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   1600篇
  免费   183篇
  国内免费   3篇
耳鼻咽喉   7篇
儿科学   144篇
妇产科学   39篇
基础医学   381篇
口腔科学   19篇
临床医学   110篇
内科学   327篇
皮肤病学   19篇
神经病学   176篇
特种医学   53篇
外科学   153篇
综合类   18篇
预防医学   173篇
眼科学   5篇
药学   105篇
中国医学   1篇
肿瘤学   56篇
  2021年   16篇
  2018年   21篇
  2017年   14篇
  2016年   20篇
  2015年   24篇
  2014年   20篇
  2013年   55篇
  2012年   40篇
  2011年   53篇
  2010年   25篇
  2009年   27篇
  2008年   50篇
  2007年   56篇
  2006年   60篇
  2005年   48篇
  2004年   46篇
  2003年   34篇
  2002年   53篇
  2001年   28篇
  2000年   39篇
  1999年   44篇
  1998年   22篇
  1997年   23篇
  1993年   19篇
  1992年   42篇
  1991年   34篇
  1990年   35篇
  1989年   39篇
  1988年   40篇
  1987年   51篇
  1986年   49篇
  1985年   38篇
  1984年   23篇
  1983年   24篇
  1982年   15篇
  1979年   24篇
  1978年   18篇
  1977年   22篇
  1976年   23篇
  1975年   16篇
  1974年   16篇
  1973年   19篇
  1972年   28篇
  1971年   23篇
  1970年   17篇
  1933年   13篇
  1931年   13篇
  1924年   26篇
  1923年   21篇
  1922年   25篇
排序方式: 共有1786条查询结果,搜索用时 0 毫秒
1.
Die Anaesthesiologie - Auch wenn für Anästhesiologen über Jahrzehnte die Prophylaxe und Therapie postoperativer Schmerzen im Rahmen des postoperativen Patientenkomforts an vorderster...  相似文献   
2.
A case study of a family referred for clarification of cultural issues illustrates how a transcultural psychiatric service developed in the pediatric hospital setting can be used to advantage. A Vietnamese family with an inherited disorder. Mucopolysaccharidosis type VI (Maroteaux-Lamy syndrome, MPS VI), resisted genetic counseling and contraception. Three out of their six children were affected, one with a fatal outcome. The transcultural consultation offered an understanding of their behavior and facilitated subsequent management.  相似文献   
3.
Rabbits were exposed to submicrometer sulfuric acid mist at 1 mg/m3 for 1 hr to assess effects on alveolar region clearance of a polystyrene latex tracer aerosol. Bronchopulmonary lavage was performed at selected times after exposure for functional characterization of alveolar macrophages. In vivo, clearance was accelerated in acid exposed animals relative to sham controls. Acid exposure produced no change in the viability or numbers of macrophages recovered. Although an increase in the number of polymorphonuclear leukocytes, primary neutrophils, was observed by 1 hr in both acid and sham groups, compared to nonexposed controls, levels were normal by 12 hr in shams but continued elevated in the acid group through 24 hr. Reduced in vitro macrophage adherence was observed after acid exposure. In vivo uptake of the tracer particles by macrophages was enhanced during the first 3 hr after acid exposure and in vitro phagocytosis by polymorphonuclear leukocytes was increased through 48 hr post-exposure. The results indicate some functional alterations in free cells after in vivo exposure to H2SO4 and the production of a mild inflammatory response. This latter was associated with an acceleration of inert particle clearance from the alveolar region.  相似文献   
4.
