首页 | 本学科首页   官方微博 | 高级检索  
文章检索
  按 检索   检索词:      
出版年份:   被引次数:   他引次数: 提示:输入*表示无穷大
  收费全文   113篇
  免费   4篇
耳鼻咽喉   1篇
儿科学   1篇
妇产科学   7篇
基础医学   27篇
临床医学   6篇
内科学   30篇
皮肤病学   1篇
神经病学   10篇
特种医学   6篇
外科学   12篇
综合类   1篇
预防医学   6篇
药学   3篇
肿瘤学   6篇
  2022年   6篇
  2021年   1篇
  2019年   2篇
  2018年   4篇
  2017年   2篇
  2015年   3篇
  2013年   8篇
  2012年   7篇
  2011年   3篇
  2010年   1篇
  2009年   3篇
  2008年   8篇
  2007年   6篇
  2006年   7篇
  2005年   6篇
  2004年   4篇
  2003年   5篇
  2002年   4篇
  2001年   2篇
  2000年   3篇
  1999年   2篇
  1998年   2篇
  1995年   2篇
  1993年   1篇
  1991年   1篇
  1990年   5篇
  1989年   4篇
  1988年   2篇
  1987年   2篇
  1986年   3篇
  1985年   1篇
  1984年   3篇
  1983年   2篇
  1979年   1篇
  1976年   1篇
排序方式: 共有117条查询结果,搜索用时 359 毫秒
1.
The effects of oral contraceptive administration on the social relationships of adult female cynomolgus monkeys (Macaca fascicularis) were examined. Ten females were administered ethinyl estradiol/ethynodiol diacetate (Demulen), 10 were administered ethinyl estradiol/norgestrel (Ovral), and 10 served as a control group. The monkeys lived in social groups of 5 females each, and patterns of social interaction and social status were recorded. Interfemale relationships were also observed when a vasectomized male was placed in each social group for 50 min, once/week. During the latter observations, preliminary data on the effects of oral contraceptive treatment on sexual interaction were also collected. In the absence of the male, interfemale agonistic interactions and time spent alone were influenced by social status but not by oral contraceptive treatment. Time spent in passive body contact, an affiliative state, was reduced by Ovral treatment. In the presence of the male, dominant females aggressively interfered with the sexual interactions of subordinates. This aggression resulted in the termination of a greater proportion of the sexual interactions of subordinates than dominants in the control group only, indicating suppression of this type of interaction by oral contraceptive treatment. Other effects included a decreased frequency of ejaculation with Ovral-treated females. These results suggest that oral contraceptives may suppress certain types of female agonistic behavior (e.g., in the context of mate competition) and some oral contraceptives may interfere with sexual activity. More broadly, these findings indicate that intrasexual competition for access to mates may occur in females as well as males. This study was supported in part by NICHD Contract #N01-HD-32800 and by Grant #HL14164 from the National Heart, Lung and Blood Institute.  相似文献   
2.
C G Hatjis  D R Koritnik  A Crews 《Endocrinology》1988,122(4):1455-1459
The effects of systemic administration of 17 beta-estradiol (E2) and progesterone (P) on the concentration and affinity of myometrial beta-adrenoreceptors were studied in non-pregnant, previously oophorectomized guinea pigs receiving a continuous infusion of E2, P, a combination of the two hormones, or placebo for 7 days. Myometrial beta-adrenoreceptors were characterized by using (-)-[125I-cyanopindolol as the specific beta-adrenoreceptor ligand. Compared to that in the control group, E2 administration resulted in a 7-fold increase in the density of myometrial beta-adrenoreceptors. Administration of P alone resulted in a significant increase in both beta-adrenergic receptor concentration and the receptor dissociation constant (Kd). Finally, a combination of E2 and P treatment did not result in any synergistic or additive effect for the beta-adrenergic receptors, while the Kd was twice that of the control or E2-treated animals. We conclude that systemic administration of these sex steroid hormones, directly or indirectly, modulates myometrial beta-adrenergic receptor concentrations and their ligand affinity.  相似文献   
3.
