全文获取类型
收费全文 | 95030篇 |
免费 | 9268篇 |
国内免费 | 4779篇 |
专业分类
耳鼻咽喉 | 2606篇 |
儿科学 | 388篇 |
妇产科学 | 1707篇 |
基础医学 | 10726篇 |
口腔科学 | 3400篇 |
临床医学 | 6885篇 |
内科学 | 11839篇 |
皮肤病学 | 1976篇 |
神经病学 | 218篇 |
特种医学 | 4344篇 |
外国民族医学 | 122篇 |
外科学 | 13846篇 |
综合类 | 16570篇 |
现状与发展 | 23篇 |
预防医学 | 2093篇 |
眼科学 | 400篇 |
药学 | 4658篇 |
14篇 | |
中国医学 | 1142篇 |
肿瘤学 | 26120篇 |
出版年
2024年 | 179篇 |
2023年 | 1377篇 |
2022年 | 2788篇 |
2021年 | 3670篇 |
2020年 | 3181篇 |
2019年 | 3007篇 |
2018年 | 2875篇 |
2017年 | 3281篇 |
2016年 | 3708篇 |
2015年 | 4256篇 |
2014年 | 6224篇 |
2013年 | 5465篇 |
2012年 | 5655篇 |
2011年 | 6153篇 |
2010年 | 5014篇 |
2009年 | 4932篇 |
2008年 | 5144篇 |
2007年 | 5429篇 |
2006年 | 5072篇 |
2005年 | 4531篇 |
2004年 | 3578篇 |
2003年 | 3139篇 |
2002年 | 2680篇 |
2001年 | 2579篇 |
2000年 | 2187篇 |
1999年 | 1754篇 |
1998年 | 1596篇 |
1997年 | 1430篇 |
1996年 | 1258篇 |
1995年 | 1068篇 |
1994年 | 978篇 |
1993年 | 679篇 |
1992年 | 594篇 |
1991年 | 517篇 |
1990年 | 437篇 |
1989年 | 380篇 |
1988年 | 364篇 |
1987年 | 291篇 |
1986年 | 240篇 |
1985年 | 260篇 |
1984年 | 212篇 |
1983年 | 151篇 |
1982年 | 172篇 |
1981年 | 147篇 |
1980年 | 136篇 |
1979年 | 109篇 |
1978年 | 76篇 |
1977年 | 53篇 |
1976年 | 45篇 |
1975年 | 11篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
161.
Ken Yamaguchi Katsumi Aoyagi Ken-ichi Urakami Toyoharu Fukutani Noboru Maki Shigehiro Yamamoto Kotomi Otsubo Yoshio Miyake Tetsuro Kodama 《Cancer science》1995,86(7):698-705
Our previous study demonstrated that pro-gastrin-releasing peptide(31–98), or ProGRP, is a specific tumor marker in patients with small cell lung carcinoma (SCLC). Using a newly developed, highly sensitive enzyme-linked immunosorbent assay (ELISA) for ProGRP, we analyzed 1,446 samples including those obtained from 478 lung cancer patients to evaluate the clinical usefulness of this ELISA. Several properties indicated that ProGRP is a useful tumor marker for SCLC. First, ProGRP was specifically elevated in SCLC patients. In non-SCLC patients and patients with non-tumorous lung diseases, its serum level was very rarely elevated. Secondly, ProGRP was a reliable marker, in terms of the marked elevation of serum ProGRP levels in SCLC patients. Thirdly, serum ProGRP levels were elevated in SCLC patients even at a relatively early stage of this disease. Fourthly, changes in the serum ProGRP level showed an excellent correlation with the therapeutic responses in SCLC patients. Neuron-specific enolase (NSE) is accepted as a tumor marker of SCLC patients. With the aim of comparing ProGRP and NSE as tumor markers for SCLC patients, we measured serum NSE levels in all samples collected in the present study. We found that ProGRP was superior to NSE in terms of sensitivity, specificity and reliability. Therefore, we consider that ProGRP can play a major role as a clinical tumor marker for SCLC patients. 相似文献
162.
Abstract: This review examines the liver-damaging side effects of anabolic-androgenic steroids (AAS). It seems that AAS can cause development of peliosis hepatis, subcellular changes of hepatocytes, hepatocellular hyperplasia and hepatocellular adenomas. On the other hand, it has not been convincingly proved that AAS can cause development of hepatocellular carcinomas when used in the usual therapeutic doses. Tumours reported as hepatocellular carcinomas caused by AAS seem to be hyperplastic lesions of a benign nature able to regress with withdrawal of the putative agent. The effects of untraditional combinations and high-dose AAS are not yet known, leaving the possibility of a carcinogenic effect in those cases. 相似文献
163.
Mayumi Ujihara Sumiko Hamanaka Sachie Matsuda Fumitaka Numa Hiroshi Kato 《The Journal of dermatology》1994,21(1):56-58
A 76-year-old female was admitted with many bullae and erythema on her trunk and extremities. A biopsy specimen showed significant intercellular edema in the lower epidermis and eosinophilic infiltration into the dermis and the epidermis. Immunofluorescent staining revealed the deposition of IgG in the intercellular area of her prickle cells. From these histologic findings and the typical clinical features, we diagnosed her as having pemphigus vulgaris. Examination of her blood revealed that she also suffered from autoimmune hemolytic anemia. Despite intensive treatment with prednisolone, she finally died. This case is of interest because of its rarity and the TNFα detected significantly in the blister fluid of this patient. 相似文献
164.
