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   193796篇
  免费   13508篇
  国内免费   4548篇
耳鼻咽喉   1368篇
儿科学   2687篇
妇产科学   3073篇
基础医学   23966篇
口腔科学   3379篇
临床医学   14181篇
内科学   26101篇
皮肤病学   2234篇
神经病学   12133篇
特种医学   6663篇
外国民族医学   2篇
外科学   20532篇
综合类   26257篇
现状与发展   21篇
一般理论   8篇
预防医学   15221篇
眼科学   2306篇
药学   25841篇
  55篇
中国医学   12644篇
肿瘤学   13180篇
  2024年   354篇
  2023年   2365篇
  2022年   5514篇
  2021年   7970篇
  2020年   6420篇
  2019年   6448篇
  2018年   6558篇
  2017年   7022篇
  2016年   7021篇
  2015年   6706篇
  2014年   7936篇
  2013年   11813篇
  2012年   9518篇
  2011年   11573篇
  2010年   7368篇
  2009年   7670篇
  2008年   9094篇
  2007年   10120篇
  2006年   9571篇
  2005年   8861篇
  2004年   7581篇
  2003年   6762篇
  2002年   5319篇
  2001年   4821篇
  2000年   4025篇
  1999年   3445篇
  1998年   2709篇
  1997年   2829篇
  1996年   2537篇
  1995年   2208篇
  1994年   2105篇
  1993年   1777篇
  1992年   1647篇
  1991年   1538篇
  1990年   1323篇
  1989年   1082篇
  1988年   1031篇
  1987年   945篇
  1986年   870篇
  1985年   1257篇
  1984年   1011篇
  1983年   747篇
  1982年   791篇
  1981年   638篇
  1980年   628篇
  1979年   496篇
  1978年   314篇
  1977年   272篇
  1976年   256篇
  1975年   209篇
排序方式: 共有10000条查询结果,搜索用时 31 毫秒
91.
《Vaccine》2019,37(31):4310-4317
ONRAB® is a human adenovirus rabies glycoprotein recombinant vaccine developed to control rabies in wildlife. To support licensing and widespread use of the vaccine, safety studies are needed to assess its potential residual impact on wildlife populations. We examined the persistence of the ONRAB® vaccine virus in captive rabies vector and non-target mammals. This research complements work on important rabies vector species (raccoon, striped skunk, and red fox) but also adds to previous findings with the addition of some non-target species (Virginia opossum, Norway rats, and cotton rats) and a prolonged period of post vaccination monitoring (41 days). Animals were directly inoculated orally with the vaccine and vaccine shedding was monitored using quantitative real-time PCR applied to oral and rectal swabs. ONRAB® DNA was detected in both oral and rectal swabs from 6 h to 3 days post-inoculation in most animals, followed by a resurgence of shedding between days 17 and 34 in some species. Overall, the duration over which ONRAB® DNA was detectable was shorter for non-target mammals, and by day 41, no animal had detectable DNA in either oral or rectal swabs. All target species, as well as cotton rats and laboratory-bred Norway rats, developed robust humoral immune responses as measured by competitive ELISA, with all individuals being seropositive at day 31. Similarly, opossums showed good response (89% seropositive; 8/9), whereas only one of nine wild caught Norway rats was seropositive at day 31. These results support findings of other safety studies suggesting that ONRAB® does not persist in vector and non-target mammals exposed to the vaccine. As such, we interpret these data to reflect a low risk of adverse effects to wild populations following distribution of ONRAB® to control sylvatic rabies.  相似文献   
92.

Objective

To determine whether differences in combination DTaP vaccine types at 2, 4 and 6?months of age were associated with mortality (all-cause or non-specific), within 30?days of vaccination.

Design

Observational nationwide cohort study.

Setting

Linked population data from the Australian Childhood Immunisation Register and National Death Index.

Participants

Australian infants administered a combination trivalent, quadrivalent or hexavalent DTaP vaccine (DTaP types) between January 1999 and December 2010 at 2, 4 and 6?months as part of the primary vaccination series. The study population included 2.9, 2.6, & 2.3?million children in the 2, 4 and 6?month vaccine cohorts, respectively.

Main outcome measures

Infants were evaluated for the primary outcome of all-cause mortality within 30?days. A secondary outcome was non-specific mortality (unknown cause of death) within 30?days of vaccination. Non-specific mortality was defined as underlying or other cause of death codes, R95 ‘Sudden infant death syndrome’, R96 ‘Other sudden death, cause unknown’, R98 ‘Unattended death’, R99 ‘Other ill-defined and unspecified cause of mortality’ or where no cause of death was recorded.

Results

The rate of 30?day all-cause mortality was low and declined from 127.4 to 59.3 deaths per 100,000 person-years between 2 and 6?month cohorts. When compared with trivalent DTaP vaccines, no elevated risk in all-cause or non-specific mortality was seen with any quadrivalent or hexavalent DTaP vaccines, for any cohort.

