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   750篇
  免费   37篇
耳鼻咽喉   3篇
儿科学   1篇
妇产科学   6篇
基础医学   117篇
口腔科学   15篇
临床医学   47篇
内科学   187篇
皮肤病学   2篇
神经病学   45篇
特种医学   12篇
外科学   109篇
预防医学   9篇
眼科学   13篇
药学   106篇
中国医学   3篇
肿瘤学   112篇
  2023年   2篇
  2022年   10篇
  2021年   12篇
  2020年   5篇
  2019年   6篇
  2018年   9篇
  2017年   10篇
  2016年   6篇
  2015年   7篇
  2014年   14篇
  2013年   26篇
  2012年   31篇
  2011年   36篇
  2010年   20篇
  2009年   17篇
  2008年   35篇
  2007年   26篇
  2006年   22篇
  2005年   22篇
  2004年   24篇
  2003年   48篇
  2002年   46篇
  2001年   33篇
  2000年   33篇
  1999年   27篇
  1998年   9篇
  1997年   9篇
  1996年   14篇
  1995年   3篇
  1994年   8篇
  1993年   5篇
  1992年   21篇
  1991年   30篇
  1990年   23篇
  1989年   21篇
  1988年   11篇
  1987年   19篇
  1986年   14篇
  1985年   11篇
  1984年   16篇
  1983年   7篇
  1982年   2篇
  1981年   3篇
  1980年   4篇
  1979年   6篇
  1978年   3篇
  1977年   7篇
  1974年   4篇
  1972年   2篇
  1966年   3篇
排序方式: 共有787条查询结果,搜索用时 62 毫秒
1.
We report the development of a serodiagnostic method for Mycobacterium avium complex (MAC) disease with an enzyme immunoassay (EIA) with the MAC-specific glycopeptidolipid (GPL) core as the antigen. In this study, we confirmed by EIA that the GPL core antibody was in the sera of immunocompetent patients with MAC disease. The EIA for quantifying the GPL core antibody was evaluated as a clinical tool for serodiagnosis of pulmonary MAC disease. A significant increase in GPL core antibodies (immunoglobulins G, A, and M) was detected in sera of patients with MAC pulmonary diseases when they were compared to patients who were colonized with MAC, patients with Mycobacterium kansasii disease or tuberculosis, and healthy subjects. The sensitivities and specificities of the GPL core-based EIA for diagnosis of MAC pulmonary disease were 72.6% and 92.2%, respectively, for IgG, 92.5% and 95.1%, respectively, for IgA, and 78.3% and 91.0%, respectively, for IgM. The best sensitivity and specificity were obtained by measuring immunoglobulin A antibodies against GPL core antigen. The level of GPL core antibodies reflected disease activity, since it decreased in cured MAC patients who had responded to chemotherapy. Measurement of serum antibodies against GPL core is useful for both diagnosis and assessment of disease activity in MAC disease of the lung.  相似文献   
2.
3.
Among 43 men more than 60 years old who complained of urinary irritative symptoms 40 had subclinical lesions in the brain on magnetic resonance imaging (MRI). Of these 40 patients 23 (57.5%) had detrusor hyperreflexia. The mean age of the patients with and without detrusor hyperreflexia was 75.8 and 68.2 years, respectively, which is a statistically significant difference. Patients with detrusor hyperreflexia were more likely to have lesions of the basal ganglia than patients without detrusor hyperreflexia. This study suggests that detrusor hyperreflexia, subclinical MRI lesions in the brain and aging are intimately interrelated.  相似文献   
4.
We were able to produce two highly reproducible experimental models (in the rabbit) that demonstrated a high degree of reflex bladder contractile activity. In one model, a somatovesical reflex was induced by touching or pinching the perineal area. This reflex may be organized through a neurogenic reflex at the spinal level. In another model, rhythmic bladder contractions were produced by distal urethral constriction in the absence of bladder distension. These rhythmic contractions were thought to be due to a supraspinal reflex. In both types of contractile reflexes, intravenous administration of hexamethonium inhibited the reflex contractile activity virtually completely, intravenous atropine inhibited over 90% of the induced contractile activity, thus suggesting that these contractions were mediated reflexly through cholinergic stimulation. These two models of reflex bladder contractions should be useful for the study of hyperreflexic bladders.  相似文献   
5.
We have prospectively analyzed three antigens for serodiagnosis of tuberculosis (TB). These antigens were tuberculous glycolipid antigen, lypoarabinomannan polysaccharide antigen, and antigen 60 (A60), which was derived from purified protein derivatives. Of the 131 patients with active pulmonary TB, 57 were both smear and culture negative and 14 had chronic active pulmonary TB that remained smear positive for >12 months of chemotherapy. One hundred twenty healthy adults were controls. The percentages of patients positive in all three tests were 58.8% for smear-positive active pulmonary TB and 71.4% for chronic active pulmonary TB. When the results of the three serodiagnostic tests were evaluated in combination, the sensitivity increased to 91.5% in patients with active pulmonary TB and to 86.0% in smear- and culture-negative patients. The false-positive rate of the three-test combination was 12.5% in the healthy control groups. In conclusion, it was not possible to detect all of the antibodies against antigenic substances in the cell walls of the tuberculous bacilli in the sera of all TB patients by using available serodiagnostic tests. However, the combined use of tests with three separate antigens maximizes the effectiveness of serodiagnosis.  相似文献   
6.
