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   185篇
  免费   5篇
  国内免费   1篇
儿科学   7篇
妇产科学   2篇
基础医学   12篇
口腔科学   6篇
临床医学   11篇
内科学   79篇
皮肤病学   1篇
神经病学   1篇
特种医学   42篇
外科学   5篇
综合类   2篇
预防医学   2篇
药学   15篇
肿瘤学   6篇
  2023年   2篇
  2020年   2篇
  2017年   1篇
  2015年   2篇
  2014年   3篇
  2013年   4篇
  2010年   1篇
  2009年   7篇
  2008年   1篇
  2007年   3篇
  2006年   1篇
  2004年   2篇
  2002年   2篇
  2000年   2篇
  1998年   15篇
  1997年   10篇
  1996年   7篇
  1995年   10篇
  1994年   14篇
  1993年   19篇
  1992年   1篇
  1989年   6篇
  1988年   14篇
  1987年   10篇
  1986年   5篇
  1985年   6篇
  1984年   2篇
  1983年   4篇
  1982年   6篇
  1981年   3篇
  1980年   2篇
  1979年   1篇
  1978年   2篇
  1976年   3篇
  1975年   1篇
  1964年   1篇
  1963年   3篇
  1959年   4篇
  1958年   5篇
  1957年   2篇
  1955年   1篇
  1948年   1篇
排序方式: 共有191条查询结果,搜索用时 15 毫秒
31.
32.
33.
34.

Objectives

The aim of this work was to audit the extent to which routine HIV care in the UK conforms with British HIV Association (BHIVA) guidelines and specifically the proportion of patients starting highly active antiretroviral therapy (HAART) who achieve the outcome of virological suppression below 50 HIV‐1 RNA copies/mL within 6 months.

Methods

A prospective cohort review of adults with HIV infection who started antiretroviral therapy (ART) for the first time between April and September 2006 was carried out using structured questionnaire forms.

Results

A total of 1170 adults from 122 clinical sites participated in the review. Of these patients, 699 (59.7%) started ART at CD4 counts <200 cells/μL and 193 (16.5%) had not been tested for HIV drug resistance. Excluding patients with valid reasons for stopping short‐term ART, 795 (73.5%) of 1081 patients had an undetectable viral load (VL) at follow‐up. Detectable VL was strongly associated with pretreatment CD4 count below 50 cells/μL and pretreatment VL above 100 000 copies/mL, and was not associated with clinic location or case load. About a quarter of patients did not have a VL measurement during the first 6 weeks after starting ART.

Conclusions

The majority of patients who initiated ART at sites participating in this UK national audit were managed within the BHIVA guidelines and achieved virological suppression below 50 copies/mL around 6 months after commencing treatment. Poor VL outcomes were associated with very low CD4 cell count and/or high VL at baseline but not with clinic case load or location. There is an urgent need to diagnose patients at an earlier stage of their HIV disease.  相似文献   
35.
36.
37.
Chronically anemic baboons on a continuous hydroxyurea regimen were treated with pulsed doses of recombinant human erythropoietin (rHuEpo) to test whether the combination of these two compounds, which individually induce F-cell production, can enhance further F-cell output. A low-F-cell-responding animal under chronic hydroxyurea treatment was given three separate pulses of Epo and responded with F- reticulocyte increments that were similar to the sum increments caused by either hydroxyurea alone or rHuEpo alone. The same results were obtained in a high-F-responding animal similarly treated. These findings suggest that rHuEpo and hydroxyurea can increase F cell numbers in an additive fashion. It is speculated that both compounds act through perturbation of erythroid differentiation kinetics.  相似文献   
38.
It has been proposed that extremely low frequency (ELF) magnetic fields may enhance tumorigenesis through a co-promotional mechanism. This hypothesis has been further tested using the two-stage model of mouse skin carcinogenesis, i.e. 12-O-tetradecanoylphorbol-13-acetate (TPA)- induced promotion of skin tumors in mice initiated by a single subcarcinogenic dose of 7,12-dimethylbenz[a]anthracene. Experimentation described herein utilized the SENCAR mouse and examined the effect of a magnetic field on skin tumor promotion induced by three different doses of TPA within its dose-response range, i.e. 0.85, 1.70 or 3.40 nmol, administered twice per week. SENCAR mice (56/treatment group) were exposed to a 60 Hz magnetic field having a flux density of 2 mT for 6 h/day for 5 days/week and compared with mice exposed to the ambient magnetic field. Tumor incidence and multiplicity were monitored weekly for 23 weeks of TPA promotion. Statistical evaluation of the effects of the magnetic field on tumor incidence and multiplicity did not reveal any statistically significant effects; thus, within the sensitivity limits imposed by the animal model and the exposure parameters employed, no promotional or co-promotional effect of a 2 mT magnetic field on skin tumor development in SENCAR mice could be demonstrated.   相似文献   
39.
Increased colonic wall thickness has been reported in patients exposed to large doses of high strength pancreatic enzyme preparations who did not develop fibrosing colonopathy. This has been interpreted as evidence for a spectrum of subclinical disease. The relation between sonographically measured colonic wall thickness and pancreatic enzyme preparation and dose was studied in 86 children with cystic fibrosis (CF). Colonic wall thickness of a control group was also measured. The average thickness in all colonic regions was higher in the CF group (overall average range 0.7-2.5 mm v 0.6-1.4 mm in the control group). There was no significant relation between colonic wall thickness and age, sex, total dose of lipase, or copolymer. Apart from one patient with an early colonic stricture, none of those exposed to high doses of lipase, or the methacrylic acid copolymer Eudragit L30 D55, showed evidence of subclinical damage to the colon. The reproducibility of the sonographic measurements was poor.  相似文献   
40.
Elevated homocysteine (Hcy) levels are observed in two apparently unrelated diseases: neural-tube defects (NTD) and premature vascular disease. Defective human methionine synthase (MS) could result in elevated Hcy levels. We sequenced the coding region of MS in 8 hyperhomocysteinaemic patients (4 NTD patients and 4 patients with pregnancies complicated by spiral arterial disease, SAD). We identified only one mutation resulting in an amino acid substitution: an A-->G transition at bp 2756, converting an aspartic acid (D919) into a glycine (G). We screened genomic DNA for the presence of this mutation in 56 NTD patients, 69 mothers of children with NTD, 108 SAD patients and 364 controls. There was no increased prevalence of the GG and AG genotypes in NTD patients, their mothers or SAD patients. The D919G mutation does not seem to be a risk factor for NTD or vascular disease. We then examined the mean Hcy levels for each MS genotype. There was no correlation between GG- or AG-genotype and Hcy levels. The D919G mutation is thus a fairly prevalent, and probably benign polymorphism. This study, though limited, provides no evidence for a major involvement of MS in the aetiology of homocysteine-related diseases such as NTD or vascular disease.   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