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   39309篇
  免费   3304篇
  国内免费   809篇
耳鼻咽喉   191篇
儿科学   580篇
妇产科学   838篇
基础医学   2180篇
口腔科学   1479篇
临床医学   11451篇
内科学   2596篇
皮肤病学   165篇
神经病学   3541篇
特种医学   1286篇
外国民族医学   5篇
外科学   8268篇
综合类   3292篇
一般理论   4篇
预防医学   1399篇
眼科学   109篇
药学   2876篇
  59篇
中国医学   2181篇
肿瘤学   922篇
  2024年   89篇
  2023年   1070篇
  2022年   1353篇
  2021年   2165篇
  2020年   2181篇
  2019年   2138篇
  2018年   1950篇
  2017年   1803篇
  2016年   1586篇
  2015年   1485篇
  2014年   3025篇
  2013年   3535篇
  2012年   2032篇
  2011年   2256篇
  2010年   1809篇
  2009年   1694篇
  2008年   1867篇
  2007年   1607篇
  2006年   1468篇
  2005年   1150篇
  2004年   1009篇
  2003年   837篇
  2002年   730篇
  2001年   620篇
  2000年   485篇
  1999年   479篇
  1998年   383篇
  1997年   363篇
  1996年   278篇
  1995年   256篇
  1994年   236篇
  1993年   189篇
  1992年   190篇
  1991年   148篇
  1990年   93篇
  1989年   104篇
  1988年   87篇
  1987年   96篇
  1986年   94篇
  1985年   96篇
  1984年   75篇
  1983年   61篇
  1982年   66篇
  1981年   53篇
  1980年   39篇
  1979年   25篇
  1978年   16篇
  1977年   11篇
  1976年   17篇
  1975年   13篇
排序方式: 共有10000条查询结果,搜索用时 234 毫秒
991.
Intractable cancer pain not amenable to standard oral or parenteral analgesics is a horrifying truth in 10–15% of patients. Interventional pain management techniques are an indispensable arsenal in pain physician''s armamentarium for severe, intractable pain and can be broadly classified into neuroablative and neuromodulation techniques. An array of neurolytic techniques (chemical, thermal, or surgical) can be employed for ablation of individual nerve fibers, plexuses, or intrathecalneurolysis in patients with resistant pain and short life-expectancy. Neuraxial administration of drugs and spinal cord stimulation to modulate or alter the pain perception constitutes the most frequently employed neuromodulation techniques. Lately, there is a rising call for early introduction of interventional techniques in carefully selected patients simultaneously or even before starting strong opioids. After decades of empirical use, it is the need of the hour to head towards professionalism and standardization in order to secure credibility of specialization and those practicing it. Even though the interventional management has found a definite place in cancer pain, there is a dearth of evidence-based practice guidelines for interventional therapies in cancer pain. This may be because of paucity of good quality randomized controlled trials (RCTs) evaluating their safety and efficacy in cancer pain. Laying standardized guidelines based on existing and emerging evidence will act as a foundation step towards strengthening, credentialing, and dissemination of the specialty of interventional cancer pain management. This will also ensure an improved decision-making and quality of life (QoL) of the suffering patients.  相似文献   
992.
目的:观察自拟乳痛方治疗乳腺增生的疗效。方法选取2013年1月~12月来我院就诊的69例乳腺增生患者,所有患者均采用自拟乳痛方进行治疗,治疗时间1~7个疗程不等,记录乳房肿块评分以及乳房疼痛评分。结果共治疗69例患者,其中治愈30例;好转33例;无效6例;总有效率91.30%。结论自拟乳痛方治疗乳腺增生效果明显,安全可靠,值得推广。  相似文献   
993.
目的:本文就一次性根充法应用于牙髓炎临床治疗中的价值进行了浅显的研究和探析。方法选择我单位口腔中心自2013年7月~2014年7月期间收治的牙髓炎患者68例,将其平均分为观察组和对照组,两组患者均34例,观察组行一次性根充法治疗,对照组行分次根充法治疗,对两组患者的治疗效果,疼痛程度及舒适程度进行观察和统计。结果观察组患者治疗总有效率明显高于对照组患者(<0.05);观察组患者疼痛评分明显低于对照组患者(<0.05);观察组患者舒适评分明显高于对照组患者(<0.05)。结论一次性根充法应用于牙髓炎临床治疗中的效果显著,有效减轻了患者的疼痛程度,值得推广。  相似文献   
994.
目的:探究产科手术后的切口疼痛的临床护理措施。方法选择2013年4月~2014年3月在我院接受妇产科手术的226例患者作为研究对象,观察其手术后疼痛情况,并给予针对性的药物镇痛及心理护理进行有效的疼痛干预。结果减轻了患者手术后的疼痛感,缩短住院时间的同时,还避免了并发症的发生。结论对妇产科术后出现的疼痛进行综合性处理,可以有效促进患者渡过手术后的恢复期。  相似文献   
995.
Aortic dissection is extremely rare in children. Although it usually presents with severe chest pain, atypical clinical presentations mimicking various illnesses may cause misdiagnosis. In this report, the case of a 14‐year‐old boy with symptoms suggestive of acute abdomen, which was finally diagnosed as aortic dissection, is discussed.  相似文献   
996.
Objective: To identify correlates of major complications and mortality in patients presenting to the emergency department with chest pain and more than bibasilar rales. Design: Prospective cohort study. Setting: The emergency departments of three university and four community hospitals. Patients: Five hundred patients more than 30 years of age presenting to the emergency departments between 1984 and 1985 with a chief complaint of chest pain not explained by obvious trauma or chest x-ray abnormalities, and more than bibasilar rales on physical examination. Measurements and main results: A standard data form was used to collect the history, physical examination, vital sign, and electrocardiographic findings. Chart review was carried out to record complications and mortality. One hundred eleven (22%) of the patients had a major complication (ventricular fibrillation, Mobitz II heart block, complete heart block, atrioventricular dissociation, cardiogenic shock, cardiac arrest, endotracheal intubation, intra-aortic balloon pump) or died, 160 (32%) were diagnosed as having myocardial infarction, and 58 (12%) died. Of those patients who had major complications or who died, the first complication occurred within six hours of hospital admission for 32% of the patients and within 24 hours for 47% of the patients. Univariate correlates (p<0.10) of a major complication or death were entered into a stepwise logistic regression model. In the multivariate model, ST elevation or Q waves not known to be old [adjusted odds ratio (OR) 5.8, 95% confidence interval (CI) 3.0–11.1], ST-T changes of ischemia not known to be old (OR 2.6, 95% CI 1.5–4.6), systolic blood pressure ≤ 120 mm Hg (OR 3.2, 95% CI 1.9–5.6), and age >70 years (OR 1.8, 95% CI 1.1–3.0) were correlates of a major complication or death. Conclusion: For patients presenting to the emergency department with chest pain and more than bibasilar rales, major electrocardiographic changes, systolic blood pressure ≤ 120 mm Hg, and age >70 years were correlated with a higher risk of a major complication or death. Supported by a grant (83102-2H) from the John A. Hartford Foundation, New York. Dr. Lee is the recipient of an Established Investigator Award (900119) from the American Heart Association.  相似文献   
