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   14805篇
  免费   925篇
  国内免费   179篇
耳鼻咽喉   2篇
儿科学   513篇
妇产科学   568篇
基础医学   690篇
口腔科学   13篇
临床医学   1715篇
内科学   1115篇
皮肤病学   55篇
神经病学   231篇
特种医学   254篇
外国民族医学   2篇
外科学   6082篇
综合类   1820篇
预防医学   755篇
眼科学   14篇
药学   1204篇
  19篇
中国医学   442篇
肿瘤学   415篇
  2024年   157篇
  2023年   237篇
  2022年   355篇
  2021年   574篇
  2020年   656篇
  2019年   570篇
  2018年   590篇
  2017年   610篇
  2016年   545篇
  2015年   530篇
  2014年   980篇
  2013年   1068篇
  2012年   692篇
  2011年   913篇
  2010年   848篇
  2009年   747篇
  2008年   705篇
  2007年   667篇
  2006年   656篇
  2005年   525篇
  2004年   486篇
  2003年   392篇
  2002年   307篇
  2001年   250篇
  2000年   181篇
  1999年   191篇
  1998年   141篇
  1997年   117篇
  1996年   118篇
  1995年   92篇
  1994年   82篇
  1993年   85篇
  1992年   72篇
  1991年   68篇
  1990年   75篇
  1989年   62篇
  1988年   62篇
  1987年   58篇
  1986年   52篇
  1985年   66篇
  1984年   52篇
  1983年   41篇
  1982年   46篇
  1981年   26篇
  1980年   25篇
  1979年   28篇
  1978年   29篇
  1977年   20篇
  1976年   16篇
  1975年   16篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
991.
Two main types of erythrocytes can be found in the urine, i.e.dysmorphic erythrocytes, which are a marker of glomerular bleeding,and isomorphic erythrocytes, which are a marker of urologicaldisorders  相似文献   
992.
AIM: The aim of this study was to evaluate the efficacy of solvent-dehydrated cadaveric dermis in pubovaginal sling surgery for the first time in the literature. METHODS: Twenty-five women with stress urinary incontinence underwent pubovaginal sling surgery using 2 x 12 cm allograft dermis. Preoperatively, all patients were evaluated by a detailed urogynecologic evaluation, voiding diary, pelvic examination and urodynamic investigation. Outcome was assessed by the Urogenital Distress Inventory short form and standardized follow-up questionnaires. RESULTS: Twenty (80%) patients were cured of stress incontinence symptoms. Seventeen wore no pad and three reported occasional stress urinary incontinence and used no or one pad at a mean follow up of 12 months. Five (20%) patients in our series experienced the same amount of leakage as before the surgery. Seventy-six percent of the patients indicated that urinary incontinence was no longer negatively affecting their daily life and were satisfied with the procedure. CONCLUSIONS: Questionnaire-based assessment of outcome suggests that solvent-dehydrated cadaveric dermis is effective in the treatment of stress urinary incontinence. However, larger and comparative prospective studies with long-term results and randomized comparison of tissue preparation techniques are warranted.  相似文献   
993.
Microalbuminuria in non-insulin-dependent diabetes (NIDDM) is a strong predictor of increased mortality. The major causes of death are cardiovascular, whereas end-stage renal failure is of low frequency. To define kidney function and the presence of some assumed cardiovascular risk factors, we compared a group of 19 microalbuminuric NIDDM patients (M), of mean age (+/- SD) 65 +/- 4 years, and known duration of diabetes 8 +/- 7 years, with 19 randomly selected matched normoalbuminuric patients (N). Seven microalbuminuric patients (P) were also studied. Glomerular filtration rate (GFR) did not differ between N and M, whereas kidney volume was increased in M (260.3 +/- 54.1 ml 1.73 m-2) compared to N (220.4 +/- 44.8 ml 1.73 m-2; P = 0.018). The frequency of cardiac disease increased with increasing albuminuria. Glycaemic control did not differ between the groups, but fasting plasma C-peptide levels increased from 2.8 +/- 1.1 micrograms l-1 in N, to 3.7 +/- 1.7 micrograms l-1 in M (P = 0.08), and to 4.2 +/- 1.9 micrograms l-1 (P = 0.03) in P. The lipoprotein profile showed no significant differences, although the LDLcholesterol/HDLcholesterol (LDL-C/HDL-C) ratio tended to rise. A significant correlation was found between C-peptide and LDL-C/HDL-C (r = 0.5; P less than 10(-3]. In conclusion, GFR was not increased, and did not differ between N and M, whereas kidney volume was enhanced in M. Several assumed cardiovascular risk factors showed values of M intermediate between those of N and P.  相似文献   
994.
Summary Chemotherapeutic agents were evaluated for effect on the development of urinary bladder tumors induced by N-butyl-N-(4-hydroxybutyl) nitrosamine (BBN) in male Wistar strain rats. Seven hundred and two rats were given 0.05% BBN in drinking water for 8 weeks. After BBN treatment, the animals were divided into 26 groups to follow regimens of single chemotherapy. All drugs were administered intraperitoneally except in one group that was treated orally. In our experimental series, 5-fluorouracil (5-FU), N-(2-tetrahydrofuryl)-5-fluorouracil (FT-207), carbazilquinone (CQ), vincristine (VCR) and cis-diamminedichloroplatinum (CDDP) were effective in inhibiting the incidence of bladder tumor, however, adriamycin (ADM), mitomycin C (MMC), neocarsinostatin (NCS), cyclophosphamide (CPM) and bleomycin (BLM) were not effective.  相似文献   
995.
