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   4081篇
  免费   187篇
  国内免费   42篇
耳鼻咽喉   154篇
儿科学   241篇
妇产科学   209篇
基础医学   340篇
口腔科学   109篇
临床医学   324篇
内科学   1011篇
皮肤病学   138篇
神经病学   269篇
特种医学   150篇
外科学   662篇
综合类   70篇
预防医学   90篇
眼科学   162篇
药学   137篇
中国医学   8篇
肿瘤学   236篇
  2024年   3篇
  2023年   29篇
  2022年   40篇
  2021年   95篇
  2020年   73篇
  2019年   82篇
  2018年   117篇
  2017年   86篇
  2016年   148篇
  2015年   177篇
  2014年   188篇
  2013年   231篇
  2012年   328篇
  2011年   350篇
  2010年   175篇
  2009年   155篇
  2008年   346篇
  2007年   361篇
  2006年   331篇
  2005年   277篇
  2004年   249篇
  2003年   184篇
  2002年   154篇
  2001年   26篇
  2000年   18篇
  1999年   16篇
  1998年   13篇
  1997年   7篇
  1996年   11篇
  1995年   8篇
  1994年   4篇
  1993年   2篇
  1992年   6篇
  1991年   3篇
  1990年   2篇
  1988年   1篇
  1986年   2篇
  1985年   1篇
  1984年   5篇
  1982年   2篇
  1981年   1篇
  1980年   2篇
  1971年   1篇
排序方式: 共有4310条查询结果,搜索用时 62 毫秒
981.
Brucellosis is considered the most widespread zoonosis in the world. In endemic regions of brucellosis, childhood brucellosis includes up to one‐third of all cases of human brucellosis. Brucellosis constitutes a public health problem in Turkey. A boy aged 12 yr who had PFIC2 had undergone deceased‐donor liver transplantation in 2008 at the age of seven. The boy presented with fatigue, fever, and pain in the right leg and hip and was admitted to the hospital. Brucella melitensis grew in the blood culture, and the SAT was positive at a titer of 1:640. The patient was treated with oral doxycycline and rifampicin for eight wk. After treatment, the patient recovered and his blood cultures became negative. The patient's mother also had a high Brucella agglutination titer of 1:320 positive and was treated in the internal medicine department with spiramycin and doxycycline. Brucella infection should be suspected in liver transplant recipients with fever of unknown origin, especially in recipients who live in an endemic area.  相似文献   
982.
Homocysteine concentrations in subclinical hypothyroidism   总被引:2,自引:0,他引:2  
Hyperhomocysteinemia is considered to be an independent risk factor for atherosclerotic heart disease, including coronary artery disease (CAD). It is already known that overt hypothyroidism gives rise to a slight hyperhomocysteinemia. However, the effects of subclinical hypothyroidism on the levels of homocysteine are not known. In this study, we have evaluated homocysteine levels and the effect of L-thyroxine treatment in patients with subclinical hypothyroidism. For the purpose of the study, we selected 33 women patients with the diagnosis of subclinical hypothyroidism but without clinical CAD. After a euthyroidism development period of almost four months, a further study was done on patients who had been treated with thyroid hormone. The patient group was compared with 25 healthy control female subjects who were of similar age. In the patient group, homocysteine levels prior to treatment were significantly higher than in the control group (P < 0.001). After L-thyroxine treatment, homocysteine levels were reduced significantly. In summary, we found that homocysteine levels were in the normal range in subclinical hypothyroidism. However, when compared with the healthy control group, the difference between them was significant. On the other hand, therapy to produce euthyroidism caused a significant reduction in homocysteine levels.  相似文献   
983.
984.
Mean platelet volume (MPV), a determinant of platelet function, is a newly emerging risk factor for atherothrombosis. The risk profile of white coat hypertension has not yet been completely clear. The present study was designed to evaluate MPV in white coat hypertensive subjects compared with essential hypertensive patients and normotensive subjects. We selected 36 essential hypertensive patients, 36 white coat hypertensive subjects and 36 normotensive control subjects matched for age, gender, and body mass index. MPV was very significantly higher in essential hypertensives and white coat hypertensives than in normotensives (P < 0.00); it was also higher in essential hypertensives than in white coat hypertensives (P < 0.05). Platelet counts were not different among the study groups (P > 0.05). MPV was positively correlated with ambulatory diastolic blood pressure in essential hypertension and white coat hypertension groups (P < 0.05). In conclusion, our data suggests one possible mechanism by which white coat hypertensive subjects may be at increased cardiovascular risk.  相似文献   
985.
BACKGROUND/AIMS: Controlled studies in humans have shown the role of antibodies to tumor necrosis factor-alpha in the treatment of both fistulizing and inflammatory Crohn's disease. The aim of this study is to report the results of a multicenter clinical trial to evaluate efficacy of infliximab in Crohn's disease patients who are refractory to conservative drugs or fistulizing Crohn's disease. METHODOLOGY: This trial was carried out at 5 university and community hospitals, in Turkey. A total of 25 patients with Crohn's disease that were unresponsive to conventional medical therapy, participated; 17 of the 25 were in the fistulizing disease group and 8 were in the inflammatory disease group. Clinical response was classified according to fistula drainage, diarrhea as positive response or no response. RESULTS: Overall response rate was 92% (23/25), regardless of the disease group, after first infusion of infliximab. Sixteen out of 17 patients in the fistulizing disease group had a positive response. Fourteen of the 16 positive responders later relapsed. Median duration of response was 8 weeks (range, 2-35 wk). Active inflammatory disease patients had a positive response rate of 75% (6/8) and two of the patients were nonresponders. A further two patients relapsed at week 14. Two patients in both arms of the study were still in remission at the end of the study. Major adverse events were: pneumonia in one patient, skin infections in two patients, pulmonary thromboembolism and death in one patient. CONCLUSIONS: Infliximab treatment seems to be more effective in Crohn's disease patients especially in those with fistulizing disease than those with non-fistulizing, inflammatory disease. It is evident that maintenance of remission might be achieved with ongoing maintenance therapy. We suggest maintenance of infliximab therapy.  相似文献   
986.
