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31.
The tissue localization patterns of radiolabeled dividing cells obtained from gut lamina propria (LP), mesenteric (MLN) and peripheral (PLN) lymph nodes, and Peyer's patches (PP) were studied in guinea pigs using an adoptive lymphocyte transfer method. Within 24 hr 125I-deoxyuridine-labeled cells from donor LP and MLN, but not PLN, selectively localized in recipient gut and MLN. In contrast, donor PLN lymphoblasts returned to their sites of origin while labeled PP donor cells exhibited no specific tissue localization. These findings suggest that the gut LP, like the MLN, contains a population of cells which, unlike those in the PP and PLN, has the capacity to selectively localize in mucosal tissues. From this and other published work, we conclude that within the LP there is a population of cells at different stages of differentiation with a propensity to populate mucosae. 相似文献
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Studies on the catabolism of Ng-methylarginine, Ng, Ng-dimethylarginine and Ng, Ng-dimethylarginine in the rabbit. 总被引:11,自引:0,他引:11 下载免费PDF全文
J R McDermott 《The Biochemical journal》1976,154(1):179-184
1. The routes of elimination of Ng-methylarginine, Ng, Ng-dimethylarginine and Ng, Ng-dimethylarginine were investigated in the rabbit. 2. Analyses showed low plasma concentrations of these amino acids (around 1 nmol/ml) and ratios similar to those found in tissue proteins. The concentrations of these amino acids in extracts of brain, kidney, liver and spleen were similar except that liver had a lower concentration of Ng-methylarginine and Ng, Ng-dimethylarginine. Cerebrospinal fluid contained traces of each amino acid. 相似文献
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F McDermott B Roudnew 《Virchows Archiv. B, Cell pathology including molecular pathology》1978,28(2):179-185
The influence of 40% small intestinal resection on epithelial cell population kinetics of isolated ileal loops (Thirty-Vella fistulae) was investigated by autoradiography with H3-thymidine in the rat. Sixty days after resection increases were found in the size of the proliferative (0.05 less than P less than 0.1) and villous (P less than 0.01) zones. In isolated ileal loops of animals not subjected to 40% small bowel resection proliferative and villous zones were reduced in size in comparison to those of ileum in continuity in a group subjected to jejunal transection and anastomosis (P less than 0.002). The findings support the hypothesis that villous size is increased after resection by the action of a systemic factor. However, they provide only limited evidence for the influence of a systemic factor on crypt cell proliferation. 相似文献
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Nadia B. Hassounah Ray Nagle Kathylynn Saboda Denise J. Roe Bruce L. Dalkin Kimberly M. McDermott 《PloS one》2013,8(7)
Prostate cancer is the second most commonly diagnosed cancer in men worldwide. Little is known about the role of primary cilia in preinvasive and invasive prostate cancer. However, reduced cilia expression has been observed in human cancers including pancreatic cancer, renal cell carcinoma, breast cancer, cholangiocarcinoma, and melanoma. The aim of this study was to characterize primary cilia expression in preinvasive and invasive human prostate cancer, and to investigate the correlation between primary cilia and the Wnt signaling pathway. Human prostate tissues representative of stages of prostate cancer formation (normal prostate, prostatic intraepithelial neoplasia (PIN), and invasive prostate cancer (including perineural invasion)) were stained for ciliary proteins. The frequency of primary cilia was determined. A decrease in the percentage of ciliated cells in PIN, invasive cancer and perineural invasion lesions was observed when compared to normal. Cilia lengths were also measured to indirectly test functionality. Cilia were shorter in PIN, cancer, and perineural invasion lesions, suggesting dysfunction. Primary cilia have been shown to suppress the Wnt pathway. Increased Wnt signaling has been implicated in prostate cancer. Therefore, we investigated a correlation between loss of primary cilia and increased Wnt signaling in normal prostate and in preinvasive and invasive prostate cancer. To investigate Wnt signaling in our cohort, serial tissue sections were stained for β-catenin as a measure of Wnt signaling. Nuclear β-catenin was analyzed and Wnt signaling was found to be higher in un-ciliated cells in the normal prostate, PIN, a subset of invasive cancers, and perineural invasion. Our results suggest that cilia normally function to suppress the Wnt signaling pathway in epithelial cells and that cilia loss may play a role in increased Wnt signaling in some prostate cancers. These results suggest that cilia are dysfunctional in human prostate cancer, and increase Wnt signaling occurs in a subset of cancers. 相似文献
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To bypass a diverse range of fork stalling impediments encountered during genome replication, cells possess a variety of DNA damage tolerance (DDT) mechanisms including translesion synthesis, template switching, and fork reversal. These pathways function to bypass obstacles and allow efficient DNA synthesis to be maintained. In addition, lagging strand obstacles can also be circumvented by downstream priming during Okazaki fragment generation, leaving gaps to be filled post-replication. Whether repriming occurs on the leading strand has been intensely debated over the past half-century. Early studies indicated that both DNA strands were synthesised discontinuously. Although later studies suggested that leading strand synthesis was continuous, leading to the preferred semi-discontinuous replication model. However, more recently it has been established that replicative primases can perform leading strand repriming in prokaryotes. An analogous fork restart mechanism has also been identified in most eukaryotes, which possess a specialist primase called PrimPol that conducts repriming downstream of stalling lesions and structures. PrimPol also plays a more general role in maintaining efficient fork progression. Here, we review and discuss the historical evidence and recent discoveries that substantiate repriming as an intrinsic replication restart pathway for maintaining efficient genome duplication across all domains of life. 相似文献
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Jonathan C Fuller Pierre Khoueiry Holger Dinkel Kristoffer Forslund Alexandros Stamatakis Joseph Barry Aidan Budd Theodoros G Soldatos Katja Linssen Abdul Mateen Rajput 《EMBO reports》2013,14(4):302-304
The third Heidelberg Unseminars in Bioinformatics (HUB) was held on 18th October 2012, at Heidelberg University, Germany. HUB brought together around 40 bioinformaticians from academia and industry to discuss the ‘Biggest Challenges in Bioinformatics’ in a ‘World Café’ style event. 相似文献
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Beilei Ge Fei Wang Maria Sjölund-Karlsson Patrick F. McDermott 《Journal of microbiological methods》2013
Most Campylobacter infections are self-limiting but antimicrobial treatment (e.g., macrolides, fluoroquinolones) is necessary in severe or prolonged cases. Susceptibility testing continues to play a critical role in guiding therapy and epidemiological monitoring of resistance. The methods of choice for Campylobacter recommended by the Clinical and Laboratory Standards Institute (CLSI) are agar dilution and broth microdilution, while a disk diffusion method was recently standardized by the European Committee on Antimicrobial Susceptibility Testing (EUCAST). Macrolides, quinolones, and tetracyclines are among the common antimicrobials recommended for testing. Molecular determination of Campylobacter resistance via DNA sequencing or PCR-based methods has been performed. High levels of resistance to tetracycline and ciprofloxacin are frequently reported by many national surveillance programs, but resistance to erythromycin and gentamicin in Campylobacter jejuni remains low. Nonetheless, variations in susceptibility observed over time underscore the need for continued public health monitoring of Campylobacter resistance from humans, animals, and food. 相似文献
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