首页 | 官方网站   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   6311篇
  免费   269篇
  国内免费   58篇
医药卫生   6638篇
  2022年   17篇
  2021年   87篇
  2020年   41篇
  2019年   51篇
  2018年   70篇
  2017年   70篇
  2016年   88篇
  2015年   90篇
  2014年   125篇
  2013年   159篇
  2012年   303篇
  2011年   304篇
  2010年   204篇
  2009年   177篇
  2008年   320篇
  2007年   372篇
  2006年   333篇
  2005年   402篇
  2004年   393篇
  2003年   385篇
  2002年   389篇
  2001年   159篇
  2000年   201篇
  1999年   167篇
  1998年   121篇
  1997年   103篇
  1996年   82篇
  1995年   68篇
  1994年   70篇
  1993年   67篇
  1992年   124篇
  1991年   133篇
  1990年   98篇
  1989年   96篇
  1988年   89篇
  1987年   95篇
  1986年   69篇
  1985年   61篇
  1984年   73篇
  1983年   57篇
  1982年   40篇
  1981年   16篇
  1980年   20篇
  1979年   20篇
  1978年   22篇
  1977年   22篇
  1976年   20篇
  1975年   16篇
  1974年   18篇
  1967年   15篇
排序方式: 共有6638条查询结果,搜索用时 109 毫秒
1.
Seven patients with advanced lateral oropharyngeal cancer (T3N2bM0, or T4N2bM0) underwent transoral lateral oropharyngectomy (TLO) with reconstruction performed through set-back tongue flap and polyglycolic acid (PGA) sheet. TLO was performed following en bloc resection of tumors using endoscopy. To cover the resulting defect in the lateral oropharyngeal wall, the set-back tongue flap was moved posteriorly and laterally to the area of the tongue base and lateral pharyngeal wall. The tip of the set-back tongue flap was sutured to the lateral pharynx to reconstruct the elevated tongue base and altered anterior pillar. The defect on the floor of the mouth was reconstructed using a PGA sheet. Following surgery, the mean observation period was 24 months. The mean operating time was 4 h and 2 min, with an average blood loss of 68.1 ml. All oral intake resumed on the first postoperative day via gastric tube. The mean gastric tube removal time was 1.6 postoperative days as a result of sufficient oral intake. None of the patients received postoperative radiotherapy or displayed evidence of tumor recurrence. We conclude that this novel procedure is highly effective for treating advanced oropharyngeal cancer as it demonstrates good prognostic and functional outcomes.  相似文献   
2.
1. The relationship between work-rate and the antihypertensive effect of exercise in hypertensives, and the mechanism of that effect, were investigated by a crossover clinical trial. 2. Ten mild hypertensives were randomly divided into two groups. One group performed low work-rate exercise (LWE) on a cycle ergometer for 10 weeks (blood lactate threshold; ~50% of maximum oxygen consumption [V?O2max]). After a 10 week interval without exercise training, these subjects were then switched to a high work-rate exercise (HWE) regimen (4 mmol/ L of blood lactate; ~75% of V?O2max) for another 10 weeks. In the other group, the order of exercise training was reversed. Since two patients withdrew from the protocol during HWE periods, statistical analysis was performed on the data from the remaining eight patients. There were no order effects observed in any of the data from the two groups. 3. During both LWE and HWE, resting blood pressure (BP) fell significantly after the initiation of exercise therapy (P<0.05). Furthermore, the overall effects of 10 weeks of LWE and HWE on BP were not significantly different. 4. The work-rate at the lactate threshold, which reflects physical fitness, had increased significantly by 16 W (P<0.01) after the LWE period and by 11 W (P<0.01) after the HWE. 5. During the LWE period, changes in haemodynamic and humoral variables were not significant, except for a reduction in plasma norepinephrine at week 10 (P<0.05). In the HWE period, changes in haemodynamic and humoral variables were not significant. 6. Based on these findings, LWE is recommended for mild hypertensives because of its safety.  相似文献   
3.
H Sasaki  K Sudoh  K Hamada  T Hamada  K Tashiro 《Neurology》1987,37(7):1258-1262
We studied two patients with nonfamilial olivopontocerebellar atrophy with skeletal myoclonus. Palatal or skeletal myoclonus is probably not a coincidental finding but another manifestation of the underlying disease. In both cases, the myoclonus was suppressed by administration of trihexyphenidyl, indicating a cholinergic disorder.  相似文献   
4.
5.
Ohne ZusammenfassungMit 26 Textabbildungen.  相似文献   
6.
