全文获取类型
收费全文 | 6413篇 |
免费 | 349篇 |
国内免费 | 11篇 |
专业分类
耳鼻咽喉 | 52篇 |
儿科学 | 288篇 |
妇产科学 | 85篇 |
基础医学 | 544篇 |
口腔科学 | 162篇 |
临床医学 | 439篇 |
内科学 | 1415篇 |
皮肤病学 | 97篇 |
神经病学 | 449篇 |
特种医学 | 169篇 |
外科学 | 1491篇 |
综合类 | 165篇 |
一般理论 | 1篇 |
预防医学 | 223篇 |
眼科学 | 264篇 |
药学 | 394篇 |
中国医学 | 24篇 |
肿瘤学 | 511篇 |
出版年
2023年 | 66篇 |
2022年 | 113篇 |
2021年 | 306篇 |
2020年 | 125篇 |
2019年 | 188篇 |
2018年 | 235篇 |
2017年 | 177篇 |
2016年 | 215篇 |
2015年 | 211篇 |
2014年 | 286篇 |
2013年 | 380篇 |
2012年 | 537篇 |
2011年 | 521篇 |
2010年 | 326篇 |
2009年 | 251篇 |
2008年 | 348篇 |
2007年 | 359篇 |
2006年 | 266篇 |
2005年 | 313篇 |
2004年 | 285篇 |
2003年 | 239篇 |
2002年 | 179篇 |
2001年 | 117篇 |
2000年 | 86篇 |
1999年 | 76篇 |
1998年 | 49篇 |
1997年 | 43篇 |
1996年 | 28篇 |
1995年 | 28篇 |
1994年 | 22篇 |
1993年 | 12篇 |
1992年 | 38篇 |
1991年 | 36篇 |
1990年 | 27篇 |
1989年 | 35篇 |
1988年 | 28篇 |
1987年 | 19篇 |
1986年 | 16篇 |
1985年 | 26篇 |
1984年 | 19篇 |
1983年 | 15篇 |
1982年 | 8篇 |
1981年 | 7篇 |
1980年 | 13篇 |
1979年 | 9篇 |
1978年 | 9篇 |
1976年 | 9篇 |
1974年 | 15篇 |
1973年 | 7篇 |
1972年 | 9篇 |
排序方式: 共有6773条查询结果,搜索用时 15 毫秒
31.
Renal involvement as the first manifestation of sarcoidosis is rare and has never been reported in India. This report describes a 35 year old man who was admitted to the emergency department with a clinical diagnosis of acute on chronic renal failure, secondary to obstructive uropathy. Postmortem examination unexpectedly revealed disseminated sarcoidosis. 相似文献
32.
33.
Multilocus short sequence repeat sequencing approach for differentiating among Mycobacterium avium subsp. paratuberculosis strains
下载免费PDF全文
![点击此处可从《Journal of clinical microbiology》网站下载免费的PDF全文](/ch/ext_images/free.gif)
Amonsin A Li LL Zhang Q Bannantine JP Motiwala AS Sreevatsan S Kapur V 《Journal of clinical microbiology》2004,42(4):1694-1702
We describe a multilocus short sequence repeat (MLSSR) sequencing approach for the genotyping of Mycobacterium avium subsp. paratuberculosis (M. paratuberculosis) strains. Preliminary analysis identified 185 mono-, di-, and trinucleotide repeat sequences dispersed throughout the M. paratuberculosis genome, of which 78 were perfect repeats. Comparative nucleotide sequencing of the 78 loci of six M. paratuberculosis isolates from different host species and geographic locations identified a subset of 11 polymorphic short sequence repeats (SSRs), with an average of 3.2 alleles per locus. Comparative sequencing of these 11 loci was used to genotype a collection of 33 M. paratuberculosis isolates representing different multiplex PCR for IS900 loci (MPIL) or amplified fragment length polymorphism (AFLP) types. The analysis differentiated the 33 M. paratuberculosis isolates into 20 distinct MLSSR types, consistent with geographic and epidemiologic correlates and with an index of discrimination of 0.96. MLSSR analysis was also clearly able to distinguish between sheep and cattle isolates of M. paratuberculosis and easily and reproducibly differentiated strains representing the predominant MPIL genotype (genotype A18) and AFLP genotypes (genotypes Z1 and Z2) of M. paratuberculosis described previously. Taken together, the results of our studies suggest that MLSSR sequencing enables facile and reproducible high-resolution subtyping of M. paratuberculosis isolates for molecular epidemiologic and population genetic analyses. 相似文献
34.
