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   163834篇
  免费   11479篇
  国内免费   782篇
耳鼻咽喉   1549篇
儿科学   4216篇
妇产科学   3037篇
基础医学   22089篇
口腔科学   3793篇
临床医学   16200篇
内科学   35129篇
皮肤病学   3104篇
神经病学   15801篇
特种医学   6396篇
外国民族医学   7篇
外科学   24880篇
综合类   2248篇
现状与发展   2篇
一般理论   156篇
预防医学   11930篇
眼科学   3367篇
药学   11075篇
  2篇
中国医学   250篇
肿瘤学   10864篇
  2023年   863篇
  2022年   1311篇
  2021年   2972篇
  2020年   2072篇
  2019年   2969篇
  2018年   3640篇
  2017年   2807篇
  2016年   3203篇
  2015年   3678篇
  2014年   5289篇
  2013年   7177篇
  2012年   11132篇
  2011年   11768篇
  2010年   6706篇
  2009年   6337篇
  2008年   10758篇
  2007年   11408篇
  2006年   10852篇
  2005年   11131篇
  2004年   10495篇
  2003年   9932篇
  2002年   9294篇
  2001年   1924篇
  2000年   1588篇
  1999年   1974篇
  1998年   2247篇
  1997年   1768篇
  1996年   1542篇
  1995年   1403篇
  1994年   1237篇
  1993年   1207篇
  1992年   1031篇
  1991年   1028篇
  1990年   835篇
  1989年   836篇
  1988年   745篇
  1987年   760篇
  1986年   685篇
  1985年   701篇
  1984年   779篇
  1983年   666篇
  1982年   827篇
  1981年   760篇
  1980年   649篇
  1979年   457篇
  1978年   430篇
  1977年   450篇
  1976年   401篇
  1975年   342篇
  1974年   312篇
排序方式: 共有10000条查询结果,搜索用时 31 毫秒
51.
52.
Introduction: Allergic rhinitis is a common condition with increasing prevalence and is associated with several comorbid disorders such as bronchial asthma and atopic dermatitis. If allergen avoidance is not possible, allergen-specific immunotherapy is the only causal treatment option.

Areas covered: This review focuses on current treatments and the future outlook for allergic rhinitis. Pharmacotherapy includes mast cell stabilizers, antihistamines, glucocorticosteroids (GCSs), leukotriene receptor antagonists, and nasal decongestants. Nasal GCSs are currently regarded as the most effective treatment and are considered first-line therapy together with non-sedating antihistamines. The new formulation MP29-02 combines the nasal GCS fluticasone propionate with azelastine in one single spray and has achieved greater improvements than those under monotherapy with modern GCSs or antihistamines. Furthermore, this review discusses allergen immunotherapy alone and in combination with modern monoclonal antibodies.

Expert opinion: Despite the variety of medications for allergic rhinitis, ranging from general symptomatic agents like GCSs or decongestants, to more specific ones like histamine receptor or leukotriene blockers, to causal therapy like immunotherapy, many patients still experience treatment failures or unsatisfactory results. The ultimate goal may be to endotype every downstream pathway separately in order to offer patients individualized, targeted therapy with specific antibodies against the respective pathway.  相似文献   

53.
54.

Background

Physicians treating nonvalvular atrial fibrillation (AF) assess stroke and bleeding risks when deciding on anticoagulation. The agreement between empirical and physician-estimated risks is unclear. Furthermore, the association between patient and physician sex and anticoagulation decision-making is uncertain.

Methods

We pooled data from 2 national primary care physician chart audit databases of patients with AF (Facilitating Review and Education to Optimize Stroke Prevention in Atrial Fibrillation and Coordinated National Network to Engage Physicians in the Care and Treatment of Patients with Atrial Fibrillation Chart Audit) with a combined 1035 physicians (133 female, 902 male) and 10,927 patients (4567 female and 6360 male).

Results

Male physicians underestimated stroke risk in female patients and overestimated risk in male patients. Female physicians estimated stroke risk well in female patients but underestimated the risk in male patients. Risk of bleeding was underestimated in all. Despite differences in risk assessment by physician and patient sex, > 90% of patients received anticoagulation across all subgroups. There was modest agreement between physician estimated and calculated (ie, CHADS2 score) stroke risk: Kappa scores were 0.41 (0.35-0.47) for female physicians and 0.34 (0.32-0.36) for male physicians.