Conclusion

Use of routine DTaP combination vaccines with differing disease antigens administered during the first six months of life is not associated with infant mortality.  相似文献   
93.
Syphilis is a sexually transmitted disease caused by Treponema pallidum. Syphilitic aortitis might coexist in a dysfunctional aortic valve, but the etiology remains unclear, because microbiological diagnosis is difficult. A 62-year-old man with low-grade fever was diagnosed with aortitis and infective endocarditis, due to Treponema pallidum infection, using polymerase chain reaction analysis. This case suggests that syphilis might cause infective endocarditis.  相似文献   
94.
95.
96.
BackgroundSingle-anastomosis duodeno-ileal bypass (SADI) and the one-anastomosis gastric bypass (OAGB) are 2 revisional procedures to address the problem of weight recidivism after laparoscopic sleeve gastrectomy (LSG).ObjectivesTo evaluate the efficacy and safety of SADI and OAGB as revisional bariatric surgery (RBS) in initially super-obese patients (body mass index [BMI] >50 kg/m2).SettingAcademic hospital, bariatric center of excellence, Germany.MethodsObservational study of outcomes in 84 initially super-obese patients who had undergone RBS after LSG (SADI n = 42, OAGB n = 42) between July 2013 and April 2018. Follow-up examinations were performed at 1, 6, 12, 24, and 36 months after RBS. The variables analyzed included time between LSG and RBS, BMI, excess weight loss, total weight loss, operation time, and complications.ResultsThe time interval between LSG and RBS was 45.5 ± 22.8 and 43.5 ± 24.2 months for SADI and OAGB, respectively. At the time of RBS, the mean BMI was 42.8 ± 7.9 kg/m2 for SADI and 43.4 ± 9.2 kg/m2 for OAGB. The follow-up examinations rates (%) after SADI were 97.6, 92.8, 90.5, 78.6, 57.1, and 100, 97.6, 95.2, 85.7, and 59.5 after OAGB. The BMI at the follow-up examinations were 39.1 ± 7.2, 34.2 ± 6.9, 31.2 ± 5.8, 30.2 ± 5.3, 29.3 ± 5.1 for SADI, and 39.5 ± 8.1, 36.6 ± 7.4, 34.7 ± 7.9, 32.9 ± 6.3, and 31.6 ± 5.9 for OAGB. The mean operating times for SADI and OAGB were 138 ± 40 and 123 ± 39 minutes, respectively. Three patients in the SADI group and 1 patient in the OAGB group developed a major complication within the first 30 postoperative days.ConclusionSADI and OAGB were effective second-step procedures for further weight reduction after LSG in initially super-obese patients after short to medium follow-up. There was a trend toward higher weight loss for SADI though this did not reach statistical significance. Substantial differences concerning surgery time and complications between the 2 procedures were not observed.  相似文献   
97.
目的探讨喉癌患者血小板表面血小板膜糖蛋白Ⅱb/Ⅲa纤维蛋白原受体(PAC-1)、血小板P-选择素(CD62P)阳性表达率以及与患者临床病理特征和复发的关系。方法选取2014年1月~2015年12月间在我院耳鼻喉科手术治疗的116例喉癌患者,随访≥2年,并选取同期在我院体检的健康人群60例为对照组,采用流式细胞仪检测法检测外周血PAC-1和CD62P阳性率,并分析与临床病理特征、复发的关系。结果喉癌患者PAC-1和CD62P阳性表达率分别为(17.82±1.76)%和(22.87±3.13)%,明显高于健康人群(P<0.05);而且在喉癌患者PAC-1表达和CD62P表达呈正相关性(r=0.238,P<0.05)。T3-T4分期或N2-N3分期患者PAC-1和CD62P阳性表达率高于T1-T2分期或N0-N1分期患者(P<0.05)。另外远处转移组PAC-1和CD62P阳性表达率高于未发生转移组(P<0.05);随访期间有24例患者复发,复发率为20.69%。复发喉癌患者PAC-1、CD62P阳性表达率分别为(17.02±0.85)%和(21.84±1.17)%,明显高于未复发的喉癌患者(P<0.05)。经Logistics回归分析,PAC-1和CD62P是喉癌患者复发的独立危险因素(P<0.05)。结论PAC-1和CD62P阳性表达率与喉癌患者T分期、淋巴结转移和远处转移密切相关,同时可作为喉癌局部复发、区域淋巴结转移、远处转移的预测指标。  相似文献   
98.
凌峰  屈志强  石健  罗密芳 《中国热带医学》2020,20(11):1062-1065
目的 分析总结南宁市江南区2019年登革热流行病学特征和疫情应急处置的工作情况,为今后有效地防制登革热提供对策、参考和技术支持。方法 收集南宁市江南区2019年登革热疫情相关数据,评价本次应急处置的工作成效。结果 2019年南宁市江南区登革热疫情严峻,共报告登革热病例370例,其中输入病例4例,本地病例366例;感染人数以家务待业和离退休者居多;男女性别比为1∶1.12;发病年龄最小1岁,最大92岁;发病的空间分布呈现高度聚集,福建园街道占本城区本地病例的87.70%。早期伊蚊应急监测布雷图指数和账诱指数合格率偏低,分别为72.17%和62.61%。针对本次疫情特性,制定有针对性的防控策略,做好精准疫情应急处置,有效压低峰值,迅速控制了疫情的扩散和蔓延。结论 本次疫情是由输入性病例导致本地病例社区水平暴发,疫情呈现多点暴发及扩散蔓延态势。需做好疫情研判、预警预测,准确分析流行病学特征,尽早实施登革热应急处置,精准防控、孳生地处理、健康宣教和病例管理是应急处置的关键措施。  相似文献   
99.
100.
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