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   461篇
  免费   22篇
  国内免费   2篇
耳鼻咽喉   20篇
儿科学   10篇
妇产科学   15篇
基础医学   56篇
口腔科学   24篇
临床医学   41篇
内科学   103篇
皮肤病学   4篇
神经病学   56篇
特种医学   27篇
外科学   32篇
综合类   10篇
预防医学   33篇
眼科学   4篇
药学   14篇
中国医学   4篇
肿瘤学   32篇
  2023年   5篇
  2022年   11篇
  2021年   17篇
  2020年   17篇
  2019年   12篇
  2018年   7篇
  2017年   7篇
  2016年   13篇
  2015年   9篇
  2014年   13篇
  2013年   21篇
  2012年   40篇
  2011年   30篇
  2010年   23篇
  2009年   15篇
  2008年   14篇
  2007年   24篇
  2006年   34篇
  2005年   27篇
  2004年   23篇
  2003年   30篇
  2002年   20篇
  2001年   6篇
  2000年   5篇
  1999年   6篇
  1997年   2篇
  1996年   1篇
  1995年   3篇
  1994年   1篇
  1993年   2篇
  1992年   3篇
  1991年   3篇
  1989年   3篇
  1988年   5篇
  1987年   6篇
  1986年   1篇
  1985年   4篇
  1984年   3篇
  1983年   1篇
  1982年   2篇
  1981年   1篇
  1979年   2篇
  1978年   1篇
  1974年   1篇
  1972年   2篇
  1971年   2篇
  1970年   1篇
  1968年   2篇
  1967年   2篇
  1963年   1篇
排序方式: 共有485条查询结果,搜索用时 15 毫秒
1.
2.
3.
PURPOSE: We conducted a cross-sectional study examining potentially modifiable factors associated with cognitive impairments (mild or severe) in older whites, African Americans and Hispanics attending an outpatient eye clinic. METHODS: In-clinic interviews and physical examinations assessed social, demographic and health information from 100 consecutive Hispanic, African-American and white adults aged > or = 55. Our primary outcome was presence of any cognitive impairment (mild or severe) using the St. Louis University Mental Status Examination (SLUMS) scale. RESULTS: Of the 100 subjects, 65 screened positive for cognitive impairments on the SLUMS cognitive instrument: 46 with mild cognitive impairment and 19 with severe impairment (possible dementia). African-American and Hispanic adults (nonwhites) were significantly more likely to have cognitive impairment compared to white adults (OR 2.80: 95% CI = 1.05-7.44), independent of age, years of education and systolic blood pressure. Subjects with diabetes also had increased odds of cognitive impairments (OR 3.28, 95% CI = 1.21-8.90) even after adjusting for relevant confounders. There was a nonsignificant trend between visual acuity impairment and cognitive impairment (p = 0.059). CONCLUSIONS: Sixty-five percent of adults aged > or = 55 attending the eye clinic screened positive for cognitive impairments, with higher rates among nonwhites and adults living with diabetes.  相似文献   
4.
PURPOSE: Docetaxel, a taxane previously approved for the treatment of breast cancer and non-small cell lung cancer, was approved by the United States Food and Drug Administration on May 19, 2004 for use in combination with prednisone for the treatment of metastatic androgen-independent (hormone-refractory) prostate cancer. The purpose of this summary is to review the database supporting this approval. EXPERIMENTAL DESIGN: In a randomized, global study enrolling 1,006 patients, two schedules of docetaxel were compared with mitoxantrone + prednisone as follows: MTZ q 3w, mitoxantrone 12 mg/m2 every 21 days + prednisone 5 mg twice a day for a total of 10 cycles; TXT q 3w, docetaxel 75 mg/m2 every 21 days + prednisone 5 mg twice a day for a total of 10 cycles; and TXT qw, docetaxel 30 mg/m2 days 1, 8, 15, 22, and 29 every 6 weeks + prednisone 5 mg twice a day for a total of 5 cycles. RESULTS: There was a statistically significant overall survival advantage shown for the TXT q 3w arm over MTZ q 3w (median survival 18.9 months versus 16.5 months, P = 0.0094). No overall survival advantage was shown for TXT qw compared with MTZ q 3w. The most commonly occurring adverse events included anemia, neutropenia, infection, nausea, sensory neuropathy, fluid retention, alopecia, nail changes, diarrhea, and fatigue. CONCLUSIONS: This report describes the Food and Drug Administration review supporting this first approval of a combination therapy for hormone-refractory prostate cancer based on demonstration of a survival benefit.  相似文献   
5.
Purpose:This study aimed to evaluate the effect of using the lubricated eyelid speculum on the overall pain perception by the subject patients who underwent cataract surgery by phacoemulsification technique under topical anesthesia.Methods:A prospective interventional randomized comparative study was conducted at the tertiary eye care center, wherein adult patients scheduled for bilateral cataract surgery with phacoemulsification techniques under topical anesthesia were randomized to undergo surgery with two different modes of eyelid speculum insertion, either with or without lubrication of the eyelid speculum. Fifty percent of the patients underwent surgery with eyelid speculum without lubrication, and 50% with lubrication of the eyelid speculum. The primary outcome was to compare the level of overall pain perception among the subject patients of the two groups by using the Visual Analogue Scale (VAS) in the immediate postoperative period.Results:The study included 130 patients who underwent bilateral cataract surgery (n = 260 eyes) under topical anesthesia, wherein n = 130 eyes underwent surgery using lubricated eyelid speculum and n = 130 eyes underwent surgery with dry eyelid speculum. Pain perception score assessed on the VAS (0–10 cm) ranged from 0.5 to 6, with a mean ± standard deviation of 2.06 ± 1.12. A significant correlation was found with two different methods of eyelid speculum insertion with reduced overall pain perception in patients with the use of lubricated eyelid speculum compared to the dry eyelid speculum (P = 0.0001).Conclusion:The overall pain perception associated with cataract surgery performed by phacoemulsification technique under topical anesthesia can be further minimized by lubricating the eyelid speculum prior to insertion for exposing the globe.  相似文献   
6.
