全文获取类型
收费全文 | 474篇 |
免费 | 27篇 |
国内免费 | 3篇 |
专业分类
耳鼻咽喉 | 1篇 |
儿科学 | 40篇 |
妇产科学 | 25篇 |
基础医学 | 48篇 |
口腔科学 | 26篇 |
临床医学 | 34篇 |
内科学 | 121篇 |
皮肤病学 | 12篇 |
神经病学 | 34篇 |
特种医学 | 4篇 |
外科学 | 62篇 |
综合类 | 6篇 |
预防医学 | 27篇 |
眼科学 | 18篇 |
药学 | 27篇 |
中国医学 | 3篇 |
肿瘤学 | 16篇 |
出版年
2023年 | 3篇 |
2022年 | 4篇 |
2021年 | 12篇 |
2020年 | 7篇 |
2019年 | 15篇 |
2018年 | 23篇 |
2017年 | 5篇 |
2016年 | 15篇 |
2015年 | 12篇 |
2014年 | 22篇 |
2013年 | 34篇 |
2012年 | 36篇 |
2011年 | 49篇 |
2010年 | 26篇 |
2009年 | 19篇 |
2008年 | 52篇 |
2007年 | 41篇 |
2006年 | 30篇 |
2005年 | 21篇 |
2004年 | 28篇 |
2003年 | 22篇 |
2002年 | 13篇 |
2001年 | 2篇 |
2000年 | 1篇 |
1999年 | 2篇 |
1997年 | 1篇 |
1996年 | 1篇 |
1995年 | 2篇 |
1994年 | 1篇 |
1993年 | 2篇 |
1990年 | 1篇 |
1989年 | 1篇 |
1981年 | 1篇 |
排序方式: 共有504条查询结果,搜索用时 20 毫秒
1.
In vitro studies with recombinant Plasmodium falciparum apical membrane antigen 1 (AMA1): production and activity of an AMA1 vaccine and generation of a multiallelic response 总被引:5,自引:0,他引:5 下载免费PDF全文
Kennedy MC Wang J Zhang Y Miles AP Chitsaz F Saul A Long CA Miller LH Stowers AW 《Infection and immunity》2002,70(12):6948-6960
Apical membrane antigen 1 (AMA1) is regarded as a leading malaria blood-stage vaccine candidate. While the overall structure of AMA1 is conserved in Plasmodium spp., numerous AMA1 allelic variants of P. falciparum have been described. The effect of AMA1 allelic diversity on the ability of a recombinant AMA1 vaccine to protect against human infection by different P. falciparum strains is unknown. We characterize two allelic forms of AMA1 that were both produced in Pichia pastoris at a sufficient economy of scale to be usable for clinical vaccine studies. Both proteins were used to immunize rabbits, singly and in combination, in order to evaluate their immunogenicity and the ability of elicited antibodies to block the growth of different P. falciparum clones. Both antigens, when used alone, elicited high homologous anti-AMA1 titers, with reduced strain cross-reactivity. Similarly, sera from rabbits immunized with a single antigen were capable of blocking the growth of homologous parasite strains at levels theoretically sufficient to clear parasite infections. However, heterologous inhibition was significantly reduced, providing experimental evidence that AMA1 allelic diversity is a result of immune pressure. Encouragingly, rabbits immunized with a combination of both antigens exhibited titers and levels of parasite inhibition as good as those of the single-antigen-immunized rabbits for each of the homologous parasite lines, and consequently exhibited a broadening of allelic diversity coverage. 相似文献
2.
Farideh Nejat Parvin Tajik Mostafa El Khashab Syed Shuja Kazmi Ghamar Taj Khotaei Shahrzad Salahesh 《Journal of microbiology, immunology, and infection》2008,41(2):112-117
BACKGROUND AND PURPOSE: Shunt infection represents a particularly morbid condition, which can also result in mortality. In order to decrease the high morbidity and mortality rates, prevention is an essential step. The purpose of this study was to compare the prophylactic use of ceftriaxone and trimethoprim-sulfamethoxazole (SXT) for the prevention of ventriculoperitoneal (VP) shunt infection. METHODS: In this prospective, single-institution, randomized clinical trial, 107 children with hydrocephalus and an indication for shunting were randomly assigned to prophylaxis with ceftriaxone (n = 50) or SXT (55), each administered as a single dose during anesthesia and two divided doses postoperatively. Patients were followed up for at least one year. RESULTS: The mean age of patients was 15 months, and 85% were aged 6 months or younger. During the first postoperative year, meningitis occurred in 13.5% of patients receiving ceftriaxone and 14.5% of the SXT group, with no statistically significant difference between the groups. Younger age, presence of cerebrospinal fluid leakage and aqueductal stenosis as a cause of hydrocephalus showed significant correlation with meningitis occurrence on univariate analysis. However, only the latter 2 factors were associated with meningitis on multivariate analysis. The risk of shunt infection did not correlate with the gender of the patient, time of VP shunt surgery, or duration of hospitalization for shunting. CONCLUSION: Ceftriaxone and SXT showed similar efficacy in preventing shunt infection. Cerebrospinal fluid leakage before or after VP shunt placement and aqueductal stenosis were independent risk factors for meningitis after VP shunt. 相似文献
3.
