全文获取类型
收费全文 | 3696篇 |
免费 | 198篇 |
国内免费 | 15篇 |
专业分类
耳鼻咽喉 | 68篇 |
儿科学 | 41篇 |
妇产科学 | 36篇 |
基础医学 | 395篇 |
口腔科学 | 83篇 |
临床医学 | 324篇 |
内科学 | 854篇 |
皮肤病学 | 205篇 |
神经病学 | 309篇 |
特种医学 | 120篇 |
外科学 | 650篇 |
综合类 | 14篇 |
一般理论 | 2篇 |
预防医学 | 239篇 |
眼科学 | 114篇 |
药学 | 146篇 |
中国医学 | 2篇 |
肿瘤学 | 307篇 |
出版年
2023年 | 17篇 |
2022年 | 50篇 |
2021年 | 101篇 |
2020年 | 48篇 |
2019年 | 85篇 |
2018年 | 106篇 |
2017年 | 68篇 |
2016年 | 75篇 |
2015年 | 108篇 |
2014年 | 132篇 |
2013年 | 194篇 |
2012年 | 282篇 |
2011年 | 251篇 |
2010年 | 147篇 |
2009年 | 153篇 |
2008年 | 232篇 |
2007年 | 249篇 |
2006年 | 232篇 |
2005年 | 205篇 |
2004年 | 191篇 |
2003年 | 160篇 |
2002年 | 154篇 |
2001年 | 34篇 |
2000年 | 44篇 |
1999年 | 43篇 |
1998年 | 32篇 |
1997年 | 33篇 |
1996年 | 31篇 |
1995年 | 28篇 |
1994年 | 27篇 |
1993年 | 33篇 |
1992年 | 30篇 |
1991年 | 39篇 |
1990年 | 28篇 |
1989年 | 16篇 |
1988年 | 24篇 |
1987年 | 15篇 |
1986年 | 20篇 |
1985年 | 13篇 |
1984年 | 17篇 |
1983年 | 16篇 |
1982年 | 13篇 |
1981年 | 15篇 |
1980年 | 7篇 |
1978年 | 9篇 |
1977年 | 10篇 |
1976年 | 8篇 |
1975年 | 12篇 |
1973年 | 8篇 |
1932年 | 7篇 |
排序方式: 共有3909条查询结果,搜索用时 15 毫秒
31.
Ramon Sanchez Richard K. Sibley Juan Rosai Ronald F. Dorfman 《Ultrastructural pathology》1981,2(2):101-119
Eleven cases of sinus histiocytosis with massive lymphadenopathy (SHML) involving lymph nodes were studied electron microscopically. Histiocytes were the most conspicuous element of the infiltrate. They could be divided into small and large forms, although transitions were apparent among them. Most of the small histiocytes were located in the medullary cords. The large histiocytes were predominantly seen within sinuses and were subdivided into two types on the basis of their appearance. The most distinctive feature of these histiocytes was the presence of lymphocytes, plasma cells, and neutrophils within their cytoplasm. Other cells present in the infiltrate were lymphocytes, plasma cells, and occasional neutrophils and mast cells. Blood vessels were prominent throughout. Virus particles, bacteria, and Langerhans granules were consistently absent. No morphologic clues were provided by this study as to the etiology of this disorder. 相似文献
32.
Enhanced viral clearance in interleukin-18 gene-deficient mice after pulmonary infection with influenza A virus 总被引:3,自引:0,他引:3
Van Der Sluijs KF Van Elden LJ Arens R Nijhuis M Schuurman R Florquin S Kwakkel J Akira S Jansen HM Lutter R Van Der Polls T 《Immunology》2005,114(1):112-120
T helper 1 driven immune responses facilitate host defence during viral infections. Because interleukin-18 (IL-18) mediates T helper 1 driven immune responses, and since mature IL-18 is up-regulated in human macrophages after influenza virus infection in vitro, it has been suggested that IL-18 plays an important role in the immune response to influenza. To determine the role of IL-18 in respiratory tract infection with influenza, IL-18 gene-deficient (IL-18(-/-)) and normal wildtype mice were intranasally inoculated with influenza A virus. Influenza resulted in an increase in constitutively expressed IL-18 in the lungs of wildtype mice. The clearance of influenza A was inhibited by IL-18, as indicated by reduced viral loads on day 8 and day 12 after infection in IL-18(-/-) mice. This enhanced viral clearance correlated with increased CD4(+) T-cell activation in the lungs as reflected by CD69 expression on the cell surface. Surprisingly, interferon-gamma (IFN-gamma) levels were similar in the lungs of IL-18(-/-) mice and wildtype mice. Intracellular IFN-gamma staining revealed similar expression levels in lung-derived natural killer cells, CD4(+) and CD8(+) T cells, indicating that IFN-gamma production is IL-18-independent during influenza virus infection. Tumour necrosis factor-alpha production by CD4(+) T cells was significantly lower in IL-18(-/-) mice than in wildtype mice. Our data indicate that endogenous IL-18 impairs viral clearance during influenza A infection. 相似文献
33.
