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161.
162.
A systematic genetic assessment of 1,433 sequence variants of unknown clinical significance in the BRCA1 and BRCA2 breast cancer-predisposition genes 下载免费PDF全文
Easton DF Deffenbaugh AM Pruss D Frye C Wenstrup RJ Allen-Brady K Tavtigian SV Monteiro AN Iversen ES Couch FJ Goldgar DE 《American journal of human genetics》2007,81(5):873-883
Mutation screening of the breast and ovarian cancer-predisposition genes BRCA1 and BRCA2 is becoming an increasingly important part of clinical practice. Classification of rare nontruncating sequence variants in these genes is problematic, because it is not known whether these subtle changes alter function sufficiently to predispose cells to cancer development. Using data from the Myriad Genetic Laboratories database of nearly 70,000 full-sequence tests, we assessed the clinical significance of 1,433 sequence variants of unknown significance (VUSs) in the BRCA genes. Three independent measures were employed in the assessment: co-occurrence in trans of a VUS with known deleterious mutations; detailed analysis, by logistic regression, of personal and family history of cancer in VUS-carrying probands; and, in a subset of probands, an analysis of cosegregation with disease in pedigrees. For each of these factors, a likelihood ratio was computed under the hypothesis that the VUSs were equivalent to an "average" deleterious mutation, compared with neutral, with respect to risk. The likelihood ratios derived from each component were combined to provide an overall assessment for each VUS. A total of 133 VUSs had odds of at least 100 : 1 in favor of neutrality with respect to risk, whereas 43 had odds of at least 20 : 1 in favor of being deleterious. VUSs with evidence in favor of causality were those that were predicted to affect splicing, fell at positions that are highly conserved among BRCA orthologs, and were more likely to be located in specific domains of the proteins. In addition to their utility for improved genetics counseling of patients and their families, the global assessment reported here will be invaluable for validation of functional assays, structural models, and in silico analyses. 相似文献
163.
Johnson LE Frye TP Chinnasamy N Chinnasamy D McNeel DG 《Cancer immunology, immunotherapy : CII》2007,56(6):885-895
Prostatic acid phosphatase (PAP) is a prostate cancer tumor antigen and a prostate-specific protein shared by rats and humans.
Previous studies indicated that Copenhagen rats immunized with a recombinant vaccinia virus expressing human PAP (hPAP) developed
PAP-specific cytotoxic T cells (CTL) with cross reactivity to rat PAP (rPAP) and evidence of prostate inflammation. Viral
delivery of vaccine antigens is an active area of clinical investigation. However, a potential difficulty with viral-based
immunizations is that immune responses elicited to the viral vector might limit the possibility of multiple immunizations.
In this paper, we investigate the ability of another genetic immunization method, a DNA vaccine encoding PAP, to elicit antigen-specific
CD8+ T cell immune responses. Specifically, Lewis rats were immunized with either a plasmid DNA-based (pTVG-HP) or vaccinia-based
(VV-HP) vaccine each encoding hPAP. We determined that rats immunized with a DNA vaccine encoding hPAP developed a Th1-biased
immune response as indicated by proliferating PAP-specific CD4+ and CD8+ cells and IFNγ production. Rats immunized with vaccinia
virus encoding PAP did not develop a PAP-specific response unless boosted with a heterologous vaccination scheme. Most importantly,
multiple immunizations with a DNA vaccine encoding the rat PAP homologue (pTVG-RP) could overcome peripheral self-tolerance
against rPAP and generate a Th1-biased antigen-specific CD4+ and CD8+ T cell response. Overall, DNA vaccines provide a safe
and effective method of generating prostate antigen-specific T cell responses. These findings support the investigation of
PAP-specific DNA vaccines in human clinical trials. 相似文献
164.
Two insect species from China, Gonioctena tredecimmaculata (Jacoby) (Coleoptera: Chrysomelidae) and Ornatalcides (Mesalcidodes) trifidus (Pascoe) (Coleoptera: Curculionidae), were studied in quarantine in the United States as potential biological control agents for kudzu, Pueraria montana variety lobata (Willd.) Maesen and S. Almeida. Adults of G. tredecimmaculata were ovoviviparous and reproduced throughout the summer, producing offspring that had an obligate adult diapause. In no-choice tests, adult and larval G. tredecimmaculata rejected most of the plant species tested, but consumed foliage and completed their life cycle on soybean (Glycine max L. Merr.) and on a native woodland plant, hog-peanut (Amphicarpaea bracteata L. Fernald), which are in the same subtribe as kudzu (Glycininae). Insects showed similar responses to field- and greenhouse-grown soybean and kudzu foliage, despite measurable differences in leaf traits: field-grown foliage of both plants had greater leaf toughness, higher total carbon content, higher trichome density, and lower water content than greenhouse foliage. O. trifidus adults also rejected most of the plants tested but fed on and severely damaged potted soybean and hog-peanut plants in addition to kudzu. Further tests in China are needed to determine whether these species will accept nontarget host plants under open-field conditions. 相似文献
165.
