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   15110篇
  免费   910篇
  国内免费   285篇
耳鼻咽喉   304篇
儿科学   154篇
妇产科学   120篇
基础医学   2741篇
口腔科学   219篇
临床医学   1363篇
内科学   3635篇
皮肤病学   462篇
神经病学   987篇
特种医学   719篇
外科学   1832篇
综合类   113篇
现状与发展   2篇
预防医学   603篇
眼科学   191篇
药学   1515篇
中国医学   256篇
肿瘤学   1089篇
  2024年   10篇
  2023年   120篇
  2022年   449篇
  2021年   690篇
  2020年   312篇
  2019年   422篇
  2018年   479篇
  2017年   374篇
  2016年   566篇
  2015年   723篇
  2014年   937篇
  2013年   1005篇
  2012年   1620篇
  2011年   1463篇
  2010年   824篇
  2009年   662篇
  2008年   891篇
  2007年   912篇
  2006年   707篇
  2005年   705篇
  2004年   519篇
  2003年   467篇
  2002年   391篇
  2001年   208篇
  2000年   196篇
  1999年   151篇
  1998年   82篇
  1997年   62篇
  1996年   32篇
  1995年   29篇
  1994年   31篇
  1993年   25篇
  1992年   28篇
  1991年   23篇
  1990年   28篇
  1989年   16篇
  1988年   23篇
  1987年   13篇
  1986年   13篇
  1985年   18篇
  1984年   10篇
  1983年   9篇
  1982年   7篇
  1981年   7篇
  1980年   4篇
  1979年   8篇
  1976年   6篇
  1973年   3篇
  1971年   8篇
  1969年   3篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
1.
2.
AIM: We evaluated differences between men and women with lower urinary tract symptoms (LUTS) combined with nocturia. METHODS: A total of 71 age-matched female-male pairs (median 58, range 20-81 years) who had moderate to severe LUTS and nocturia of more than once per night were enrolled in this study. RESULTS: In the younger group (<50 years), the International Prostate Symptom Score (I-PSS) results of the sexes were not significantly different. However, although total I-PSS results in the elderly group (> or =50 years) were not significantly different, quality of life index scores for women were higher (P = 0.002). On frequency-volume (FV) charts, mean total daytime voided volume (DVV) was significantly higher in younger men than in younger women (P = 0.017), but the mean nocturnal polyuria index (NPi) for women was higher than that for men (P = 0.047). However, maximum DVV (P = 0.009), mean DVV (P < 0.0001), total DVV (P < 0.0001), and mean nocturnal urine volume (P = 0.009) were significantly higher in elderly men than in elderly women. However, numbers of daytime voids were not different. CONCLUSION: Elderly women with LUTS have lower functional bladder capacities than elderly men, as suggested by their smaller mean voided volumes. However, no significant differences were observed between numbers of daytime voids, which was probably due to the smaller total daytime voided volumes of elderly women. In addition, although NPi for younger women and nocturnal urine volume for elderly men was higher, no other differences were observed in terms of other night-time parameters.  相似文献   
3.
OBJECTIVES: Vesicoureteral reflux (VUR) is the most common congenital urinary tract anomaly. This disease can pose a major threat to the kidneys as twenty percent of patients with endstage renal disease are reported to have VUR. Although genetic studies for uroplakin III (UPIII) have been reported recently, no study has focused on UPIII gene expression in VUR patients. We describe here the up-regulation of UPIII mRNA in exfoliated urinary cells from primary VUR patients. METHODS: A real-time RT-PCR for UPIII mRNA was performed on exfoliated urothelial cells from 18 primary VUR and 38 control samples. UPIII mRNA copies were calculated for each sample. The statistical differences were assessed by the Mann-Whitney U test. Receiver operator characteristic curves were constructed for analysis of the diagnostic values. RESULTS: UPIII mRNA was found to be up-regulated to a greater extent in VUR than in control exfoliated urinary cells (mean +/- SE: 497.0 +/- 178.5 copies vs. 69.0 +/- 10.0 copies, respectively, P < 0.001). In evaluating the measurement of urinary UPIII mRNA as a screening test for VUR, the sensitivity was 77.8% and the specificity was 76.3% by the best diagnostic cutoff point. CONCLUSIONS: This is the first report demonstrating up-regulation of UPIII in mRNA levels in VUR patients. We submit that the quantitative measurement of urinary UPIII mRNA has a potential of developing into the first non-invasive screening test for VUR.  相似文献   
4.
