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31.
The transmembrane glycoprotein CD83 has been described as a specific maturation marker for dendritic cells and several lines of evidence suggest that CD83 regulates thymic T cell maturation as well as peripheral T cell activation. Here we show for the first time that CD83 is involved also in the regulation of B cell function. CD83 is up-regulated on activated B cells in vivo, specifically in the draining lymph nodes of Leishmania major-infected mice. The ubiquitous transgenic (Tg) expression of CD83 interferes with Leishmania-specific T cell-dependent and with T cell-independent antibody production. This defect is restricted to the B cell population since the antigen-specific T cell response of CD83Tg mice to L. major infection is unchanged. The defective immunoglobulin (Ig) response is due to Tg expression of CD83 on the B cells because wild-type B cells display normal antigen-specific responses in CD83Tg hosts and CD83Tg B cells do not respond to immunization in a mixed wild-type/CD83Tg bone marrow chimera. Finally, the treatment of non-Tg C57BL/6 mice with anti-CD83 mAb induces a dramatic increase in the antigen-specific IgG response to immunization, thus demonstrating a regulatory role for naturally induced CD83 on wild-type B cells.  相似文献   
32.
It has been suggested that psychophysiological measures of sensory and sensorimotor gating, P50 gating and prepulse inhibition of the startle reflex (PPI), underlie core features of schizophrenia and are linked to dopaminergic pathways in the striatum and prefrontal cortex. In the present study, the effects of a potent D2/D3 receptor antagonist, amisulpride, were investigated on PPI and P50 gating in a large sample of antipsychotic-naive, first-episode patients with schizophrenia. A total of 52 initially antipsychotic-naive, first-episode schizophrenia patients were assessed for their P50 gating, PPI, and habituation/sensitization abilities at baseline and after 2 and 6 weeks of treatment with flexible doses of amisulpride. In addition, 47 matched healthy controls were assessed at baseline and after 6 weeks. At baseline, the patients showed significantly reduced PPI, yet normal levels of P50 gating, habituation, and sensitization. Treatment with amisulpride showed no effects on these measures, either at 2 or 6 weeks of follow-up. This is the first study investigating the effects of monotherapy with a relatively selective dopamine D2/D3 receptor antagonist (amisulpride) on sensory and sensorimotor gating deficits in a longitudinal study of a large group of initially antipsychotic-naive, first-episode patients with schizophrenia. Our finding that amisulpride effectively reduced symptom severity in our patients without reducing their PPI deficits indicates that increased activity of dopamine D2 receptors may be involved in symptomatology of patients with schizophrenia, but not in their sensorimotor gating deficits.  相似文献   
33.
During August 2010–December 2012, we conducted a study of patients in Ghana who had Buruli ulcer, caused by Mycobacterium ulcerans, and found that 23% were co-infected with Mansonella perstans nematodes; 13% of controls also had M. perstans infection. M. perstans co-infection should be considered in the diagnosis and treatment of Buruli ulcer.  相似文献   
34.
It is urgent to develop efficacious HIV prevention programs to curb the reported extremely high HIV prevalence and incidence among transgender women (male-to-female transgender persons) who reside in large cities in the USA. This study aimed to describe unprotected receptive anal sex (URAS) and unprotected insertive anal sex (UIAS) among high-risk transgender women in relation to partner types, psychosocial factors, and background variables. Based on purposive sampling from the targeted communities and AIDS service organizations in San Francisco and Oakland, a total of 573 transgender women who had a history of sex work were recruited and individually interviewed using a structured survey questionnaire. Significant correlates with URAS with primary, casual, and commercial sex partners were found (e.g., needs for social support, frequency of social support received, exposure to transphobia, self-esteem, economic pressure, norms toward practicing healthy behaviors, and self-efficacy toward practicing safe sex). Multiple logistic regression analyses revealed that transgender women who had engaged in URAS with commercial partners were more likely to have higher levels of transphobia or lower levels of the norms or self-efficacy to practice safe sex. Among the participants who did not have vaginoplasty (preoperative transgender women), 16.4% had engaged in insertive anal sex (IAS) with commercial partners in the past 30 days. The participants who were HIV positive and had engaged in IAS were more likely to be African-American or Caucasians, coinfected with sexually transmitted infections, or identified themselves as homosexual. Practices of IAS among transgender women have not been thoroughly investigated in relation to sexual and gender identity. UIAS with homosexual and bisexual men in addition to URAS may be a cause for high HIV incidence among transgender women. An HIV prevention intervention study must be developed and evaluated, which aims to reduce HIV-positive and -negative transgender women's URAS and UIAS.  相似文献   
35.
36.