Allcock RJ Windsor L Gut IG Kucharzak R Sobre L Lechner D Garnier JG Baltic S Christiansen FT Price P 《Human mutation》2004,24(6):517-525
The region spanning the tumor necrosis factor (TNF) cluster in the human major histocompatibility complex (MHC) has been implicated in susceptibility to numerous immunopathological diseases, including type 1 diabetes mellitus and rheumatoid arthritis. However, strong linkage disequilibrium across the MHC has hampered the identification of the precise genes involved. In addition, the observation of "blocks" of DNA in the MHC within which recombination is very rare, limits the resolution that may be obtained by genotyping individual SNPs. Hence a greater understanding of the haplotypes of the block spanning the TNF cluster is necessary. To this end, we genotyped 32 human leukocyte antigen (HLA)-homozygous workshop cell lines and 300 healthy control samples for 19 coding and promoter region SNPs spanning 45 kb in the central MHC near the TNF genes. The workshop cell lines defined 11 SNP haplotypes that account for approximately 80% of the haplotypes observed in the 300 control individuals. Using the control individuals, we defined a further six haplotypes that account for an additional 10% of donors. We show that the 17 haplotypes of the "TNF block" can be identified using 15 SNPs. 相似文献
34.
Daniela de Queiroz Moura Ramon Rawache Marília Ferreira Gomes Garcia Nathalia Farias Vasconcelos Priscila Santos Gustavo Rego Coelho Thiago Luis da Paz Santos Duílio Reis da Rocha Filho Sonia Leite da Silva Eliana Regia Barbosa de Almeida Paula F.C.B.C. Fernandes João Batista Cerqueira José Huygens Parente Garcia Claudia Maria Costa de Oliveira 《Transplantation proceedings》2021,53(4):1345-1349
Transplantation of any organ has some inherent risk of disease transmission, such as infection and malignancy. The present study aims to describe 2 cases of choriocarcinoma transmission after kidney and liver transplantation originating from the same patient. The donor was a 17-year-old woman who died of cerebral hemorrhage. Both organ recipients died of metastatic choriocarcinoma few months after the transplantation, within days after starting chemotherapy. Retrospective hCG (human chorionic gonadotropin hormone) analysis in donor's blood stored at the time of donation had a result of 9324 mIU/mL. Despite its rarity, clinicians should be aware of the risk of transplant-related choriocarcinoma from female donors in childbearing age. In some cases, hCG dosage should be performed before donation. 相似文献
35.
Conclusion Genetic analysis of SLE in the various autoimmune mice has revealed that this disease is multigenic in nature and that several, quite distinct genetic backgrounds are compatible with this disease. Although the nature of these genetic components has not been defined, studies on New Zealand mice have indicated that multiple, unlinked genes are responsible for the expression of various disease manifestations and the production of autoantibodies. However, it is significant that single gene mutations, such as lpr, gld and Yaa, markedly influence the development of the lupus-like autoimmune syndrome. In addition, it is becoming clear, based on the results obtained from H-2 congenic mice, that the MHC class II genes play a crucial role in the development of SLE. However, the absence of severe autoimmune pathology in mice lacking the SLE background, even in the presence of the single autoimmune mutant gene and of the appropriate MHC class II genes, clearly indicates the requirement of supplementary genetic abnormalities for the fullblown manifestations of SLE.Although the abnormality of the lpr and possibly gld mutation is associated with the molecules mediating the apoptosis, the nature of the Yaa gene defect has not yet been identified. The differences in autoimmune accelerating effects between the Yaa gene and the lpr gene on autoimmune-prone and non-autoimmune mice strongly suggest that the molecular defect of the Yaa gene is likely to differ from those of the lpr and gld genes. We propose that the Yaa gene effect may result from the expression of the Yaa gene-related molecule on B cells. This molecule could behave as an intercellular adhesion-like molecule, thereby facilitating the interaction and subsequent activation of autoreactive T and B cells. Alternatively, the Yaa molecule-derived peptide could be efficiently presented in the context of MHC class II antigens by B cells, and its recognition by Yaa-specific T helper cells could activate autoantigen-specific B cells even in the absence of autoantigen-specific T helper cells. Obviously, the molecular identification of the Yaa gene product would be of paramount importance in helping answer this important and interesting question. 相似文献
36.
