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   8434篇
  免费   507篇
  国内免费   113篇
耳鼻咽喉   127篇
儿科学   151篇
妇产科学   81篇
基础医学   1408篇
口腔科学   141篇
临床医学   697篇
内科学   1778篇
皮肤病学   481篇
神经病学   626篇
特种医学   518篇
外科学   1026篇
综合类   19篇
现状与发展   1篇
一般理论   1篇
预防医学   311篇
眼科学   192篇
药学   833篇
中国医学   143篇
肿瘤学   520篇
  2024年   7篇
  2023年   74篇
  2022年   241篇
  2021年   340篇
  2020年   179篇
  2019年   231篇
  2018年   283篇
  2017年   232篇
  2016年   322篇
  2015年   401篇
  2014年   514篇
  2013年   485篇
  2012年   786篇
  2011年   773篇
  2010年   403篇
  2009年   370篇
  2008年   499篇
  2007年   428篇
  2006年   346篇
  2005年   380篇
  2004年   266篇
  2003年   224篇
  2002年   225篇
  2001年   175篇
  2000年   184篇
  1999年   130篇
  1998年   48篇
  1997年   27篇
  1996年   35篇
  1995年   15篇
  1994年   32篇
  1993年   16篇
  1992年   41篇
  1991年   44篇
  1990年   37篇
  1989年   49篇
  1988年   28篇
  1987年   30篇
  1986年   25篇
  1985年   22篇
  1984年   10篇
  1983年   6篇
  1981年   9篇
  1980年   14篇
  1979年   15篇
  1978年   7篇
  1977年   9篇
  1971年   4篇
  1970年   4篇
  1967年   4篇
排序方式: 共有9054条查询结果,搜索用时 15 毫秒
141.
Summary. Clevudine shows high rates of virologic and biochemical responses in patients with chronic hepatitis B. However, the efficacy and safety of clevudine in patients with cirrhosis are unknown. The aims of this study were to evaluate the safety and to assess the virologic and the biochemical responses to clevudine in patients with cirrhosis with chronic hepatitis B virus (HBV) infection. We reviewed data from treatment‐naïve patients with chronic hepatitis B with and without cirrhosis who started clevudine between April 2007 and March 2008 (n = 52, hepatitis B without cirrhosis n = 21 and chronic hepatitis B with cirrhosis n = 31) at Korea University Ansan/Guro Hospital. All of the patients were treated for more than 48 weeks. The mean age was older in the patients with cirrhosis. Baseline HBV DNA levels were 6.9 and 7.78 log copies/mL (P = 0.042), and alanine aminotransferase (ALT) levels were 104.9 and 147.4 IU/L (P = 0.204), for those with and without cirrhosis, respectively. Virologic response (HBV DNA <1000 copies/mL) (87.1%vs 71.4%, P = 0.24) and biochemical response (83.9%vs 80.9%, P = 0.99) at week 48 were not significantly different between the two groups. Early virologic response at week 12 was even higher in the patients with cirrhosis (61.3%vs 28.6%, P = 0.026). Neither ALT flare nor newly onset hepatic decompensation was found in the patients with cirrhosis, whereas ALT flare was transiently observed in 14.3% of the chronic hepatitis group. In conclusion, although clevudine may produce a transient elevation of ALT during the early treatment period, such findings were not observed in patients with cirrhosis and the virologic and biochemical responses of the groups were comparable.  相似文献   
142.
AIM: To investigate the anti-diabetogenic mechanism of Nardostachys jatamansi extract (NJE). METHODS: Mice were injected with streptozotocin viaa tail vein to induce diabetes. Rat insulinoma RINm5F cells and isolated rat islets were treated with interleukin1β and interferon-γ to induce cytotoxicity. RESULTS: Treatment of mice with streptozotocin resulted in hyperglycemia and hypoinsulinemia, which was conf irmed by immunohistochemical staining of the islets. The diabetogenic effects of streptozotocin were c...  相似文献   
143.
144.
The shortage of donor organs occasionally mandates the use of hepatic allografts from anti-HBc (+) donors. HBIG and/or lamivudine are recommended for the prevention of de novo HBV infection in naive patients, but there are attendant problems, such as mutant strain emergence and high cost. Active immunization presents a better alternative than the use of HBIG or lamivudine, if it can be proven to be effective. Accordingly, we investigated the outcome of HBV vaccination in pediatric hepatic transplant recipients. Between July 1999 and October 2001, 19 pediatric recipients were administered HBV vaccinations after liver transplantation at Seoul National University Hospital. Nine patients received a graft from anti-HBc (+) donors and 10 from anti-HBc (-) donors. When steroid was withdrawn, recombinant HBV vaccine was administered. The median follow-up period after vaccination was 10.0 +/- 5.2 months. Seventeen of the 19 patients showed a positive response to vaccination. In 9 patients who received grafts from anti-HBc (+) donors, 2 patients showed no response, 4 patients low response (peak HBsAb titer <1,000 IU/L), and 3 patients high response (peak HBsAb titer >/=1,000 IU/L). De novo HBV infection developed in 1 of 2 patients who showed no response to vaccination. In 10 patients who received grafts from anti-HBc (-) donors, 5 showed a low response and 5 a high response. In conclusion, HBV vaccination in pediatric patients after liver transplantation appeared to exhibit some effectiveness at protecting young children that received a graft from anti-HBc (+) donors from de novo HBV infection.  相似文献   
145.
Objectives: Cytomegalovirus (CMV) disease is more common in immunocompromised patients but may occur in people with normal immune function. In addition, CMV enterocolitis can aggravate inflammatory bowel diseases (IBD), but there was little knowledge of differences in clinical and endoscopic features of CMV enterocolitis between patients with IBD and without IBD. The aim of this study was to determine the difference in clinical implication in CMV enterocolitis between the IBD patients and non-IBD patients.

