全文获取类型
收费全文 | 1798篇 |
免费 | 118篇 |
国内免费 | 8篇 |
专业分类
耳鼻咽喉 | 11篇 |
儿科学 | 29篇 |
妇产科学 | 17篇 |
基础医学 | 164篇 |
口腔科学 | 27篇 |
临床医学 | 139篇 |
内科学 | 562篇 |
皮肤病学 | 15篇 |
神经病学 | 145篇 |
特种医学 | 43篇 |
外科学 | 298篇 |
综合类 | 43篇 |
一般理论 | 2篇 |
预防医学 | 170篇 |
眼科学 | 47篇 |
药学 | 64篇 |
中国医学 | 2篇 |
肿瘤学 | 146篇 |
出版年
2022年 | 17篇 |
2021年 | 29篇 |
2020年 | 27篇 |
2019年 | 35篇 |
2018年 | 36篇 |
2017年 | 28篇 |
2016年 | 38篇 |
2015年 | 41篇 |
2014年 | 49篇 |
2013年 | 82篇 |
2012年 | 96篇 |
2011年 | 102篇 |
2010年 | 50篇 |
2009年 | 50篇 |
2008年 | 116篇 |
2007年 | 101篇 |
2006年 | 102篇 |
2005年 | 98篇 |
2004年 | 80篇 |
2003年 | 96篇 |
2002年 | 103篇 |
2001年 | 44篇 |
2000年 | 40篇 |
1999年 | 39篇 |
1998年 | 14篇 |
1997年 | 18篇 |
1996年 | 17篇 |
1995年 | 18篇 |
1994年 | 13篇 |
1993年 | 11篇 |
1992年 | 21篇 |
1991年 | 12篇 |
1990年 | 20篇 |
1989年 | 17篇 |
1988年 | 18篇 |
1987年 | 13篇 |
1986年 | 23篇 |
1985年 | 18篇 |
1984年 | 15篇 |
1983年 | 16篇 |
1982年 | 13篇 |
1981年 | 14篇 |
1980年 | 6篇 |
1979年 | 8篇 |
1978年 | 7篇 |
1976年 | 6篇 |
1974年 | 10篇 |
1972年 | 8篇 |
1969年 | 6篇 |
1968年 | 13篇 |
排序方式: 共有1924条查询结果,搜索用时 281 毫秒
31.
32.
Helicobacter pylori and the prevention of gastric cancer. 总被引:2,自引:0,他引:2
Terrence Sullivan Fredrick D Ashbury Carlo A Fallone Farah Naja Richard Schabas Philip C Hébert Richard Hunt Nicola Jones 《Journal canadien de gastroenterologie》2004,18(5):295-302
BACKGROUND: Helicobacter pylori is an important cause of stomach cancer that infects a substantial proportion of the Canadian adult population. H pylori can be detected by noninvasive tests and effectively eradicated by medical treatment. Screening for and treatment of H pylori may represent a significant opportunity for preventive oncology. METHODS: Cancer Care Ontario organized a workshop held in Toronto, Ontario, on October 24 and 25, 2002, to: review the current state of knowledge regarding H pylori treatment and cancer prevention; determine if there is currently sufficient evidence to consider the promotion of H pylori treatment for the purpose of cancer prevention; identify critical areas for research; and advise Cancer Care Ontario on H pylori and cancer prevention. RESULTS: Workshop participants developed a number of recommendations for research into the relationship between H pylori and stomach cancer, including determining the prevalence of infection in different regions of Canada, the pathogenetic sequence of carcinogenesis from H pylori infection, and the implementation of a prospective observational study. INTERPRETATION: Although the rate of H pylori infection is declining in Canada and the treatment of H pylori is generally accepted to be safe, the evidence to date may not warrant the implementation of population screening for H pylori infection to prevent gastric carcinoma in average-risk populations. Rather, a demonstration project is needed to estimate prevalence, evaluate the merits of screening, measure patient compliance and physician participation, develop education materials, establish a registry for monitoring and evaluation, and develop a quality assurance framework. 相似文献
33.
34.