Introduction As many as one quarter of all cancer survivors report traumatic stress symptoms from cancer-related experiences. While the majority of these patients do not meet the criteria for posttraumatic stress disorder (PTSD), there is growing evidence that subsyndromal symptoms can significantly contribute to functional impairment and negative health outcomes. Treatment options for the hallmark symptoms of traumatic stress—unpleasant, intrusive thoughts and avoidant behaviors—have not been well investigated for the cancer survivorship population. Materials and methods Seven female cancer survivors with traumatic stress symptoms from cancer-related experiences and no other major psychopathology, were enrolled to receive three sessions of Neuro-Emotional Technique (NET), a brief, targeted treatment that combines traditional desensitization principles with complementary modalities. Results Psychological outcome measures (Impact of Event Scale (IES) and Subjective Units of Distress (SUD) and physiological measures (Heart Rate (HR) and Skin Conductance Level (SCL) demonstrated the following changes: 71% on IES, 88% SUD, 74% on HR, and 65% on SCL following the intervention. Statistically significant changes were observed for all four parameters, and effect size g for proportion improved were 0.50 each for IES, SUD, and HR, and 0.20 for SCL. Conclusions These cases suggest feasibility of the NET intervention for cancer-related traumatic stress and the potential for change in symptoms and physiological reactivity. Further investigation is needed to determine the specific and long-term effects of such an approach. Implications for cancer survivors Traumatic stress from cancer-related experiences might represent a constellation of symptoms that are amenable to brief, targeted interventions. This study was supported by the O.N.E. Research Foundation  相似文献   
5.
The biological response to ambient air pollution may be a function of specific combinations of pollutants. Groups of rabbits were exposed to NO2 (0.3 ppm or 1 ppm) with and without H2SO4 (0.5 mg/m3) for 2 hr/day for up to 14 days for assessment of effects upon mucociliary clearance of tracer particles from the tracheobronchial tree. Exposure to NO2 did not alter clearance, while exposure to H2SO4 produced a retardation toward the middle of the exposure series. The combination of 0.3 ppm NO2 with H2SO4 resulted in a speeding of clearance, while no change from control was seen with the mixture employing 1 ppm NO2 with acid. These results emphasize the importance of performing studies with pollutant mixtures, since it is not always possible to extrapolate responses from studies examining effects of individual pollutants.  相似文献   
6.
For almost three decades, many have regarded general hospital psychiatric units as the most appropriate setting for acute treatment of persons with serious mental illness who were once treated mostly in state hospitals. The extent to which this transfer has taken place and the differences between public and private general hospitals have been unclear. Using data from the 1988 National Mental Health Facilities Study and published data from the 1970s, the authors found that nearly half of all general hospitals providing psychiatric services treat persons with serious mental illness. Significant differences in case and payer mix were observed between public and private general hospitals, although these differences were smaller than in the 1970s. The findings suggest increased involvement by private general hospitals in treating patients reimbursed by public payers, but the findings also indicate that persons with serious mental illness and those using Medicaid are still more prevalent in public general hospitals than in private ones.  相似文献   
7.
Despite improved survival after liver transplantation (OLTX) in HIV-positive individuals treated with highly active antiretroviral therapy (HAART), some transplant candidates do not survive to OLTX. To determine if pretransplant outcome is related to severity of liver disease and/or HIV infection, we prospectively evaluated 58 consecutive HIV-positive candidates seen at a single center from 1997-2002. Of the 58, 15 (25.9%) were transplanted, whereas 21 (36.2%) died before OLTX, a median one month of evaluation, with more than half of those (12 of 21, 57.1%) dying from infection. By contrast, of 1,359 HIV-negative candidates, 860 (63.3%) were transplanted, whereas 211 (15.5%) died before OLTX (P < 0.001). The cumulative survival following initial evaluation was significantly shorter among HIV-positive than HIV-negative candidates (880 vs. 1,427 days, P = 0.035, Breslow) but was not related to the initial pretransplant MELD score (16 vs. 15), INR (1.5 vs. 1.5), creatinine (1.3 vs. 1.3 mg/dL), or total bilirubin (6.6 vs. 5.7 mg/dL), respectively, all P > 0.05. Among untransplanted HIV-positive candidates, the 21 who died did not differ from the 22 surviving in initial MELD (15 vs. 13), CD4 (230 vs. 327/microL), HIV load (both < 400 copies/mL), HAART intolerance (10/21, 47.6% vs. 10/22, 45.4%), or HCV infection (16/21, 76.2% vs. 16/22, 72.3%), all P > 0.05. Further, the 21 did not differ from the 15 transplanted in pre-OLTX CD4, HIV load, or MELD score, all P > 0.05. In conclusion, pretransplant survival appears shorter in HIV-positive OLTX candidates and is unrelated to severity of liver or HIV disease. Further study is warranted to determine risk factors for poorer pretransplant outcomes.  相似文献   
8.