BACKGROUND: Quadruple therapy with a proton pump inhibitor, bismuth, metronidazole and tetracycline is recommended as the optimal second-line therapy of Helicobacter pylori infection in the Maastricht Consensus Report. The aim of the present paper was to evaluate the efficacy of ranitidine bismuth citrate (RBC)-based regimens as second-line therapies after failure of the standard Maastricht triple therapy. MATERIALS AND METHODS: One hundred and sixteen H. pylori-positive patients were given omeprazole 20 mg b.d., clarithromycin 500 mg b.d., and amoxicillin 1 g b.d for 10 days. Patients remaining H. pylori-positive (n = 29) were combined with 27 patients enrolled after an initial eradication failure from proton-pump inhibitor (PPI), amoxicillin and clarithromycin therapy for at least 7 days and were randomly given one of the following second-line 10-day treatments: RBC 400 mg b.d., amoxicillin 1 g b.d and clarithromycin 500 mg b.d. (RAC group, n = 28) and RBC 400 mg b.d., metronidazole 500 mg b.d and tetracycline 500 mg b.d. (RMT group, n = 28). Eradication was assessed by either histology and rapid urease test or (13)C urea breath test 8 weeks after therapy. RESULTS: The eradication rate of first-line Maastricht therapy was 67% for intention-to-treat analysis (95% confidence interval [CI]: 58-75). Per-protocol and intention-to-treat eradication was achieved in 60.7% of patients (95%CI: 42-79) in the RAC group and in 85.7% of patients (95%CI: 73-98) in the RMT group (P = 0.03). Fifty-three percent of patients in the RAC and 50% of patients in the RMT group experienced at least one slight side-effect (P = 0.6). CONCLUSIONS: RMT is an effective and well-tolerated second-line therapy after H. pylori eradication failure from PPI, amoxicillin, and clarithromycin.  相似文献   
987.
OBJECTIVE: Thrombophilic gene mutations have been reported to be associated with the formation of portal vein thrombosis (PVT). This study aimed to investigate the role of thrombophilic gene mutations in cirrhotic patients with PVT. PATIENTS AND METHODS: A total of 74 cirrhotic patients (17 with PVT, 57 without PVT), and 19 non-cirrhotic patients with PVT and 80 healthy controls were included. Factor V Leiden G1691A, prothrombin G20210A and methylenetetrahydrofolate reductase C677T mutations were analysed by restriction fragment length polymorphism. RESULTS: Aetiologies and Child-Pugh distribution of cirrhotic patients with and without PVT were similar. Five of 17 (29%) of cirrhotic patients with PVT but only two of 57 (3.5%) of cirrhotics without PVT, five of 80 (6%) of controls and none of the 19 non-cirrhotic patients with PVT had factor V Leiden G1691A mutation (P<0.05). Prothrombin G20210A mutation was found in five (29%) cirrhotic patients with PVT while only two (3.5%) cirrhotic patients without PVT, one (5%) non-cirrhotic patient with PVT and two (2.5%) controls had this mutation (P<0.05). The frequency of the homozygote methylenetetrahydrofolate reductase 677C-T mutation was similar in all four groups. CONCLUSIONS: Inherited thrombophilic gene mutations appear to increase the risk of PVT formation in cirrhotic patients but not in patients without liver disease in a cohort of Turkish patients.  相似文献   
988.
989.
Objective The aim of this study was to investigate the ear involvement, especially at extended higher frequencies than those previously studied, in patients with ankylosing spondylitis (AS). Patients and methods We prospectively evaluated 45 consecutive patients with AS. All patients underwent a complete physical examination of the ear, nose, and throat and an audiologic evaluation that included pure-tone audiometry at conventional and extended high frequencies, the determination of a speech discrimination score and the uncomfortable loudness level, and impedance audiometry. Thirty healthy volunteers were included as controls. Results The mean age of the patients was 39.6 ± 9.1 years (range 19–63 years) and that of the controls was 10.6 ± 8.1 years (range 1–30 years). There was no statistically significant difference between the two groups with respect to conventional frequency air conduction threshold and bone conduction threshold. There was a statistically significant difference at 14,000–16,000 Hz at extended high frequencies in 32 patients with AS (71.1%) versus 12 controls (40%). At 14,000–16,000 Hz, eight patients demonstrated a sensorineural hearing loss caused by extraspinal involvement. There was a significant difference between the patients with or without extraspinal involvement, and a positive correlation was noted between the duration of disease and the hearing level at 10,000–16,000 Hz. Conclusion Sensorineural hearing loss, especially at extended high frequencies, is common in patients with AS and may be an extra-articular feature of that disease. A long duration of disease and extraspinal involvement are important parameters for ear involvement in patients with AS.  相似文献   
990.
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