997.
We report a patient with hereditary angioedema (HAE) presenting with skin edema and abdominal pain. Laboratory examination showed reduced levels of CH50, C2, C4, and C1 inhibitor (C1-INH). Abdominal computed tomography (CT) showed marked mesenteric edema and wall thickening of the duodenum and transverse colon. Acute abdominal pain is common in HAE and is difficult to distinguish from surgical emergency. Massive mesenteric edema on CT is a rare, but specific, sign suggesting HAE.  相似文献   
998.
Functional bowel disorders (FBDs) are the most common gastrointestinal (GI) disorders seen by gastroenterologists and primary care physicians. The disorders affect patients functioning and quality of life (QOL) and are associated with significant healthcare burden. The current theory regarding the development of FBDs suggests brain-gut axis dysfunctions associated abnormal GI motility and sensation. Recent data suggest that alterations in the intestinal microbiota may have a role in the pathogenesis of FBDs; or at least have the potential to affect intestinal functions that are thought to be relevant to the development of functional GI symptoms. This has led to growing interest of healthcare providers and patients in targeting the intestinal microbiota for the treatment of FBDs. In this article we discuss the potential role probiotic interventions in the treatment of FBDs. We review the evidence from pre-clinical and clinical studies and discuss the current recommendations for the use of probiotics for FBDs in clinical practice.  相似文献   
999.
The presence and actions of opioid receptors in bovine pineal gland   总被引:3,自引:0,他引:3  
The mammalian pineal gland and its main hormone, melatonin, working in conjunction with the hypothalamic suprachiasmatic nuclei, synchronize circadian rhythm and hence refine numerous physiological and biochemical parameters. An interaction among melatonin, opioids, and analgesia has been suspected for many years, since during nighttime, when the level of melatonin is high, the mammals are less sensitive to pain. In studying this phenomenon further, we have identified a single population of opioid receptors in the bovine pineal gland using [3H]-diprenorphine and other ligands. The receptors have a dissociation equilibrium constant (Kd) of 1.36 +/- 0.31 nM and a density (Bmax) of 17.93 +/- 5.22 fmol/mg protein. In competitive experiments, the concentration of drugs required to inhibit 50% of the [3H]-diprenorphine binding (IC50) in descending order of potency was found to be naltrexone > fentanyl > naloxone > nalbuphine > morphine > nalorphine > DAGO > dynorphin > metenkephalin. In order to delineate the function of the opioid system in the pineal gland, the effects of both opioid receptor agonists and antagonists on the basal activity of N-acetyltransferase were examined in the bovine pineal explants in culture. Morphine, an opioid receptor agonist, increased significantly the activity of N-acetyltransferase in a dose-dependent fashion. In addition, the stimulatory effect of morphine was inhibited by naloxone, an opioid receptor antagonist. The results of these studies indicate the existence of pineal opioid receptors, which play a pivotal role in the synthesis of melatonin and its action in synchronizing pineal events.  相似文献   
1000.
Objective: To estimate the association between gestational diabetes mellitus (GDM) and adverse pregnancy and neonatal outcomes in Denmark.

Methods: A population-based cohort study including all singleton pregnancies in Denmark from 2004 to 2010 (n?=?403?092). Maternal complications during pregnancy and delivery and fetal complications were classified according to the International Classification of Diseases 10th Revision.

Results: The final study population consisted of 398?623 women. Of these, 9014 (2.3%) had GDM. Data were adjusted for maternal age, parity, smoking, gestational age, birth weight, BMI, gender of the fetus and calendar year. The risk of preeclampsia, caesarean section (both planned and emergency) and shoulder dystocia was increased in women with GDM. In the unadjusted analysis, the risk of thrombosis was increased by a factor 2 in the GDM patients, but in the adjusted analysis this association disappeared. Post-partum hemorrhage was similar in the two groups. The GDM women had an increased risk of giving birth to a macrosomic neonate although the unadjusted analysis did not show any difference between the two groups. Low Apgar score was increased in the GDM, but this association disappeared in the adjusted analysis. Stillbirth was comparable in the two groups.

Conclusions: Women with GDM still have increased incidence of obstetric and neonatal complications, which could imply that treatment of women with GDM should be tightened.  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