Nodular hyperplasia surrounding fibrolamellar carcinoma 总被引:2,自引:0,他引:2
We report a case of acetaminophen-induced liver necrosis in a 14-year-old girl. At autopsy, a 9 cm subcapsular nodule was present in the right lobe of the liver which showed distinct zonation: a central greyish white area of fibrolamellar carcinoma with a peripheral fleshy, tan-coloured rim ranging from 1 to 2 cm in thickness. This peripheral zone consisted of nodular, hyperplastic parenchyma resembling the changes seen in focal nodular hyperplasia, and stood out from the adjacent necrotic parenchyma. The sparing of this zone from the deleterious effects of acetaminophen provides indirect evidence of a predominantly arterial rather than portal blood supply to this region. The arterial supply was most probably derived from the tumour vasculature and may explain the parenchymal hyperplasia sometimes reported adjacent to a fibrolamellar carcinoma. Awareness of this phenomenon is essential when evaluating a needle biopsy, as sampling of this region may lead to a false negative diagnosis. 相似文献
165.
166.
Lise Pedersen Susanne Holck Torben Schiødt Karin Zedeler Henning T. Mouridsen 《Breast cancer research and treatment》1989,14(1):91-99
Summary One hundred thirty-one breast carcinomas with medullary features, registered in the Danish Breast Cancer Cooperative Group from 1977–1982, have been histopathologically reviewed by two senior pathologists and classified as typical medullary carcinoma (TMC), atypical medullary carcinoma (AMC), and non-medullary carcinoma (NMC). Diagnostic criteria were based on those put forward by Ridolfiet al. and Fisheret al. The procedure was repeated with an interval of about one year by both pathologists. The diagnostic interobserver agreement was 72% with a Kappa of 0.55. The intraobserver agreement was 77% and 63% with Kappa values of 0.64 and 0.44, respectively. To see whether the observed inter- and intraobserver variability had any prognostic implications, diagnostic subgroups for both pathologists were analyzed with Kaplan Meier plots for recurrence-free survival (RFS) and with log rank tests. In the first evaluation pathologist 1 segregated a group of TMC with a significantly better RFS than for the NMC group, and pathologist 2 segregated a group of TMC with a corresponding strong trend. These findings could not, however, be reproduced in the second evaluation. The study indicates that the criteria of TMC and AMC as proposed by Ridolfiet al. need to be sharpened and simplified in order to reduce inter-and intraobserver variability. Larger studies with a control group of infiltrating ductal carcinomas are mandatory to elucidate the clinical importance of the diagnoses of Typical and Atypical Medullary Carcinoma of the breast. 相似文献
167.
Exposure of H69 small cell lung carcinoma cells to nicotinic agonists resulted in a significant increase (up to 100%) in cell number after 6 to 12 days. The effect of nicotine (10−8 M to 10−4 M) was both dose and time dependent as was that of another nicotinic agonist cytisine (10−6 M to 10−4 M). Interstingly, both the nicotine and cytisine induced increases in H69 cell number were blocked by α-bungarotoxin, as well as d-tubocurarine a nicotinic blocker which appears to interact with most nicotinic receptors. These results suggest that the nicotine induced increase in cell number is mediated through an interaction at the nicotinic α-bungarotoxin receptor. This idea is further supported by experiments which show (1) that H69 cells possess high affinity α-bungarotoxin sites (Kd = 25 nM, Bmax = 10.4 fmol/106 cells) with the characteristics of a nicotinic α-bungarotoxin receptor and (2) that the potencies of nicotinic receptor ligands in the α-bungarotoxin binding assay were similar to those observed in the functional studies. Northern analysis showed that mRNA for α7, a putative nicotinic α-bungarotoxin binding subunit, and for α5 were present in H69 cells. The present data provide further evidence that nicotine increases cell number in small cell lung carcinoma and are the first to show that this effect is mediated through an interaction at the nicotinic α-bungarotoxin receptor population. These results suggest that the α-bungarotoxin site may be involved in modulating proliferative responses in neuroendocrine derived SCLC cells. 相似文献
168.
169.
近年来,应用免疫组织化学技术观察肝组织内乙型肝炎表面抗原(HBsAg)的研究屡有报导。大多数作者认为乙型肝炎在肝硬化、肝癌的发病中起重要作用;但有的流行病学研究则认为在某些地区,肝炎不是肝癌的病因。我省是肝癌高发区之一,关于这方面尚未见有报道。本文应用免疫酶法标记定位观察肝硬化、肝癌病人肝组织中HBsAg,以探讨本地区肝炎与肝硬化和肝细胞癌的关系。 相似文献
170.
J A Arcadi 《Journal of surgical oncology》1992,49(1):35-38
Bilateral subcapsular orchiectomy was performed in six patients with metastatic prostatic carcinoma. In these patients the serum levels of testosterone were determined serially up to twenty-four hours. Castrate levels of testosterone were achieved in about two and one-half hours. This is the first published report of such a rapid decrease in serum testosterone. Castrate levels of serum testosterone using the luteinizing hormone releasing hormone (LH-RH) agonists are achieved in fourteen to twenty-one days. The relative cost of orchiectomy and LH-RH agonists, for thirty-six months, was $2,042.00 and $12,780.00, respectively. LH-RH agonists may be effective for only a year. Urologists are urged to continue using bilateral subcapsular orchiectomy and not use LH-RH agonists in the management of metastatic prostatic carcinoma. 相似文献