全文获取类型
收费全文 | 1252篇 |
免费 | 66篇 |
专业分类
耳鼻咽喉 | 3篇 |
儿科学 | 35篇 |
妇产科学 | 19篇 |
基础医学 | 182篇 |
口腔科学 | 16篇 |
临床医学 | 141篇 |
内科学 | 247篇 |
皮肤病学 | 11篇 |
神经病学 | 122篇 |
特种医学 | 86篇 |
外科学 | 183篇 |
综合类 | 2篇 |
预防医学 | 30篇 |
眼科学 | 8篇 |
药学 | 113篇 |
中国医学 | 5篇 |
肿瘤学 | 115篇 |
出版年
2023年 | 12篇 |
2022年 | 8篇 |
2021年 | 27篇 |
2020年 | 14篇 |
2019年 | 26篇 |
2018年 | 19篇 |
2017年 | 21篇 |
2016年 | 19篇 |
2015年 | 28篇 |
2014年 | 34篇 |
2013年 | 47篇 |
2012年 | 66篇 |
2011年 | 55篇 |
2010年 | 38篇 |
2009年 | 40篇 |
2008年 | 47篇 |
2007年 | 60篇 |
2006年 | 39篇 |
2005年 | 57篇 |
2004年 | 48篇 |
2003年 | 56篇 |
2002年 | 45篇 |
2001年 | 42篇 |
2000年 | 59篇 |
1999年 | 27篇 |
1998年 | 20篇 |
1997年 | 13篇 |
1996年 | 11篇 |
1995年 | 11篇 |
1994年 | 8篇 |
1993年 | 8篇 |
1992年 | 25篇 |
1991年 | 30篇 |
1990年 | 28篇 |
1989年 | 21篇 |
1988年 | 24篇 |
1987年 | 15篇 |
1986年 | 14篇 |
1985年 | 13篇 |
1984年 | 12篇 |
1983年 | 9篇 |
1981年 | 6篇 |
1979年 | 17篇 |
1976年 | 7篇 |
1975年 | 9篇 |
1974年 | 13篇 |
1973年 | 9篇 |
1972年 | 9篇 |
1971年 | 10篇 |
1967年 | 9篇 |
排序方式: 共有1318条查询结果,搜索用时 21 毫秒
81.
82.
Tricarico M Nunziata C Atzori F Concolino F Macchini V D'Atri S Prete SP Turriziani M Lanzilli G Sera F Abeni D Albanesi V Bonmassar E Pagani E 《Journal of experimental & clinical cancer research : CR》2004,23(4):573-578
A pilot study was conducted to assess the tolerability and the effect on host immunity of a post-surgery adjuvant treatment of melanoma patients with an anti-angiogenic agent, Tamoxifen (TAM, 20 mg/die p.o., daily), combined with immunomodulating cytokines, i.e. recombinant interleukin-2 (IL-2, 4 MUI/m2 s.c., day 8,10,12) and alpha-2b-interferon (IFN, 3 MUI/m2 i.m., day 15,17,19), starting a new cycle on day 21, for a total of 12 cycles. Fifty patients (pts) entered into the study, 27 males and 23 females with a median age of 55 years (range 25-75), performance status (ECOG) 0 with melanoma stage IIA (12 patients), stage IIB (28 patients), stage III (10 patients). Preliminary in vitro studies showed that TAM does not interfere with up-regulation of natural immunity induced by IFN, IL-2, or IFN + IL-2 in normal peripheral blood mononuclear cells (MNC). The clinical study indicates that the protocol was well tolerated. Increase of NK and LAK activity of patient MNC was observed on day 15. The mean disease-free interval was 10 months and 40 pts were alive at 5 years of follow-up. Further investigations should be performed to test effectiveness of this protocol in a randomized study. 相似文献
83.
Filippi M Rocca MA Pagani E Iannucci G Sormani MP Fazekas F Ropele S Hommes OR Comi G 《Archives of neurology》2004,61(9):1409-1412
BACKGROUND: Magnetization transfer magnetic resonance imaging (MT MRI) can provide in vivo markers reflecting the severity of multiple sclerosis-related brain damage occurring within and outside T2-visible lesions. OBJECTIVE: To investigate the effect of intravenous immunoglobulin (IVIG) treatment on the accumulation of brain damage in patients with secondary progressive multiple sclerosis (SPMS), measured using MT MRI.Design, Patients, and Intervention Seventy patients with SPMS participating in the European, multicenter, randomized, double-blind, placebo-controlled trial of IVIG in SPMS underwent brain T2-weighted and MT MRI at baseline and after 12 and 24 months. The MT MRI scans were post-processed and analyzed to obtain MT ratio values from T2-visible lesions and MT ratio histograms from the normal-appearing brain tissue (NABT). RESULTS: At baseline, a significant difference was found for NABT MT ratio histogram peak height (P =.003) between treated patients and patients receiving placebo. No significant differences between treated patients and those receiving placebo were found for any of the considered MT MRI-derived metrics in terms of treatment x time interaction. Nevertheless, over the 24-month period, the placebo patients experienced a 6.75% reduction of the NABT MT ratio histogram peak height, whereas treated patients experienced only a 0.92% reduction of the NABT MT ratio histogram peak height. CONCLUSIONS: This study did not show any statistically significant effect of IVIG on MT MRI quantities. Nevertheless, the markedly different percentage change of the NABT MT ratio histogram peak height over time between patients receiving placebo and treated patients suggests a possible role of IVIG treatment in preventing the loss of "truly" normal brain tissue in SPMS patients. 相似文献
84.
