全文获取类型
收费全文 | 20524篇 |
免费 | 1003篇 |
国内免费 | 201篇 |
专业分类
耳鼻咽喉 | 152篇 |
儿科学 | 452篇 |
妇产科学 | 177篇 |
基础医学 | 2342篇 |
口腔科学 | 411篇 |
临床医学 | 1188篇 |
内科学 | 6177篇 |
皮肤病学 | 457篇 |
神经病学 | 1373篇 |
特种医学 | 870篇 |
外科学 | 3439篇 |
综合类 | 91篇 |
一般理论 | 3篇 |
预防医学 | 483篇 |
眼科学 | 483篇 |
药学 | 1264篇 |
中国医学 | 40篇 |
肿瘤学 | 2326篇 |
出版年
2023年 | 174篇 |
2022年 | 320篇 |
2021年 | 599篇 |
2020年 | 327篇 |
2019年 | 451篇 |
2018年 | 501篇 |
2017年 | 402篇 |
2016年 | 483篇 |
2015年 | 515篇 |
2014年 | 674篇 |
2013年 | 787篇 |
2012年 | 1349篇 |
2011年 | 1495篇 |
2010年 | 889篇 |
2009年 | 675篇 |
2008年 | 1154篇 |
2007年 | 1297篇 |
2006年 | 1230篇 |
2005年 | 1218篇 |
2004年 | 1135篇 |
2003年 | 1067篇 |
2002年 | 1090篇 |
2001年 | 297篇 |
2000年 | 277篇 |
1999年 | 326篇 |
1998年 | 244篇 |
1997年 | 209篇 |
1996年 | 188篇 |
1995年 | 154篇 |
1994年 | 139篇 |
1993年 | 129篇 |
1992年 | 190篇 |
1991年 | 180篇 |
1990年 | 164篇 |
1989年 | 193篇 |
1988年 | 144篇 |
1987年 | 144篇 |
1986年 | 123篇 |
1985年 | 119篇 |
1984年 | 84篇 |
1983年 | 62篇 |
1982年 | 40篇 |
1981年 | 36篇 |
1980年 | 43篇 |
1979年 | 53篇 |
1978年 | 32篇 |
1977年 | 33篇 |
1974年 | 25篇 |
1971年 | 30篇 |
1968年 | 27篇 |
排序方式: 共有10000条查询结果,搜索用时 8 毫秒
1.
Yosuke Homma Takashi Shiga Hiraku Funakoshi Dai Miyazaki Atsushi Sakurai Yoshio Tahara Ken Nagao Naohiro Yonemoto Arino Yaguchi Naoto Morimura 《The American journal of emergency medicine》2019,37(2):241-248
Objective
This study assessed the association between the timing of first epinephrine administration (EA) and the neurological outcomes following out-of-hospital cardiac arrests (OHCAs) with both initial shockable and non-shockable rhythms.Methods
This was a post-hoc analysis of a multicenter prospective cohort study (SOS-KANTO 2012), which registered OHCA patients in the Kanto region of Japan from January 2012 to March 2013. We included consecutive adult OHCA patients who received epinephrine. The primary result included 1-month favorable neurological outcomes defined as cerebral performance category (CPC) 1 or 2. Secondary results included 1-month survival and return of spontaneous circulation (ROSC) after arrival at the hospital. Multivariable logistic regression analysis determined the association between delay per minute of the time from call to first EA in both pre- or in-hospital settings and outcomes.Results
Of the 16,452 patients, 9344 were eligible for our analyses. In univariable analysis, the delay in EA was associated with decreased favorable neurological outcomes only when the initial rhythm was a non-shockable rhythm. In multivariable analyses, delay in EA was associated with decreased ROSC (adjusted odds ratio [OR] for one minute delay, 0.97; 95% confidence interval [CI], 0.96–0.98) and 1-month survival (adjusted OR, 0.95; 95% CI, 0.92–0.97) when the initial rhythm was a non-shockable rhythm, whereas during a shockable rhythm, delay in EA was not associated with decreased ROSC and 1-month survival.Conclusions
While assessing the effectiveness of epinephrine for OHCA, we should consider the time-limited effects of epinephrine. Additionally, consideration of early EA based on the pathophysiology is needed. 相似文献2.
Takao Itoi Atsushi Sofuni Fumihide Itokawa Yasushi Shinohara Kazuya Takeda Kazuto Nakamura Toshio Kurihara Takayoshi Tsuchiya Fuminori Moriyasu 《Digestive endoscopy》2006,18(3):232-238
We describe our methods and outcomes of multidisciplinary treatments in patients with unresectable hilar cholangiocarcinoma. Fifty‐seven patients with a known outcome were enrolled. Thirty‐four of 57 patients were treated and evaluated by salvage therapy. For salvage therapy, we used internal and external radiotherapy, photodynamic therapy, YAG laser therapy and microwave coagulation therapy. The median survival time was 548 days for the group receiving salvage therapy and 198 days for the group not receiving this treatment. In conclusion, although no randomization of the patients was performed in this retrospective study, our present data provide convincing evidence that salvage therapy is a useful therapeutic approach for unresectable hilar cholangiocarcinomas. 相似文献
3.
4.