OBJECTIVES: We investigated whether the Na+-H+ exchange inhibitor, HOE642 (Hoe), and/or the Na channel blocker, mexiletine (Mex), enhance a cardioprotective effect on St. Thomas' Hospital cardioplegic solution (STS) to clarify the mechanism by which intracellular Na+ is accumulated after cardioplegic arrest. MATERIALS AND METHODS: Isolated working rat hearts were perfused with Krebs-Henseleit bicarbonate buffer (KHBB). The hearts were then arrested with STS and subjected to normothermic global ischemia (30 min). This was followed by Langendorff reperfusion (15 min) and then a working reperfusion (20 min). In study A, we added Hoe (5, 10, and 20 microM), Mex (70 microM), or a combination of Hoe (20 microM) and Mex (70 microM), to STS. In study B, we added Hoe (20 microM), Mex (70 microM), or a combination of Hoe (20 microM) and Mex (70 microM) to KHBB during the first 3 min of Langendorff reperfusion. RESULTS: In study A, the addition of Hoe (10 and 20 microM) to STS showed a significantly greater postischemic recovery of cardiac output compared to the control group [63.1+/-5.7% (10 microM), 62.7+/-4.7% (20 microM), and 55.5+/-4.6% (control), respectively]. The postischemic recovery of cardiac output was significantly greater in the group of the combined addition (Hoe and Mex) to STS than that in the control, 20 microM Hoe, 70 microM Mex groups [70.3+/-3.7 (Hoe and Mex), 55.5+/-4.6% (control), 62.7+/-4.7% (Hoe 20 microM), and 60.2+/-4.7% (Mex 70 microM), respectively]. The myocardial water content in the postischemic period was 565.1+/-29.1, 525.8+/-2.9, 509.4+/-19.6, and 532.2+/-20.1; it was 497.3+/-9.1 mL/100 g dry weight in the control; and 10 microM Hoe, 20 microM Hoe, and 70 microM Mex in the combined use groups. In study B, there was no significant difference in the postischemic recovery of cardiac output in all experimental groups. CONCLUSION: The combined use of the Na+-H+ exchange inhibitor and Na+ channel blocker during cardioplegia may achieve a superior cardioprotective effect on myocardial damage because of ischemia and reperfusion.  相似文献   
7.
Tumor recurrence after liver transplantation still remains a significant problem in patients with hepatocellular carcinoma. The small GTPase Rho/Rho-associated kinase (ROCK) pathway is involved in the motility and invasiveness of cancer cells. We investigated whether tacrolimus activated the Rho/ROCK signal pathway to promote the invasiveness of rat hepatocellular carcinoma cells. We also investigated whether the ROCK inhibitor Y-27632 suppressed tumor recurrence after experimental liver transplantation in a rat hepatocellular carcinoma model. Orthotopic liver transplantation was performed in hepatocellular carcinoma cell line McA-RH7777-bearing rats. Tacrolimus was administered to liver transplant rats and these rats were divided into two groups: the Y-27632-treated (10 mg/kg, for 28 days) group and the Y-27632-untreated group. Tacrolimus enhanced the cancer cell migration and stimulated phosphorylation of the myosin light chain (MLC), a downstream effector of Rho/ROCK signaling. Y-27632 suppressed the cancer cell migration and tacrolimus-induced MLC phosphorylation. Suppression of tumor recurrence after liver transplantation and significant prolongation of survival were observed in the Y-27632-treated rats in comparison with theY-27632-untreated rats. Tacrolimus stimulates the Rho/ROCK signal pathway to enhance the invasiveness of hepatocellular carcinoma, and the ROCK inhibitor Y-27632 can be used as a new antimetastatic agent for the prevention of tumor recurrence after liver transplantation.  相似文献   
8.
9.
We evaluated nitric oxide induction in antitumor therapy consisting of anti–CD3 monoclonal antibody (anti–CD3) and interleukin–2 (IL–2), then determined the effect of nitric oxide reduction with L–NG–monomethyl arginine (LNMA) on the therapeutic methods. Female C57BL/6 mice, MCA102 (a non immunogenic, NK–resistant murine fibrosarcoma cell line), and 145–2C11 (hamster anti–murine–CD3 mAb) were utilized in an experimental hepatic metastasis model developed by injecting a tumor cell suspension into the spleen of mice. A marked increase in serum NO2+ NO1 was observed at 19 hours after anti–CD3 (10 μ, IV) and additional IL–2 administrations (40times101 U, twice, If) induced a further increase. The NO2, + NO3- elevation in spot urine in the combination therapy was not suppressed with LNMA at a dose of 100 μg/h but was significantly lowered at 300 μg/h. The efficacy of the anti–CD3 + IL–2 therapy was not diminished by LNMA administration either at 100 μg/h or at 300 μg/h.  相似文献   
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-23

京公网安备 11010802026262号