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   2240篇
  免费   114篇
  国内免费   8篇
耳鼻咽喉   23篇
儿科学   202篇
妇产科学   35篇
基础医学   253篇
口腔科学   60篇
临床医学   153篇
内科学   414篇
皮肤病学   99篇
神经病学   134篇
特种医学   71篇
外科学   246篇
综合类   34篇
预防医学   100篇
眼科学   76篇
药学   307篇
中国医学   36篇
肿瘤学   119篇
  2023年   8篇
  2022年   17篇
  2021年   64篇
  2020年   35篇
  2019年   49篇
  2018年   76篇
  2017年   46篇
  2016年   46篇
  2015年   59篇
  2014年   85篇
  2013年   100篇
  2012年   173篇
  2011年   166篇
  2010年   89篇
  2009年   85篇
  2008年   147篇
  2007年   136篇
  2006年   140篇
  2005年   114篇
  2004年   100篇
  2003年   96篇
  2002年   86篇
  2001年   43篇
  2000年   36篇
  1999年   32篇
  1998年   25篇
  1997年   14篇
  1996年   13篇
  1995年   7篇
  1994年   15篇
  1993年   8篇
  1992年   34篇
  1991年   31篇
  1990年   22篇
  1989年   15篇
  1988年   14篇
  1987年   9篇
  1986年   8篇
  1985年   13篇
  1984年   6篇
  1982年   10篇
  1978年   9篇
  1974年   5篇
  1973年   4篇
  1972年   5篇
  1971年   5篇
  1970年   7篇
  1969年   7篇
  1968年   6篇
  1966年   5篇
排序方式: 共有2362条查询结果,搜索用时 15 毫秒
1.
2.
3.
Previous studies have demonstrated that granulocyte-macrophage colony-stimulating factor (GM-CSF) both increases and decreases levels of 3'-azido-3'-deoxythymidine (AZT) nucleotides in certain human myeloid cells. The present studies have examined the effects of GM-CSF on AZT metabolism in U-937 cells. The results demonstrate that GM-CSF stimulated AZT nucleotide formation in these cells. This stimulation was detectable during concurrent exposure to GM-CSF and AZT or as a result of pretreatment with GM-CSF. The GM-CSF-induced enhancement in AZT nucleotide formation was associated with a 4-fold increase in AZT uptake. The finding that uptake of AZT into U-937 cells was only partially sensitive to 6-[(4-nitrobenzyl)thio]-9-beta-D-ribofuranosylpurine (NBMPR) suggested a process primarily involving nonfacilitated diffusion. The results also demonstrate that treatment of U-937 cells with GM-CSF was associated with nearly a 2-fold increase in thymidine kinase activity. Moreover, the findings indicate that retention of AZT-MP and AZP-TP was prolonged significantly (P less than 0.05 and P less than 0.01 respectively) in association with GM-CSF treatment. Taken together, these results suggest that GM-CSF enhances the formation of AZT nucleotides by increasing AZT uptake and phosphorylation, as well as increasing retention of phosphorylated derivatives.  相似文献   
4.
We report the case of a 25-year-old male patient who presented with complaints of redness, photophobia, and decreased vision in the right eye of a week's duration. Slit-lamp biomicroscopic examination revealed a cream-colored, irregular elevated inferior iris mass, extending on to the anterior lens surface. Differential diagnoses of a fungal granuloma, a medulloepithelioma, and an amelanotic melanoma were considered. An excisional biopsy of the mass was performed through a superior clear corneal incision. Polymerase chain reaction analysis of the aqueous humor showed a positive pan fungal genome. Histopathology of the biopsied mass showed a giant cell granuloma with surrounding numerous branching, septate hyphae. Culture growth revealed Aspergillus fumigatus We report this case because of the rarity of Aspergillus iris granuloma as a primary presentation of endogenous Aspergillosis and review the relevant literature. Absence of a significant systemic history compounded the diagnostic dilemma in our patient. Definitive differentiation of this rare entity from a foreign body, amelanotic melanoma, and other inflammatory conditions such as sarcoidosis and tuberculosis, may be possible only on microbiological and histo-pathological evaluation.  相似文献   
5.
A decided attitude of expectation among many patients has given a new perspective to regenerative and plastic periodonta surgery. With authors emphasizing on the importance of gingival thickness, attempts are being made to obtain necessary information atraumatically and rapidly. Hence in the present study an attempt has been made to compare the two methods of assessing gingival thickness i.e transgingival probing and ultrasonographic method and also assess the gingival thickness in relation to central incisor lateral incisor and canine in Indian population. The gingival thickness was assessed in patients with healthy gingiva by both the methods. It was observed that transgingival probing method significantly over estimated the thickness of gingiva than the ultrasonographic method and the thickness of gingiva varies with morphology of the crown. It was concluded that compared to transgingival probing ultrasonographic method assesses gingiva thickness more accurately, rapidly and atraumatically.  相似文献   
6.
We report our experience of pediatric liver transplantation with partial grafts from non-heart beating donors (NHBD). Controlled donors less than 40 years of age with a warm ischemia time (WI) of less than 30 min were considered for pediatric recipients. Death was declared 5 min after asystole. A super-rapid recovery technique with aortic and portal perfusion was utilized. Mean donor age was 29 years and WI 14.6 min (range 11–18). Seven children, mean age 4.9 years (0.7–11), median weight 20 kg (8.4–53) received NHBD segmental liver grafts. Diagnoses included seronegative hepatitis, neonatal sclerosing cholangitis, familial intrahepatic cholestasis, hepatoblastoma, primary hyperoxaluria and factor VII deficiency (n = 2).The grafts included four reduced and one split left lateral segments, one left lobe and one right auxiliary graft. Mean cold ischemia was 7.3 h (6.2–8.8). Complications included one pleural effusion and one biliary collection drained percutaneously. At 20 months (10–36) follow-up all children are alive and well with functioning grafts.
Donation after cardiac death is a significant source of liver grafts for adults and children with careful donor selection and short cold ischemic times.  相似文献   
7.
BACKGROUND: The treatment of hepatitis C virus (HCV)-related cirrhosis is difficult due to high frequency of adverse effects. We retrospectively reviewed the case records of patients with HCV cirrhosis to evaluate the efficacy and tolerability of pegylated (peg) interferon and ribavirin treatment in these patients. METHODS: Medical records of 28 patients with HCV-related compensated cirrhosis were reviewed. The treatment protocol was a combination therapy of peg interferon alfa-2b (1 microg/Kg/week) plus oral ribavirin (10-12 mg/Kg/day). Primary endpoint was sustained virological response, with additional endpoints of drug tolerance, clinical or biochemical worsening and death. RESULTS: End-of-treatment virlogic response was seen in 24 of 28 patients (85%) and sustained virologic response in 15 of 28 (53%) patients. Biochemical end-of-treatment response and sustained response were seen in 20 and 16 patients (71% and 57%), respectively. Treatment had to be stopped in 3 patients due to decompensation of liver status in two and drug intolerance in one, while dose modification was required in two patients. CONCLUSIONS: Combination therapy with peg interferon plus ribavirin seems effective in patients with liver cirrhosis. High relapse rate, poor biochemical recovery and possibility of decompensation are issues that need to be kept in mind.  相似文献   
8.
9.
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