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   1081篇
  免费   56篇
  国内免费   13篇
耳鼻咽喉   2篇
儿科学   11篇
妇产科学   10篇
基础医学   76篇
口腔科学   17篇
临床医学   93篇
内科学   181篇
皮肤病学   17篇
神经病学   40篇
特种医学   11篇
外国民族医学   1篇
外科学   74篇
综合类   49篇
预防医学   21篇
眼科学   14篇
药学   439篇
中国医学   33篇
肿瘤学   61篇
  2023年   9篇
  2022年   12篇
  2021年   21篇
  2020年   19篇
  2019年   38篇
  2018年   42篇
  2017年   32篇
  2016年   23篇
  2015年   29篇
  2014年   44篇
  2013年   165篇
  2012年   55篇
  2011年   58篇
  2010年   48篇
  2009年   51篇
  2008年   51篇
  2007年   59篇
  2006年   59篇
  2005年   49篇
  2004年   48篇
  2003年   52篇
  2002年   29篇
  2001年   24篇
  2000年   18篇
  1999年   7篇
  1998年   13篇
  1997年   16篇
  1996年   16篇
  1995年   19篇
  1994年   17篇
  1993年   6篇
  1992年   5篇
  1991年   3篇
  1990年   2篇
  1989年   6篇
  1988年   2篇
  1987年   1篇
  1981年   1篇
  1978年   1篇
排序方式: 共有1150条查询结果,搜索用时 187 毫秒
31.
Non‐steroidal anti‐inflammatory drugs (NSAIDs) are widely consumed among athletes worldwide in relation to muscle injury and soreness. This review aims to provide an overview of studies investigating their effects on skeletal muscle, in particular the repair processes in injured muscle. Muscle injury occurs in diverse situations and the nature of muscle injuries varies significantly, complicating extrapolations between experimental models and “real life.” Classical muscle strain injuries occur at the interphase between the muscle fibers and connective tissue, most often in the myotendinuous junction, whereas contusion or overload injury can damage both myofibers and intramuscular connective tissue. The role of NSAIDs in muscle repair is complicated by differences in injury models used, variables evaluated, and time point(s) selected for evaluations. While the temporal pattern of the influence of NSAIDs on muscle repair is difficult to settle on, it appears that a potential beneficial effect of NSAIDs in the early phase after injury is not maintained in the long term, or is even negated by a long‐term repair deficit. At the cellular level, evidence exists for a negative influence of NSAIDs on the muscle stem cell population (satellite cells). At a structural level, it is known that muscle connective tissue undergoes significant remodeling during muscle regeneration, but the potential of NSAID exposure to alter this response in humans needs investigation.  相似文献   
32.
ObjectiveDifferent measures are recommended to reduce pancreatitis after endoscopic retrograde cholangiopancreatography (ERCP). We conducted a study in patients with ERCP treated with rectal diclofenac or lactated Ringer's solution, or both interventions, to assess whether there is a decrease in the number of cases of post-ERCP pancreatitis.Material and methodsA mixed cohort study involving 1,896 patients from 2009 to 2018. Up to June 2012 without treatment (Group I). Subsequently, 100 mg of rectal diclofenac (Group II). Since 2016, lactated Ringer's solution 200 ml/hour during the procedure and 4 hours after it, in addition to 500 ml over 30 minutes when the pancreas was cannulated (Group III). Since 2017, lactated Ringer's solution plus Diclofenac (Group IV). There were 725 patients in group I, and 530, 227 and 414 patients in groups II, III and IV, respectively. Factors predisposing to post-ERCP pancreatitis and post-ERCP pancreatitis cases that were defined by consensus criteria have been collected.ResultsThere were 65 cases of post-ERCP pancreatitis (3.4%); 2.9%, 3.4%, 3.1% and 4.3% in groups I, II, III and IV, respectively (P = .640). In group I, there was 4.2% of post-ERCP pancreatitis in naïve papillae and 4%, 4.9% and 6.3% in groups II, III and IV, respectively (P = .585). The severity of post-ERCP pancreatitis and adverse effects were similar in all groups. 38.4% were high-risk patients. There were also no differences in post-ERCP pancreatitis in this group (P = .501).ConclusionIn this work, no benefit was obtained with diclofenac plus hydration in reducing the number and severity of cases of post-ERCP pancreatitis nor with the other prophylactic measures.  相似文献   
33.
34.

Aim

The aim of the study was to characterize the extent of indication bias resulting from the excessive use of NSAIDs on the days preceding a spontaneous abortion to relieve pain.

Methods

We used data from a retrospective cohort study assessing the risk for spontaneous abortions following exposure to NSAIDs. Three definitions of exposure for cases of spontaneous abortions were compared, from the first day of pregnancy until the day of spontaneous abortion and until 3 and 2 days before a spontaneous abortion. Statistical analysis was performed using multivariate time programmed Cox regression.