Background

Anastomotic leakage of esophagogastric and esophagojejunal anastomoses is a severe complication after esophagectomy and gastrectomy associated with a high mortality. We conducted this non-randomized observational study to evaluate the outcomes and clinical effectiveness of covered self-expanding stents (CSESs) in treating esophageal anastomotic leakage.

Methods

From 2002 to 2013, consecutive patients with anastomotic leakage after esophagogastrostomy or esophagojejunostomy who received CSESs were analyzed concerning leakage characteristics, leakage sealing rate, success and failure rates of CSES treatment, stent-related complications, and mortality.

Results

In 35 patients, anastomotic leakage originating from 5 cervical esophagogastrostomies, 6 thoracic esophagogastrostomies, 12 mediastinal esophagojejunostomies and 12 abdominal esophagojejunostomies were treated with 48 CSESs (16 fully CSES, 32 partially CSES). Of 35 patients, 24 received one stent, 9 received two consecutive stents, and 2 received three consecutive stents. Stent-related complications occurred in 71 % of patients (25/35). The most frequent complications were leakage persistence (44 %) and stent dislocation (19 %). Sealing of the anastomotic leakage was achieved in 24 (69 %) patients after a median (range) stenting time of 19 (1–78) days. Sealing rates differed significantly with 20 % (cervical esophagogastrostomies), 50 % (thoracic esophagogastrostomies), 92 % (mediastinal esophagojejunostomies) and 67 % (abdominal esophagojejunostomies) of patients (p = 0.023). Moreover, clinical success rates differed among these groups (60 vs. 67 vs. 92 vs. 58 %; p = 0.247). Clinical failure of stent treatment was more likely to be recognized in early postoperative leakage (median postoperative day 3 vs. 8; p = 0.098) compared with successful treatment, whereas no difference for clinical success rates was found comparing leakage ≤10 versus >10 mm (68 vs. 64 %; p = 0.479).

Conclusion

CSESs are an effective treatment for anastomotic leakage in patients with esophagogastrostomies and esophagojejunostomies. Best results can be achieved in patients with anastomotic leakages following mediastinal esophagojejunostomy, and in leakages occurring after the very early postoperative phase.  相似文献   
37.
The aim of this study was to characterize the subgroups of solitary fibrous tumor (SFT) and to investigate the expression of different biomarkers including CD34 and IGF2 in malignant transformation.  相似文献   
38.
Background: Statins, frequently prescribed in lipid‐lowering therapies, seem to have additional beneficial effects on periodontitis and tooth loss. If this is true, then chronic treatment with statins should also result in diminished tooth loss as a long‐term response. Methods: A 5‐year population‐based follow‐up study of tooth loss was performed comparing participants treated with statins (n = 134) with those not on the drugs (Study of Health in Pomerania). Negative binomial regression models were used to analyze the count variable of the outcome, including risk factors for tooth loss and measures of cholesterol metabolism. Results: When adjusted for age and sex, statins were associated with reduced tooth loss during the follow‐up period (incidence risk ratio [IRR] = 0.70, 95% confidence interval [CI] = 0.50 to 0.99, P = 0.04). When additionally adjusted for risk factors of periodontal breakdown, IRR was 0.72 (95% CI = 0.52 to 1.01). There was significant interaction with low‐density lipoprotein cholesterol (LDL‐c) at baseline. After stratification by LDL‐c, statins were associated with reduced tooth loss, resulting in IRR = 0.89 (95% CI = 0.44 to 1.83) and 0.64 (95% CI = 0.43 to 0.95), P = 0.03, at LDL‐c concentrations ≤100 mg/dL and >100 mg/dL (2.58 mmol/L), respectively. The data also showed reduced tooth loss associated with the 5‐year reduction in LDL‐c levels on a mmol/L basis and independently of statins (IRR = 0.87, 95% CI = 0.80 to 0.96, P = 0.004). Conclusion: Long‐term treatment with systemically administered statins may have the beneficial effect of protecting against tooth loss.  相似文献   
39.
Cognitive adaptation training (CAT) has been tested as a psychosocial treatment, showing promising results. To date there are no reported tests of CAT treatment outside the United States. Thus, we decided to adjust CAT treatment and apply it to an Integrated Treatment setting in Denmark. In this article we describe and discuss the feasibility of using CAT treatment in a randomized clinical trial in Denmark. The treatment period was shorter and the patients were instructed in prompting for specific actions by using newer tools such as schedules in their mobile phones. Social functioning, symptoms and quality of life were assessed using instruments validated in a Danish context. It was judged that, after some adjustments to fit the Danish assertive community treatment, CAT treatment was feasible in a Danish setting.  相似文献   
40.
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