Carr A Chuah J Hudson J French M Hoy J Law M Sayer D Emery S Cooper DA 《AIDS (London, England)》2000,14(9):1171-1180
BACKGROUND: Highly active antiretroviral therapy (HAART) including two nucleoside analogues and a potent protease inhibitor is standard of care initial therapy for HIV-infected adults. The best-tolerated and most potent initial HAART regimen is unknown and was investigated in this study. METHODS: One hundred and nine HIV-infected adults with no prior antiretroviral therapy, and CD4 lymphocyte counts < 500 x 10(6) cells/l or plasma HIV RNA > 30,000 copies/ml were randomized to zidovudine-lamivudine-indinavir (ZDV-3TC-IDV), stavudine-lamivudine-indinavir (d4T-3TC-IDV) or stavudine-didanosine-indinavir (d4T-ddI-IDV) for 52 weeks. The primary endpoints were plasma HIV RNA and drug-related adverse events. Other assessments were overall safety, adherence and adverse events, CD4 lymphocyte counts, cutaneous delayed type hypersensitivity (DTH) responses and quality of life (Euroqol). RESULTS: Only 58% patients had HIV RNA < 50 copies/ml plasma at 12 months, with no significant difference between the three regimes (P = 0.34). Drug-related adverse events sufficiently severe to warrant drug discontinuation were less common (P = 0.06) in patients receiving d4T-3TC-IDV (18%) than in those receiving ZDV-3TC-IDV (34%) or d4T-ddI-IDV (41%). The percentages of patients who remained on their assigned therapy with plasma HIV RNA < 50 copies/ml at 52 weeks were 60% with d4T-3TC-IDV, 53% with ZDV-3TC-IDV and 35% with d4T-ddI-IDV. Virological failure at 52 weeks was more likely in those whose adherence was estimated to be < 100% in the first 4 weeks of therapy (P = 0.02), but not in those who developed grade 3 or 4 drug-related adverse events. At 52 weeks, the mean CD4 lymphocyte count increase was 200 x 10(6) cells/l with only 7% of patients having counts lower than at baseline; DTH responses improved but remained clinically impaired in most patients. Quality of life improved significantly in all groups. CONCLUSIONS: Initial HAART regimens including IDV failed to suppress plasma HIV RNA to < 50 copies/ml in > 40% patients after only 12 months of therapy although there was significant overall improvement immunologically and in quality of life. The type of dual nucleoside combination used was less important in predicting virological failure than was imperfect adherence early in therapy. Consideration should be given to modifying a HAART regimen relatively early in non-adherent patients. 相似文献
35.
Baughman RP Koehler A Bejarano PA Lower EE Weber FL 《Archives of internal medicine》2003,163(5):615-620
BACKGROUND: Methotrexate has become a standard second-line agent for the treatment of sarcoidosis. Because sarcoidosis has a high frequency of liver involvement, we routinely perform a liver biopsy after each cumulative gram of methotrexate therapy in patients with sarcoidosis in whom we plan to continue therapy. METHODS: Following a previously described protocol for methotrexate therapy, we have performed 100 liver biopsies on 68 patients with chronic sarcoidosis at our institution. On the basis of the liver biopsy results, we identified the following 4 groups: sarcoidosis (47 cases), toxic effects of methotrexate (14 cases), hepatitis C (2 cases), and normal liver tissue (37 cases). RESULTS: We found no difference among the groups in terms of age, weight at time of biopsy, the number of patients receiving corticosteroids at the time of biopsy, cumulative dose of methotrexate, race, or sex. The 14 cases of toxic reactions to methotrexate included 5 patients who had undergone 1 or more previous liver biopsies in which the results did not show toxic effects. We found a significant difference between groups for levels of alkaline phosphatase and asparate aminotransferase at the time of starting (or restarting) methotrexate therapy (analysis of variance, P<.05). This finding was also true for the liver function tests performed at the time of the biopsy (analysis of variance, P<.05). The highest values were for those whose biopsy findings showed sarcoidosis. CONCLUSIONS: Toxic reactions to methotrexate eventually occurred in more than 10% of patients with sarcoidosis treated for more than 2 years with methotrexate. Because of hepatic involvement owing to sarcoidosis, results of serial liver function tests were not useful in determining which patients would have this reaction to methotrexate. 相似文献
36.
