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   2994篇
  免费   73篇
  国内免费   15篇
耳鼻咽喉   37篇
儿科学   27篇
妇产科学   19篇
基础医学   339篇
口腔科学   25篇
临床医学   191篇
内科学   729篇
皮肤病学   25篇
神经病学   206篇
特种医学   188篇
外科学   589篇
综合类   19篇
预防医学   71篇
眼科学   72篇
药学   165篇
肿瘤学   380篇
  2024年   7篇
  2023年   22篇
  2022年   63篇
  2021年   90篇
  2020年   45篇
  2019年   48篇
  2018年   61篇
  2017年   73篇
  2016年   60篇
  2015年   54篇
  2014年   70篇
  2013年   114篇
  2012年   182篇
  2011年   197篇
  2010年   103篇
  2009年   100篇
  2008年   152篇
  2007年   165篇
  2006年   189篇
  2005年   170篇
  2004年   153篇
  2003年   146篇
  2002年   152篇
  2001年   68篇
  2000年   53篇
  1999年   56篇
  1998年   40篇
  1997年   44篇
  1996年   33篇
  1995年   22篇
  1994年   21篇
  1993年   18篇
  1992年   25篇
  1991年   24篇
  1990年   30篇
  1989年   20篇
  1988年   33篇
  1987年   22篇
  1986年   21篇
  1985年   21篇
  1984年   9篇
  1983年   8篇
  1982年   10篇
  1981年   11篇
  1980年   7篇
  1978年   8篇
  1977年   8篇
  1975年   11篇
  1973年   9篇
  1971年   5篇
排序方式: 共有3082条查询结果,搜索用时 62 毫秒
41.
Background  Few studies of treatment of lateral ankle ligament rupture have given careful consideration to the activity levels of patients. In the present study, we investigated whether a patient’s activity level influences the outcome of the treatment of lateral ankle ligament rupture and whether treatment should be determined according to activity level. Methods  A total of 115 consecutive patients with lateral ankle ligament rupture were treated with short-term cast immobilization followed by functional bracing. We divided preinjury activity levels and activity levels at follow-up into four classes according to the International Knee Documentation Committee standards. Follow-up examination 1 year after injury included clinical assessment (anterior drawer test, range of motion, maximum circumference of the calf, tenderness, swelling), reinjury assessment, and functional evaluation by means of the Karlsson scoring system. Results  We found significant differences in ankle stability and reinjuries between the four groups classified by their preinjury activity level. The number of patients with ankle instability and reinjury was significantly higher in the high-activity group than in the low-activity groups. We also found significant difference between groups classified by activity level at follow-up with regard to the Karlsson score. Conclusions  The outcome of treatment of lateral ankle ligament rupture is significantly influenced by the patient activity level, and treatment may need to be determined according to this activity level.  相似文献   
42.
Seventeen patients treated for infected grafts (11/17) or aneurysms (6/17) of the aorta between 1998 and 2003 were reviewed to evaluate our experience with aortic infection. The causative organisms were identified in 12 patients (71%), with 5 (29%) having methicillin-resistant Staphylococcus aureus. A periaortic abscess occurred in eight patients, and all of them were associated with infected grafts. Surgical treatment included cryopreserved allograft replacement in eight patients, prosthetic graft replacement in four patients, and drainage with or without omental wrapping in five patients. One patient was still hospitalized at the end of the study period. Five patients with infected grafts died after the operation during the initial hospitalization. No early mortality occurred in the aneurysm group. The early mortality rate was 31% for all patients, 50% for the graft group, and 63% for patients with a periaortie abscess. Another patient with an infected aneurysm died of arrhythmia after discharge from the initial hospitalization, Ten patients are still alive without evidence of reinfection. The early mortality rate for patients with infected aortic grafts is higher than that for those with infected aneurysms, especially when a periaortic abscess accompanies them. However, the late outcome is favorable, with no reinfection or late treatment-related deaths.  相似文献   
43.