Results

A sharp increase was observed in the dispensation of indomethacin, diclofenac and naproxen, and a milder increase was found in the use of ibuprofen during the week before a spontaneous abortion. Non- selective COX inhibitors in general and specifically diclofenac and indomethacin were found to be associated with spontaneous abortions when the exposure period was defined until the day of spontaneous abortion (hazard ratio (HR) 1.15, 95% confidence interval (CI) 1.04, 1.28; HR 1.31, 95% CI 1.08, 1.59 and HR 3.33, 95% CI 2.09, 5.29, respectively). The effect disappears by excluding exposures occurring on the day before the spontaneous abortion for non-selective COX inhibitors and on the last week before the spontaneous abortion for indomethacin. In general, decreasing HRs were found with the exclusion of exposures occurring on the days immediately before the spontaneous abortion.

Conclusions

The increased use of NSAIDs during the last few days that preceded a spontaneous abortion to relieve pain associated with the miscarriage could bias studies assessing the association between exposure to NSAIDs and spontaneous abortions.  相似文献   
35.
Selective COX-2 inhibitors have been shown to produce fewer gastrointestinal adverse reactions than classical NSAIDs. Nevertheless, these new agents may worsen and delay the healing of experimentally induced gastric ulcers in animals. In this study, we compared the effects of a selective COX-2 inhibitor (celecoxib), a preferential COX-1 inhibitor (piroxicam), and a nonnarcotic analgesic (metamizol) on normal gastric mucosa of rats and, on the other hand, in a setting of preexisting acute gastric lesions induced by 0.6 N hydrochloric acid. Under normal conditions, only piroxicam produced appreciable gastric lesions. However, after acid challenge the three assayed drugs induced significant macroscopic and microscopic damage. Myeloperoxidase activity as an index of neutrophil infiltration was elevated with celecoxib and piroxicam on normal gastric mucosa. On inflamed mucosa, celecoxib augmented enzymatic activity at the lower dose, which was parallelled by an increase in the interleukin 1beta level. Acid instillaton produced a significant rise in PGE2 content at 7 hr. Drug treatment after acid challenge decreased prostaglandin values in all cases, although to a lesser extent than after single drug dose administration. COX-2 mRNA expression was visible 1 hr after acid application, whereas COX-2 protein could only be detected at 7 hr. Piroxicam increased both expression levels. All NSAIDs enhanced transforming growth factor alpha and epidermal growth factor receptor immunoreactivity around the acid-induced lesions. It is concluded that selective COX-2 inhibitors, like conventional NSAIDs, impair the healing of gastric damage, and therefore special attention should be paid in patients with gastric pathologies.  相似文献   
36.
Chan FK  Hung LC  Suen BY  Wong VW  Hui AJ  Wu JC  Leung WK  Lee YT  To KF  Chung SC  Sung JJ 《Gastroenterology》2004,127(4):1038-1043
BACKGROUND & AIMS: The gastric safety of cyclooxgenase-2 inhibitors and prophylactic antisecretory therapy in high-risk arthritis patients is unclear. We studied the ulcer incidence and factors predicting ulcer recurrence in a prospective, double-blinded trial. METHODS: We studied patients who presented with nonsteroidal anti-inflammatory drug-associated ulcer bleeding. After ulcer healing, patients who were negative for Helicobacter pylori were randomly assigned to celecoxib 200 mg twice a day plus omeprazole placebo once daily or diclofenac 75 mg twice daily plus omeprazole 20 mg once daily for 6 months. Patients underwent endoscopy if they developed recurrent bleeding. Those without recurrent events underwent endoscopy at their last follow-up visit. RESULTS: Two hundred eighty-seven patients were enrolled; 24 had recurrent gastrointestinal complications. Among 259 patients without events, 222 underwent endoscopy (116 received celecoxib and 106 received diclofenac plus omeprazole). The probability of recurrent ulcers in 6 months was 18.7% in the celecoxib group and 25.6% in the diclofenac plus omeprazole group (difference, -6.7%; 95% CI: -17.8% to 3.9%) (P = 0.21). Combining bleeding and endoscopic ulcers, 24.1% in the celecoxib group and 32.3% in the diclofenac plus omeprazole group had recurrent ulcers in 6 months (difference, -8.2%; 95% CI: -19.5% to 2.9%) (P = 0.15). Treatment-induced significant dyspepsia (hazard ratio, 5.3; 95% CI: 2.6-10.8), age > or =75 (hazard ratio, 2.0; 95% CI: 1.1-3.5), and comorbidity (hazard ratio, 2.1; 95% CI: 1.2-3.7) independently predicted ulcer recurrence. CONCLUSIONS: Among patients with previous ulcer bleeding, neither celecoxib nor diclofenac plus omeprazole adequately prevents ulcer recurrence. Treatment-induced significant dyspepsia is an indication for endoscopic evaluation.  相似文献   
