全文获取类型
收费全文 | 1288篇 |
免费 | 85篇 |
国内免费 | 1篇 |
专业分类
耳鼻咽喉 | 26篇 |
儿科学 | 72篇 |
妇产科学 | 47篇 |
基础医学 | 192篇 |
口腔科学 | 34篇 |
临床医学 | 85篇 |
内科学 | 270篇 |
皮肤病学 | 18篇 |
神经病学 | 51篇 |
特种医学 | 13篇 |
外科学 | 192篇 |
综合类 | 32篇 |
一般理论 | 2篇 |
预防医学 | 123篇 |
眼科学 | 16篇 |
药学 | 116篇 |
中国医学 | 5篇 |
肿瘤学 | 80篇 |
出版年
2023年 | 5篇 |
2022年 | 22篇 |
2021年 | 47篇 |
2020年 | 28篇 |
2019年 | 38篇 |
2018年 | 36篇 |
2017年 | 27篇 |
2016年 | 24篇 |
2015年 | 34篇 |
2014年 | 52篇 |
2013年 | 54篇 |
2012年 | 95篇 |
2011年 | 126篇 |
2010年 | 41篇 |
2009年 | 41篇 |
2008年 | 61篇 |
2007年 | 73篇 |
2006年 | 42篇 |
2005年 | 64篇 |
2004年 | 65篇 |
2003年 | 57篇 |
2002年 | 41篇 |
2001年 | 7篇 |
2000年 | 18篇 |
1999年 | 16篇 |
1998年 | 8篇 |
1997年 | 8篇 |
1996年 | 8篇 |
1995年 | 9篇 |
1994年 | 12篇 |
1993年 | 8篇 |
1992年 | 18篇 |
1991年 | 13篇 |
1990年 | 6篇 |
1989年 | 17篇 |
1988年 | 11篇 |
1987年 | 8篇 |
1986年 | 8篇 |
1985年 | 11篇 |
1984年 | 7篇 |
1983年 | 12篇 |
1982年 | 12篇 |
1981年 | 6篇 |
1980年 | 6篇 |
1975年 | 5篇 |
1974年 | 9篇 |
1973年 | 11篇 |
1970年 | 6篇 |
1967年 | 3篇 |
1966年 | 4篇 |
排序方式: 共有1374条查询结果,搜索用时 15 毫秒
21.
22.
Puri V Ranjit S Konda S Nicoloro SM Straubhaar J Chawla A Chouinard M Lin C Burkart A Corvera S Perugini RA Czech MP 《Proceedings of the National Academy of Sciences of the United States of America》2008,105(22):7833-7838
Storage of energy as triglyceride in large adipose-specific lipid droplets is a fundamental need in all mammals. Efficient sequestration of fat in adipocytes also prevents fatty acid overload in skeletal muscle and liver, which can impair insulin signaling. Here we report that the Cide domain-containing protein Cidea, previously thought to be a mitochondrial protein, colocalizes around lipid droplets with perilipin, a regulator of lipolysis. Cidea-GFP greatly enhances lipid droplet size when ectopically expressed in preadipocytes or COS cells. These results explain previous findings showing that depletion of Cidea with RNAi markedly elevates lipolysis in human adipocytes. Like perilipin, Cidea and the related lipid droplet protein Cidec/FSP27 are controlled by peroxisome proliferator-activated receptor gamma (PPARgamma). Treatment of lean or obese mice with the PPARgamma agonist rosiglitazone markedly up-regulates Cidea expression in white adipose tissue (WAT), increasing lipid deposition. Strikingly, in both omental and s.c. WAT from BMI-matched obese humans, expression of Cidea, Cidec/FSP27, and perilipin correlates positively with insulin sensitivity (HOMA-IR index). Thus, Cidea and other lipid droplet proteins define a novel, highly regulated pathway of triglyceride deposition in human WAT. The data support a model whereby failure of this pathway results in ectopic lipid accumulation, insulin resistance, and its associated comorbidities in humans. 相似文献
23.
Rao BL Yeolekar LR Kadam SS Pawar MS Kulkarni PB More BA Khude MR 《The Southeast Asian journal of tropical medicine and public health》2005,36(4):906-909
Influenza surveillance was conducted in Pune, India in 2003. A total of 573 throat swabs/ nasal swabs (TS/NS) and 190 nasopharyngeal aspirates (NPA) were collected from 763 in- and out-patients who were mostly children aged 0-16 years. TS/NS (507/573) and NPA (42/190) specimens were processed in MDCK cell cultures and identified with the hemagglutination inhibition test (HI). A total of 37 influenza viruses was isolated: twenty-three type A (H3N2) and 14 type B of the Yamagata lineage were isolated from 29 children and 8 adults. Three type A (H3N2) isolates were characterized as being similar to A/Panama/2007/99 like, A/Korea/770/2000 like, and B/Sichuan/379/99 like strains. 相似文献
24.
