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   589篇
  免费   31篇
  国内免费   1篇
耳鼻咽喉   1篇
儿科学   12篇
妇产科学   23篇
基础医学   90篇
口腔科学   34篇
临床医学   45篇
内科学   102篇
皮肤病学   2篇
神经病学   63篇
特种医学   34篇
外科学   142篇
综合类   1篇
预防医学   39篇
眼科学   1篇
药学   22篇
肿瘤学   10篇
  2022年   6篇
  2021年   13篇
  2020年   6篇
  2019年   12篇
  2018年   12篇
  2017年   12篇
  2016年   10篇
  2015年   9篇
  2014年   10篇
  2013年   24篇
  2012年   29篇
  2011年   43篇
  2010年   11篇
  2009年   22篇
  2008年   39篇
  2007年   37篇
  2006年   29篇
  2005年   21篇
  2004年   29篇
  2003年   19篇
  2002年   14篇
  2001年   11篇
  2000年   11篇
  1999年   11篇
  1998年   9篇
  1997年   7篇
  1996年   5篇
  1992年   13篇
  1991年   10篇
  1990年   4篇
  1989年   6篇
  1988年   7篇
  1987年   6篇
  1986年   9篇
  1985年   6篇
  1984年   7篇
  1983年   3篇
  1982年   3篇
  1981年   3篇
  1979年   6篇
  1977年   5篇
  1974年   8篇
  1973年   7篇
  1972年   7篇
  1971年   6篇
  1970年   8篇
  1969年   3篇
  1968年   5篇
  1967年   3篇
  1966年   3篇
排序方式: 共有621条查询结果,搜索用时 31 毫秒
61.
Sleep disturbance and bruxism are common clinical characteristics of the chronic facial pain patient. Previous studies have shown that chronic pain patients reporting disturbed sleep show more psychopathology and respond less readily to treatment. Bruxism has been linked to emotional stress and periods of difficult life change. The present study explored the question of whether sleep disturbance or bruxism are useful predictors of psychopathology in the facial pain population. Psychopathology was measured by using the Minnesota Multiphasic Personality Inventory (MMPI). It was predicted that facial pain patients who reported sleep disturbance or bruxism would correlate with more elevated scores on the MMPI profiles. The results of the study revealed a strong association between self-report of disturbed sleep and higher MMPI scores. No difference between the MMPI scores of bruxers and non-bruxers was found. It was concluded that sleep disturbance may be an effective predictor of psychological disturbance within the facial pain population, while bruxism was not found to be associated with psychological disturbance as measured by the MMPI.  相似文献   
62.

Objective  

In the current literature, there is a lack of detailed map of the origin, course and relationships of the medial tentorial artery (MTA) of Bernasconi–Cassinari often implicated in various diseases such as dural arteriovenous fistulas of the cranial base, stenotic lesions of the ICA, saccular infraclinoid intracavernous aneurysms and tentorial meningiomas.  相似文献   
63.
RATIONALE: Fibered confocal fluorescence microscopy (FCFM) is a new technique that produces microscopic imaging of a living tissue through a 1-mm fiberoptic probe that can be introduced into the working channel of the bronchoscope. OBJECTIVES: To analyze the microscopic autofluorescence structure of normal and pathologic bronchial mucosae using FCFM during bronchoscopy. METHODS: Bronchial FCFM and spectral analyses were performed at 488-nm excitation wavelength on two bronchial specimens ex vivo and in 29 individuals at high risk for lung cancer in vivo. Biopsies of in vivo FCFM-imaged areas were performed using autofluorescence bronchoscopy. RESULTS: Ex vivo and in vivo microscopic and spectral analyses showed that the FCFM signal mainly originates from the elastin component of the basement membrane zone. Five distinct reproducible microscopic patterns were recognized in the normal areas from the trachea down to the more distal respiratory bronchi. In areas of the proximal airways not previously biopsied, one of these patterns was found in 30 of 30 normal epithelia, whereas alterations of the autofluorescence microstructure were observed in 19 of 22 metaplastic or dysplastic samples, five of five carcinomas in situ, and two of two invasive lesions. Disorganization of the fibered network could be found on 9 of 27 preinvasive lesions, compatible with early disruptions of the basement membrane zone. FCFM alterations were also observed in a tracheobronchomegaly syndrome and in a sarcoidosis case. CONCLUSIONS: Endoscopic FCFM represents a minimally invasive method to study specific basement membrane alterations associated with premalignant bronchial lesions in vivo. The technique may also be useful to study the bronchial wall remodeling in nonmalignant chronic bronchial diseases.  相似文献   
64.
