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I. M. Baibekov B. Z. Kasymov T. A. Sagatov 《Bulletin of experimental biology and medicine》1997,123(4):406-409
Intragastral administration of the pesticides Sumi-alpha and Omait to rats significantly increases the number of parietal
microorganisms in the jejunum, ileum, and particularly in the cecum. Electron microscopy shows that parietal microorganisms
invade goblet cells during secretion and then enter prismatic cells via the lateral plasma membrane. The number of parietal
microorganisms entering enterocytes after Sumi-alpha is higher than after less toxic Omait, reaching the maximum 5 h after
administration.
Translated fromByulleten’ Eksperimental’noi Biologii i Meditsiny, Vol. 123, No. 4, pp. 467–470, April, 1997 相似文献
3.
G. A. Van der Weijden M. F. Timmerman E. Reijerse G. N. Wolffe A. J. Van Winkelhoff U. Van der Velden 《Journal of clinical periodontology》1994,21(9):583-588
Abstract. The present study was carried out in a private periodontal practice. 8 clinical criteria were chosen to select patients for microbiological examination. These criteria characterize prominent features of disease which at the start, during, or in the maintenance phase of treatment suggest difficulties in the progress of the periodontal therapy. Based on these clinical characteristics, an inventory was made of the prevalence of the 3 putative periodontal pathogens: Actinobacillus actinomycetemcomitans, Porphyromonas gingivalis, Prevotella intermedia. Out of 320 referred patients 91 patients did meet 1 of the clinical criteria and consequently were selected for microbiological examination. Results showed that young patients (19–30 years) with periodontitis demonstrated the presence of A. actinomycetemcomitans more often (69%: p (0.005) compared to older age cohorts. A. actinomycetemcomitans was found more often when localized breakdown (in particular in the 1 st molar and incisor region) was observed and in patient who responded poorly to scaling and rootplaning. P. gingivalis and P. intermedia were most frequently recovered in patients showing primarily a bone loss pattern of angular defects of 5 mm. Retrospectively, these patients were further categorized, based on full mouth radiographs, in (1) patients with primarily horizontal bone loss and (2) patients with primarily angular bony defects. Results showed that A. actinomycetemcomitans occurred less frequently in patients showing horizontal bone loss ( p (0.05). 相似文献
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A "reverse" hybridization method is described, in which whole chromosomal DNA was extracted from 10-20 colonies of "unknown" strains in pure culture and labelled with digoxigenin by a random primer technique. DNA probes were prepared from a total of 23 strains and hybridized with targets containing 100 ng purified, denatured DNA from 38 reference strains fixed to nitrocellulose. 21/23 digoxigenin-labelled DNA probes successfully detected all members of the homologous species present on filters. Probes to Fusobacterium nucleatum strains 364 and MG detected 3/4 and 1/4 members of this species, respectively; 13/23 probes were 100% specific, but cross reactions between 10 probes and DNA targets from closely related, heterologous species occurred in 15/834 possible instances. False-positive reactions that occurred between closely related species were, however, easily distinguished and did not prevent the accurate identification of probe strains. Digoxigenin-labelled probes were capable of detecting 100 pg of homologous DNA. The reverse hybridization procedure allows identification or grouping of a large number of isolates within 3 days and provides a more economical means of characterizing subgingival isolates than predominant cultivable techniques and conventional phenotypic testing. This method could be adapted for the direct identification of microorganisms in subgingival plaque samples. 相似文献
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I. V. Stupin A. I. Novokshonov A. M. Domborvskii G. G. Belous M. Yu. Ivanov 《Bulletin of experimental biology and medicine》1990,110(4):1407-1409
Department of Experimental Surgery, Interfaculty Laboratory Complex, and Department of Clinical Laboratory Diagnosis, Postgraduate Medical Faculty, N. I. Pirogov Second Moscow Medical Institute. (Presented by Academician of the Academy of Medical Sciences of the USSR V. V. Kupriyanov.) Translated from Byulleten' Éksperimental'noi Biologii i Meditsiny, Vol. 110, No. 10, pp. 413–145, October, 1990. 相似文献
7.