OBJECTIVE: To evaluate the influences the change of the measurement method of pyuria from conventional centrifuged sediment to microchamber uncentrifuged urine for the results of evaluation of antimicrobial agents in clinical study against complicated urinary tract infections. From the viewpoint of international harmonization of judgement criteria, the recent method for counting white blood cells (WBC) in urine has changed from using uncentrifuged urine to using a microchamber in all countries. METHODS: Targeted diseases were non-catheterized complicated urinary tract infection, and cefcapene pivoxil hydrochloride or levofloxacin were used as antimicrobial drug. Pyuria was examined using the counting chamber method, a quantitative method using uncentrifuged urine with a microchamber, and the sedimentation method. RESULTS: Overall clinical efficacy in early evaluation by the two methods in measuring pyuria was evaluated as different in eight patients (7.3%). It was rated excellent in 63 (52.9%), moderate in 32 patients (26.9%) and poor in 24 (20.2%) with an efficacy rate of 79.8% using the counting chamber method, and excellent in 68 (57.1%), moderate in 27 (22.7%) and poor in 24 (20.2%) with an efficacy rate of 79.8% using the conventional sedimentation method CONCLUSION: No significant difference was seen between the two methods of WBC count in urine.  相似文献   
996.
BACKGROUND: Statins improve cardiovascular outcome, but less is known on the renal outcome. We, therefore, studied the relationship between the use of statins and urinary albumin excretion (UAE) and glomerular filtration rate (GFR) in two settings: a randomized controlled trial (RCT) and an observational cohort study, in which patients were included to study the impact of an elevated UAE on renal and cardiovascular prognosis. METHODS: We used data from the Prevention of REnal and Vascular ENd-stage Disease Intervention trial (PREVEND-IT) and the PREVEND cohort study. The PREVEND-IT subjects (788 with a UAE 15-300 mg/day) received pravastatin 40 mg/day vs placebo and/or fosinopril 20 mg/day vs placebo in a 2x2 factorial-RCT design. Of the 3440 cohort subjects, 469 used statins during the 4-year follow-up period. Multivariate-regression adjusted for confounding factors and the propensity score was used to estimate the relation between statin use and UAE and GFR. RESULTS: In the RCT, pravastatin did not change UAE or GFR, neither in fosinopril yes/no subgroups. In the observational cohort, statin use was associated with a rise in UAE (+12.1%), compared with statin non-use (+3.6%, P<0.001). This rise was most pronounced in those on statins prior to the first screening [+24.8% (95% CI: 11.9-39.2)], those using statins>3 years [+18.5% (7.3-30.8)] and those with >1 or >2 defined daily doses (+15.7 and +17.3%, respectively). These differences remained significant after adjustment for relevant variables and propensity score. The rise in UAE could not be attributed to a higher dose or a specific statin. GFR fell in 4 years in both statin users and non-users (4.6+/-13.5 and 2.4+/-11.2, respectively). The fall in GFR between groups was not different after adjustment (P=0.11). CONCLUSIONS: We conclude from the RCT data that statins do not lower UAE in subjects selected because of an elevated UAE instead of hyperlipidaemia. In the observational cohort study, the use of statins similarly was not associated with a fall in UAE; UAE instead increased. Statin treatment was not associated with a significant change in GFR in these subjects with only modestly impaired GFR.  相似文献   
997.
AIM: The clinical significance of the urinary white blood cell (U-WBC) count and serum C-reactive protein (CRP) level was evaluated in an effort to improve the efficiency of prostate biopsies. METHODS: We enrolled 228 consecutive patients with serum prostate-specific antigen (PSA) ranging from 3.0 to 20.0 ng/mL, normal digital rectal examination findings, and who underwent prostate biopsies between January 2001 and August 2004. Of these, 157 patients had histologically confirmed benign prostatic disease and the remaining 71 patients had prostate cancer. Patients with a pretreatment U-WBC count < or =3 or >3/high power field were defined as non-pyuria and pyuria, respectively. The patients were also separated into two groups based on the serum CRP level prior to biopsy. Several clinical factors were compared among these subgroups. RESULTS: Inflammation was histologically detected at rates of 58.1% and 34.1% in the pyuria and non-pyuria groups, respectively (P = 0.0014). The rates of cancer detection were significantly lower in the pyuria, than in the non-pyuria group (P = 0.0384). The cancer detection rates did not significantly differ according to serum CRP levels prior to biopsy. CONCLUSION: The U-WBC count appears to be a reliable indicator of minute prostatic inflammation. The serum PSA level was elevated in patients with asymptomatic prostatitis. Counting U-WBC is a simple, convenient and non-invasive method that should be valuable part of routine urological examinations.  相似文献   
998.
999.
1000.
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