Methods: This was a retrospective study of 82 patients with CMV enterocolitis based on the pathologic findings at two tertiary referral hospitals from 2003 to 2013. Clinical and endoscopic characteristics and clinical course were analyzed according to the presence of IBD.

Results: Of the 82 patients, 25 (30.5%) had IBD and 57 (69.5%) did not have IBD. Hematochezia was more common in IBD patients (84.0% vs. 35.1%; p = .001), but fever and positive CMV antigenemia were more common in non-IBD patients (50.9% vs. 12.0%; p = .001; 54.4% vs. 28.0; p = .027). Endoscopic findings showed more ulcer with inflammation in IBD patients (68.0% vs. 35.2%; p = .005). Sixty-four patients were treated with antiviral agents and 12 patients who did not receive antiviral agents recovered spontaneously. All naturally healed patients were in normal immune status.

Conclusions: Hematochezia is more common in IBD patients and fever/CMV antigenemia is more common in patients without IBD. In patients without IBD, the natural resolution of CMV enterocolitis is expected at least in normal immune function.  相似文献   

146.
147.
Verapamil is widely used for the termination of paroxysmal supraventricular tachycardia (PSVT) with little proarrhythmic effect. We describe two cases of PSVT that changed to non-sustained polymorphic ventricular tachycardia after administration of verapamil. Electrophysiological study revealed atrioventricular nodal reentrant tachycardia in the first case, and atrioventricular reentrant tachycardia due to a concealed left lateral accessory pathway in the second case. Catecholamine-induced automaticity was one of the possible mechanisms of VT in the first case, but the mechanism is unknown in the second case.  相似文献   
148.
Cruciate ligament integrity in osteoarthritis of the knee   总被引:14,自引:0,他引:14  
OBJECTIVE: To evaluate, using magnetic resonance imaging (MRI), the prevalence of anterior cruciate ligament (ACL) and posterior cruciate ligament (PCL) rupture in knees with symptomatic osteoarthritis (OA) compared with those without OA, and the relationship to pain and recalled injury. METHODS: MRI and plain radiography of the knee were performed in a group of 360 subjects with painful knee OA (cases; 66.7% male, mean age 67.1 years) and 73 without knee pain (controls; 57.5% male, mean age 66.1 years). MRIs were read for the presence or absence of complete or partial ACL or PCL tear. Subjects with knee pain were asked to quantify severity of pain on a visual analog scale and to report whether they could recall a significant knee injury (requiring use of a cane or crutches). We compared the prevalence of ACL and PCL rupture in those with and those without knee pain and also evaluated whether, in cases, there was any association with recalled knee injury. RESULTS: The proportion of cases who had complete ACL rupture was 22.8%, compared with 2.7% of controls (P = 0.0004). PCL rupture was rare both in cases (0.6%) and in controls (0%). Cases with ACL rupture had more severe radiologic OA (P < 0.0001) and were more likely to have medial joint space narrowing (P < 0.0001) than cases with intact ACLs, but did not have higher pain scores. Among cases, only 47.9% of those with complete ACL tears reported a previous knee injury, compared with 25.9% of those without complete ACL tears (P = 0.003). CONCLUSION: ACL rupture is more common among those with symptomatic knee OA compared with those without knee OA. Fewer than half of subjects with ACL rupture recall a knee injury, suggesting that this risk factor for knee OA is underrecognized.  相似文献   
149.
150.
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