Ramon Pathi Michael Sage John Slavotinek Ahmad Hanieh 《Journal of Medical Imaging and Radiation Oncology》2004,48(1):61-63
A case of an abdominal cerebrospinal fluid (CSF) pseudocyst in a patient with a ventriculoperitoneal shunt is reported to illustrate this known but rare complication. In the setting of a VP shunt, the frequency of abdominal CSF pseudocyst formation is approximately 3.2%, often being precipitated by a recent inflammatory or infective process or recent surgery. Larger pseudocysts tend to be sterile, whereas smaller pseudocysts are more often infected. Ultrasound and CT each have characteristic findings. 相似文献
37.
Preoperative uracil, tegafur, and concomitant radiotherapy in operable rectal cancer: a phase II multicenter study with 3 years' follow-Up. 总被引:2,自引:0,他引:2
Carlos Fernández-Martos Jorge Aparicio Carles Bosch Marilo Torregrosa Juan Manuel Campos Salvador Garcera Jose Maria Vicent Inmaculada Maestu Miguel Angel Climent Jose Luis Mengual Alejandro Tormo Ana Hernandez Rafael Estevan Jose Maria Richart Vicente Viciano Natalia Uribe Jorge Campos Ramon Puchades Francisco Arlandis Daniel Almenar 《Journal of clinical oncology》2004,22(15):3016-3022
PURPOSE: To assess tolerance and efficacy of preoperative treatment with uracil/tegafur and radiotherapy (RT) followed by surgery and postoperative flurouracil (FU)/leucovorin (LV) in patients with rectal cancer. PATIENTS AND METHODS: Patients (n = 94) with potentially resectable tumors, ultrasound at stages T2N+ (n = 4), T3 (n = 77), T4 (n = 13) were treated with UFT (400 mg/m2/d, 5 days a week for 5 weeks) and concomitant RT to the pelvis (45 Gy; 1.8 Gy/d over 5 weeks). Patients underwent surgery 5 to 6 weeks later followed by four cycles of FU/LV. Primary end points included downstaging, pathologic responses, and sphincter-preserving surgery. Secondary end points were recurrence-free survival and overall survival. RESULTS: All patients received the full RT dose. Fifteen patients (16%) needed UFT dose reduction. Preoperative G3+ toxicities included diarrhea (14%), leukopenia (1%), thrombocytopenia (1%), and nausea (4%). The downstaging rate was 54%, pathologic complete response (pCR) was 9% and, in an additional 23%, there were only residual microscopic foci. When cellular viability criteria were taken into account, the pCR was 15%. From 43 patients with abdominoperineal resection indication, 11 (25%) had sphincter-preserving surgery performed. Postoperative scheduled chemotherapy dose was not administered to 24% of patients because of G3+ toxicity (diarrhea, 8%; mucositis, 9%; and leukopenia, 7%). Patients with downstaging had significantly higher survival and recurrence-free survival rates than those without. At 3 years, actuarial patterns of failure were pelvic, 5% and distant, 11%. OS was 75%. CONCLUSION: UFT combined with RT is safe and effective. In resectable rectal cancer, if preoperative treatment is considered, this approach can be an option. 相似文献
38.
Expression profiling of T-cell lymphomas differentiates peripheral and lymphoblastic lymphomas and defines survival related genes. 总被引:1,自引:0,他引:1
Beatriz Martinez-Delgado Barbara Meléndez Marta Cuadros Javier Alvarez Jose Maria Castrillo Ana Ruiz De La Parte Manuela Mollejo Carmen Bellas Ramon Diaz Luis Lombardía Fatima Al-Shahrour Orlando Domínguez Alberto Cascon Mercedes Robledo Carmen Rivas Javier Benitez 《Clinical cancer research》2004,10(15):4971-4982
PURPOSE: T-Cell lymphomas constitute heterogeneous and aggressive tumors in which pathogenic alterations remain largely unknown. Expression profiling has demonstrated to be a useful tool for molecular classification of tumors. EXPERIMENTAL DESIGN: Using DNA microarrays (CNIO-OncoChip) containing 6386 cancer-related genes, we established the expression profiling of T-cell lymphomas and compared them to normal lymphocytes and lymph nodes. RESULTS: We found significant differences between the peripheral and lymphoblastic T-cell lymphomas, which include a deregulation of nuclear factor-kappaB signaling pathway. We also identify differentially expressed genes between peripheral T-cell lymphoma tumors and normal T lymphocytes or reactive lymph nodes, which could represent candidate tumor markers of these lymphomas. Additionally, a close relationship between genes associated to survival and those that differentiate among the stages of disease and responses to therapy was found. CONCLUSIONS: Our results reflect the value of gene expression profiling to gain insight about the molecular alterations involved in the pathogenesis of T-cell lymphomas. 相似文献
39.
