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Restrictin is a chick neural extracellular matrix protein implicated in neural cell attachment and found to be associated with the cell surface recognition protein F11. Here we show by cDNA cloning that restrictin is a large multidomain protein composed of 4 structural motifs. At the N-terminus restrictin contains a cysteine-rich segment of about 140 aa that might link restrictin monomers into oligomers. This region is followed by 4.5 epidermal growth factor-like repeats and then by 9 consecutive motifs that are similar to fibronectin type III motifs. At the C-terminus restriction is related to the beta and gamma chains of fibrinogen, including similarity to a calcium-binding segment. Restrictin shows substantial sequence similarity with tenascin (cytotactin) throughout the polypeptide, and like tenascin, it forms oligomeric structures, as revealed by electron microscopy of immunoaffinity-purified restriction. The cell attachment site of restrictin is mapped to the C-terminal region by antibody perturbation experiments. 相似文献
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N. Wille 《Plant Systematics and Evolution》1903,53(3):89-95
Ohne Zusammenfassung 相似文献
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Marcos Paulo Wille Thaís Guimar?es Guilherme Henrique Campos Furtado Arnaldo Lopes Colombo 《Memórias do Instituto Oswaldo Cruz》2013,108(3):288-292
Candida species are an important cause of bloodstream infections (BSI). To evaluate the epidemiological, clinical and microbiological aspects of two cohorts {1994-1999 [period 1 (P1) ]; 2000-2004 [period 2 (P2) ]} of candidaemic patients, we performed a retrospective analysis from a laboratory-based survey. A total of 388 candidaemias were identified, with an incidence of 0.20/1,000 patient-days and a significant increase in P2 vs. P1 (0.25 vs. 0.15, p = 0.04). Cancer and prior antibiotic use were frequent and Candida albicans was the most prevalent species found (42.4%). Resistance to fluconazole was found in 2.47% of the strains. No differences were observed in the species distribution of Candida during the study periods. In the P2 cohort, there were higher prevalence of elderly individuals, cardiac, pulmonary and liver diseases, renal failure, central venous catheters and antibiotic therapy. In P1, there were higher prevalence of neurological diseases and chemotherapy. The crude mortality was 55.4%. In conclusion, our incidence rates remained high. Furthermore, the distribution pattern of Candida species and the fluconazole resistance profile remained unchanged. Moreover, we found a clear trend of higher prevalence of candidaemia among the elderly and among patients with comorbidities. Finally, it is necessary to discuss strategies for the prevention and control of Candida BSI in Brazil. 相似文献
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Mastooreh Chamanian Katarzyna J. Purzycka Paul T. Wille Janice S. Ha David McDonald Yong Gao Stuart F.J. Le Grice Eric J. Arts 《Cell host & microbe》2013,13(2):181-192
Highlights? A retroviral RNA packaging element (GRPE) overlaps the Gag-Pol ribosomal frameshift site ? Without two stem loops in GRPE, genomic RNA encapsidation is decreased >50-fold ? Downregulating the translation termination factor eRF1 produces defective virus particles ? GPRE links ribosome frameshifting and effective retroviral packaging 相似文献
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Four physiological parameters (haemolymph-juvenile hormone titre, protein concentration, vitellogenin concentration, and pharyngeal gland dry weight) were examined in the following categories of queenright adult worker bees: summer bees 1–40 days old, winter bees 80–130 days old, 12–100-day old bees at the beginning of winter, 100–195-day old bees at the end of winter, and 1–100-day old bees experimentally induced to live longer in summer.In contrast to the continuously increasing titre of juvenile hormone in ageing summer bees, winter bees kept a constant low level. In bees at the beginning of winter, the hormone titre never reached high values. However, at the end of winter it rose from a low to a high level, comparable with the high titre of 24–40-day old summer bees. In experimentally induced longlived bees in summer, the juvenile hormone titre did not increase as in normal summer bees but remained low as in bees at the beginning of winter. Among the known natural juvenile hormones, only juvenile hormone III was present in the haemolymph of winter bees.The results support the hypothesis of polyphenism being regulated by the titre of juvenile hormone in the haemolymph. 相似文献
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William Wan Holger Wille Jan St?hr Amy Kendall Wen Bian Michele McDonald Sarah Tiggelaar Joel?C. Watts Stanley?B. Prusiner Gerald Stubbs 《Biophysical journal》2015,108(6):1548-1554
Prions are proteins that adopt self-propagating aberrant folds. The self-propagating properties of prions are a direct consequence of their distinct structures, making the understanding of these structures and their biophysical interactions fundamental to understanding prions and their related diseases. The insolubility and inherent disorder of prions have made their structures difficult to study, particularly in the case of the infectious form of the mammalian prion protein PrP. Many investigators have therefore preferred to work with peptide fragments of PrP, suggesting that these peptides might serve as structural and functional models for biologically active prions. We have used x-ray fiber diffraction to compare a series of different-sized fragments of PrP, to determine the structural commonalities among the fragments and the biologically active, self-propagating prions. Although all of the peptides studied adopted amyloid conformations, only the larger fragments demonstrated a degree of structural complexity approaching that of PrP. Even these larger fragments did not adopt the prion structure itself with detailed fidelity, and in some cases their structures were radically different from that of pathogenic PrPSc. 相似文献
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Ghazaleh Eskandari-Sedighi Nathalie Daude Hristina Gapeshina David W. Sanders Razieh Kamali-Jamil Jing Yang Beipei Shi Holger Wille Bernardino Ghetti Marc I. Diamond Christopher Janus David Westaway 《Molecular neurodegeneration》2017,12(1):72