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Jack C. Rhyan Pauline Nol Christine Quance Arnold Gertonson John Belfrage Lauren Harris Kelly Straka Suelee Robbe-Austerman 《Emerging infectious diseases》2013,19(12):1992-1995
Bovine brucellosis has been nearly eliminated from livestock in the United States. Bison and elk in the Greater Yellowstone Area remain reservoirs for the disease. During 1990–2002, no known cases occurred in Greater Yellowstone Area livestock. Since then, 17 transmission events from wildlife to livestock have been investigated. 相似文献
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O. O. Nwankiti E. I. Ikeh O. Asala T. Seuberlich 《Transboundary and Emerging Diseases》2013,60(3):279-283
Bovine spongiform encephalopathy (BSE), popularly known as ‘mad cow disease’, led to an epidemic in Europe that peaked in the mid‐1990s. Its impact on developing countries, such as Nigeria, has not been fully established as information on livestock and surveillance has eluded those in charge of this task. The BSE risk to Nigeria’s cattle population currently remains undetermined, which has resulted in international trade restrictions on commodities from the cattle population. This is mainly because of a lack of updated BSE risk assessments and disease surveillance data. To evaluate the feasibility of BSE surveillance in Nigeria, we carried out a pilot study targeting cattle that were presented for emergency or casualty slaughter. In total, 1551 cattle of local breeds, aged 24 months and above were clinically examined. Ataxia, recumbency and other neurological signs were topmost on our list of criteria. A total of 96 cattle, which correspond to 6.2%, presented clinical signs that supported a suspect of BSE. The caudal brainstem tissues of these animals were collected post‐mortem and analysed for the disease‐specific form of the prion protein using a rapid test approved by the International Animal Health Organization (OIE). None of the samples were positive for BSE. Although our findings do not exclude the presence of BSE in Nigeria, they do demonstrate that targeted sampling of clinically suspected cases of BSE is feasible in developing countries. In addition, these findings point to the possibility of implementing clinical monitoring schemes for BSE and potentially other diseases with grave economic and public health consequences. 相似文献
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S. Roperto V. Russo L. Leonardi M. Martano F. Corrado M. G. Riccardi F. Roperto 《Transboundary and Emerging Diseases》2016,63(6):628-634
Bovine papillomavirus type 13 (BPV‐13), a novel Deltapapillomavirus, has been found associated with urothelial tumours of the urinary bladder of cattle grazing on lands infested with bracken fern. BPV‐13 was detected in 28 of 39 urothelial tumours. Diagnosis was based on sequencing of L1 and E5 amplicons from tumour samples. The nucleotide sequences generated from these amplicons showed a 100% homology with the sequences of BPV‐13 L1 and E5 DNA found in Brazil from a fibropapilloma of the ear in a cow and from equine sarcoids in two horses. GenBank accession number of our representative BPV‐13 sequences is JQ798171.1 . Furthermore, mRNA encoding BPV‐13 E5 oncoprotein was also documented, and its expression was also shown by immunohistochemistry and immunofluorescence in the basal and suprabasal urothelial tumour cells. In twenty‐three tumours, BPV‐13 was simultaneously found with BPV‐2, a Deltapapillomavirus genus, species 4. The latter virus was detected by amplifying and sequencing a 154‐bp‐sized DNA fragment of BPV‐2 E5. In addition, BPV‐13 by itself was seen to be expressed in five BPV‐2‐negative urothelial tumours. This study shows that BPV‐13 is present in urothelial tumour cells thus sharing biological properties with BPV‐1 and BPV‐2. Although further studies are needed, BPV‐13 appears to be another worldwide infectious agent responsible for a distressing disease causing severe economic losses in cattle industry. 相似文献
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《Transboundary and Emerging Diseases》2018,65(2):456-464
