai R 《Human reproduction (Oxford, England)》1998,13(12):3297-3302
The effectiveness of a sequential regimen consisting of mifepristone, 10
mg/day for 15 days, followed by nomegestrol acetate (NOMA), 5 mg/day for
the next 13 days, for inhibiting ovulation and maintaining regular bleeding
cycles was assessed in 10 surgically sterilized volunteers who were
followed for one pretreatment and three treated cycles. Hormonal
determinations in blood and urine, ovarian ultrasonography, bleeding
records in all cycles and an endometrial biopsy taken on day 22-25 of the
third treatment cycle were used to monitor the effects of treatment. During
treatment, 24 monophasic (no sustained progesterone rise above 12 nmol/l)
and six biphasic cycles were recorded. Nine follicular ruptures were
detected echographically in these 30 treated cycles, five of which occurred
in monophasic cycles. All follicular ruptures occurred on days 1-7 of NOMA
treatment. Echographic and endocrine features of ovulatory cycles were both
present in only four treated cycles (13.3%). Development of a secretory
endometrium was achieved in all cases, but it was always irregular. Regular
withdrawal bleeding occurred in all subjects and no adverse reactions were
recorded. The ovarian and endometrial effects of this regimen justify
testing its contraceptive effectiveness in phase 2 clinical trials.
相似文献
22.
心房颤动的电生理重构 总被引:1,自引:1,他引:1
心房颤动 (atrial fibrillation,AF)是临床上最常见的一种持续性心律失常 ,其发病率随年龄而增加 ,40岁以下人群发病率约为 0 .2 %~ 0 .3% ,6 0~ 90岁年龄组发病率增至5 %~ 9% [1 ] 。新近 Framingham的研究表明 AF可以成为一种独立的因素使患者病死率增加 [2 ] 。 AF的发病机制尚未完全清楚 ,可能为非单一机制 ,普遍认为持续性 AF是由于心房内的多子波折返 ,每 1个折返环本身都在不停地改变其大小及传导方向。近年来 ,在 AF的基础及临床研究中 ,两个方面的进展具有十分重要的意义 :一是发现部分 AF起源于心房内某些部位如肺静脉口… 相似文献
23.
Kim WM; Merskey C; Deming QB; Adel HN; Wolinsky H; Clarkson TB; Lofland HB 《Blood》1976,47(2):275-286
Inbred Carworth Farms Nelson (CFN) congenitally hyperlipidemic rats had significantly shorter coagulation and prothrombin times and higher levels of coagulation factors, II, V, VII, VIII, and X than did controls. Conversely, congenitally hypolipidemic rats of the same strain had significantly longer coagulation and prothrombin times and lower levels of factors II, V, VII, X and XII and of blood platelets than did controls. A loop-shaped polyethylene cannula was inserted into the aorta to assess the potential for thrombosis. The hyperlipidemic group obstructed this significantly faster and the hypolipidemic group slower than did the controls. Normal CFN rats made hypertensive by unilateral renal artery clip developed hypertension together with significantly elevated serum cholesterol and factor VII and X levels. Rhesus monkeys with diet-induced hyperlipidemia showed shorter prothrombin times and higher factor X levels than did controls on normal diet. By selective breeding, two groups of squirrel monkeys were obtained. Both groups had similar serum cholesterol levels on a normal diet but one group (hyperresponders) showed higher serum cholesterol levels on a cholesterol-containing diet than did the other (hyporesponder) group. Both groups showed significantly elevated levels of factors II, V, VII, IX and X on a cholesterol-containing diet. There was good correlation between the levels of many coagulation factors and serum cholesterol in both rats and monkeys. If thrombosis is important in the genesis of atherosclerosis, these findings could indicate that elevation of plasma lipids may play a role, via the coagulation pathway, in the production of human vascular disease. 相似文献
24.
25.
