全文获取类型
收费全文 | 513篇 |
免费 | 24篇 |
国内免费 | 3篇 |
专业分类
耳鼻咽喉 | 2篇 |
儿科学 | 45篇 |
妇产科学 | 6篇 |
基础医学 | 74篇 |
口腔科学 | 7篇 |
临床医学 | 25篇 |
内科学 | 100篇 |
皮肤病学 | 4篇 |
神经病学 | 33篇 |
特种医学 | 16篇 |
外科学 | 82篇 |
综合类 | 47篇 |
预防医学 | 27篇 |
眼科学 | 21篇 |
药学 | 13篇 |
中国医学 | 1篇 |
肿瘤学 | 37篇 |
出版年
2023年 | 4篇 |
2022年 | 10篇 |
2021年 | 15篇 |
2020年 | 8篇 |
2019年 | 7篇 |
2018年 | 16篇 |
2017年 | 5篇 |
2016年 | 11篇 |
2015年 | 17篇 |
2014年 | 15篇 |
2013年 | 12篇 |
2012年 | 27篇 |
2011年 | 31篇 |
2010年 | 24篇 |
2009年 | 20篇 |
2008年 | 23篇 |
2007年 | 33篇 |
2006年 | 30篇 |
2005年 | 13篇 |
2004年 | 20篇 |
2003年 | 16篇 |
2002年 | 17篇 |
2001年 | 19篇 |
2000年 | 7篇 |
1999年 | 12篇 |
1998年 | 11篇 |
1997年 | 15篇 |
1996年 | 15篇 |
1995年 | 10篇 |
1994年 | 10篇 |
1993年 | 3篇 |
1992年 | 12篇 |
1991年 | 7篇 |
1990年 | 5篇 |
1989年 | 5篇 |
1988年 | 4篇 |
1987年 | 6篇 |
1986年 | 6篇 |
1985年 | 4篇 |
1984年 | 1篇 |
1982年 | 1篇 |
1981年 | 2篇 |
1980年 | 3篇 |
1979年 | 2篇 |
1977年 | 1篇 |
1976年 | 2篇 |
1975年 | 2篇 |
1968年 | 1篇 |
排序方式: 共有540条查询结果,搜索用时 31 毫秒
1.
2.
3.
Uptake and tissue distribution of mercury in some plant species collected from a contaminated area in India: Its ecological implications 总被引:3,自引:0,他引:3
B. P. Shaw A. K. Panigrahi 《Archives of environmental contamination and toxicology》1986,15(4):439-446
A study was made of the pattern of distribution of mercury in the tissues of some plant species collected around a chlor-alkali factory in India. Different plants accumulated different levels of mercury in their tissues. Accumulation in leaves was the highest, followed by the stem and the root and, in some cases, the root and the stem. A significant correlation was noted between the mercury concentration of the soil and the plant tissues and between different tissues. Grazers (goats, sheep) also accumulated significant levels of mercury in their tissues. 相似文献
4.
5.
Candidaemia: a 10-year study in an Indian teaching hospital 总被引:3,自引:0,他引:3
Retrospective evaluation of candidaemia patients was performed in an Indian teaching hospital over a 10-year period. The incidence of patients with candidaemia increased eleven-fold in the second half of the study period (55 patients) compared with the first half (5 patients). Haematological malignancies (11 patients), neonatal septicaemia (9), cardiac abnormalities and cardiac surgery (9) were the commonest underlying diseases in these patients. Candida albicans (50%), C. guilliermondii (17%), C. tropicalis (15%) and C. parapsilosis (8%) were the most common fungal pathogens isolated from blood culture. Therapy with two or more antibiotics (92%), corticosteroid administration (25%), intravascular catheter use for over 24 h (78%) and neutropenia (48%) were the accountable predisposing factors. Prolonged hospitalization (mean average 22.2 days as compared with 11.2 days in other patients) was an added risk factor in these patients. 相似文献
6.
7.
Inusha Panigrahi Chirag Ahuja Chakshu Chaudhry 《American journal of medical genetics. Part A》2020,182(10):2236-2238
Orofaciodigital syndrome (OFD) can have variable phenotype and presents with oral anomalies, facial dysmorphism, and digital malformations like syndactyly, and polydactyly. Other presentations also include renal and cardiac defects, and central nervous system anomalies like hydrocephalus and cerebellar abnormalities. OFD1 is a X‐linked dominant form of the syndrome presenting in females with mutations in CXorf5 or OFD1 gene. We describe a young child with sparse hairs, milia over face and absence of corpus callosum. Next generation sequencing showed frameshift pathogenic variant in the exon 13 of the OFD1 gene, consistent with diagnosis of OFD1. 相似文献
8.