Conclusions

Our study is the first to examine the association between patient and physician sex influences and stroke and bleeding risk estimation in AF. Although there were differences in agreement between physician estimated stroke risk and calculated CHADS2 scores, these differences were small and unlikely to affect clinical practice; further, despite any perceived differences in the accuracy of risk assessment by sex, most patients received anticoagulation.  相似文献   
55.
Fibrous dysplasia is a non‐neoplastic developmental process that affects the craniofacial bones, characterized by painless enlargement as a result of bone substitution by abnormal fibrous tissue. Postzygotic somatic activating mutations in the GNAS1 gene cause fibrous dysplasia and have been extensively investigated, as well as being helpful in the differential diagnosis of the disease. Fibrous dysplasia may involve one (monostotic) or multiple bones (polyostotic), sporadically or in association with McCune‐Albright syndrome, Jeffe‐Lichenstein syndrome, or Mazabreud syndrome. This review summarizes the current knowledge on fibrous dysplasia, emphasizing the value of integrating the understanding of its molecular pathogenesis with the clinical, radiological, and histopathological features. In addition, we address important aspects related to the differential diagnosis and patient management.  相似文献   
56.
The hepatitis C virus (HCV) is a pandemic human pathogen posing a substantial health and economic burden in both developing and developed countries. Controlling the spread of HCV through behavioural prevention strategies has met with limited success and vaccine development remains slow. The development of antiviral therapeutic agents has also been challenging, primarily due to the lack of efficient cell culture and animal models for all HCV genotypes, as well as the large genetic diversity between HCV strains. On the other hand, the use of interferon-α-based treatments in combination with the guanosine analogue, ribavirin, achieved limited success, and widespread use of these therapies has been hampered by prevalent side effects. For more than a decade, the HCV RNA-dependent RNA polymerase (RdRp) has been targeted for antiviral development. Direct acting antivirals (DAA) have been identified which bind to one of at least six RdRp inhibitor-binding sites, and are now becoming a mainstay of highly effective and well tolerated antiviral treatment for HCV infection. Here we review the different classes of RdRp inhibitors and their mode of action against HCV. Furthermore, the mechanism of antiviral resistance to each class is described, including naturally occurring resistance-associated variants (RAVs) in different viral strains and genotypes. Finally, we review the impact of these RAVs on treatment outcomes with the newly developed regimens.  相似文献   
57.
58.
Gender inequality is at the core of the HIV patterns that are evident in sub-Saharan Africa. Gender-based violence (GBV) and lack of economic opportunity are important structural determinants of HIV risk. We piloted a microfinance and health promotion intervention among social networks of primarily young men in Dar es Salaam. Twenty-two individuals participated in the microfinance component and 30 peer leaders were recruited and trained in the peer health leadership component. We collected and analysed observational data from trainings, monitoring data on loan repayment, and reports of peer conversations to assess the feasibility and acceptability of the intervention. Eighteen of the loan recipients (82%) paid back their loans, and of these 15 (83%) received a second, larger loan. Among the loan defaulters, one died, one had chronic health problems, and two disappeared, one of whom was imprisoned for theft. The majority of conversations reported by peer health leaders focused on condoms, sexual partner selection, and HIV testing. Few peer leaders reported conversations about GBV. We demonstrated the feasibility and acceptability of this innovative HIV and GBV prevention intervention. The lessons learned from this pilot have informed the implementation of a cluster-randomised trial of the microfinance and peer health leadership intervention.  相似文献   
59.
60.

Background

The efficacy of dexamethasone in extending the duration of local anaesthetic block is uncertain. In a randomised controlled triple blind crossover study in volunteers, we tested the hypothesis that neither i.v. nor perineurally administered dexamethasone prolongs the sensory block achieved with ropivacaine.

Methods

Ultrasound-guided ulnar nerve blocks (ropivacaine 0.75% wt/vol, 3 ml, with saline 1 ml with or without dexamethasone 4 mg) were performed on three occasions in 24 male volunteers along with an i.v. injection of saline 1 ml with or without dexamethasone 4 mg. The combinations of saline and dexamethasone were as follows: control group, perineural and i.v. saline; perineural group, perineural dexamethasone and i.v. saline; i.v. group, perineural saline and i.v. dexamethasone. Sensory block was measured using a VAS in response to pinprick testing. The duration of sensory block was the primary outcome and time to onset of sensory block the secondary outcome.

Results

All 24 subjects completed the trial. The median [inter-quartile range (IQR)] duration of sensory block was 6.87 (5.85–7.62) h in the control group, 7.37 (5.78–7.93) h in the perineural group and 7.37 (6.10–7.97) h in the i.v. group (P=0.61). There was also no significant difference in block onset time between the three groups.

Conclusion

Dexamethasone 4 mg has no clinically relevant effect on the duration of sensory block provided by ropivacaine applied to the ulnar nerve.

Clinical trial registration

DRKS, 00014604; EudraCT, 2018-001221-98.  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