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排序方式: 共有298条查询结果,搜索用时 15 毫秒
1.
《Vaccine》2022,40(6):904-911
BackgroundGSK initiated a Pregnancy Registry in the United States (US) for the reduced-antigen-content tetanus-diphtheria-acellular pertussis (Tdap; Boostrix, GSK) vaccine with the aim to detect and describe pregnancy outcomes in women vaccinated with Boostrix 28 days before estimated conception or during pregnancy.MethodsVoluntary reports of pregnancy exposure to Boostrix received from spontaneous and post-marketing surveillance sources in the US were assessed. Reports were classified as prospective or retrospective based on the knowledge of pregnancy outcomes at the time of reporting. For completeness, reports of exposure to Boostrix or to the Tdap-inactivated poliovirus vaccine (Boostrix-IPV, GSK) reported to the global safety database from countries outside the US were also evaluated.ResultsFrom May 2005 to August 2019, 1517 (1455 prospective and 62 retrospective) pregnancy reports were received in the Boostrix US Pregnancy Registry. Of the prospective reports, 250 had known outcomes: 244 live infants with no apparent birth defects (BDs), three live infants with BDs, and three spontaneous abortions with no apparent BDs. Of the retrospective reports, 55 had known outcomes: 33 live infants with no apparent BDs, 16 live infants with BDs, one spontaneous abortion with no apparent BDs, four stillbirths with no apparent BDs, and one stillbirth with BDs. Cumulatively, 1321 pregnancy reports (1006 for Boostrix; 315 for Boostrix-IPV) were received from countries outside the US. Of these, 163 prospective reports and 551 retrospective reports had known outcomes. Results were in line with those from the Boostrix US Pregnancy Registry.ConclusionsData currently available from the Boostrix US Pregnancy Registry and from countries outside the US suggested that exposure to Boostrix or Boostrix-IPV during pregnancy does not raise safety concerns related to adverse pregnancy outcomes or BDs. 相似文献
2.
《Mayo Clinic proceedings. Mayo Clinic》2022,97(7):1237-1246
ObjectiveTo determine the long-term cardiovascular disease risk of astronauts with spaceflight exposure compared with a well-matched cohort.MethodsNational Aeronautics and Space Administration (NASA) astronauts are selected into their profession based upon education, unique skills, and health and are exposed to cardiovascular disease risk factors during spaceflight. The Cooper Center Longitudinal Study (CCLS) is a generally healthy cohort from a preventive medicine clinic in Dallas, Texas. Using a matched cohort design, astronauts who were selected beginning April 1, 1959, (and each subsequent selection class through 2009) and exposed to spaceflight were matched to CCLS participants who met astronaut selection criteria; 1514 CCLS participants matched to 303 astronauts in a 5-to-1 ratio on sex, date of birth, and age. The outcome of cardiovascular mortality through December 31, 2016, was determined by death certificate or National Death Index.ResultsThere were 11 deaths caused by cardiovascular disease (CVD) among astronauts and 46 among CCLS participants. There was no evidence of increased mortality risk in astronauts (hazard ratio [HR]=1.10; 95% confidence interval [CI], 0.50 to 2.45) with adjustment for baseline cardiovascular covariates. However, the secondary outcome of CVD events showed an increased adjusted risk in astronauts (HR=2.41; 95% CI, 1.26 to 4.63).ConclusionNo increased risk of CVD mortality was observed in astronauts with spaceflight exposure compared with a well-matched cohort, but there was evidence of increased total CVD events. Given that the duration of spaceflight will increase, particularly on missions to Mars, continued surveillance and mitigation of CVD risk is needed to ensure the safety of those who venture into space. 相似文献
3.
目的预测托拉塞米在室温下的有效期。方法采用HPLC法测定主药含量,用经典恒温法预测其有效期。结果托拉塞米的降解反应属一级反应,在室温(25℃)条件下的分解速度常数K25℃=5.186 9×10-6,该注射液在25℃时的有效期t0.9=2.32年。结论自制的托拉塞米注射液的有效期暂定为2年。 相似文献
4.
5.
Rafat Zreiq Souad Kamel Sahbi Boubaker Asma A Al-Shammary Fahad D Algahtani Fares Alshammari 《AIMS Public Health》2020,7(4):828
COVID-19 pandemic is spreading around the world becoming thus a serious concern for health, economic and social systems worldwide. In such situation, predicting as accurately as possible the future dynamics of the virus is a challenging problem for scientists and decision-makers. In this paper, four phenomenological epidemic models as well as Suspected-Infected-Recovered (SIR) model are investigated for predicting the cumulative number of infected cases in Saudi Arabia in addition to the probable end-date of the outbreak. The prediction problem is formulated as an optimization framework and solved using a Particle Swarm Optimization (PSO) algorithm. The Generalized Richards Model (GRM) has been found to be the best one in achieving two objectives: first, fitting the collected data (covering 223 days between March 2nd and October 10, 2020) with the lowest mean absolute percentage error (MAPE = 3.2889%), the highest coefficient of determination (R2 = 0.9953) and the lowest root mean squared error (RMSE = 8827); and second, predicting a probable end date found to be around the end of December 2020 with a projected number of 378,299 at the end of the outbreak. The obtained results may help the decision-makers to take suitable decisions related to the pandemic mitigation and containment and provide clear understanding of the virus dynamics in Saudi Arabia. 相似文献
6.