The objective of the study was to compare the clinical outcomes at the short-term follow-ups of two novel transobturator mid-urethral sling procedures – the transobturator tape (TOT) procedure and the tension-free vaginal tape (TVT)-obturator procedure. The study cohort consisted two groups of 40 women with urodynamically proven stress urinary incontinence (SUI). The patients in one group underwent the TOT procedure, performed according to Delorme (Prog Urol 11:1306–1313, 2001); those in the second group underwent the TVT-obturator operation, performed according to de Leval (Eur Urol 44:724–730, 2003). Intra-operative diagnostic cystoscopy was not performed with either the TVT-obturator or the TOT procedures. The average follow-up was 12 months. The two patient groups were similar in terms of demographic and therapeutic criteria, except for patient age, which was significantly younger in the TVT-obturator group. Previously reported TVT-related operative complications, such as bladder penetration, intra-operative bleeding, field infection and post-operative pelvic floor relaxation, were not observed in patients of either group. Bowel and urethral injuries were also not recorded. The therapeutic failure rates were 10% for the TOT procedure and 5% for the TVT-obturator procedure. Urinary frequency and urgency post-operatively were reported in 25% of the TOT patients and 19% of the TVT-obturator patients, pelvic or vaginal pain affected 10% of the TOT and 5% of the TVT-obturator patients, while post-operative voiding difficulty was experienced by 12.5% of the TOT and 7.5% of the TVT-obturator patients. None of the above-mentioned differences between the two patient groups were of statistical significance. The TVT-obturator and TOT procedures, both minimally invasive, novel, mid-urethral sling procedures, seem to be safe, easy-to-perform and effective in treating female SUI. The patients of both study groups suffered less intra- and post-operative surgical complications than previously been reported in connection with the TVT operation. The TVT-obturator patients had fewer therapeutic failures, less post-operative urinary frequency and urgency, less pelvic pain and less voiding difficulty. All of these findings, however, had no statistical significance; consequently, long-term comparative data collection will be required before solid conclusions can be drawn on the superiority of either of these two operative techniques.  相似文献   
9.
The antineoplastic properties of suramin, a polyanionic agent with demonstrated antigrowth factor activity, are under evaluation in vitro, in vivo, and in clinical trials. Suramin has been shown to have antitumor activity in patients with advanced, hormone refractory prostate cancer. During these trials, significant resolution of osseous pain was observed in nearly three quarters of the patients treated with suramin. To evaluate the effect of suramin on bone cells, we studied the effect of suramin on bone resorption in a neonatal mouse calvarial assay. Suramin inhibited bone-resorbing activity in a dose-related fashion and had an additive effect with calcitonin. Calvaria pretreated with suramin had less bone-resorbing activity, fewer attached osteoblasts, and less medium alkaline phosphatase activity than control calvaria. Suramin also inhibited osteoclastic release of tritiated proline from labeled bone in a dose-dependent fashion. The effect of metastatic prostate carcinoma on bone is incompletely understood, but may be moderated by tumor-produced factors and/or cytokines. The effects of several such agents, therefore, were examined in combination with suramin. Bone resorption induced by PTH, epidermal growth factor, tumor necrosis factor, and a tumor-produced factor, PTH related-protein, was blocked by suramin. The ability of suramin to inhibit the bone-resorbing effects of several cytokines suggests that its mechanism may involve direct action on bone metabolism. Autoradiography performed on calvaria treated with labeled suramin demonstrated heavy deposition of suramin on the outer surface of the matrix, adjacent to osteoblasts and osteoclasts lining the outer table, suggesting that bone cells may be subject to high local concentrations of the drug, in keeping with this hypothesis.  相似文献   
10.
In this report, we give details of two families in which fixed subaortic stenosis was found in more than one member. It is rare for this entity to show familial incidence.  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