beta(2)-Glycoprotein I (beta(2)GPI) appears to be the major antigen for antiphospholipid antibodies (aPL) in patients with antiphospholipid syndrome (APS). In early infancy, virtually all children initiate transient immune response to non-pathogenic nutritional antigens, which fails to terminate in children with atopic diseases. To examine the possibility that a prolonged immune response to beta(2)GPI could also spread to the human protein, antibodies against human beta(2)GPI (anti-beta(2)GPI) were determined in 93 randomly selected children with different allergic diseases. A high frequency (42%) of IgG anti-beta(2)GPI was found in children with atopic dermatitis (AD), but not in those with other allergic diseases. Anti-beta(2)GPI in children with AD were exclusively of the IgG1 subclass and bound to bovine beta(2)GPI as well, but not to either beta(2)GPI combined with the phospholipid cardiolipin. The epitopes were identified in domain V of beta(2)GPI and the antibody binding was abolished upon the specific proteolytic cleavage of the phospholipid-binding C-terminal loop in domain V of beta(2)GPI. These results indicated that the epitopes for anti-beta(2)GPI in children with AD most likely resided in close vicinity of the phospholipid-binding site of beta(2)GPI. The epitopic difference from anti-beta(2)GPI in APS may explain presumed non-thrombogenicity of anti-beta(2)GPI in children with AD.  相似文献   
4.
Antiphospholipid syndrome (APS) has been defined as a clinical and laboratory entity. Laboratory criteria include the presence of anticardiolipin antibodies (aCL) and/or lupus anticoagulant (LA), collectively termed as antiphospholipid antibodies (aPL). However, there has been a rising interest in antibodies against so-called protein cofactors, particularly in beta(2)-glycoprotein I. In the early 90s, annexins were considered as target antigens for aPL, but at present the exact role of antibodies against annexins (aANX) remains puzzling. This review is concerned with annexin V or annexin A5 (ANXA5), a widespread member of the annexin family, and antibodies directed towards it. We have endeavoured to summarise essential information about the detection of anti-annexin V antibodies (aANXA5) and their clinical relevance. This review has also brought together some relevant published data concerning the structure, physiological role and therapeutic potential of ANXA5.  相似文献   
5.
Enhanced oxidative stress is involved in the progression of renal disease. Since angiotensin converting enzyme inhibitors (ACEI) have been shown to improve the antioxidative defence, we investigated, in patients with nondiabetic nephropathy, the short-term effect of the ACEI ramipril on parameters of oxidative stress, such as advanced glycation end products (AGEs), advanced oxidation protein products (AOPPs), homocysteine (Hcy), and lipid peroxidation products. Ramipril (2.5-5.0 mg/day) was administered to 12 newly diagnosed patients for 2 months and data compared with a patient group under conventional therapy (diuretic/beta-blockers) and with age- and sex-matched healthy subjects (CTRL). Patients had mild to moderate renal insufficiency and showed, in the plasma, higher fluorescent AGE and carboxymethyllysine (CML) levels, as well as elevated concentrations of AOPPs, lipofuscin and Hcy when compared with CTRL. Basal data of the patients on conventional therapy did not differ significantly from the ramipril group, except for higher Hcy levels in the latter. Administration of ramipril resulted in a drop in blood pressure and proteinuria, while creatinine clearance remained the same. The fluorescent AGEs exhibited a mild but significant decline, yet CML concentration was unchanged. The AOPP and malondialdehyde concentrations decreased, while a small rise in neopterin levels was evident after treatment. The mentioned parameters were not affected significantly in the conventionally treated patients. Evidence that ramipril administration results in a mild decline of fluorescent AGEs is herein presented for the first time. The underlying mechanism may be decreased oxidative stress, as indicated by a decline in AOPPs and malondialdehyde.  相似文献   
6.