Femke?DH?Koedijk Birgit?HB?van BenthemEmail author Eliane?MDC?Vrolings Wim?Zuilhof Marianne?AB?van der Sande 《Emerging themes in epidemiology》2014,11(1):12
Background
Men having sex with men (MSM) remain the largest high-risk group involved in on-going transmission of sexually transmitted infections (STI), including HIV, in the Netherlands. As risk behaviour may change with age, it is important to explore potential heterogeneity in risks by age. To improve our understanding of this epidemic, we analysed the prevalence of and risk factors for selected STI in MSM attending STI clinics in the Netherlands by age group.Methods
Analysis of data from the national STI surveillance system for the period 2006–2012. Selected STI were chlamydia, gonorrhoea, infectious syphilis and/or a new HIV infection. Logistic regression was used to identify factors associated with these selected STI and with overall STI positivity. Analyses were done separately for MSM aged younger than 25 years and MSM aged 25 years and older.Results
In young MSM a significant increase in positivity rate was seen over time (p?<?0.01), mainly driven by increasing gonorrhoea diagnoses, while in MSM aged 25 and older a significant decrease was observed (p?<?0.01). In multivariate analyses for young MSM, those who were involved in commercial sex were at higher risk (OR: 1.5, 95% CI: 1.2-1.9). For MSM aged 25 years and older this was not the case. Having a previous negative HIV test was protective among older MSM compared to those not tested for HIV before (OR: 0.8, 95% CI: 0.8-0.8), but not among younger MSM.Conclusions
MSM visiting STI clinics remain a high-risk group for STI infections and transmission, but are not a homogenous group. While in MSM aged older than 25 years, STI positivity rate is decreasing, positivity rate in young MSM increased over time. Therefore specific attention needs to be paid towards targeted counselling and reaching particular MSM sub-groups, taken into account different behavioural profiles.26.
Over the past decade, the unfortunate reality is that the income gap has widened between Canadian families. Educational outcomes are one of the key areas influenced by family incomes. Children from low-income families often start school already behind their peers who come from more affluent families, as shown in measures of school readiness. The incidence, depth, duration and timing of poverty all influence a child’s educational attainment, along with community characteristics and social networks. However, both Canadian and international interventions have shown that the effects of poverty can be reduced using sustainable interventions. Paediatricians and family doctors have many opportunities to influence readiness for school and educational success in primary care settings. 相似文献
27.
Cloning, functional activities and in vivo tissue distribution of rat NKR-P1+ TCR alpha beta + cells
Knudsen E; Seierstad T; Vaage JT; Naper C; Benestad HB; Rolstad B; Maghazachi AA 《International immunology》1997,9(7):1043-1051
We have successfully cloned nine NKR-P1+ TCR alpha beta + cells from PVG
rat spleens, utilizing murine macrophage inflammatory protein-1 alpha
(MIP-1 alpha) and IL-2. These clones are either double negative (DN,
CD4-CD8-), which included clones 3.31, 3.71, 4.19, 4.59 and 4.65, or single
positive (SP, CD4+CD8-), which included clones 1.64, 3.8, 3.76 and 3.78. No
CD8+ clone was recovered. All nine clones are restricted in terms of their
expression of the V beta antigens, since they express V beta 8.2 but not V
beta 8.5, V beta 10 or V beta 16. These clones are agranular and they fall
to generate NK or LAK activity upon incubation with IL-2, IL-12 or their
combination. On the basis of their production of intracellular cytokines
they can be divided into three categories: (I) SP clones (1.64, 3.8, 3.76
and 3.78) do not produce IL-2 or IL-4, but produce IFN-gamma and IL-12, and
they vary in their production of IL-1, RANTES or tumor necrosis factor
(TNF)-alpha; (II) DN clones 4.59 and 4.65 produce IL-1 alpha and IFN-gamma
only, and fall to produce other cytokines; and (III) DN clones 3.31, 3.71
and 4.19 produce IL-1 alpha, IL-1 beta, IL-2, IL-12, IFN-gamma, RANTES and
TNF-alpha. From all the clones examined only DN clones 3.31 and to a lesser
degree 4.19 produce IL-4. In vivo tissue localization of clones 3.8, 3.31
and 4.59 shows that these cells distribute into the liver and bone marrow
24 h post i.v. administration. Their accumulation in the liver and bone
marrow along with their ability to secrete various cytokines suggest that
these cells may influence the generation, differentiation or apoptosis of
immune or hematopoietic cells.
