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21.
ELISA for the detection of specific IgM and IgG in human leptospirosis 总被引:14,自引:0,他引:14
ELISA was used to detect specific IgM and IgG in sera from humans with current or past leptospirosis. A serological pattern of a high IgM titre (greater than or equal to 1280), or moderately increased IgM (160-640) in conjunction with a low IgG titre (less than or equal to 20), with serovar copenhageni antigen was characteristic for approximately two-thirds of the sera from serovar icterohaemorrhagiae patients obtained in the first two months of the disease. The antigen was the supernatant of a heated and centrifuged culture of leptospires. Antigens were prepared from serovars copenhageni, grippotyphosa, hardjo and patoc. Sera from patients with icterohaemorrhagiae, grippotyphosa and hardjo infections showed cross-reactivity when different antigens were used. In past infections the IgG titres were clearly higher with the homologous antigen. ELISA for IgM and IgG allows the rapid diagnosis of acute leptospirosis. 相似文献
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Jacobus Hendricks Peter Terpstra Peter M. Dammers Rajesh Somasundaram Annie Visser Maaike Stoel Nicolaas A. Bos Frans G. M. Kroese 《Immunogenetics》2010,62(7):479-486
We have mapped and annotated the variable region of the immunoglobulin heavy (IGH) gene locus of the Brown Norway (BN) rat
(assembly V3.4; Rat Genomic Sequence Consortium). In addition to known variable region genes, we found 12 novel previously
unidentified functional IGHV genes and 1 novel functional IGHD gene. In total, the variable region of the rat IGH locus is composed of at least 353 unique IGHV genes, 21 IGHD genes, and 5 IGHJ genes, of which 131, 14, and 4 are potentially functional genes, respectively. Of all species studied so far, the rat seems
to have the highest number of functional IGHV genes in the genome. Rat IGHV genes can be classified into 13 IGHV families based on nucleotide sequence identity. The variable region of the BN rat spans
a total length of approximately 4.9 Mb and is organized in a typical translocon organization. Like the mouse, members of the
various IGHV gene families are more or less grouped together on the genome, albeit some members of IGHV gene families are
found intermingled with each other. In the rat, the largest IGHV gene families are IGHV1, IGHV2, and IGHV5. The overall conclusion
is that the genomic organization of the variable region of the rat IGH locus is strikingly similar to that of the mouse, illustrating
the close evolutionary relationship between these two species. 相似文献
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The mammalian in vivo micronucleus assay is widely used as part of the genotoxicity testing battery required during the development of new drugs. As such, the in vivo micronucleus assay has been used in a battery of assays for the assessment of cigarette ingredients or design modifications to help ensure that there is no increase in risk or any new risk introduced by these additions or modifications. The present series of studies was conducted to optimize and evaluate this assay for the assessment of the effects of mainstream smoke on the micronucleus frequency in the bone marrow and peripheral blood of rats. In a first experiment, the optimal conditions for performing the micronucleus assay in these tissues were determined. This was done by use of two compounds known for their micronucleus-inducing activity, i.e., the clastogen cyclophosphamide and the aneugen colchicine. In a second experiment, the effects of tube restraint on untreated control rats were investigated. In a third experiment, the optimal conditions were used to assess the clastogenic/aneugenic activity of cigarette smoke in Sprague-Dawley rats. The rat micronucleus assay in both bone marrow and peripheral blood is able to detect clastogenic and aneugenic activity. The flow cytometric determination of micronucleated cells in rat blood is at least as sensitive as determinations in bone marrow. No statistically significant differences were observed in micronucleus frequencies between rats with and without the additional stress of tube restraint; however, the cautious approach would be to use a fresh-air-exposed group (with tube restraint) as the negative control in inhalation experiments. Using the conditions identified as optimal in the above-mentioned experiments, the micronucleus assay was not able to detect effects induced by smoke from conventional cigarettes. Nevertheless, the micronucleus assay will remain a valuable tool as part of a testing battery used to investigate possible adverse effects related to product modifications. 相似文献
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Marcio Ender Karolyn Terpstra James D. Kelly 《Molecular breeding : new strategies in plant improvement》2008,21(2):149-157
A marker-assisted selection (MAS) study was conducted on two recombinant inbred line (RIL) populations of common bean (Phaseolus vulgaris) to test the effectiveness of MAS for resistance to white mold (Sclerotinia sclerotiorum). Markers for quantitative trait loci (QTL) on linkage groups B2 and B7 that were previously associated with resistance and
plant architectural avoidance traits in the resistant parent Bunsi were chosen. In the Bunsi/Midland population 10 RILs included
in the MAS selected group developed significantly less disease than the control group based on two years of field evaluation
under white mold pressure. Growth habit had no significant effect on disease severity or incidence. In the Bunsi/Raven RIL
population, disease scores in the MAS selected group were significantly lower than scores in the control group over two years.
Additional progress in enhancing resistance to white mold was detected when yield and plant architecture were included in
the selection process. Lower disease scores among RILs were observed when comparisons were made to RILs selected using MAS
alone. Yield is an important trait that should be considered when selecting for resistance to white mold. Finally the potential
of Bunsi as a genetic donor of QTL for white mold resistance was confirmed in both populations studied. This study supported
the effectiveness of MAS to enhance selection for a complexly inherited trait such as resistance to white mold in common bean. 相似文献
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Functional properties of T cells in patients with chronic T gamma lymphocytosis and chronic T cell neoplasia 总被引:6,自引:0,他引:6
H C Rümke F Miedema I J ten Berge F Terpstra H J van der Reijden R J van de Griend H G de Bruin A E von dem Borne J W Smit W P Zeijlemaker C J Melief 《Journal of immunology (Baltimore, Md. : 1950)》1982,129(1):419-426
The expanded T cell populations of 10 patients with either T gamma lymphocytosis (five patients) or proven chronic T cell malignancy (five patients) were analyzed with respect to functional activity in vitro, including proliferative responses to mitogens, cytotoxic activity (killer [K] and natural killer [NK] cell activity), and regulatory activity on pokeweed mitogen- (PWM) induced immunoglobulin (Ig) synthesis (help and suppression) in comparison with marker phenotypes. In each of the five patients with T gamma lymphocytosis, only one out of three functionally distinct cell types was found: T gamma-K cells, T gamma-S cells, or T gamma-NK/K cells, which mediated K-cell activity, suppressive activity, and both NK and K cell activity, respectively. An expanded T gamma-K cell population was demonstrated in three patients with neutropenia with or without recurrent infections. T gamma-S cells were found in a patient with severe hypogammaglobulinemia, and T gamma-NK/K cells in one patient with asymptomatic lymphocytosis. T gamma-K and T gamma-S cells had a similar surface-marker profile (E+ or E-, Fc gamma+, OKT1-3+4-8+I1-M1-), whereas that of T gamma-NK/K cells was different (E+, Fc gamma+, OKT1-3-4-8-I1+M1+). Longitudinal studies of three untreated patients with T gamma-K lymphocytosis showed that the abnormalities were persistent but not progressive. In contrast, five patients with chronic T cell malignancy (two with T-CLL, two with cutaneous T cell lymphoma [CTCL], and one with T-PLL) all had progressive disease. The neoplastic cells in these cases were E+, Fc gamma-OKT1+4+6- with variable expression of the OKT3 and OKT8 markers. The only functional activity observed in these cells was suppressive activity by OKT3-4+8- cells from a patient with CTCL. 相似文献