Bovine anaplasmosis could be caused by several Anaplasma species. The causative agents are transmitted by ticks and haematophagous arthropods with a high impact on both human and animal health. This study was conducted to estimate the infection rate and to characterize Anaplasma spp. in cattle from Algeria. A molecular survey was performed in Setif district (Northeast Algeria) where a total number of 180 cattle blood samples were collected and tested for the presence of Anaplasma spp. by PCR . Positive samples were genetically characterized based on the 16S rRNA and msp4 genes. PCR s revealed that the infection rates of Anaplasma spp., Anaplasma centrale , Anaplasma marginale and Anaplasma bovis were 42.2%; 39.4%; 11.1% and 4.4%, respectively. All tested animals were negative for A. phagocytophilum . Co‐infection occurred in 10% (18/180) of the tested animals, and the most common co‐infection pattern was an association between A. centrale and A. marginale (5.5%). Five cattle (2.7%) were co‐infected by the three Anaplasma species. Holstein animals (58.1%) were more infected by A. centrale than the other breeds (p = .01). The molecular prevalence of A. centrale was significantly higher in males (54.2%) than in females (34.1%) (p = .001). A. marginale msp4 genetic analysis indicated a high sequence diversity of Algerian strains, suggesting the importation of live cattle from different origins. Phylogenetic analysis of the 16S rRNA gene of A. bovis and A. centrale revealed a low degree of genetic diversity. Our study suggests that different species of Anaplasma are simultaneously present in the Algerian cattle. To the best of our knowledge, this is the first molecular study and genetic characterization of Anaplasma spp. in Algerian cattle. 相似文献
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Paula Viviani Adrián L. Lifschitz Jorge P. García María Laura Maté Miguel A. Quiroga Carlos E. Lanusse 《Xenobiotica; the fate of foreign compounds in biological systems》2017,47(11):933-942
1.?Precision-cut liver slices (PCLS) from food-producing animals have not been extensively used to study xenobiotic metabolism, and thus information on this field of research is sparse.2.?The aims of the present work were to further validate the technique of production and culture of bovine PCLS and to characterize the metabolic interaction between the anthelmintic albendazole (ABZ) and the flavin-monooxygenase (FMO) inhibitor methimazole (MTZ).3.?Nine steers were used as donors. PCLS were produced and incubated under two methods: a dynamic organ culture (DOC) incubator and a well-plate (WP) system.4.?Tissue viability, assessed through both structural and functional markers, was preserved throughout 12?h of incubation. ABZ was metabolized to its (+) and (-) albendazole sulfoxide stereoisomers (ABZSO) in bovine PCLS. The interaction between ABZ and MTZ resulted in a reduction (p?0.001) in the rates of appearance of (+) ABZSO. Conversely, in presence of MTZ, the rates of appearance of (?) ABZSO increased under both systems (p?0.05).5.?Both culture systems were suitable for assessing the interaction between ABZ and MTZ.6.?Overall, the results presented herein show that PCLS are a useful and reliable tool for short-term studies on metabolic drug–drug interactions in the bovine species. 相似文献
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《Transboundary and Emerging Diseases》2018,65(4):976-982
Neosporosis, caused by the protozoan Neospora caninum , is a major cause of reproductive failure in ruminants causing enormous economic losses. The objective of this study was to estimate the infection rate and molecular identification of N. caninum in Tunisian cattle and sheep. A total number of 348 meat samples were collected from 150 cows and 198 ewes slaughtered in the regional slaughterhouse of Béja (North‐west Tunisia) and tested for the presence of N. caninum ITS 1 gene using PCR followed by sequencing of some PCR products. A phylogenetic tree was then constructed to compare the partial sequences of the ITS 1 gene with GenBank sequences. The overall molecular infection prevalence of N. caninum was significantly higher in cattle than in sheep (22 and 10.6%, respectively, p = .003). In sheep, the highest prevalence was observed in the northern Béja locality (31.2 ± 16.1), with the Noire de Thibar breed as the most infected sheep breed (31.7 ± 14.2%) (p < .001). In cattle, there were no differences in the molecular prevalence of N. caninum according to breeds and localities. The association between age and N. caninum molecular prevalence was statistically significant in both species; the highest prevalence was observed in sheep of more than one year of age (19.4 ± 9.1%), and in cattle between two and eight years of age (28.8 ± 10.9%). Comparison of the partial sequences of the ITS 1 gene revealed 96%–100% similarity among our N. caninum amplicon and those deposited in GenBank. To our knowledge, this is the first detection and molecular identification of N. caninum in sheep and cattle in North Africa. This information is pertinent in designing control programmes that would reduce economic losses in the livestock industry. 相似文献
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目的调查天津市周边区县奶牛隐孢子虫感染情况。方法对5处奶牛粪样进行检查,采用改良抗酸染色法初筛,对检出的可疑阳性样本采用金胺-酚染色、金胺酚-改良抗酸染色、蔗糖不连续梯度离心法及饱和硫酸锌漂浮等方法进一步观察确定。结果个体养殖户奶牛粪检隐孢子虫阳性率西青区为8.33%(3/36),东丽区为70.00%(7/10),津南区为6.67%(1/15)。中型奶牛场奶牛粪样75份,其中武清县35份,蓟县40份,均为阴性。检出的隐孢子虫经初步鉴定分别为鼠隐孢子虫与微小隐孢子虫。结论天津地区奶牛有一定程度的隐孢子虫感染,需进一步加强小型养牛户的卫生防疫。 相似文献