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   64306篇
  免费   4749篇
  国内免费   1759篇
耳鼻咽喉   841篇
儿科学   1192篇
妇产科学   2217篇
基础医学   8095篇
口腔科学   1170篇
临床医学   6898篇
内科学   12018篇
皮肤病学   1220篇
神经病学   3980篇
特种医学   2631篇
外国民族医学   6篇
外科学   8600篇
综合类   4200篇
现状与发展   7篇
一般理论   11篇
预防医学   3515篇
眼科学   1415篇
药学   5357篇
  21篇
中国医学   1681篇
肿瘤学   5739篇
  2023年   525篇
  2022年   1321篇
  2021年   2155篇
  2020年   1312篇
  2019年   1624篇
  2018年   2000篇
  2017年   1518篇
  2016年   1567篇
  2015年   2335篇
  2014年   2923篇
  2013年   3397篇
  2012年   4868篇
  2011年   4746篇
  2010年   2991篇
  2009年   2629篇
  2008年   3609篇
  2007年   3596篇
  2006年   3442篇
  2005年   3152篇
  2004年   2851篇
  2003年   2732篇
  2002年   2372篇
  2001年   1846篇
  2000年   1609篇
  1999年   1336篇
  1998年   555篇
  1997年   460篇
  1996年   416篇
  1995年   377篇
  1994年   349篇
  1993年   243篇
  1992年   711篇
  1991年   583篇
  1990年   532篇
  1989年   485篇
  1988年   422篇
  1987年   425篇
  1986年   355篇
  1985年   295篇
  1984年   229篇
  1983年   191篇
  1982年   114篇
  1981年   122篇
  1980年   99篇
  1979年   205篇
  1978年   161篇
  1977年   103篇
  1976年   113篇
  1975年   102篇
  1974年   99篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
971.
972.
973.
In-training examinations (ITEs), arranged during residency training, evaluate the residents’ performances periodically. There is limited literature focusing on the effectiveness of resident ITEs in the format of simulation-based examinations, as compared to traditional oral or written tests. Our primary objective is to investigate the effectiveness and discriminative ability of high-fidelity simulation compared with other measurement formats in emergency medicine (EM) residency training program.This is a retrospective cohort study. During the 5-year study period, 8 ITEs were administered to 68 EM residents, and 253 ITE measurements were collected. Different ITE scores were calculated and presented as mean and standard deviation. The ITEs were categorized into written, oral, or high-fidelity simulation test forms. Discrimination of ITE scores between different training years of residency was examined using a one-way analysis of variance test.The high-fidelity simulation scores correlated to the progression of EM training, and residents in their fourth training year (R4) had the highest scores consistently, followed by R3, R2, and then R1. The oral test scores had similar results but not as consistent as the high-fidelity simulation tests. The written test scores distribution failed to discriminate the residents’ seniority. The high-fidelity simulation test had the best discriminative ability and better correlation between different EM residency training years comparing to other forms.High-fidelity simulation tests had the good discriminative ability and were well correlated to the EM training year. We suggest high-fidelity simulation should be a part of ITE in training programs associated with critical or emergency patient cares.  相似文献   
974.
Digestive Diseases and Sciences - Little is known about patient choice in treatment of eosinophilic esophagitis (EoE). Determine motivators and barriers to using common EoE therapies and describe...  相似文献   
975.
Rationale:A case of traumatic atlanto-axial rotatory subluxation (AARS), dens fracture, rupture of transverse atlantal ligament (TAL), and subaxial spinal cord injury without radiographic abnormality (SCIWORA) of Brown-Sequard syndrome has never been reported in a child.Patient concerns:A 7-year-old boy presented to hospital with torticollis, neck pain, and limited neck rotation after a seat-belt injury sustained during a car accident. Neurologic examination revealed right-side motor weakness and left-side sensory abnormality, known as Brown-Sequard syndrome.Diagnosis:Radiologic examinations revealed type II AARS (Fielding and Hawkins classification), increased atlanto-dental interval (ADI) of 4.5 mm due to a type 1B TAL rupture (Dickman classification), a displaced transverse dens fracture along with an ossiculum terminale, and an intramedullary hemorrhage on the right side of the spinal cord at C3–4.Interventions:The patient immediately received methylprednisolone, and his motor weakness and sensory abnormality gradually improved. At the same time, the patient underwent initial halter traction for 2 weeks, but he failed to achieve successful reduction and required manual reduction under general anesthesia.Outcomes:At the 7-month follow-up visit, radiologic examinations showed a corrected type II AARS that was well maintained and normalization of the ADI to 2 mm. The reduced transverse dens fracture was well maintained but still not united. All clinical symptoms were significantly improved, except the remaining motor weakness of the right upper extremity.Lessons:To the best of our knowledge, this is the first report of traumatic AARS, dens fracture, TAL rupture, and subaxial SCIWORA of Brown-Sequard syndrome in a child. Appropriate diagnosis and careful treatment strategy are required for successful management of complex cervical injuries in a child.  相似文献   
976.