ObjectiveTo assess the occurrence of Leptospira spp serovar Hardjo among Zebu cattle in some livestock producing areas of Kaduna State, Nigeria.MethodsSera samples were obtained from 164 Zebu breed of cattle above one year osf age in seven cattle farms were screened for antibodies to Leptospira spp. serovar Hardjo using Enzyme linked immunosorbent assay (ELISA).ResultsAntibodies to Leptospira spp. serovar Hardjo were detected in eighteen (10.98%) out of the 164 animals sampled. There was no significant difference (P>0.05) in seropositivity between the different age groups or between different Zebu breeds.ConclusionThe presence of Leptospirosis among the Zebu breeds of cattle may poses a threat to livestock production and has public health implication due to its zoonotic potential.  相似文献   
7.
Jonjev ZS  Rajić J  Majin M  Donat D 《Herz》2012,37(6):709-712
Intracardiac metastases of germ cell testicular tumors are not commonly seen in clinical practice. The clinical presentation of right-sided heart metastases ranges widely. Depending upon its size and intracardiac location, it could be highly symptomatic, leading to a congestive heart failure, pulmonary embolism, and death, or completely asymptomatic. Improved imaging techniques and treatment strategies demonstrate that right-sided heart metastasis should be considered a potentially dangerous but treatable disease. Presented is the case of a 24-year-old man with a testicular nonseminomatous germ cell tumor, which after metastasizing in the right atrium differentiated into a teratoma and resulted in an inflow obstruction of the right ventricle.  相似文献   
8.
This paper investigated the degradation of the pharmaceutical drug Valsartan (VS) using non-equilibrium atmospheric pressure plasma (NEAPP) with various operating conditions. The heterogeneous photocatalyst ZnO nanoparticles (NP''s) were synthesized using a hydrothermal process. The morphology, chemical composition and structure of as-synthesized ZnO NPs were examined by Field Emission Scanning Electron Microscopy (FE-SEM), Fourier Transform Infrared Spectroscopy (FTIR) and X-ray diffraction (XRD) analysis. Then, VS degradation was examined in three subsequent treatment conditions including plasma treatment alone, the combination of plasma with as-prepared ZnO NPs and various environments (air, oxygen and hydrogen peroxide) at fixed plasma operating potential and treatment time. The degradation efficiency of plasma-treated VS by various conditions was observed using UV-visible spectroscopy. Optical Emission Spectrometry (OES) was used to characterize the distribution and emission intensity of various reactive species (OH˙, N2-SPS and O) during the degradation processes which plays a vital role in the degradation of VS. The role of OH˙ and H2O2 during the degradation process was further examined by chemical dosimetry and spectroscopic techniques. Furthermore, pH, conductivity and TOC of the untreated and plasma-treated VS were also investigated. The results on the degradation of VS showed that plasma treatment combined with ZnO NP''s has a significant effect on degradation of molecules of VS than degradation processes carried out by other experimental conditions due to the formation of higher concentrations of various reactive oxygen and nitrogen species during the degradation processes.

Degradation of valsartan by plasma combined with various environmental conditions.  相似文献   
9.
10.
Recent data suggest that oxidative injury may play an important role in demyelination and neurodegeneration in multiple sclerosis (MS). We compared the extent of oxidative injury in MS lesions with that in experimental models driven by different inflammatory mechanisms. It was only in a model of coronavirus-induced demyelinating encephalomyelitis that we detected an accumulation of oxidised phospholipids, which was comparable in extent to that in MS. In both, MS and coronavirus-induced encephalomyelitis, this was associated with massive microglial and macrophage activation, accompanied by the expression of the NADPH oxidase subunit p22phox but only sparse expression of inducible nitric oxide synthase (iNOS). Acute and chronic CD4+ T cell-mediated experimental autoimmune encephalomyelitis lesions showed transient expression of p22phox and iNOS associated with inflammation. Macrophages in chronic lesions of antibody-mediated demyelinating encephalomyelitis showed lysosomal activity but very little p22phox or iNOS expressions. Active inflammatory demyelinating lesions induced by CD8+ T cells or by innate immunity showed macrophage and microglial activation together with the expression of p22phox, but low or absent iNOS reactivity. We corroborated the differences between acute CD4+ T cell-mediated experimental autoimmune encephalomyelitis and acute MS lesions via gene expression studies. Furthermore, age-dependent iron accumulation and lesion-associated iron liberation, as occurring in the human brain, were only minor in rodent brains. Our study shows that oxidative injury and its triggering mechanisms diverge in different models of rodent central nervous system inflammation. The amplification of oxidative injury, which has been suggested in MS, is only reflected to a limited degree in the studied rodent models.  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