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   13267篇
  免费   830篇
  国内免费   71篇
耳鼻咽喉   87篇
儿科学   209篇
妇产科学   90篇
基础医学   1945篇
口腔科学   343篇
临床医学   910篇
内科学   3699篇
皮肤病学   202篇
神经病学   834篇
特种医学   615篇
外科学   2160篇
综合类   54篇
一般理论   2篇
预防医学   373篇
眼科学   164篇
药学   836篇
中国医学   18篇
肿瘤学   1627篇
  2024年   67篇
  2023年   207篇
  2022年   318篇
  2021年   608篇
  2020年   320篇
  2019年   366篇
  2018年   455篇
  2017年   363篇
  2016年   399篇
  2015年   374篇
  2014年   452篇
  2013年   488篇
  2012年   761篇
  2011年   810篇
  2010年   427篇
  2009年   347篇
  2008年   624篇
  2007年   573篇
  2006年   527篇
  2005年   465篇
  2004年   465篇
  2003年   431篇
  2002年   428篇
  2001年   245篇
  2000年   250篇
  1999年   251篇
  1998年   134篇
  1997年   90篇
  1996年   93篇
  1995年   88篇
  1994年   69篇
  1993年   63篇
  1992年   220篇
  1991年   225篇
  1990年   187篇
  1989年   223篇
  1988年   195篇
  1987年   175篇
  1986年   165篇
  1985年   174篇
  1984年   129篇
  1983年   105篇
  1982年   50篇
  1981年   51篇
  1979年   113篇
  1978年   52篇
  1977年   48篇
  1975年   49篇
  1974年   47篇
  1973年   49篇
排序方式: 共有10000条查询结果,搜索用时 0 毫秒
21.
Hypertension after extracorporeal shock wave lithotripsy (ESWL) has been a controversial subject. Changes in blood pressure were studied in 262 patients (mean age 47.8 years) 18.6 months after ESWL. According to World Health Organization criteria the number of patients who showed a decrease exceeded those who showed an increase in blood pressure. The patients who have been on antihypertensive therapy showed a significantly greater decrease in blood pressure than those without medication. Of 192 normotensive patients diastolic pressure increased 1.2 mm. Hg and 2 (1.0%) had hypertension 18.4 months after ESWL. Annualized increase in diastolic pressure and new onset of hypertension were calculated to be 0.78 mm. Hg and 0.65%, respectively. Significant elevation of diastolic pressure was noted in the patients who received a larger number of shock waves. Blood pressure should be carefully followed after ESWL especially in patients who have been treated by a greater number of shock waves.  相似文献   
22.
Infective endocarditis of the mitral area accompanied by anorexia nervosa is extremely rare. A 34-year-old Japanese woman presented with high fever and a heart murmur that had developed over the previous 2-month period. Echocardiography revealed mitral regurgitation and vegetation attached to the anterior mitral leaflet, which had markedly prolapsed to the left atrium. We removed the vegetation with a small part of the anterior mitral leaflet and successfully repaired the mitral valve. The patient showed good recovery, and the mitral regurgitation and left ventricular chamber size had satisfactorily decreased at 2 months after the operation.  相似文献   
23.
The synthesis and structure-activity relationships of C-terminal octapeptide analogues of anaphylatoxin C5a have been studied. The introduction of hydrophobic amino acids into the N-acetylated native octapeptide (N-Ac-His-Lys-Asp-Met-Gln-Leu-Gly-Arg-OH) (1) has led to an analogue with 100 times more activity than the native octapeptide in inhibiting the binding of 125I-labeled anaphylatoxin C5a to human neutrophil membrane receptors. The observed apparent binding Ki's for the compounds (8-10) are in the range of 1-3 microM, and they possess nearly full agonist activity, despite the fact that these analogues are one-eighth or -ninth the size of the natural ligand anaphylatoxin C5a.  相似文献   
24.
To evaluate the clinical significance of scintigraphic overlap of thallium-201 (201T1) and technetium-99m pyrophosphate (99mTc), we observed 28 patients with acute myocardial infarction (AMI) in whom coronary reperfusion was attempted. All patients underwent dual energy emission computed tomography (D-ECT) on the third post AMI day which facilitated comparing 99mTc and 201T1 images from identical slices simultaneously. The scintigraphic results of the 28 patients were as follows: (table, see text) In conclusion, (1) significant 201T1 and 99mTc overlap on D-ECT suggest very early and successful reperfusion, and (2) none of the patients with unsuccessful reperfusion exhibits overlap.  相似文献   
25.