85.
Our objective is to advance the life course analytical framework by demonstrating a model for testing two of its tenets. The first is whether the individual's developmental history conditions the response to a turning point event. The second is whether the influence of a major life event upon an individual's developmental course depends upon the timing of the event. We test both propositions in an analysis of the effect of grade retention on a child's trajectory of physical aggression. Our analysis is based on data from a longitudinal study of 1,037 boysfrom schools in the lowest socioeconomic areas in Montreal, Canada. We find clear evidence that a developmental history of physical aggression conditions the child's response to grade retention. The evidence on whether the timing of retention affects this response is less clear. 相似文献
86.
87.
Biochemical characterization of TEM-92 extended-spectrum beta-lactamase,a protein differing from TEM-52 in the signal peptide
下载免费PDF全文
![点击此处可从《Antimicrobial agents and chemotherapy》网站下载免费的PDF全文](/ch/ext_images/free.gif)
Perilli M Segatore B De Massis MR Pagani L Luzzaro F Rossolini GM Amicosante G 《Antimicrobial agents and chemotherapy》2002,46(12):3981-3983
A bla(TEM-92) gene was cloned from a Proteus mirabilis isolate and expressed in Escherichia coli. Production of the enzyme caused reduction of susceptibility to penicillins and narrow- to expanded-spectrum cephalosporins but not to moxalactam and cephamycins. Determination of kinetic parameters with the purified enzyme revealed hydrolysis of expanded-spectrum cephalosporins, while cephamycins, moxalactam, and aztreonam were very poorly or not hydrolyzed. Clavulanate and penicillanic acid sulfones acylated TEM-92 slowly, and deacylation occurred at measurable rates. 相似文献
88.
Four-year treatment with octreotide-long-acting repeatable in 110 acromegalic patients: predictive value of short-term results? 总被引:11,自引:0,他引:11
Cozzi R Attanasio R Montini M Pagani G Lasio G Lodrini S Barausse M Albizzi M Dallabonzana D Pedroncelli AM 《The Journal of clinical endocrinology and metabolism》2003,88(7):3090-3098
The effects of a very prolonged treatment with octreotide (OC)-long-acting repeatable (LAR) were retrospectively evaluated in 110 patients with acromegaly, showing a GH/IGF-I decrease of at least 20% vs. baseline after a short-term (6-month) OC-LAR challenge. OC-LAR was given (20 mg, im, every 28 d for 3 injections, then individually tailored) as adjuvant treatment (AT) in 59. The other 51 [primary treatment (PT)] were naive or previously treated by pharmacotherapy. IGF-I normalized in 83 patients [75%; from 770 +/- 26 (mean +/- SE) to 276 +/- 15 micro g/liter; P < 0.0001; median follow-up, 30 months; range, 18-54 months). A progressive increase in the rate of IGF-I normalization was observed. GH fell to less than 2.5 micro g/liter in 72% and to less than 1 micro g/liter in 27% (from 20.7 +/- 2.4 to 2.2 +/- 0.2 micro g/liter; P < 0.0001). PT and AT patients achieved similar final GH/IGF-I levels and rates of normalization. Patients attaining safe GH and normal IGF-I had GH levels below 5 micro g/liter after 3 months and IGF-I levels below 550 micro g/liter after 6 months. No tachyphylaxis was observed. The up-titration to 30 mg improved IGF-I suppression. Elderly patients had greater sensitivity. Tumor shrank in 46% of assessable patients, in 77% of PT patients, and in 91% of naive patients. The powerful suppression of GH/IGF-I levels without tachyphylaxis, the finding of progressive increase in the rate of IGF-I normalization and of superimposable effects in PT and AT patients, and the predictive value of short-term results support the role of PT of acromegaly with OC-LAR in at least some patients. 相似文献
89.
Pagani L Migliavacca R Pallecchi L Matti C Giacobone E Amicosante G Romero E Rossolini GM 《Journal of clinical microbiology》2002,40(4):1549-1552
Beta-lactamase production was detected in 147 (52%) of 282 consecutive nonduplicate Proteus mirabilis isolates obtained over a 1-year period from the S. Matteo Hospital of Pavia (northern Italy). Seventy isolates (48% of the beta-lactamase producers) were found to produce extended-spectrum beta-lactamases (ESBLs), identified as PER-1 (first report in this species) and TEM-52 in 52 and 18 isolates, respectively. Analysis of clonal diversity of the ESBL producers suggested different spreading patterns for the two ESBL determinants. 相似文献
90.