OBJECTIVE: The risk of stroke caused by dislodgment of loose atheromatous plaque or mural emboli is increased by cross-clamping of the aorta. Some patients undergo descending thoracic aortic aneurysm repair with proximal aortic cross-clamping between the left common carotid artery and the left subclavian artery. The objective of this study was to determine the influence of proximal aortic cross-clamping in arteriosclerotic aneurysm or dissecting aneurysm repair. METHODS: Between May 1984 and May 2003, 81 patients underwent elective surgery for distal arch or descending aortic aneurysm repair with proximal aortic cross-clamping between the left common carotid artery and the left subclavian artery. To evaluate the influence of the proximal aortic cross-clamping, patients were divided into two groups: patients who had undergone arteriosclerotic aneurysm repair (group I, n=25) and patients who had undergone dissecting aneurysm repair (group II, n=56). RESULTS: Eight (9.9%) of the 81 patients had a stroke. Six strokes occurred in operations for arteriosclerotic aneurysm repair group I and two strokes occurred in operations for dissecting aneurysm repair group II (24 vs 3.6%; p=0.009). In-hospital mortality rates were 12% in group I and 8.9% in group II (p=0.70). Major postoperative complications included renal failure requiring hemodialysis (in 4.2% of the patients in group I and in 8.3% of the patients in group II, p=0.99) and pulmonary complication (in 20% of the patients in group I and in 16% of the patients in group II, p=0.67). CONCLUSION: Cross-clamping between head vessels should be avoided if at all possible when operating on patients who have arteriosclerotic descending thoracic aneurysms.  相似文献   
44.
45.
BACKGROUND: Our previous study suggested a significant association between Ureaplasma urealyticum and nongonococcal urethritis (NGU). However, association of the serovars of U. urealyticum with NGU remains unclear. A polymerase chain reaction (PCR)-based assay can distinguish 4 serovars of Ureaplasma parvum from each other and categorize 10 serovars of U. urealyticum into 3 subtypes: subtype 1 (serovars 2, 5, 8, and 9), subtype 2 (serovars 4, 10, 12, and 13), and subtype 3 (serovars 7 and 11). GOAL: The goal of this study was to determine which subtypes of U. urealyticum are associated with NGU as determined by PCR-based assay. STUDY: The prevalence of U. urealyticum subtypes in 106 ureaplasma-positive men with urethritis was compared with that in 30 ureaplasma-positive men without urethritis. RESULTS:: In men with nonchlamydial NGU and men with Mycoplasma genitalium-negative nonchlamydial NGU, only U. urealyticum subtype 1 (serovars 2, 5, 8, and 9) was detected significantly more often than in men without urethritis. CONCLUSION: This study suggests that subtype 1 of U. urealyticum (serovars 2, 5, 8, and 9) is associated with NGU independently of Chlamydia trachomatis or M. genitalium.  相似文献   
46.
Intracellular events in retinal glial cells exposed to ICG and BBG   总被引:2,自引:0,他引:2  
PURPOSE: To investigate the intracellular events in retinal glial cells exposed to indocyanine green (ICG) and brilliant blue G (BBG). METHODS: The human Müller cell line MIO-M1 was exposed to a low dose (0.25 mg/mL) and a clinical dose (2.5 mg/mL) of ICG and a clinical dose (0.25 mg/mL) of BBG for 15 minutes, respectively. To quantify the proliferation and viability of the cells, [(3)H]-thymidine incorporation was measured and cell numbers were counted 24 hours after treatment. Cell morphology was evaluated using phase-contrast microscopy and transmission electron microscopy. The effects of ICG and BBG on phosphorylation of p38 MAPK and cleavage of caspase-9 and caspase-3 were examined by Western blot. RESULTS: ICG and BBG significantly reduced [(3)H]-thymidine incorporation in MIO-M1 cells compared with the vehicle-treated controls (P < 0.01). Cell number significantly decreased after exposure to ICG at 2.5 or 0.25 mg/mL (P < 0.01) but did not decrease after exposure to BBG at 0.25 mg/mL. Transmission electron microscopy revealed apoptotic changes only in the ICG-treated cells. Prominent p38 MAPK phosphorylation was observed in the presence of ICG, even at the low concentration and within a short time exposure; however, no apparent enhancement was observed in the presence of 0.25 mg/mL BBG. Furthermore, ICG, but not BBG, induced the cleavage of caspase-9 and caspase-3, which was inhibited by an inhibitor of p38 MAPK. CONCLUSIONS: ICG is toxic to retinal glial cells because it induces apoptosis, involving induction of the caspase cascade through p38 MAPK phosphorylation. In contrast, BBG does not cause apoptosis and thus could be a safer adjuvant during vitreoretinal surgery.  相似文献   
47.