Tanaka Takeo Kobayashi Masao Saito Osamu Kamada Nanao Kuramoto Atsushi Usui Tomofusa 《Clinica chimica acta; international journal of clinical chemistry》1981,117(2):121-131
The biochemical activities of 8 lysosomal acid hydrolases in leukemic cells from 48 patients were examined. Characteristic alterations were found in α-mannosidase, β-galactosidase and N-acetyl-β-glucosaminidase activities of leukemic cells. The level of α-mannosidase activity was much higher in myelo(mono)genous leukemias (AML, AMoL, AMMoL, CML and CMMoL) than in lymphogenous ones (ALL, T-cell leukemia, hairy cell leukemia and CLL) without exception. The β-galactosidase activity also differed as a result of α-mannosidase, except in T-cell leukemia. In T-cell leukemia it was within the range of normal lymphocytes, but in the other lymphogenous leukemias it was significantly below normal. N-acetyl-β-glucosaminidase activity in myelo(mono)genous leukemic cells was above the range of normal granulocytes. The changes in these enzyme levels were consistent. The lymphocytic or myelocytic nature of three cases of acute undifferentiated leukemia could be determined by enzyme studies. In two cases it was lymphocytic and in one it was myelocytic. The enzymatic abnormalities were also found in morphologically mature neutrophils from patients with not only chronic types (CML, CMMoL) but also acute types (AMoL, AMMoL) of leukemias, and were similar to those of their respective leukemic cells. Analysis of lysosomal enzymes (at least three of those mentioned above), can elucidate one of the biochemical properties of leukemic cells and may be valuable in the differentiation of leukemias. 相似文献
5.
M Z Atassi M Yoshioka G S Bixler Jr 《Proceedings of the National Academy of Sciences of the United States of America》1989,86(17):6729-6733
Processing of a protein antigen into fragments is believed to be a prerequisite for its presentation by the antigen-presenting cell to the T cell. This model would predict that, in oligomeric proteins, T cells prepared with specificity for regions that are buried within subunit association surfaces should recognize the respective regions in vitro equally well on the isolated subunit or on the oligomer. Three hemoglobin (Hb) alpha-chain synthetic peptides, corresponding to areas that are situated either completely [alpha-(31-45)] or partially [alpha-(41-45) and alpha-(81-95)] within the interface between the alpha and beta subunits of Hb, and a fourth peptide representing a completely exposed area in tetrameric Hb were used as immunogens in SJL/J (H-2s) mice. Peptide-primed T cells were passaged in vitro with the respective peptide to obtain peptide-specific T-lymphocyte lines. T-cell clones were isolated from these lines by limiting dilution. T-cell lines and clones that were specific for buried regions in the subunit association surfaces recognized the free peptide and the isolated subunit but not the Hb tetramer. On the other hand, T cells with specificity against regions that are not involved in subunit interaction and are completely exposed in the tetramer recognized the peptide, the isolated subunit, and the oligomeric protein equally well. The responses of the T-cell lines and clones were major histocompatibility complex-restricted. Since the same x-irradiated antigen-presenting cells were employed, the results could not be attributed to differences or defects in Hb processing. The findings indicate that in vitro the native (unprocessed and undissociated) oligomeric protein was the trigger of major histocompatibility complex-restricted T-cell responses. 相似文献
6.
Pathogenic role of connective tissue growth factor (CTGF/CCN2) in osteolytic metastasis of breast cancer. 总被引:5,自引:0,他引:5
7.
PURPOSE: The aim of this study is (1) to develop a new method of risk classification for clinically localized prostate cancer; (2) to examine it in terms of compatibility with existing data such as nomograms; and (3) to compare it with existing risk-grouping methods. MATERIAL AND METHODS: The new grading system introduced here consists of three factors. The first is a prostate-specific antigen (PSA) of 4.1-10.0 ng/ml (score 0), 10.1-20.0 ng/ml (score 1), and >20.0 ng/ml (score 2). The second is a Gleason score (GS) of 6 (score 0), 7 (score 1), and 8-10 (score 2). The third is T classifications (UICC 2002) of T1c-T2a (score 0), T2b-T2c (score 1), and T3a (score 2). The sum of the three scores was named Prostate Risk Index (PRIX). Then, the compatibility of PRIX with the Partin Table, Kattan Nomogram, and Roach's formula was examined. At the same time, PRIX was compared with D'Amico, the National Comprehensive Cancer Network (NCCN), and Seattle classifications. RESULTS: PRIX 0 corresponded to 1-2% of pathologic lymph node involvement (pLN+) according to the Partin Table; PRIX 1 to 3-4%; PRIX 2 to 7-10%; PRIX 3 to 14-18%; PRIX 4 to 24-29%; PRIX 5 to 32-37%; and PRIX 6 to 42%. PRIX well separated the risks with relatively narrow ranges of probability, while D'Amico, NCCN, and Seattle classifications generally gave wide ranges especially for high-risk groups, both in the Partin Table and Kattan Nomogram. Roach's formula sometimes overestimated the risk compared to the Partin Table. CONCLUSION: PRIX fully corresponded to the Partin Table in terms of pLN+, and corresponded to the other nomograms better than any existing risk-grouping method. PRIX may thus function as a prognostic factor or contribute to patient selection in clinically localized prostate cancer. 相似文献
8.
9.
10.