An inducible chloroplast gene expression system was developed in Chlamydomonas reinhardtii by taking advantage of the properties of the copper-sensitive cytochrome c(6) promoter and of the nucleus-encoded Nac2 chloroplast protein. This protein is specifically required for the stable accumulation of the chloroplast psbD RNA and acts on its 5' UTR. A construct containing the Nac2 coding sequence fused to the cytochrome c(6) promoter was introduced into the nac2-26 mutant strain deficient in Nac2. In this transformant, psbD is expressed in copper-depleted but not in copper-replete medium. Because psbD encodes the D2 reaction center polypeptide of photosystem II (PSII), the repression of psbD leads to the loss of PSII. We have tested this system for hydrogen production. Upon addition of copper to cells pregrown in copper-deficient medium, PSII levels declined to a level at which oxygen consumption by respiration exceeded oxygen evolution by PSII. The resulting anaerobic conditions led to the induction of hydrogenase activity. Because the Cyc6 promoter is also induced under anaerobic conditions, this system opens possibilities for sustained cycling hydrogen production. Moreover, this inducible gene expression system is applicable to any chloroplast gene by replacing its 5' UTR with the psbD 5' UTR in the same genetic background. To make these strains phototrophic, the 5' UTR of the psbD gene was replaced by the petA 5' UTR. As an example, we show that the reporter gene aadA driven by the psbD 5' UTR confers resistance to spectinomycin in the absence of copper and sensitivity in its presence in the culture medium.  相似文献   
65.
66.
67.
We report two patients who developed acquired factor V (FV) inhibitors not related to exposure to bovine thrombin. Associated conditions were found in one patient (surgery, antibiotic administration) but none in the other one. Bleeding complications occurred only in the patient with idiopathic FV inhibitor, leading to packed red cell infusion. Laboratory findings showed the presence of specific FV inhibitors with titers of 5.5 and 5 Bethesda units, respectively. These two patients received high-dose intravenous immunoglobulin and FV levels normalized within a few days with a concomitant disappearance of FV inhibitors.  相似文献   
68.
69.
A correlative imaging study was carried out in 61 female patients previously treated for ovarian carcinoma. Upon suspicion of recurrence, abdominopelvic immunoscintigraphy (IS) using F(ab')2 fragments of indium-111-labelled OC 125 monoclonal antibody was performed in all patients, Ultrasonography (US) and computed tomography (CT) were performed 53 and 37 times, respectively. The diagnostic accuracy of the different imaging techniques was studied per site (abdomen and pelvis) and per patient. The diagnostic accuracy of planar scintigraphy (PS) was slightly lower than that of emission computed tomography (ECT): 66% vs 73% for abdomen, 65% vs 72% for pelvis, and 78% vs 84% in analysis per patient. The accuracy of IS (PS and ECT combined) was markedly better than that of US and CT for abdomen (IS = 73%; US = 30%; CT = 47%), pelvis (IS = 73%; US = 37%; CT = 52%) and analysis per patient (IS = 85%; US = 43%; CT = 59%). The results of IS and morphological imaging techniques (MIT: US and/or CT) were correlatively analysed with the frequency of recurrence. When IS and MIT were both negative, the frequency of non-recurrence was 14/23 for abdomen, 7/12 for pelvis and 8/13 in analysis per patient. On the other hand, when both IS and MIT were positive, the frequency of recurrence was high (9/9 for abdomen, 17/21 for pelvis and 24/26 for analysis per patient). It was also found that a positive IS associated with a negative MIT was still highly suggestive of recurrence (17/21 for abdomen, 16/22 for pelvis and 17/19 for analysis per patient).(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
70.
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