5.
The relationship between primary tumor proliferative activity and clinical and pathologic characteristics was analyzed in relation to menopausal status in 32 patients with malignant or benign breast disease. The thymidine labeling index (TLI) showed significantly higher median values in the cancer patients (3.48 per cent) than in the patients with benign diseases (1.02 per cent). TLI was not significantly affected by delayed incubation at room temperature for about 1 hour. In the breast cancer patients, TLI did not significantly correlate to tumor size, the presence of axillary lymph node metastasis or pathologic nuclear grading. The only significant difference was limited to the breast cancer patients without axillary lymph node metastasis in relation to menopausal status; the TLI in the premenopausal patients (5.10 per cent) was significantly higher (p<0.05) than that in the postmenopausal patients (2.28 per cent). These data thus suggest that among premenopausal patients without axillary lymph node metastasis, those with a high TLI could be potential candidates for adjuvant chemotherapy.  相似文献   
6.
Perforation of the large bowel during colonoscopy in Singapore   总被引:1,自引:0,他引:1  
The management of seven patients with colonoscopy-related perforations is described. This study demonstrates the need for an early laparotomy. A high index of suspicion is required to reach an early diagnosis. Patients with no preexisting medical problems who underwent early surgery recovered with little morbidity. In elderly patients (greater than 75 years), colonoscopic perforation can be fatal. Endoscopy should be performed with special care in such patients.  相似文献   
7.
8.
Autoimmune cholangitis is a clinical constellation of chronic cholestasis, histological changes of chronic nonsuppurative cholangitis and the presence of autoantibodies other than antimitochondrial antibody (AMA). It is uncertain whether this entity is definitely different from AMA positive primary biliary cirrhosis (PBC), though it shows some differences. We report a case of autoimmune cholangitis in a 59-year-old woman, who had been previously diagnosed as AMA-positive PBC associated with rheumatoid arthritis, has been converted to an AMA-negative and anticentromere antibody-positive PBC during follow-up. The response to ursodeoxycholic acid treatment is poor except within the first few months, but prednisolone was dropping the biochemical laboratory data.  相似文献   
9.
We report a case of ruptured mycotic aneurysm involving innominate artery requiring an urgent surgical treatment. A 62-yr-old woman presented with fever and dyspnea. Previously, she was diagnosed with colon cancer and received right hemicolectomy and one cycle of adjuvant chemotherapy. On echocardiogram, pericardial effusion was noted and emergency pericardiocentesis was performed. CT scan revealed aortic aneurysm involving ascending aorta and innominate artery, and thrombi surrounding those structures. Patch repair of the defect in the ascending aorta and ringed Goretex graft to bypass the innominate and ascending aorta were performed. We believe that this is the first case of ruptured mycotic aneurysm involving innominate artery.  相似文献   
10.
Banna virus (BAV, genus Seadornavirus, family Reoviridae) is an arbovirus suspected to be responsible for encephalitis in humans. Two genotypes of this virus are distinguishable: A (Chinese isolate, BAV-Ch) and B (Indonesian isolate, BAV-In6969) which exhibit only 41% amino-acid identity in the sequence of their VP9.The VP7 to VP12 of BAV-Ch and VP9 of BAV-In6969 were expressed in bacteria using pGEX-4T-2 vector. VP9 was chosen to establish an ELISA for BAV, based mainly on two observations: (i). VP9 is a major protein in virus-infected cells and is a capsid protein (ii). among all the proteins expressed, VP9 was obtained in high amount and showed the highest immuno-reactivity to anti-BAV ascitic fluid.The VP9s ELISA was evaluated in three populations: French blood donors and two populations (blood donors and patients with a neurological syndrome) from Malaysia, representing the region where the virus was isolated in the past.The specificity of this ELISA was >98%. In mice injected with live BAV, the assay detected IgG-antibody to BAV infection 21 days post-injection, which was confirmed by Western blot using BAV-infected cells.The VP9 ELISA permits to determine the sero-status of a population without special safety precautions and without any requirements to propagate the BAV. This test should be a useful tool for epidemiological survey of BAV.  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