The capsule and O antigen in Vibrio cholerae O139 Bengal are associated with a genetic region not present in Vibrio cholerae O1. 总被引:11,自引:2,他引:11
下载免费PDF全文
![点击此处可从《Infection and immunity》网站下载免费的PDF全文](/ch/ext_images/free.gif)
L E Comstock D Maneval Jr P Panigrahi A Joseph M M Levine J B Kaper J G Morris Jr J A Johnson 《Infection and immunity》1995,63(1):317-323
Vibrio cholerae O139 Bengal, although closely related to V. cholerae O1 El Tor, produces a polysaccharide capsule and has a distinct O antigen. We have identified a chromosomal region of at least 11 kb, as defined by three TnphoA mutations, that is required for the expression of both polysaccharides. Electron microscopy and sodium dodecyl sulfate-polyacrylamide gel electrophoresis show that these TnphoA mutants have lost the abilities both to express capsule and to produce lipopolysaccharide beyond the core oligosaccharide. Reactivity with O139 typing serum and resistance to serum are also lost in the mutants. DNA probes for this region do not hybridize with O1 V. cholerae but do react with other vibrios, implying that the region was recently acquired. 相似文献
9.
Germline mutations of the CDKN2 gene in UK melanoma families 总被引:4,自引:1,他引:4
Harland M; Meloni R; Gruis N; Pinney E; Brookes S; Spurr NK; Frischauf AM; Bataille V; Peters G; Cuzick J; Selby P; Bishop DT; Bishop JN 《Human molecular genetics》1997,6(12):2061-2067
Germline mutations in CDKN2 on chromosome 9p21, which codes for the cyclin
D kinase inhibitor p16, and more rarely, mutations in the gene coding for
CDK4, the protein to which p16 binds, underlie susceptibility in some
melanoma families. We have sequenced all exons of CDKN2 and analysed the
CDK4 gene for mutations in 27 UK families showing evidence of
predisposition to melanoma. Five different germline mutations in CDKN2 were
found in six families. Three of the mutations (Met53Ile, Arg24Pro and
23ins24) have been reported previously. We have identified two novel CDKN2
mutations (88delG and Ala118Thr) which are likely to be associated with the
development of melanoma, because of their co-segregation with the disease
and their likely functional effect on the CDKN2 protein. In binding assays
the protein expressed from the previously described mutation, Met53Ile, did
not bind to CDK4/CDK6, confirming its role as a causal mutation in the
development of melanoma. Ala118Thr appeared to be functional in this assay.
Arg24Pro appeared to bind to CDK6, but not to CDK4. No mutations were
detected in exon 2 of CDK4, suggesting that causal mutations in this gene
are uncommon. The penetrance of these mutant CDKN2 genes is not yet
established, nor is the risk of non-melanoma cancer to gene carriers.
相似文献
10.
Campylobacter jejuni 81-176 grown in vivo in rabbit ileal loops expresses novel proteins that are not expressed under standard laboratory culture conditions. A new protein with a molecular mass of ca. 180 kDa is expressed at 14, 24, and 48 h of infection. Three other proteins, with molecular masses of ca. 66, 43, and 35 kDa, are overexpressed during different phases of infection. Expression of these proteins stops immediately during the first passage in laboratory media, and they do not elicit a human immune response. Two other proteins, with molecular masses of ca. 84 and 47 kDa, expressed 48 h after infection can be identified by using convalescent sera from human volunteers who were immune to C. jejuni infection upon rechallenge; these proteins were not visualized on sodium dodecyl sulfate-polyacrylamide gel electrophoresis gels by Coomassie blue staining or silver staining. Antibodies to the 84- and 47-kDa proteins are of the immunoglobulin G class. Both preinfection and convalescent human sera react strongly to the C. jejuni flagellin (a 58-kDa protein), suggesting the presence of cross-reactive antibodies to this protein in healthy humans. Major outer membrane protein and flagella may play a role in providing protection against C. jejuni disease, but our data suggest that there are other proteins expressed only during in vivo growth of the organism that elicit a strong immune response in human C. jejuni infections. 相似文献