We report the development of a serodiagnostic method for Mycobacterium avium complex (MAC) disease with an enzyme immunoassay (EIA) with the MAC-specific glycopeptidolipid (GPL) core as the antigen. In this study, we confirmed by EIA that the GPL core antibody was in the sera of immunocompetent patients with MAC disease. The EIA for quantifying the GPL core antibody was evaluated as a clinical tool for serodiagnosis of pulmonary MAC disease. A significant increase in GPL core antibodies (immunoglobulins G, A, and M) was detected in sera of patients with MAC pulmonary diseases when they were compared to patients who were colonized with MAC, patients with Mycobacterium kansasii disease or tuberculosis, and healthy subjects. The sensitivities and specificities of the GPL core-based EIA for diagnosis of MAC pulmonary disease were 72.6% and 92.2%, respectively, for IgG, 92.5% and 95.1%, respectively, for IgA, and 78.3% and 91.0%, respectively, for IgM. The best sensitivity and specificity were obtained by measuring immunoglobulin A antibodies against GPL core antigen. The level of GPL core antibodies reflected disease activity, since it decreased in cured MAC patients who had responded to chemotherapy. Measurement of serum antibodies against GPL core is useful for both diagnosis and assessment of disease activity in MAC disease of the lung.  相似文献   
7.
Prolactin-releasing peptide (PrRP) was found to be a novel hypothalamic peptide that stimulates prolactin release in vitro and in vivo. In the normal adult rat brain, PrRP neurons are known to be located in only three areas, i.e. the dorsomedial hypothalamic nucleus, ventrolateral reticular formation; and nucleus of the tractus solitarius in the medulla oblongata. These PrRP neurons project neurites into various brain areas, including regions such as the paraventricular nucleus, supraoptic nucleus, and bed nucleus of the stria terminalis. Both PrRP nerve fibers and a high level of PrRP receptor, UHR-1, mRNA are observed in the area postrema (AP),but no PrRP neurons are detected in the AP of normal rats. In this study, we clearly demonstrated that PrRP-producing cells newly appeared in the AP of adrenalectomized rats by in situ hybridization and immunocytochemistry. Our results suggest that PrRP may have some important roles in the AP of adrenalectomized rats. This is the first report demonstrating the appearance of PrRP-positive cells in the AP.  相似文献   
8.
AIMS: To investigate the relation between localised amyloidosis and immunocytic dyscrasia. METHODS: Open lung biopsy specimens from a 72 year old man with multiple nodules in the right middle and lower lung were stained with haematoxylin-eosin, Congo red, and antibodies against IgG, IgA, IgM, and kappa and lambda light chains. Semi-nested PCR amplification for the immunoglobulin heavy chain (IgH) gene was performed using consensus primers for the VDJ region of the IgH gene, FR3A, LJH, and VLJH. RESULTS: The biopsy specimens contained eosinophilic amorphous material stained with Congro red and anti-kappa light chain, and surrounded by inflammatory cells intermingled with plasma cells. Plasma cells in the adjacent amorphous material showed cytoplasmic staining with anti-kappa. Polymerase chain reaction revealed a discrete amplified band of apparently uniform size with background smear. CONCLUSIONS: Primary AL type localised amyloidosis involves local accumulation of monoclonal plasma cells and their secreted products, as in nodular cutaneous amyloidosis. Localised AL type nodular amyloidosis is a separate entity in amyloidosis.  相似文献   
9.
We studied the expression of cell cycle regulators and growth factor-receptor systems in gastric carcinoma in young adults and tried to clarify the specific alterations associated with H. pylori. We studied 33 young patients (18-29 years old, mean age 26.4) with gastric carcinoma. The patients were classified into two groups according to the degree of atrophic gastritis. Then we examined the expression of p53, cripto, cyclin-E, c-met, c-erbB2 and TGF-alpha immunohistochemically and compared the results between the two groups. The results were compared with 66 sex-, tumor histology-, and depth-matched elder controls (36-86 years old, mean age 64.0). H. pylori was judged by Giemsa staining. Seventeen patients had atrophic changes in the corpus (Group A), while 16 showed superficial gastritis or normal mucosa (Group S). All 17 patients of Group A showed H. pylori infection, while the 3 of the 16 members of Group S did not have H. pylori. p53 overexpression was observed more frequently in Group S (88%) than in Group A (41%, p<0.05). In the 3 patients without H. pylori infection, all carcinoma specimens showed p53 overexpression. Overexpression of cyclin-E was detected in 4 patients from Group S. On the other hand, cripto was observed more frequently in Group A than in Group S. No obvious differences were observed in c-erbB2, TGF-alpha and c-met expression. Overall, p53 overexpression was detected more frequently in younger than in older patients, whereas cripto expression was less detected. These results suggest that p53 and cyclin-E may act in an H. pylori-independent or -adjunctive manner for gastric carcinogenesis. Cripto expression might be correlated tightly with H. pylori infection.  相似文献   
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