目的 通过分析箭叶淫羊藿Epimediumsagittatum不同生育期根际微生物群落结构及其与主要药用有效成分累积之间的相关性,探讨箭叶淫羊藿根际土壤微生物对其药材有效成分的影响,为箭叶淫羊藿的优质高产栽培提供科学依据。方法 以三年生箭叶淫羊藿的根际土为研究对象,采用高通量测序技术对根际细菌和真菌群落结构进行分析,同时测定根际土壤理化性质、酶活性及不同生育期药材总黄酮、淫羊藿苷等有效成分含量,通过皮尔逊相关性分析探究土壤生态因子与有效成分之间的关系。结果 高通量测序结果显示,箭叶淫羊藿根际细菌优势菌属包括Candidatus_Solibacter、苔藓杆菌属、嗜酸栖热菌属、芽单胞菌属等,其中,Candidatus_Solibacter属在5个生长时期的平均丰度值最高。根际真菌优势菌属中被孢霉属相对丰度占比最大,在花蕾期样品中的丰度值高达44.27%。UPGMA聚类和非度量多维标定法(NMDS)分析表明,花蕾期、盛花期、果实膨大期及盛果期的根际土壤细菌和真菌结构相似,而药材质量稳定期与前4个时期的根际微生物群落结构存在明显差异。同时,皮尔逊相关性分析结果显示:总黄酮含量与有效磷呈显著正... 相似文献
8.
Eight-cell, zona pellucida-intact mouse embryos were exposed to the following substances or procedures that have been reported to have germicidal effects to determine if the embryos would survive and develop under in vitro conditions: the photosensitive substances hematoporphyrin, hematoporphyrin derivative, 8-methoxypsoralen, 4,5,8-trimethylpsoralen, and thiopyronine; the enzymes lipase (0.5%), phospholipase C (2 U/ml), chymotrypsin (0.5%), and trypsin (0.5%); pH 5.0; and helium/neon laser light, visible light, ultraviolet A light, and ultraviolet C light. Under the conditions used, embryos were not adversely affected by hematoporphyrin and/or helium/neon laser light; methoxypsoralen and/or ultraviolet A light; lipase; trypsin; pH 5.0 for 20 min; and visible light. Variable results were obtained from hematoporphyrin derivative with laser light. Thiopyronine, trimethylpsoralen in combination with ultraviolet A light, and ultraviolet C light killed embryos, and chymotrypsin and phospholipase C were harmful at 10- and 15-min exposure times, respectively. 相似文献
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Raivo Uibo Kai Kisand Chen‐Yen Yang M. Eric Gershwin 《APMIS : acta pathologica, microbiologica, et immunologica Scandinavica》2012,120(11):857-871
Primary biliary cirrhosis (PBC) is considered a model autoimmune disease based on several features, including the presence of a highly directed and very specific immune response to mitochondrial autoantigens, a female predominance, a targeted destruction of the biliary epithelium, and homogeneity between patients. It is essentially a chronic progressive cholestatic liver disease characterized by immune‐mediated destruction of small‐ and medium‐sized intrahepatic bile ducts. There is considerable variation in the incidence and prevalence of the disease between regions of the world, although such differences likely reflect not only a true disparity in disease but also differences in awareness; for example, in the United States, PBC is often detected in an asymptomatic stage based on multi‐phasic clinical testing. There has been considerable progress at defining the immune response in this disease, including quantitation of autoreactive T cells against PDC‐E2, the major mitochondrial autoantigen. The overwhelming data suggests that patients develop PBC based on a genetic predisposition and loss of tolerance to one or more environmental agents. In this review, we will present an updated overview of PBC and place it in the context of autoimmunity. 相似文献