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981.
J E Moreira A R Hand L A H?kan Borg S Sandler M Welsh N Welsh D L Eizirik 《Virchows Archiv. B, Cell pathology including molecular pathology》1991,60(5):337-344
We have previously described a preferential reduction in the secretory response to nutrient secretagogues in pancreatic mouse islets maintained in culture after in vitro exposure to streptozotocin (SZ). This reduction was associated with an impaired substrate metabolism at the mitochondrial level. To further clarify this issue, mouse pancreatic islets were exposed in vitro to 2.2 mM SZ for 30 min. At 4 h after SZ treatment ultrastructural changes were apparent in the endoplasmic reticulum and Golgi areas of the B-cells. However, 2 and 6 days following SZ exposure the B-cells appeared well preserved, except for a marked decrease in the number of insulin-containing secretory granules. A morphometric analysis of the B-cells 6 days after SZ exposure showed a normal B-cell size and a normal volume fraction of B-cell mitochondria. However, there was a decrease in total islet size and a 13% decrease in the volume fraction of B-cells in the islets. These mouse islets exhibited a decreased content of the mitochondrial DNA-encoded cytochrome b mRNA, as evaluated by dot-blot analysis. As a whole, the data obtained indicate that SZ treatment does not induce a decrease in the number of mitochondria or long-lasting ultrastructural damage to this organelle. However, there is a clear decrease in the cytochrome b mRNA, suggesting that SZ can induce damage to the mitochondrial DNA. 相似文献
982.
Wendy W. J. van de Sande Ahmed H. Fahal Michael Goodfellow El Sheikh Mahgoub Oliverio Welsh Ed E. Zijlstra 《PLoS neglected tropical diseases》2014,8(7)
Treatment of mycetoma depends on the causative organism and since many organisms, both actinomycetes (actinomycetoma) and fungi (eumycetoma), are capable of producing mycetoma, an accurate diagnosis is crucial. Currently, multiple diagnostic tools are used to determine the extent of infections and to identify the causative agents of mycetoma. These include various imaging, cytological, histopathological, serological, and culture techniques; phenotypic characterisation; and molecular diagnostics. In this review, we summarize these techniques and identify their merits and pitfalls in the identification of the causative agents of mycetoma and the extent of the disease. We also emphasize the fact that there is no ideal diagnostic tool available to identify the causative agents and that future research should focus on the development of new and reliable diagnostic tools. 相似文献
983.
Wendy W. J. van de Sande El Sheikh Maghoub Ahmed H. Fahal Michael Goodfellow Oliverio Welsh Ed Zijlstra 《PLoS neglected tropical diseases》2014,8(3)
Mycetoma is a tropical disease which is caused by a taxonomically diverse range of actinomycetes (actinomycetoma) and fungi (eumycetoma). The disease was only recently listed by the World Health Organization (WHO) as a neglected tropical disease (NTD). This recognition is the direct result of a meeting held in Geneva on February 1, 2013, in which experts on the disease from around the world met to identify the key research priorities needed to combat mycetoma. The areas that need to be addressed are highlighted here. The initial priority is to establish the incidence and prevalence of the disease in regions where mycetoma is endemic, prior to determining the primary reservoirs of the predominant causal agents and their mode of transmission to susceptible individuals in order to establish novel interventions that will reduce the impact of the disease on individuals, families, and communities. Critically, economical, reliable, and effective methods are required to achieve early diagnosis of infections and consequential improved therapeutic outcomes. Molecular techniques and serological assays were considered the most promising in the development of novel diagnostic tools to be used in endemic settings. Improved strategies for treating eumycetoma and actinomycetoma are also considered. 相似文献
984.
Selection and characterization of ricin toxin A-chain mutations in Saccharomyces cerevisiae. 总被引:12,自引:2,他引:10
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A Frankel D Schlossman P Welsh A Hertler D Withers S Johnston 《Molecular and cellular biology》1989,9(2):415-420
A DNA sequence encoding the A chain of ricin toxin (RTA) from the castor bean plant, Ricinus communis, was placed under GAL1 promoter control and transformed into Saccharomyces cerevisiae. Induction of expression of RTA was lethal. This lethality was the basis for a selection of mutations in RTA which inactivated the toxin. A number of mutant alleles which encoded cross-reactive material were sequenced. Eight of the first nine mutant RTAs studied showed single-amino-acid changes involving residues located in the proposed active-site cleft. 相似文献
985.
986.
987.
Changes in distribution of enzymes within the liver lobule during adaptive increases 总被引:9,自引:0,他引:9
F A Welsh 《The journal of histochemistry and cytochemistry》1972,20(2):107-111
988.
Fat embolism following major trauma may be associated with a clinical syndrome with widespread pulmonary and systemic manifestations, the most serious being profound hypoxia with secondary atelectasis, pulmonary edema and pulmonary hypertension, and cerebral depression. Though the origin of the embolic fat is debated, there is evidence to support its origin from both the bone marrow and intravascular chylomicron coalescence.The clinical manifestations are largely explained by a prime assault upon the lung parenchyma and alteration in platelet characteristics.Early recognition and treatment of the condition is essential, adequate oxygenation being of prime importance. Steroids and heparin have been found to be of benefit. 相似文献
989.
R M Welsh H Yang J F Bukowski 《BioEssays : news and reviews in molecular, cellular and developmental biology》1988,8(1):10-13
Interferon (IFN) induced during a virus infection mediates antiviral effects both by direct inhibition of virus replication and by influencing the proliferation, differentiation, and chemotaxis of cyto-toxic lymphocytes which control the infection. Cells from tissue taken from virus-infected mice are conditioned by IFN to resist lysis by natural killer (NK) cells, while they become increasingly susceptible to lysis by cytotoxic Tlymphocytes (CTL). This is due to marked IFN-induced biochemical changes, including an up-regulation of major histocompatibility antigens, which are targets for CTL. Cytopathic viruses, which inhibit cellular RNA and protein synthesis, render target cells refractory to IFN-mediated protection against NK cells, thereby providing a mechanism for NK cells to mediate antiviral effect by preferentially lysing virus-infected but not uninfected cells. 相似文献
990.
Ziqian Liang Ronald PC Wong Lin Hong Li Hesheng Jiang Hao Xiao Gang Li 《Proteome science》2008,6(1):2