Repetitive sequence-based PCR (rep-PCR) and amplified fragment length polymorphism (AFLP) were used to characterize a sample of 43 field isolates and 4 attenuated vaccine strains of Pasteurella multocida recovered from multiple avian species. Both rep-PCR and AFLP assays were rapid and reproducible, with high indices of discrimination. Concordance analyses of rep-PCR and AFLP with somatic serotyping indicate that, in general, somatic serotyping is a poor indicator of genetic relatedness among isolates of P. multocida. In addition, the data provide evidence of host specificity of P. multocida clones. Overall, the results of our study indicate that the rep-PCR and AFLP techniques enable rapid fingerprinting of P. multocida isolates from multiple avian species and enhance the investigation of fowl cholera outbreaks. 相似文献
35.
Molecular epidemiology of Mycobacterium avium subsp. paratuberculosis isolates recovered from wild animal species
下载免费PDF全文
![点击此处可从《Journal of clinical microbiology》网站下载免费的PDF全文](/ch/ext_images/free.gif)
Motiwala AS Amonsin A Strother M Manning EJ Kapur V Sreevatsan S 《Journal of clinical microbiology》2004,42(4):1703-1712
Mycobacterial isolates were obtained by radiometric culture from 33 different species of captive or free-ranging animals (n = 106) and environmental sources (n = 3) from six geographic zones within the United States. The identities of all 109 isolates were confirmed by using mycobactin J dependence and characterization of five well-defined molecular markers, including two integration loci of IS900 (loci L1 and L9), one Mycobacterium avium subsp. paratuberculosis (M. paratuberculosis)-specific sequence (locus 251), and one M. avium subsp. avium-specific marker (IS1245), as well as hsp65 and IS1311 restriction endonuclease analyses. Seventy-six acid-fast isolates were identified as M. paratuberculosis, 15 were identified as belonging to the M. avium-M. intracellulare complex (but not M. paratuberculosis), and the remaining 18 were identified as mycobacteria outside the M. avium-M. intracellulare complex. Fingerprinting by multiplex PCR for IS900 integration loci clustered 67 of the 76 M. paratuberculosis strains into a single clade (designated clade A18) and had a Simpson's diversity index (D) of 0.53. In contrast, sequence-based characterization of a recently identified M. paratuberculosis short sequence repeat (SSR) region enabled the differentiation of the M. paratuberculosis isolates in clade A18 into seven distinct alleles (D = 0.75). The analysis revealed eight subtypes among the 33 species of animals, suggesting the interspecies transmission of specific strains. Taken together, the results of our analyses demonstrate that SSR analysis enables the genetic characterization of M. paratuberculosis isolates from different host species and provide evidence for the host specificity of some M. paratuberculosis strains as well as sharing of strains between wild and domesticated animal species. 相似文献
36.
Popat KC Leary Swan EE Mukhatyar V Chatvanichkul KI Mor GK Grimes CA Desai TA 《Biomaterials》2005,26(22):4516-4522
A major goal of bone tissue engineering is to design better scaffold configuration and materials to better control osteoblast behavior. Nanoporous architecture has been shown to significantly affect cellular response. In this work, nanoporous alumina membranes were fabricated by a two-step anodization method to investigate bone cell response. Osteoblasts were seeded on nanoporous alumina membranes to investigate both short-term adhesion and proliferation and long-term functionality and matrix production. Cell adhesion and proliferation were characterized using a standard MTT assay and cell counting. The total protein content was measured after cell lysis using the BCA assay. Matrix production was characterized in terms of surface concentrations of calcium and phosphorous, components of bone matrix, using X-ray photoelectron spectroscopy (XPS). The results from nanoporous alumina membranes were compared with those of amorphous alumina, aluminum, commercially available ANOPORE and glass. Results indicate improved osteoblast adhesion and proliferation and increased matrix production after 4 weeks of study. 相似文献
37.