相似文献
28.
29.
Park CS Jeong HS Kim KB Han JH Chae HB Youn SJ Park SM 《Hepatobiliary & pancreatic diseases international : HBPD INT》2016,15(6):619-625
BACKGROUND: Acute cholangitis in old people is a cause of mortality and prolonged hospital stay. We evaluated the effects of methods and timing of biliary drainage on the outcomes of acute cholangitis in elderly and very elderly patients.METHODS: We analyzed 331 patients who were older than 75 years and were diagnosed with acute calculous cholangitis. They were admitted to our hospital from 2009 to 2014. Patients' demographics, severity grading, methods and timing of biliary drainage, mortality, and hospital stay were retrospectively obtained from medical records. Clinical parameters and outcomes were compared between elderly(75-80 years, n=156) and very elderly(≥81 years, n=175) patients. We analyzed the effects of methods [none, endoscopic retrograde cholangiopancreatography(ERCP), percutaneous transhepatic biliary drainage, or failure] and timing(urgent or early) of biliary drainage on mortality and hospital stay in these patients.RESULTS: Acute cholangitis in older patients manifested as atypical symptoms characterized as infrequent Charcot's triad(4.2%) and comorbidity in one-third of the patients. Patients were graded as mild, moderate, and severe cholangitis in 104(31.4%), 175(52.9%), and 52(15.7%), respectively. Urgent biliary drainage(≤24 hours) was performed for 80.5%(247/307) of patients. Very elderly patients tended to have more severe grades and were treated with sequential procedures of transient biliary drainage and stone removal at different sessions. Hospital stay was related to methods and timing of biliary drainage. Mortality was very low(1.5%) and not related to patient age but rather to the success or failure of biliary drainage and severity grading of the acute cholangitis.CONCLUSIONS: The methods and timing used for biliary drainage and severity of cholangitis are the major determinants of mortality and hospital stay in elderly and very elderly patients with acute cholangitis. Urgent successful ERCP is mandatory for favorable prognosis in these patients. 相似文献
30.
Genetic variation in HLA plays an important role in the pathogenesis of dermatomyositis (DM). The aim of this study was to investigate the association of HLA class II with DM in China. Two hundred and twenty‐four DM patients and 300 healthy controls were randomly enrolled at China‐Japan Friendship Hospital. High‐resolution typing of HLA‐DRB1 alleles was performed by sequencing based typing. The HLA‐DQA1 and HLA‐DQB1 alleles were determined by polymerase chain reaction sequence‐specific primers. The frequencies of HLA‐DRB1*09:01 (28.6% vs 11.3%, P < .0001, odds ratio, OR = 3.14, 95% confidence interval, CI = 2.47‐3.99) and HLA‐DRB1*12:01 (29.0% vs 11.0%, P < .0001, OR = 3.30, 95% CI = 2.59‐4.20) in DM patients were significantly higher than that in healthy controls. No significant difference was found in HLA‐DQA1 or DQB1 alleles between DM patients and healthy controls. Furthermore, DM patients with anti‐melanoma differentiation‐associated gene 5 antibody (anti‐MDA5) had a significantly higher frequency of HLA‐DRB1*12:01 compared to that for patients without anti‐MDA5 (P < .0001, OR = 4.77, 95% CI: 2.29‐9.93). Multivariate binary logistic regression analysis was performed to identify the risk factors for interstitial lung disease. The HLA‐DRB1*09:01 allele was a poor prognostic factor (P = .01, OR = 9.21, 95% CI: 1.47‐57.50) for DM patients with anti‐MDA5 autoantibody. In summary, our findings indicate that HLA‐DRB1*09:01 and HLA‐DRB1*12:01 alleles may contribute to susceptibility of adult DM in Han Chinese population. In addition, the DRB1*12:01 genotype is significantly associated with the presence of anti‐MDA5 antibody in DM patients. 相似文献