Sripad V. Khairnar Ranjit Kumar Nath Balram Yadav Kakasaheb Bhosale Sulabh Chandraker 《Indian heart journal》2021,73(1):44-48
ObjectiveThe study aimed at to find out prevalence of abnormal upper limb arterial anatomy and its correlation with access failure during transradial coronary angiography.MethodThis was a prospective observational study of 1512 patients who had undergone transradial coronary angiography (CAG). Angiographic assessment of upper limb arterial tree was performed when the angiographic guidewire or the diagnostic catheter followed an abnormal path or got stuck in its course.ResultsAbout 5.29% patients (80/1512) were noted to have abnormal upper limb arterial anatomy. The most common abnormality detected were radio-ulnar loop in 22 (1.46%) patients, tortuous upper limb arteries 19 (1.25%) and abnormal high origin of radial artery 10 (0.66%) patients. Access failure was encountered in 4.4% (67/1512) of total patients and 64.17% (43/67) access failure was due to abnormal upper limb arterial anatomy.ConclusionAbnormal upper limb arterial anatomy was the most common cause of access failure in transradial coronary angiography in this study. 相似文献
25.
Jae-Jin Cho Brigid Joseph Baljit Singh Sappal Ranjit K Giri Richard Wang John W Ludlow Mark E Furth Robert Susick Sanjeev Gupta 《Liver international》2004,24(4):361-370
BACKGROUND: The availability of well-characterized human liver cell populations that can be frozen and thawed will be critical for cell therapy. We addressed whether human hepatocytes can recover after cryopreservation and engraft in immunodeficient mice. METHODS: We isolated cells from discarded human livers and studied the properties of cryopreserved cells. The viability of thawed cells was established with multiple in vitro assays, including analysis of liver gene expression, ureagenesis, cytochrome P450 activity, and growth factor-induced cell proliferation. The fate of transplanted cells was analysed in immunodeficient NOD-SCID mice. RESULTS: After thawing, the viability of human hepatocytes exceeded 60%. Cells attached to culture dishes, proliferated following growth factor stimulation and exhibited liver-specific functions. After transplantation in NOD-SCID mice, cells engrafted in the peritoneal cavity, a heterologous site, as well as the liver itself, retained hepatic function and proliferated in response to liver injury. Transplanted hepatocytes were integrated in the liver parenchyma. Occasionally, transplanted cells were integrated in bile ducts. CONCLUSIONS: Cryopreserved human liver cell showed the ability to retain functional integrity and to reconstitute both hepatic and biliary lineages in mice. These studies offer suitable paradigms aimed at characterizing liver cells prior to transplantation in people. 相似文献
26.
Nalini Ranjit Anna V Wilkinson Leslie M Lytle Alexandra E Evans Debra Saxton Deanna M Hoelscher 《The international journal of behavioral nutrition and physical activity》2015,12(Z1):S4
Background
It is well documented in the literature that low socioeconomic status (SES) is associated with lower consumption of healthy foods and that these differences in consumption patterns are influenced by neighborhood food environments. Less understood is the role that SES differences in physical and social aspects of the home food environment play in consumption patterns.Methods
Using data on 4th grade children from the 2009–2011 Texas School Physical Activity and Nutrition (SPAN) study, we used mixed-effects regression models to test the magnitude of differences in the SPAN Health Eating Index (SHEI) by parental education as an indicator of SES, and the extent to which adjusting for measures of the home food environment, and measures of the neighborhood environment accounted for these SES differences.Results
Small but significant differences in children’s SHEI by SES strata exist (-1.33 between highest and lowest SES categories, p<0.01). However, incorporating home food environment and neighborhood environment measures in this model eliminates these differences (-0.7, p=0.145). Home food environment explains a greater portion of the difference. Both social (mealtime structure) and physical aspects (food availability) of the home food environment are strongly associated with consumption of healthy and unhealthy foods.Conclusions
Our findings suggest that modifiable parent behaviors at home can improve children’s eating habits and that the neighborhood may impact diet in ways other than through access to healthy food.27.