38.
Vivek Roy Waleska S Pérez Mary Eapen Judith C W Marsh Marcelo Pasquini Ricardo Pasquini Mahmoud M Mustafa Christopher N Bredeson 《Biology of blood and marrow transplantation》2005,11(8):600-608
Patients with Diamond-Blackfan anemia (DBA) who are unresponsive to or intolerant of corticosteroids, experience treatment failure with other treatments, develop additional cytopenias or clonal disease, or opt for curative therapy are often treated with allogeneic bone marrow transplantation. We studied the transplantation outcomes of 61 DBA patients whose data were reported to the International Bone Marrow Transplant Registry between 1984 and 2000. The median age was 7 years (range, 1-32 years). Among 55 patients with available transfusion information, 35 (64%) had received > or =20 units of blood before transplantation. Most patients (67%) received their bone marrow grafts from an HLA-matched related donor. The median time to neutrophil recovery was 17 days (range, 10-119 days) and to platelet recovery was 23 days (range, 9-119 days). Five patients did not achieve neutrophil engraftment. The 100-day mortality was 18% (95% confidence interval, 10%-29%). Grade II to IV acute graft-versus-host disease occurred in 28% (range, 17%-39%) and chronic graft-versus-host disease in 26% (range, 15%-39%). The 3-year probability of overall survival was 64% (range, 50%-74%). In univariate analysis, a Karnofsky score > or =90 and transplantation from an HLA-identical sibling donor were associated with better survival. These data suggest that allogeneic bone marrow transplantation is effective for the treatment of DBA. Transplantation before deterioration of the performance status and from an HLA-identical sibling donor may improve survival. 相似文献
39.
40.
Raina V Sharma A Deo SV Shukla NK Mohanty BK Goel A Rath GK 《The Journal of the Association of Physicians of India》1998,46(11):926-929
Results of primary surgery with or without locoregional radiotherapy (LRRT) are poor in stage III (T4b, NO-2, M0) breast cancer. Combination of mitoxantrone, mitomycin-c and methotrexate (MMM) has been reported to be as efficacious as doxorubicin based protocols with advantages of reduced nausea, vomiting, alopecia and cardiotoxicity. We tested MMM chemotherapy with LRRT and surgery in locally advanced breast cancer (LABC) with a view to assess response, survival, breast conservation, cost and toxicity. Fifty two previously untreated patients were given Mitoxantrone: 8 mg/m sq by infusion on days 1 and 21, Mitomycin-C: 8 mg/m sq by infusion on day 1 and Methotrexate: 35 mg/m sq i.v. on days 1 and 21. Cycles were repeated every 42 days. After 3 cycles LRRT was given if lump reduced to less than 2 cms. Otherwise patients were subjected to modified radical mastectomy (MRM) or radical mastectomy (RM). Following this 3 more cycles of chemotherapy were given. Patients with soft tissue, skin or heavy nodal involvement also received LRRT. Tamoxifen 20 mg daily was prescribed at the end of chemotherapy to postmenopausal patients. Complete/partial responses were seen in 5 and 26 patients, respectively after chemotherapy giving an overall response of 59.5%. Twenty four patients each had LRRT and MRM/RM. Responses could be significantly enhanced by LRRT/and or surgery. Nineteen out of 25 relapses were at distant sites. Breast conservation was achieved in 24/52 (46%) patients. Three year disease free and overall survival was 54% and 65%, respectively. There was 1 toxic death. Severe prolonged myelosuppresion was seen in those who also received LRRT. Mucositis, alopecia, nausea and vomiting were minor problems. Overall, combination was less expensive than doxorubicin based protocols. 相似文献