Ferritin may play a direct role on the immune system. We sought to determine if elevated levels of ferritin in lupus patients correlate with disease activity and organ involvement in a large cohort. Ferritin levels (gender and age adjusted) were assessed in 274 lupus serum samples utilizing the LIASON Ferritin automated immunoassay method. Significant disease activity was determined if European Consensus Lupus Activity Index (ECLAM)?>?2 or Systemic Lupus Erythematosus Disease Activity Index (SLEDAI)?>?4. Utilizing an EXCEL database, we compared elevated ferritin levels to manifestations grouped by organ involvement, serology, and previous therapy. The patients were predominantly female (89%), median age was 37 years old, and disease duration was 10.6?±?7.7 years. Hyperferritinemia was found in 18.6% of SLE patients. Compared to subjects with normal ferritin levels, a significantly greater proportion of patients with hyperferritinemia had thrombocytopenia (15.4% vs. 33.3%, p?=?0.003) and lupus anticoagulant (11.3% vs. 29.0%, p?=?0.01). Additionally, compared to normoferritinemic subjects, hyperferritinemic subjects had significantly higher total aCL (99.7?±?369 vs. 30.9?±?17.3 GPI, p?=?0.02) and aCL IgM antibody levels (75.3?±?357.4 vs. 9.3?±?10.3 GPI, p?=?0.02), and marginally lower aCL IgG antibody levels (9.2?±?4.9 vs. 9.7?±?3.9 GPI, p?=?0.096). While the ECLAM score significantly correlated with hyperferritinemia (p?=?0.04), the SLEDAI score was marginally associated with hyperferritinemia (p?=?0.1). Serositis was marginally associated with hyperferritinemia, but not with other manifestations. An association with serologic APS was encountered. Hyperferritinemia was associated with thrombocytopenia, lupus anticoagulant, and anti-cardiolipin antibodies suggest that it may be an early marker for secondary antiphospholipid syndrome in SLE patients.  相似文献   
7.
8.
9.
BACKGROUND: There is no standard triage method for earthquake victims with crush injuries because of a scarcity of epidemiologic and quantitative data. We conducted a retrospective cohort study to develop predictive models based on clinical data for crush injury in the Kobe earthquake. METHODS: The medical records of 372 patients with crush injuries from the Kobe earthquake were retrospectively analyzed. Twenty-one risk factors were assessed with logistic regression analysis for three outcomes relating to crush syndrome. Two types of predictive triage models--initial evaluation in the field and secondary assessment at the hospital--were developed using logistic regression analysis. Classification accuracy, Brier score and area under the receiver operating characteristic curve (AUC) were used to evaluate the model. RESULTS: The initial triage model, which includes pulse rate, delayed rescue, and abnormal urine color, has an AUC of 0.73. The secondary model, which includes WBC, tachycardia, abnormal urine color, and hyperkalemia, shows an AUC of 0.76. CONCLUSIONS: These triage models may be especially useful to nondisaster experts for distinguishing earthquake victims at high risk of severe crush syndrome from those at lower risk. Application of the model may allow relief workers to better utilize limited medical and transportation resources in the aftermath of a disaster.  相似文献   
10.
Background – Hereditary spastic paraparesis (HSP) is a heterogeneous group of disorders characterized by progressive bilateral lower limb spasticity. Functional imaging studies in patients with corticospinal tract involvement have shown reorganization of motor circuitry. Our study investigates functional changes in sensorimotor brain areas in patients with HSP. Methods – Twelve subjects with HSP and 12 healthy subjects were studied. Functional magnetic resonance imaging (fMRI) was used to measure brain activation during right‐hand finger tapping. Image analysis was performed using general linear model and regions of interest (ROI)‐based approach. Weighted laterality indices (wLI) and anterior/posterior indicies (wAI and wPI) were calculated for predefined ROIs. Results and discussion – Comparing patients and controls at the same finger‐tapping rate (1.8 Hz), there was increased fMRI activation in patients’ bilateral posterior parietal cortex and left primary sensorimotor cortex. No differences were found when comparing patients and controls at 80% of their individual maximum tapping rates. wLI of the primary sensorimotor cortex was significantly lower in patients. Subjects with HSP also showed a relative increase in the activation of the posterior parietal and premotor areas compared with that of the primary sensorimotor cortex. Our findings demonstrate an altered pattern of cortical activation in subjects with HSP during motor task. The increased activation probably reflects reorganization of the cortical motor system.  相似文献   
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号