Rao SS Mudipalli RS Mujica VR Patel RS Zimmerman B 《The American journal of gastroenterology》2003,98(8):1688-1695
OBJECTIVES: The effects of gender and age on human esophageal function is poorly defined. Our aim was to investigate the sensory perception and the biomechanical properties of the esophagus both at the smooth muscle and the striated muscle segments in age- and gender-matched healthy subjects. Eleven older individuals (five men and six women, aged 55-82 yr) and 11 younger healthy individuals (five male and six female, aged 22-45 yr) participated in this study. METHODS: Graded balloon distentions were performed at the striated muscle and the smooth muscle segments of the esophagus in a random order using impedance planimetry. Impedance planimetry facilitated simultaneous assessments of the biomechanical properties and sensory perception. RESULTS: We found that both at the striated and smooth muscle segments, the cross-sectional area, circumferential wall tension-strain relationship and the sensory thresholds were similar between men and women. In contrast, at both of these segments, the cross-sectional area was larger (p < 0.05), the circumferential wall tension-strain association had shifted significantly (p < 0.05) to the left (i.e., the wall was stiffer), and the median thresholds for discomfort and pain were higher (p < 0.05) in older subjects. The biomechanical properties and thresholds for sensory perception also varied between the two esophageal segments. CONCLUSIONS: Aging was associated with a larger lumen and a stiffer but less sensitive esophageal wall. Thus, aging but not gender may influence esophageal function. 相似文献
28.
尼古丁对人树突状细胞的激活及其与急性冠状动脉综合征的关系 总被引:2,自引:0,他引:2
目的:研究尼古丁对人树突状细胞(DC)功能的影响及其与急性冠状动脉综合征(ACS)发病的关系.方法:观察体外尼古丁对DC功能的作用以及11例正常对照者(正常对照组)与45例ACS者(ACS组)发病时及戒烟后DC的功能状态.流式细胞仪检测DC CD86的表达;混合淋巴反应检测DC对T淋巴细胞的刺激作用;酶联免疫吸附法(ELISA)测定混合淋巴反应上清液中细胞因子水平.结果:与正常对照组比较,ACS时DC表面CD86的表达明显增高,对T淋巴细胞刺激的能力增强;致炎细胞因子分泌增多;DC CD86的表达与日吸烟量正相关(r=0.63,P<0.01);平均戒烟5个月后,DC功能接近正常;体外尼古丁亦能明显刺激DC的功能,呈浓度依赖性.结论:①ACS时DC明显激活;②戒烟后DC功能可迅速恢复;③尼古丁可能是ACS时DC激活的刺激因素之一. 相似文献
29.
Upasana Sahu Prakash K. Sahoo Shantanu K. Kar Biranchi N. Mohapatra Manoranjan Ranjit 《Human immunology》2013
Microparticles (MPs) resulting from vesiculation of different cell types in Plasmodium falciparum infection correlate with the level of proinflammatory cytokine TNF that may thereby determine the disease severity. Using TruCount tube based flow cytometric method for the exact quantification of MP and enzyme linked immunosorbent assay for the measurement of TNF, we conducted a hospital based case control study on P. falciparum malaria patients to scrutinize and infer the link between the two. In 52 cerebral malaria (CM), 21 multi-organ-dysfunction (MOD), 12 non cerebral severe malaria (NCSM) and 43 uncomplicated malaria patients, the MP level was found to be significantly elevated in febrile malaria patients compared to healthy controls and a striking decrease in MP level was observed with the clearance of the P. falciparum infection in the patients upon follow-up. The lowering of the parasite density with the level of plasma TNF and the positive correlation of the cytokine with the cell derived MPs and negative correlation with the respective cell count in human malaria patients suggests that TNF may be a key stimulant to the cells resulting in the release of MPs in malaria infection. 相似文献
30.
Rajib Kundu Shantanu Nandy Arunabha Tapadar Ranjit Kumar Ghosh Aniruddha Sarkar Sukanya Palit 《Journal of the Anatomical Society of India》2013,62(1):62-67
Aim: Localization of isolated clusters of anterior olfactory nucleus (AON) in a human olfactory bulb and tract. Materials and methods: This investigation was done on human olfactory bulbs and their tracts, collected from the freshly donated cadavers, before embalming, in the Department of Anatomy, IPGMER, Kolkata. H&E stained histological slides were prepared along the whole length of specimens and examined under a Leica DM 2000 microscope and with a Leica Quin image analyzer. Results: The anterior olfactory nucleus was detected in the form of a major cluster and in two smaller clusters of neurons. The major cluster was located at the caudal pole of the bulb and was composed of medium-sized triangular cells which had an average diameter of 13.92 ± 3.43 μm. Out of the two minor clusters, one was detected at the beginning and another at the middle of the olfactory tract. Here neurons were little larger in size and their diameter ranged approximately 15–17 μm. Olfactory striae also accommodated some neurons in a scattered manner. Conclusion: This observation will be helpful in exploration of the complex role of AON in the organization and function of the olfactory system and its clinical significance in human. 相似文献