S Okuda  K Motomura  T Sanai  Y Oh  K Onoyama  M Fujishima 《Nephron》1988,50(4):345-350
To investigate the effect of phosphate binder on adriamycin (ADR)-induced nephropathy, serial changes in renal histology and renal hemodynamics were compared between ADR rats treated with aluminum hydroxide (ADR-AH group) and those without AH (ADR group) for 24 weeks. Urinary protein excretion was less marked in the ADR-AH group than in the ADR group. Serum creatinine in the ADR group increased progressively from week 20, while in the ADR-AH group the increase was less. There were no significant differences in glomerular filtration rate or renal plasma flow between the both groups until week 12 but these parameters decreased to the significantly lower levels at week 24 in the ADR group. Vacuolative degeneration in glomerular epithelium, which was determined as an initial renal lesion, was more marked in the ADR group compared to the ADR-AH group. Glomerular sclerosis and tubulointerstitial changes developed progressively in the ADR group at the later stages. These changes were lessened in the ADR-AH group. In conclusion, AH prevents the progress in ADR-induced nephropathy. The beneficial effects appeared as the preservation of glomerular epithelial cells.  相似文献   
48.
The effect of dietary protein restriction on the progress of renal dysfunction was investigated in rats with adriamycin (ADR)-induced progressive glomerular disease. Dietary protein was reduced from 20% (normal diet) to 5% (low protein) immediately after (ADR-0w), 8 weeks (ADR-8w) or 16 weeks (ADR-16w) after the repeated injection of ADR. In the unrestricted (ADR-UR) group rats were fed 20% of protein throughout the 24-week experiment. Massive urinary protein developed immediately after ADR injection and significantly decreased by reducing dietary protein in all the groups (ADR-0w, ADR-8w, ADR-16w). However, plasma protein and serum albumin were low irrespective of the improvement of urinary protein. BUN and serum creatinine were unchanged in ADR-0w and ADR-8w groups, while they were increased in ADR-16w and ADR-UR groups. Glomerular sclerosis and tubular atrophy were much less severe in ADR-0w and ADR-8w than in ADR-16w and ADR-UR groups. The results indicate that dietary protein restriction checks the further progress of renal dysfunction. The importance of the time when protein intake should be reduced is discussed.  相似文献   
49.
Corynebacterium propinquum, which is included in Corynebacterium group ANF-3, exists as a commensal in the oral flora. This organism has not yet been fully recognized as a respiratory pathogen. We previously reported that the first case with respiratory infection caused by C. propinquum. On the other hand, Corynebacterium pseudodiphtheriticum is recognized as a causative organism in respiratory infections. Recently we experienced two cases with C. propinquum respiratory infections in our hospital. Three types of the onset such as a community-acquired infection, a hospital-acquired infection, and a nursing home acquired infections were observed. Our analysis indicated that gram staining of the purulent sputum is an essential tool to evaluate whether C. propinquum is a respiratory pathogen or not, because this organism is a commensal bacteria.  相似文献   
50.
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