Gary W. Ferguson J. R. Jones W. H. Gehrmann S. H. Hammack L. G. Talent R. D. Hudson E. S. Dierenfeld M. P. Fitzpatrick F. L. Frye M. F. Holick T. C. Chen Z. Lu T. S. Gross J. J. Vogel 《Zoo biology》1996,15(3):279-299
To assess the importance of diet and light for indoor maintenance, hatchling panther chameleons were reared for 1 year on crickets fed diets that differed in vitamin concentrations and in different light environments. Dietary transfer of vitamins from the cricket diet to the lizards via the crickets was quantified, as was UV irradiance. There was a statistically significant dietary enhancement of growth by both vitamins on males. UV-A irradiation significantly suppressed growth of females. Low vitamin A shortened life span and resulted in a number of gross and histological pathologies. Hepatocellular lipidosis, indicating a possible toxicosis, occurred with all diets and light treatments. Higher vitamin A resulted in mild soft-tissue mineralization, and high vitamin D shortened the life span of females. Low vitamin A drastically reduced reproduction in both sexes. The intermediate levels of dietary vitamins resulted in the best production of viable eggs by females. However, without high UV-B irradiation, all viable eggs died at term and contained different vitamin levels than hatching eggs from wild-caught females. Baseline levels of egg calcium are given for hatching eggs from wild-caught females. Modifications in current husbandry procedures are recommended. © 1996 Wiley-Liss, Inc. 相似文献
166.
Decomposition of seawater-irrigated halophytes: implications for potential carbon storage 总被引:10,自引:0,他引:10
Plants were cultivated in a nutrient solution containing increasing cadmium concentrations (i.e. 0.001–25 µM), under strictly controlled growth conditions. Changes in both growth parameters and enzyme activities, directly or indirectly related to the cellular free radical scavenging systems, were studied in roots and leaves of 14-day-old maize plants (Zea mays L., cv. Volga) as a result of Cd uptake. A decrease in both shoot length and leaf dry biomass was found to be significant only when growing on 25 µM Cd, whereas concentrations of chlorophyll pigments in the 4th leaf decreased from 1.7 µM Cd on. Changes in enzyme activities occurred at lower Cd concentrations in solution leading to lower threshold values for Cd contents in plants than those observed for growth parameters. Peroxidase (POD; E.C. 1.11.1.7) activity increased in the 3rd and 4th leaf, but not in roots. In contrast, glucose-6-phosphate dehydrogenase (G6PDH; E.C. 1.1.1.49), isocitrate dehydrogenase (ICDH; E.C. 1.1.1.42) and malic enzyme (ME; E.C. 1.1.1.40) activities decreased in the 3rd leaf. According to the relationship between the POD activity and the Cd content, a toxic critical value was set at 3 mg Cd per kg dry matter in the 3rd leaf and 5 mg Cd per kg dry matter in the 4th. Anionic POD were determined both in root and leaf protein extracts; however, no changes in the isoperoxidase pattern were detected in case of Cd toxicity. Results show that in contrast with growth parameters, the measurement of enzyme activities may be included as early biomarkers in a plant bioassay to assess the phytotoxicity of Cd-contaminated soils on maize plants. 相似文献
167.
168.
A paradox exists in modern schooling: students are simultaneously more positive about the future and more depressed than ever. We suggest that these two phenomena may be linked. Two studies demonstrated that students are more likely to be depressed when educational aspirations exceed expectations. In Study 1 (N = 85) aspiring to a thesis grade higher than one expected predicted greater depression at the beginning and end of the academic year. In Study 2 (N = 2820) aspiring to a level of education (e.g., attending college) higher than one expected to achieve predicted greater depression cross-sectionally and five years later. In both cases the negative effects of aspiring high while expecting low persisted even after controlling for whether or not students achieved their educational aspirations. These findings highlight the danger of teaching students to aspire higher without also investing time and money to ensure that students can reasonably expect to achieve their educational goals. 相似文献
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170.