全文获取类型
收费全文 | 949篇 |
免费 | 93篇 |
专业分类
1042篇 |
出版年
2022年 | 11篇 |
2021年 | 23篇 |
2020年 | 11篇 |
2019年 | 11篇 |
2018年 | 16篇 |
2017年 | 10篇 |
2016年 | 19篇 |
2015年 | 40篇 |
2014年 | 54篇 |
2013年 | 60篇 |
2012年 | 57篇 |
2011年 | 57篇 |
2010年 | 34篇 |
2009年 | 32篇 |
2008年 | 49篇 |
2007年 | 44篇 |
2006年 | 35篇 |
2005年 | 33篇 |
2004年 | 32篇 |
2003年 | 24篇 |
2002年 | 36篇 |
2001年 | 23篇 |
2000年 | 20篇 |
1999年 | 17篇 |
1998年 | 13篇 |
1997年 | 16篇 |
1996年 | 6篇 |
1994年 | 6篇 |
1993年 | 6篇 |
1992年 | 13篇 |
1991年 | 11篇 |
1990年 | 14篇 |
1989年 | 10篇 |
1988年 | 10篇 |
1987年 | 6篇 |
1986年 | 13篇 |
1985年 | 15篇 |
1984年 | 14篇 |
1983年 | 9篇 |
1982年 | 8篇 |
1981年 | 6篇 |
1979年 | 15篇 |
1975年 | 6篇 |
1974年 | 17篇 |
1972年 | 11篇 |
1971年 | 9篇 |
1970年 | 6篇 |
1969年 | 5篇 |
1967年 | 5篇 |
1966年 | 9篇 |
排序方式: 共有1042条查询结果,搜索用时 15 毫秒
1.
2.
3.
4.
5.
M S Jawahar S Sivasubramanian V K Vijayan C V Ramakrishnan C N Paramasivan V Selvakumar S Paul S P Tripathy R Prabhakar 《BMJ (Clinical research ed.)》1990,301(6748):359-362
OBJECTIVE--To assess the efficacy of a short course chemotherapy regimen for treating tuberculosis of the lymph nodes in children. DESIGN--Open, collaborative, outpatient clinical trial. SETTING--Outpatient department of the Tuberculosis Research Centre, paediatric surgery departments of the Institute of Child Health and Hospital for Children and the Government Stanley Hospital, Madras, South India. PATIENTS--Children aged 1-12 years with extensive, multiple site, superficial tuberculous lymphadenitis confirmed by biopsy (histopathology or culture). INTERVENTIONS--Patients were treated with a fully supervised intermittent chemotherapy regimen consisting of streptomycin, rifampicin, isoniazid, and pyrazinamide three times a week for two months followed by streptomycin and isoniazid twice a week for four months on an outpatient basis. Surgery was limited to biopsy of nodes for diagnosis and assessment. MAIN OUTCOME MEASURES--Response to chemotherapy was assessed by regression of lymph nodes and healing of sinuses and abscesses during treatment and follow up. Compliance with treatment and frequency of adverse reactions were also estimated. RESULTS--197 Patients were admitted to the study and 168 into the analysis. The regimen was well tolerated and compliance was good with 101 (60%) patients receiving the prescribed chemotherapy within 15 days of the stipulated period of six months. Those whose chemotherapy extended beyond that period received the same total number of doses. Clinical response was favourable in most patients at the end of treatment. Sinuses and abscesses healed rapidly. Residual lymphadenopathy (exceeding 10 mm diameter) was present in 50 (30%) patients at the end of treatment; these nodes were biopsied. Fresh nodes, increase in size of nodes, and sinuses and abscesses occurred both during treatment and follow up. After 36 months of follow up after treatment only 5 (3%) patients required retreatment for tuberculosis. CONCLUSION--Tuberculous lymphadenitis in children can be successfully treated with a short course chemotherapy regimen of six months. 相似文献
6.
Administration of low amounts of ethanol for a prolonged period increases rat brain synaptosomal (Na+–K+)-ATPase activity, the increase being less in the protein deficient rats. The adaptive mechanism to offset the stress imposed by the continued presence of ethanol seems to be depressed by low plane of nutrition. In vivo and in vitro effects of ethanol on (Na+–K+)ATPase seems to be different. 相似文献
7.
Effect of Maternal Alcohol Consumption on the Lipid Composition of CNS in the Offspring 总被引:1,自引:0,他引:1
T. Lalitha Krishna Kumar C. V. Ramakrishnan S. D. Telang 《Journal of neurochemistry》1988,50(5):1346-1351
Maternal alcohol consumption at a level that does not affect calorie intake increases cholesterol concentration and content as well as incorporation of labeled glucose into cholesterol in the brain and spinal cord of newborn rat pups. Continued consumption of alcohol during lactation also affects the galactolipid concentration in the brain and spinal cord of pups at 21 days of age, and this increase seems mainly to be due to an increase in content of myelin lipids. Analysis of myelin shows that the concentration of phospholipids also increases in this fraction. The increase in incorporation of labeled glucose into these membrane lipids suggests an increase in the synthesis of these lipids, which prevents fluidization of the membrane by alcohol. That in the brainstem the increase in levels of cholesterol and galactolipids is higher than in other regions and that there is also an increase in content of sphingomyelin, phosphatidylcholine, and phosphatidylethanolamine suggest that the brainstem needs better protection against fluidization. 相似文献
8.
Crystal and molecular structure of the ammonium salt of the dinucleoside monophosphate d(CpG) 总被引:1,自引:0,他引:1
The crystal and molecular structure of the ammonium salt of deoxycytidylyl-(3'-5')-deoxyguanosine has been determined from 0.85 A resolution single crystal X-ray diffraction data. The crystals obtained by acetone diffusion technique at -20 degrees C, are orthorhombic, P212121, a = 12.880(2), b = 17444(2) and c = 27.642(2) A. The structure was solved by high resolution Patterson and Fourier methods and refined to R = 0.136. There are two d(CpG) molecules in the asymmetric unit forming a mini left handed Z-DNA helix. This is in contrast to the earlier reported forms of d(CpG) where the molecules form self base paired duplexes. There are two ammonium ions in the asymmetric unit. The major groove NH+4 ion interacts with N7 of guanines through water bridges besides making H-bonded interactions directly with the phosphate oxygen atoms. A second NH+4 ion is found in the minor groove interacting directly with the phosphate oxygen atoms. Symmetry related molecules pack in such a way that the cytosine base stacks on cytosine and guanine base on guanine. Our structure demonstrates that alternating d(CpG) sequences have the ability to adopt the left handed Z-DNA structure even at the dimer level i.e., in a sequence which is only two base pairs long. 相似文献
9.
10.
ASTA Z 7557 potentiated the ex vivo efficiency of a T-cell directed immunotoxin containing pokeweed antiviral protein (PAP). We used an immunotoxin of pan-T monoclonal antibody 3-A1 directed against p41 antigen expressed both on normal and leukemic T-cells. Treatment with 3A1-PAP in combination with ASTA Z 7557 produced 7-8 logs elimination of target lymphoblastic leukemia cells. Our data suggest that this new strategy shows potential for more effective ex vivo marrow purging in autologous marrow transplantation for acute lymphoblastic leukemia. 相似文献