Merkel PA Herlyn K Martin RW Anderson JJ Mayes MD Bell P Korn JH Simms RW Csuka ME Medsger TA Rothfield NF Ellman MH Collier DH Weinstein A Furst DE Jiménez SA White B Seibold JR Wigley FM;Scleroderma Clinical Trials Consortium 《Arthritis and rheumatism》2002,46(9):2410-2420
OBJECTIVE: To document disease activity and functional status in patients with scleroderma (systemic sclerosis [SSc]) and Raynaud's phenomenon (RP) and to determine the sensitivity to change, reliability, ease of use, and validity of various outcome measures in these patients. METHODS: Patients with SSc and moderate-to-severe RP participating in a multicenter RP treatment trial completed daily diaries documenting the frequency and duration of RP attacks and recorded a daily Raynaud's Condition Score (RCS). Mean scores for the 2-week periods prior to baseline (week 0), end of trial (week 6), and posttrial followup (week 12) were calculated. At weeks 0, 6, and 12, physicians completed 3 global assessment scales and performed clinical assessments of digital ulcers and infarcts; patients completed the Health Assessment Questionnaire (HAQ), the Arthritis Impact Measurement Scales 2 (AIMS2) mood and tension subscales, 5 specific SSc/RP-related visual analog scales (VAS), and 3 other VAS global assessments. We used these measures to document baseline disease activity and to assess their construct validity, sensitivity to change, and reliability in trial data. RESULTS: Two hundred eighty-one patients (248 women, 33 men; mean age 50.4 years [range 18-82 years]) from 14 centers participated. Forty-eight percent had limited cutaneous SSc; 52% had diffuse cutaneous SSc. Fifty-nine patients (21%) had digital ulcers at baseline. Patients had 3.89 +/- 2.33 (mean +/- SD) daily RP attacks (range 0.8-14.6), with a duration of 82.1 +/- 91.6 minutes/attack. RCS for RP activity (possible range 0-10) was 4.30 +/- 1.92. HAQ scores (0-3 scale) indicated substantial disability at baseline (total disability 0.86, pain 1.19), especially among the subscales pertaining to hand function (grip, eating, dressing). AIMS2 mood and tension scores were fairly high, as were many of the VAS scores. Patients with digital ulcers had worse RCS, pain, HAQ disability (overall, grip, eating, and dressing), physician's global assessment, and tension, but no significant difference in the frequency of RP, duration of RP, patient's global assessment, or mood, compared with patients without digital ulcers. VAS scores for digital ulcers as rated by the patients were not consistent with the physician's ratings. Factor analysis of the 18 measures showed strong associations among variables in 4 distinct domains: disease activity, RP measures, digital ulcer measures, and mood/tension. Reliability of the RCS, HAQ pain and disability scales, and AIMS2 mood and tension subscales was high. The RP measures demonstrated good sensitivity to change (effect sizes 0.33-0.76). CONCLUSION: Our findings demonstrate that the significant activity, disability, pain, and psychological impact of RP and digital ulcers in SSc can be measured by a small set of valid and reliable outcome measures. These outcome measures provide information beyond the quantitative metrics of RP attacks. We propose a core set of measures for use in clinical trials of RP in SSc patients that includes the RCS, patient and physician VAS ratings of RP activity, a digital ulcer/infarct measure, measures of disability and pain (HAQ), and measures of psychological function (AIMS2). 相似文献
37.
Ramnath Santosh Ramanathan Dolora Wisco Daniel Vela-Duarte Atif Zafar Ather Taqui Stacey Winners A Blake Buletko Fredrick Hustey Andrew Reimer Andrew Russman Ken Uchino M Shazam Hussain 《Journal of stroke and cerebrovascular diseases》2021,30(7):105801
ObjectivesMobile stroke unit (MSU) has been shown to rapidly provide pre-hospital thrombolysis in acute ischemic stroke (AIS). MSU encounters neurological disorders other than AIS that require emergent treatment.Methods/MaterialsWe obtained pre-hospital diagnosis and treatment data from the prospectively collected dataset on 221 consecutive MSU encounters. Based on initial clinical evaluation and neuroimaging obtained on MSU, the diagnosis of AIS (definite, probable, and possible AIS, transient ischemic attack), intracranial hemorrhage, and likely stroke mimics was made.ResultsFrom July 2014 to April 2015, 221 patients were treated on MSU. 78 (35%) patients had initial clinical diagnosis of definite/probable AIS or TIA, 69 (31%) were diagnosed as possible AIS or TIA, 15 (7%) had intracranial hemorrhage while 59 patients (27%) were diagnosed as likely stroke mimics. Stroke mimics encountered included 13 (6%) metabolic encephalopathy, 11 (5%) seizures, 9 (4%) migraines, 3 (1%) substance abuse, 2 (1%) CNS tumor, 3 (1%) infectious etiology and 3 (1%) hypoglycemia. Fifty-four (24%) patients received non-thrombolytic treatments on MSUConclusionAbout one third of MSU encounters were not AIS initially, including intracranial hemorrhage and stroke mimics. MSU can be utilized to provide pre-hospital treatments in emergent neurological conditions other than AIS. 相似文献
38.
39.
Notch signaling is a potent inducer of growth arrest and apoptosis in a wide range of B-cell malignancies 总被引:12,自引:0,他引:12
下载免费PDF全文
![点击此处可从《Blood》网站下载免费的PDF全文](/ch/ext_images/free.gif)
Zweidler-McKay PA He Y Xu L Rodriguez CG Karnell FG Carpenter AC Aster JC Allman D Pear WS 《Blood》2005,106(12):3898-3906
40.