目的:对中药保质期或有效期进行系统的调研,探讨中药饮片设定保质期或有效期的依据及其必要性,为提高中药饮片质量、保障临床用药安全提供技术支撑,为药品监管部门制定有关法规提供科学依据。方法:以国家知识基础设施数据库(CNKI)为数据来源,采用文献计量学研究方法,选用检索词为“中药材”并“有效期”“饮片”并“有效期”,“饮片”并“保质期”“中药材”并“保质期”“中药材”并“效期”和“饮片”并“效期”,利用CNKI平台工具以及Excel统计工具进行统计分析。结果:经数据库检索、筛选,获取中药材、饮片保质期或有效期或效期的相关有效文献共85篇,其中关于中药、饮片保质期的相关文献26篇,中药、饮片有效期或效期的相关文献59篇;在59篇关于中药有效期的文献中,74.58%的文献对于中药是否应该制定有效期、如何制定有效期等展开了讨论,25.42%的文献为中药有效期研究的实验性文献。结论:本文从中药材、饮片保质期与有效期的现状,质量评价指标,研究方法,饮片分类、保质期制定的必要性,及其存在的问题和建议等方面进行了梳理和归纳,为中药饮片保质期制定,提供了详实的文献依据。 相似文献
7.
Yingwei Qi MD MS Katie L. Allen Ziegler BS Shauna L. Hillman MS Mary W. Redman PhD Steven E. Schild MD David R. Gandara MD Alex A. Adjei MD PhD Sumithra J. Mandrekar PhD 《Cancer》2012,118(21):5358-5365
BACKGROUND:
In patients with advanced lung cancer, overall survival is largely influenced by progression status. Because progression‐free survival (PFS)‐based endpoints are controversial, the authors evaluated the impact of the progression date (PD) determination approach on PFS estimates.METHODS:
Individual patient data from 21 trials (14 North Central Cancer Treatment Group trials and 7 Southwest Oncology Group trials) were used. The reported PD (RPD) was defined as either the radiographic scan date or the clinical deterioration date. PD was determined using Method 1 (M1), the RPD; M2, 1 day after the last progression‐free scan; M3, midpoint between the last progression‐free scan and the RPD; and M4, an interval‐censoring approach. PFS was estimated using Kaplan‐Meier (M1‐M3), and maximum‐likelihood (M4) methods. Simulation studies were performed to understand the impact of the length of time elapsed between the last progression‐free scan and the PD on time‐to‐progression estimates.RESULTS:
PFS estimates using the RPD were the highest, and M2 was the most conservative. M3 and M4 were similar because the majority of progressions occurred during treatment (ie, frequent disease assessments). M3 was influenced less by the length of the assessment schedules (percentage difference from the true time‐to‐progression, <1.5%) compared with M1 (11% to 30%) and M2 (?8% to ?29%). The overall study conclusion was unaffected by the method used for randomized trials.CONCLUSIONS:
The magnitude of difference in the PFS estimates was large enough to alter trial conclusions in patients with advanced lung cancer. The results indicate that standards for PD determination, the use of sensitivity analyses, and randomized trials are critical when designing trials and reporting efficacy using PFS‐based endpoints. Cancer 2012. © 2012 American Cancer Society. 相似文献8.
Introduction
Tobacco quitlines (QLs) are efficacious and have assisted many smokers in achieving tobacco abstinence. However, most smokers are not able to achieve tobacco abstinence with QL services. QL counseling interventions for smokers who do not quit on their target quit date (TQD) and decline to set a new TQD after missing their TQD have not been systematically evaluated.Methods
A telephone survey of tobacco QLs in the United States (US) was conducted to examine systematic approaches used with smokers who do not quit on their TQD and decline to set a new TQD. Tobacco QLs service providers were identified through the North American Quitline Consortium (NAQC).Results
Fourteen service providers managing QLs of all 50 US states were identified and completed the voluntary survey. All providers recommended setting a new quit TQD if smokers did not achieve smoking cessation by their initial TQD. Six percent of US state QLs used brief motivational interviewing utilizing the “5R's” (relevance, risk, rewards, roadblocks, repetition). However, 90% of QLs had intervention protocols emphasizing smoking rate reduction.Conclusion
Although some US QLs utilized the “5Rs,” the majority provided smoking reduction interventions for smokers not achieving tobacco cessation by their initial TQD and declining to set a new TQD. Research is needed to evaluate the efficacy of smoking rate reduction methods implemented through QLs for increasing smoking abstinence rates. 相似文献9.
目的探讨脑梗死患者出生日期的五运六气分布特点。方法对3 222例脑梗死患者出生日期的天干、岁运、主气、客气等运气要素进行描述性统计分析,并通过卡方检验判断其间差异性。结果脑梗死患者出生时的天干、主气分布具有一定的差异性,且差异具有统计学意义(P0.05),其中出生在乙年(金运不及)者罹患率最高,己年(土运不及)者最低;出生在四之气(主气太阴湿土)者罹患率最高,终之气(主气太阳寒水)者最低。脑梗死患者出生时的岁运、客气分布差异没有统计学意义(P0.05)。结论出生时天干、主气的运气特征对后天脑梗死的罹患存在一定影响。 相似文献
10.
Francesco Vairo Emanuele Nicastri Salma Masauni Yussuf Angela Cannas Silvia Meschi Mwanakheir AA Mahmoud Azza H. Mohamed Paul Mohamed Maiko Pasquale De Nardo Nazario Bevilacqua Concetta Castilletti Antonino Di Caro Vincenzo Racalbuto Giuseppe Ippolito 《Emerging infectious diseases》2014,20(3):465-468
We conducted a seroprevalence survey among 500 healthy adult donors at Zanzibar National Blood Transfusion Services. Dengue virus IgG seroprevalence was 50.6% and independently associated with age and urban residence. These data will aid in building a surveillance, preparedness, and response plan for dengue virus infections in the Zanzibar Archipelago.Key words: dengue, seroprevalence, Zanzibar, viruses, vector-borne infections 相似文献