Thrombotic microangiopathy (TMA) may develop after living donor liver transplantation (LDLT), but the mechanism is not fully understood. We retrospectively analyzed all patients undergoing LDLT at our center, including TMA patients, to elucidate the clinical characteristics and presentation and to determine which patients have a higher risk of occurrence of TMA. In all, 57 adult patients were reviewed after LDLT at our institution. TMA was diagnosed by sudden and severe thrombocytopenia, followed by hemolytic anemia with fractionated erythrocytes in the blood smear. Clinical features were compared between the TMA group and the non-TMA group. Of the 57 patients, 4 were diagnosed with posttransplantation TMA. ABO blood group (ABO)-incompatibility, cyclophosphamide (CPA), and recipient blood group (type O) were closely correlated with the occurrence of TMA. Thrombocytopenia appeared 1 to 5 days before hemolytic anemia. Coagulative function markers stayed at the same level after TMA, while marked elevation was shown in fibrinolytic function markers such as plasminogen activator inhibitor type 1 (PAI-1). TMA occurred at a higher prevalence in ABO-incompatible graft recipients. Additional factors associated with ABO-incompatible transplantation, such as an overdose of immunosuppressants, may affect the likelihood of TMA. Sudden and severe thrombocytopenia presented before hemolytic anemia and the serum levels of PAI-1 correlated well with the clinical course of TMA. In conclusion, early recognition of thrombocytopenia and elevation of PAI-1 is crucial to diagnose TMA especially in ABO-incompatible LDLT.  相似文献   
26.
A 41-year-old man was hospitalized for further evaluation of an abnormal chest films which revealed a nodular shadow in the right middle lung field, which remarkably enlarged during one year. As no diagnostic procedures ruled out lung carcinoma of right S6, a right lower lobectomy was performed. Pathologically the nodules were composed of amorphous and eosionphilic materials which were diagnosed as amyloid by Congo-red stain and electron microscopic examination. Since there were no deposits in other organs and there was no abnormality of serologic and urinary protein analysis, a diagnosis of primary nodular pulmonary amyloidosis was established.  相似文献   
27.
Four symptoms of sequelae (abnormal synkinesis, facial spasm, contracture, and crocodile's tear) which persisted or appeared after 6 months from onset were examined with 351 patients with Bell's palsy. The incidence of sequelae were 2% in the group having score (May-Hosomi's modified method, 90 points method) over 40 points within 1 months after onset. Other hand, the incidence of sequelae were 15% in the group having score under 40 points at 1 weeks from onset, 30% in the group having score under 40 points at 2 weeks, 57% in the group having score under 40 points at 3 weeks, and 76% in the group having score under 40 points at 1 month. From these findings, it was seen that the prognostication with a high accuracy was possible by the score.  相似文献   
28.
This study was designed to explore the health status or quality of life (QOL) in 366 patients with rheumatoid arthritis in Japan. Physical, social, and emotional functions of the patients, namely the QOL, were measured by the modified health assessment questionnaire, the quality of well-being score, and the face scale, respectively. These functions were also evaluated by the new methods using visual analogue scales. The longer the duration of rheumatoid arthritis, the worse the QOL measures in these patients. A similar result was observed in the relationship between the stage classification of progression of rheumatoid arthritis and the QOL measures. In contrast, the traditional medical process measures, such as Lansbury activity index, sedimentation rate, and serum CRP concentration did not correlate with the duration of the disease. We conclude that the QOL measures in this study are useful for evaluation of the functional status and well-being of patients with rheumatoid arthritis. However, the clinical usefulness of these measures for evaluation of effectiveness and/or side effects of anti-rheumatic drugs still remains unknown.  相似文献   
29.
30.
A 17-year-old girl developed vomiting of sudden onset, followed by a state of confusion that progressed rapidly to coma within one day. Laboratory tests indicated iron deficiency anemia and reactive thrombocytosis, but there was no evidence of coagulopathy. There was no history of medication including the contraceptive pill, either. Emergency CT scan without contrast enhancement showed increased density along the course of the vein of Galen and internal cerebral veins. A repeated CT scan without contrast enhancement carried out 24 hours after the onset of the illness confirmed extensive bilateral hypodensity of the thalami, basal ganglia and adjacent white matter. There was also a prominent spontaneous increase in the density of the deep cerebral venous system. MRI was performed 3 days after the onset of the illness, which showed absence of a flow void in the region of the internal cerebral veins and septal veins on T1-weighed images. T2-weighted images showed low intensity in these veins. At autopsy, the bilateral internal cerebral veins were occluded by fresh thrombosis and hemorrhagic infarction was seen in the bilateral thalami.  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