Digestive Diseases and Sciences - Bile acid diarrhoea or BAD is a common but little recognised cause of chronic diarrhoea. Few of these patients in China have been diagnosed due to a lack of...  相似文献   
977.
Journal of Thrombosis and Thrombolysis - This study evaluated the risk of major bleeding associated with concomitant use of direct oral anticoagulant (DOAC) and anticancer drugs (ACDs), which share...  相似文献   
978.
目的分析武汉地区结直肠癌的临床病理特征及发病特点。方法回顾性分析1998年至2013年在武汉市第八医院收治的1 998例结直肠癌临床及病理资料,比较其主要症状、性别、年龄、肿瘤部位、组织类型、病理分级及临床病理分期的差异。结果本组最常见症状为血便及大便次数增多,好发部位主要位于直肠,组织学类型以管状腺癌腺癌为主,淋巴结转移与肿瘤的分化程度、侵袭程度及TNM分期有关。结论武汉地区男性结直肠癌的发病率显著高于女性,老年人仍是结直肠癌的高发人群,但青壮年也占相当大的比例。大部分患者就诊时已是中晚期。  相似文献   
979.
This study aimed to evaluate the efficacy of random-start controlled ovarian stimulation (COS) in cancer patients for emergency fertility preservation. In this retrospective comparative study, 22 patients diagnosed with cancer and 44 infertile women undergoing conventional in vitro fertilization (IVF) were included. In cancer patients, ovarian stimulation was started on the day of referral, irrespective of their menstrual cycle date. The control group was selected by age matching among women undergoing conventional IVF. COS outcomes were compared between groups. The number of total and mature oocytes retrieved and the oocyte maturity rate were higher in the random-start group than in the conventional-start group. However, duration of ovarian stimulation was longer in the random-start group (11.4 vs. 10.3 days, P = 0.004). The addition of letrozole to lower the estradiol level during COS did not adversely affect total oocytes retrieved. However, oocyte maturity rate was lower in cycles with letrozole than in cycles without letrozole (71.6% vs. 58.2%, P = 0.019). Our study confirms the feasibility and effectiveness of random-start COS in cancer patients.

Graphical Abstract

相似文献   
980.
Schwannomatosis is characterized by the development of multiple non-vestibular, non-intradermal schwannomas. Constitutional inactivating variants in two genes, SMARCB1 and, very recently, LZTR1, have been reported. We performed exome sequencing of 13 schwannomatosis patients from 11 families without SMARCB1 deleterious variants. We identified four individuals with heterozygous loss-of-function variants in LZTR1. Sequencing of the germline of 60 additional patients identified 18 additional heterozygous variants in LZTR1. We identified LZTR1 variants in 43% and 30% of familial (three of the seven families) and sporadic patients, respectively. In addition, we tested LZTR1 protein immunostaining in 22 tumors from nine unrelated patients with and without LZTR1 deleterious variants. Tumors from individuals with LZTR1 variants lost the protein expression in at least a subset of tumor cells, consistent with a tumor suppressor mechanism. In conclusion, our study demonstrates that molecular analysis of LZTR1 may contribute to the molecular characterization of schwannomatosis patients, in addition to NF2 mutational analysis and the detection of chromosome 22 losses in tumor tissue. It will be especially useful in differentiating schwannomatosis from mosaic Neurofibromatosis type 2 (NF2). However, the role of LZTR1 in the pathogenesis of schwannomatosis needs further elucidation.  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