37.
Helicobacter pylori infection: A clinical overview   总被引:1,自引:0,他引:1  
BACKGROUND: Helicobcater pylori colonizes the stomach of more than half of the world's population, and the infection continues to play a key role in the pathogenesis of a number of gastroduodenal diseases. Colonization of the gastric mucosa with Helicobcater pylori results in the development of chronic gastritis in all infected individuals and in a subset of patients chronic gastritis progresses to complications (i.e. ulcer disease, gastric neoplasias, some distinct extragastric disorders). The clinical outcome of the disease is dependent on many variables, including Helicobcater pylori genotype, innate host physiology, genetic predisposition and environmental factors. Helicobcater pylori eradication decreases the incidence of gastroduodenal ulcer and prevents its recurrence. Helicobcater pylori eradication for gastric cancer prevention has been suggested by preclinical research and clinical trials, showing even reversibility of precancerous lesions (atrophic gastritis and intestinal metaplasia) after Helicobcater pylori eradication. AIMS: To review the current literature about H. pylori and its related pathologies. CONCLUSION: At present, several clinical manifestations are recognized to be causally linked to Helicobcater pylori infection, and most of them can be cured by Helicobcater pylori eradication. Besides the relationship of Helicobcater pylori and gastroduodenal diseases, it has been well established that Helicobcater pylori infection is also involved in some extragastrointestinal diseases.  相似文献   
38.
39.
Alzheimer's disease (AD) neuropathology is characterized by innate immune activation primarily through prostaglandin E2 (PGE2) signaling. Dedicator of cytokinesis 2 (DOCK2) is a guanyl nucleotide exchange factor expressed exclusively in microglia in the brain and is regulated by PGE2 receptor EP2. DOCK2 modulates microglia cytokine secretion, phagocytosis, and paracrine neurotoxicity. EP2 ablation in experimental AD results in reduced oxidative damage and amyloid beta (Aβ) burden. This discovery led us to hypothesize that genetic ablation of DOCK2 would replicate the anti-Aβ effects of loss of EP2 in experimental AD. To test this hypothesis, we crossed mice that lacked DOCK2 (DOCK2 −/−), were hemizygous for DOCK2 (DOCK2 +/−), or that expressed two DOCK2 genes (DOCK2 +/+) with APPswe-PS1Δe9 mice (a model of AD). While we found no DOCK2-dependent differences in cortex or in hippocampal microglia density or morphology in APPswe-PS1Δe9 mice, cerebral cortical and hippocampal Aβ plaque area and size were significantly reduced in 10-month-old APPswe-PS1Δe9/DOCK2 −/− mice compared with APPswe-PS1Δe9/DOCK2 +/+ controls. DOCK2 hemizygous APPswe-PS1Δe9 mice had intermediate Aβ plaque levels. Interestingly, soluble Aβ42 was not significantly different among the three genotypes, suggesting the effects were mediated specifically in fibrillar Aβ. In combination with earlier cell culture results, our in vivo results presented here suggest DOCK2 contributes to Aβ plaque burden via regulation of microglial innate immune function and may represent a novel therapeutic target for AD.  相似文献   
40.
OBJECTIVES: To evaluate the use of starting doses of rofecoxib and nabumetone in patients with osteoarthritis (OA) of the knee. DESIGN: A 6-week, randomized, parallel-group, double-blind, placebo-controlled study. SETTING: One hundred thirteen outpatient sites in the United States. PARTICIPANTS: A total of 1,042 male and female patients aged 40 and older with OA of the knee (>6 months). INTERVENTIONS: Rofecoxib 12.5 mg once a day (n=424), nabumetone 1,000 mg once a day (n=410), or placebo (n=208) for 6 weeks. MEASUREMENTS: The primary efficacy endpoint was patient global assessment of response to therapy (PGART) over 6 weeks, which was also specifically evaluated over the first 6 days. The main safety measure was adverse events during the 6 weeks of treatment. RESULTS: The percentage of patients with a good or excellent response to therapy as assessed using PGART at Week 6 was significantly higher with rofecoxib (55.4%) than nabumetone (47.5%; P=.018) or placebo (26.7%; P<.001 vs rofecoxib or nabumetone). Median time to first report of a good or excellent PGART response was significantly shorter in patients treated with rofecoxib (2 days) than with nabumetone (4 days, P=.002) and placebo (>5 days, P<.001) (nabumetone vs placebo; P=.007). The safety profiles of rofecoxib and nabumetone were generally similar, including gastrointestinal, hypertensive, and renal adverse events. CONCLUSION: Rofecoxib 12.5 mg daily demonstrated better efficacy over 6 weeks of treatment and quicker onset of OA efficacy over the first 6 days than nabumetone 1,000 mg daily. Both therapies were generally well tolerated.  相似文献   
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