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   541篇
  免费   26篇
  国内免费   4篇
耳鼻咽喉   1篇
儿科学   21篇
妇产科学   3篇
基础医学   49篇
口腔科学   16篇
临床医学   92篇
内科学   101篇
皮肤病学   10篇
神经病学   86篇
特种医学   44篇
外科学   39篇
综合类   12篇
预防医学   46篇
眼科学   12篇
药学   22篇
肿瘤学   17篇
  2023年   2篇
  2021年   2篇
  2020年   3篇
  2019年   12篇
  2018年   10篇
  2017年   4篇
  2016年   7篇
  2015年   4篇
  2014年   15篇
  2013年   27篇
  2012年   29篇
  2011年   25篇
  2010年   30篇
  2009年   34篇
  2008年   33篇
  2007年   34篇
  2006年   29篇
  2005年   24篇
  2004年   22篇
  2003年   19篇
  2002年   9篇
  2001年   13篇
  2000年   11篇
  1999年   13篇
  1998年   14篇
  1997年   12篇
  1996年   12篇
  1995年   9篇
  1994年   7篇
  1993年   8篇
  1992年   15篇
  1991年   5篇
  1990年   10篇
  1989年   6篇
  1988年   6篇
  1987年   9篇
  1986年   5篇
  1985年   8篇
  1984年   2篇
  1983年   2篇
  1981年   2篇
  1980年   4篇
  1978年   2篇
  1948年   1篇
  1942年   3篇
  1937年   1篇
  1930年   1篇
  1929年   4篇
  1914年   2篇
  1885年   1篇
排序方式: 共有571条查询结果,搜索用时 16 毫秒
1.
Campylobacter jejuni (C. jejunj) infection is the most common antecedent in the axonal variant of Guillain‐Barré syndrome (GBS). Antibodies against nerve gangliosides found in GBS patients recognize cross‐reactive epitopes in the lipopolysaccharide (LPS) of C. jejuni. This led to the molecular mimicry hypothesis of GBS. We immunized eleven rabbits with a LPS extracted from HS:19 C. jejuni strain isolated from a patient with GBS and complete Freund's adjuvant (CFA)(group I). In a second experiment we immunized seven rabbits with LPS, CFA and keyhole limpet hemocyanin (KLH)(group II). All group I rabbits developed high titers of anti‐LPS, anti‐GM1, anti‐GD1b antibodies and lower titers of anti‐GD1a. One rabbit, 50 days after initial inoculation, showed tremor and weakness. All rabbits of group II developed high titres of antiganglioside antibodies and six animals showed weakness 59–113 days after initial inoculation. Two rabbits died. Pathology showed mild to moderate, tendentially grouped, axonal degeneration in sciatic nerves of four out of five animals. Control rabbits of group I (immunized with CFA only) did not develop antibodies, controls of group II (immunized with CFA + KLH) developed low titers of IgG anti‐GM1. None developed neurological signs or showed axonal degeneration. C. jejuni LPS is a potent B‐cell stimulator capable to induce a strong antiganglioside response in rabbits. However, to induce the neuropathy is crucial to employ KLH, a glycoprotein known to stimulate both humoral and cellular responses. This animal model reproduces the pathogenetic process hypothesized in axonal GBS with antiganglioside antibodies post C. jejuni infection.  相似文献   
2.
One of the first to permit multiple diagnoses, this new TMD classification scheme offers guidelines for clinicians and those conducting clinical field studies. The scheme was applied to a TMD population, with control subjects.  相似文献   
3.
Suture repair of a severed peripheral nerve is cumbersome, presents a focus for infection and neuroma formation, and does not always produce adequate stump alignment. An alternative form of repair is laser nerve welding, which is attractive because it does not introduce foreign material into the anastomotic site, it forms a circumferential seal, and it can be performed in difficult-to-reach areas. Laser repair has not been widely accepted both because the effect of laser irradiation on intact nerves is not well documented, and the anastomotic strength of the weld has been inferior to suture repair. In the first part of the present study, rat sciatic nerves were exposed and irradiated with increasing intensities from a Sharplan CO2 and KTP laser to document nerve damage as recorded by decreases in the peak compound action potential. A new technique of laser repair (S-Q weld) was then developed that involved harvesting subcutaneous tissue from the adjacent dermis, wrapping it around the two opposed nerve stumps, and lasering it to the epineurium to effect a weld. The strength of the S-Q weld (6.1 grams) was considerably greater than that produced by laser welding alone. The third phase of the study compared regeneration at 2 months in severed rat sciatic nerves repaired by either microsuture or S-Q weld. Analysis of the compound action potential values indicated that the number of regenerating fibers after laser repair was greater than that after suture repair, although a significant difference could not be demonstrated.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
4.
5.
Background: We have investigated the vascular perfusion of a wide variety of conditions of the anterior segment using fluorescein angiography.