Hans Gelderblom Ramon Salazar Jaap Verweij George Pentheroudakis Maja J A de Jonge Martin Devlin Christel van Hooije Francis Seguy Rosendo Obach Joan Pru?onosa Paola Principe Chris Twelves 《Clinical cancer research》2003,9(11):4101-4107
PURPOSE: Diflomotecan (BN80915) is an E-ring modified camptothecin analogue that possesses greater lactone stability in plasma compared with other topoisomerase I inhibitors, a potential advantage for antitumor activity. As with other camptothecins, oral administration has pharmacological and clinical advantages. This Phase I study was performed to assess the feasibility of the administration of oral diflomotecan, to determine the maximum-tolerated, dose its bioavailability, and to explore the pharmacokinetics. EXPERIMENTAL DESIGN: An initial i.v. bolus was administered to assess the bioavailability of diflomotecan. Fourteen days later, diflomotecan was administered p.o. once daily for 5 days to adult patients with solid malignant tumors and repeated every 3 weeks. BN80915 and its open lactone form BN80942 were measured. RESULTS: Twenty-two patients entered the study and received a total of 57 cycles of oral diflomotecan at flat dose levels of 0.10, 0.20, 0.27, and 0.35 mg. The main toxicity was hematological, but some patients experienced alopecia, mild gastrointestinal toxicity, and fatigue. At the 0.35-mg dose level, 2 of 4 patients experienced dose-limiting toxicity comprising grade 3 thrombocytopenia with epistaxis and febrile neutropenia in 1 patient and uncomplicated grade 4 neutropenia lasting for >7 days in another. Toxicity was acceptable at the 0.27-mg dose level at which dose-limiting toxicities were observed in 3 of 12 patients (grade 4 neutropenia > 7 days, complicated by fever in 1 patient but without other signs of infection). After two cycles of diflomotecan, 6 patients had disease stabilization, which was maintained in 2 patients for 9 months and >1 year, respectively. Diflomotecan pharmacokinetics were linear over the dose range studied. Systemic exposure correlated with the fall in WBC counts. The mean oral bioavailability (+/-SD) was 72.24 +/- 59.2% across all dose levels. Urinary excretion of BN80915 was very low. CONCLUSIONS: The recommended oral diflomotecan dose for Phase II studies is 0.27 mg/day x 5 every 3 weeks. This regimen is convenient and generally well tolerated with a favorable pharmacokinetic profile and high but variable bioavailability. 相似文献
40.
Barbara Roa Pauloski Jerilyn A. Logemann Laura A. Colangelo Alfred W. Rademaker Fred M. S. McConnel Mary Anne Heiser Salvatore Cardinale Donald Shedd David Stein Quinter Beery Eugene Myers Jan Lewin Marc Haxer Ramon Esclamado 《The Laryngoscope》1998,108(6):908-916
Postoperative speech function may be influenced by a number of treatment variables. The objective of this study was to examine the relationships among various treatment factors to determine the impact of these measures on speech function. Speech function was tested prospectively in 142 patients with surgically treated oral and oropharyngeal cancer 3 months after treatment. Each patient's speech was recorded during a 6- to 7-minute conversation and while performing a standard articulation test, producing speech outcome measures of percent correct consonant phonemes and percent conversational understandability. Correlational analyses were used to determine the relationships among the speech outcome measures and 14 treatment parameters. Speech function was mildly to moderately negatively correlated with most surgical resection variables, indicating that larger amounts of tissue resected were associated with worse speech function. Overall measures of conversational understandability and percent correct consonant phonemes were related to extent of oral tongue resection, floor of mouth resection, soft palate resection, and total volume of tissue resected. These relationships varied depending on the method of surgical closure. Method of surgical reconstruction had a profound impact on postoperative speech function 3 months after treatment and was an important factor in determining how oral tongue resection influenced articulation and intelligibility. The combination of closure type, percent oral tongue resected, and percent soft palate resected had the strongest relationship with overall speech function for patients with surgically treated oral and oropharyngeal cancer 3 months after treatment. 相似文献