Bischoff FZ Sinacori MK Dang DD Marquez-Do D Horne C Lewis DE Simpson JL 《Human reproduction update》2002,8(6):493-500
Both intact fetal cells as well as cell-free fetal DNA are present in the maternal circulation and can be recovered for non-invasive prenatal genetic diagnosis. Although methods for enrichment and isolation of rare intact fetal cells have been challenging, diagnosis of fetal chromosomal aneuploidy including trisomy 21 in first- and second-trimester pregnancies has been achieved with a 50-75% detection rate. Similarly, cell-free fetal DNA can be reliably recovered from maternal plasma and assessed by quantitative PCR to detect fetal trisomy 21 and paternally derived single gene mutations. Real-time PCR assays are robust in detecting low-level fetal DNA concentrations, with sensitivity of approximately 95-100% and specificity near 100%. Comparing intact fetal cell versus cell-free fetal DNA methods for non-invasive prenatal screening for fetal chromosomal aneuploidy reveals that the latter is at least four times more sensitive. These preliminary results do not support a relationship between frequency of intact fetal cells and concentration of cell-free fetal DNA. The above results imply that the concentration of fetal DNA in maternal plasma may not be dependent on circulating intact fetal cells but rather be a product of growth and cellular turnover during embryonic or fetal development. 相似文献
4.
Farideh Doroodgar Feizollah Niazi Sana Niazi Azad Sanginabadi Cyrus Alinia 《国际眼科杂志》2019,19(7):1089-1094
目的:评估可植入式Phakic角膜接触镜治疗稳定型圆锥角膜患者的疗效、安全性、稳定性和可预测性。
方法:共14例患者采用植入式Phakic角膜接触镜(IPCL)矫正屈光不正,测量了未矫正视力、最佳矫正视力、离焦曲线、对比敏感度、屈光度及可能的副作用。评估结果超过6mo。
结果:平均等效球镜度(SE)和散光在术后6mo末次检查时由术前-6.94±2.79 DS和-4.24±1.42 DC分别变为术后-0.23±0.43 DS和-1.05±0.49 DC。术前平均Snellen视力为0.18±0.10。6mo内未矫正视力和最佳矫正视力平均值分别为0.13±0.10和0.05±0.15。平均安全指数为1.11。所有眼视力均无降低,其中22眼视力提高超过1行。20眼(71.4%)屈光度在0.50 D以内,27眼(96.42%)在±1.00 D以内。术后1wk至6mo,屈光度变化为-0.23±0.43(范围: -1.00至+0.75)。6mo内角膜内皮细胞(ECL)丢失率小于5%。术后6mo眼压(IOP)为11.32±2.28 mmHg。
结论:Toric植入式Phakic角膜接触镜在矫正与稳定圆锥角膜相关的近视和近视散光方面具有有效性、安全性和可预测性。 相似文献
5.
6.
Javad VATANI Farideh GOLBABAEI Somayeh Farhang DEHGHAN Azam YOUSEFI 《Industrial health》2016,54(1):14-19
The present study aimed to investigate the applicability of Universal Thermal
Climate Index (UTCI) as an innovative and science-based index in public health researches,
in occupational heat stress assessment. All indoor and outdoor workers (200 people) of
Brick industries of Shahroud, Iran participated in the research. First, the environmental
variables such as air temperature, wet-bulb temperature, globe temperature, air velocity
and relative humidity were measured; then UTCI and WBGT (wet-bulb globe temperature)
indices were calculated. Simultaneously, physiological parameters including systolic and
diastolic blood pressure, oral temperature, skin temperature, tympanic temperature and
heart rate of workers were measured. UTCI and WBGT indices were 34.2 ± 2°C, 21.8 ± 1.8°C
in the outdoor environments and 38.1 ± 4.4°C, 24.7 ± 3.3°C at the indoor environments,
respectively. There were the weak inverse relationships between UTCI and WBGT indices at
the outdoor environments and physiological responses such as systolic blood pressure, and
diastolic blood pressure. However, there were no similar results for indoor environments.
The significant relationships were found between UTCI and WBGT at both indoor and outdoor
environments. Both UTCI and WBGT indices are suitable for assessing the occupational heat
stress. Although, UTCI index seems more appropriate for heat stress assessment in the
environments with low humidity and air velocity. 相似文献
7.
8.
Analysis of IN.PACT DEEP trial on the association between changes in perfusion from pre‐ to postrevascularization and clinical outcomes in critical limb ischemia 下载免费PDF全文
9.
10.
Maryam Abbasian Mehri Delvarianzadeh Hossein Ebrahimi Farideh Khosravi Pirasteh Nourozi 《Diabetes & Metabolic Syndrome: Clinical Research & Reviews》2018,12(4):497-500