Methods: The conditions were classified and findings reported according to the system set out below. Patients underwent full ocular examination. Fluorescein angiography of the anterior segment was carried out when indicated to investigate iris atrophy and neovascularisation. Specular microscopy of the corneal endothelium was used to detect changes in this tissue.
Results: The hypoperfusion was variable in degree and accompanied by varying degrees of iris hypoplasia and atrophy with neovascularisation. The degree of neovascularisation depended upon its rapidity of development, the pre-existing state of vascular perfusion and the underlying pathological condition.
Conclusions: Hypoperfusion with resultant ischaemia and neovascularisation is common in conditions of the anterior segment. An understanding of the changes is valuable in treating many conditions affecting the anterior segment. The changes observed may also occur elsewhere in the physical system and may be a significant part of the ageing process, either as scattered, disparate processes or as part of a general disease process.  相似文献   
6.
Postoperative radiation therapy in the management of lung cancer   总被引:1,自引:0,他引:1  
Postoperative radiation therapy for lung cancer is still controversial. In a 9-year period, 69 patients with non-oat-cell carcinoma of the lung (16% stage I, 26% stage II, and 58% stage III) received such therapy. The radiation dose was less than 5,000 cGy in 42 patients, 5,000-5,900 cGy in 16, and 6,000 cGy or more in 11; follow-up ranged from 24 to 64 months. Actuarial survival at 2 and 4 years was 50% and 16%, respectively, for squamous cell carcinoma, and 40% and 26% for adenocarcinoma. The 5-year survival for stages I, II, and III cancer was 29%, 17%, and 19%, respectively. Histologic findings and type of surgery did not affect survival, but the radiation dose apparently did. The 3-year survival for patients who received less than 6,000 cGy was 35%, compared with 73% for patients who received higher doses. In eight patients, treatment failed within the irradiated volume: all had received doses of less than 6,000 cGy, and the volume in three was judged to be inadequate.  相似文献   
7.
BACKGROUND: A randomized trial of a primary care-based intervention to prevent depression relapse resulted in improved adherence to long-term antidepressant medication and depression outcomes. We evaluated the effects of this intervention on behavioural processes and identified process predictors of improved depressive symptoms. METHOD: Patients at high risk for depression recurrence or relapse following successful acute phase treatment (N=386) were randomly assigned to receive a low intensity 12-month intervention or continued usual care. The intervention combined education about depression, shared decision-making regarding use of maintenance pharmacotherapy and cognitive-behavioural strategies to promote self-management. Baseline, 3, 6, 9 and 12-month interviews assessed patients' self-care practices, self-efficacy for managing depression and depressive symptoms. RESULTS: Intervention patients had significantly greater self-efficacy for managing depression (P<0.01) and were more likely to keep track of depressive symptoms (P<0.0001), monitor early warning signs (P<0.0001), and plan for coping with high risk situations (P<0.0001) at all time points compared to usual care control patients. Self-efficacy for managing depression (P<0.0001), keeping track of depressive symptoms (P=0.05), monitoring for early warning signs (P=0.01), engaging in pleasant activities (P<0.0001) and engaging in social activities (P<0.0001) positively predicted improvements in depression symptom scores. CONCLUSIONS: A brief intervention designed to target cognitive-behavioural factors and promote adherence to pharmacotherapy in order to prevent depression relapse was highly successful in changing several behaviours related to controlling depression. Improvements in self-efficacy and several self-management behaviours that were targets of the intervention were significantly related to improvements in depression outcome.  相似文献   
8.
PURPOSE. The purpose of this study is to identify the kinds of community organizations community leaders consider important for community health promotion efforts. DESIGN. Key informants were identified by reputational sampling of organizations relevant to community health promotion. Key informants were asked to list organizations they considered important for community health promotion. Differences in identified organizations were compared across informants from seven urban, five suburban, seven rural, and three Native American communities, with significance evaluated by chi-square tests. SETTING. This survey was conducted in 22 Western U.S. communities comprising the intervention and control communities of the Community Health Promotion Grants Program of the Henry J. Kaiser Family Foundation. SUBJECTS. Key informants (N = 184) from community organizations, identified using a reputational sampling technique beginning with the health department, were interviewed by telephone. MEASURES. Key informants listed organizations considered important for community health promotion in five areas: adolescent pregnancy, substance abuse, tobacco use, cancer, and cardiovascular disease. RESULTS. Informants frequently identified the health department (mentioned by 78% of informants overall), schools (72%), governmental agencies (55%), hospitals (47%), health clinics (42%), churches (33%), and newspapers (32%) as important. Organizations more prominent in urban and suburban areas than in rural and Native American areas included television stations, health-related private nonprofit organizations, substance abuse treatment centers, and colleges. Private physicians were frequently identified in rural areas (44% of informants).(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
9.
10.
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