全文获取类型
收费全文 | 12006篇 |
免费 | 521篇 |
国内免费 | 79篇 |
专业分类
耳鼻咽喉 | 60篇 |
儿科学 | 249篇 |
妇产科学 | 120篇 |
基础医学 | 1274篇 |
口腔科学 | 159篇 |
临床医学 | 873篇 |
内科学 | 3302篇 |
皮肤病学 | 259篇 |
神经病学 | 768篇 |
特种医学 | 652篇 |
外科学 | 2207篇 |
综合类 | 34篇 |
预防医学 | 300篇 |
眼科学 | 157篇 |
药学 | 778篇 |
中国医学 | 54篇 |
肿瘤学 | 1360篇 |
出版年
2023年 | 47篇 |
2022年 | 109篇 |
2021年 | 221篇 |
2020年 | 129篇 |
2019年 | 175篇 |
2018年 | 224篇 |
2017年 | 193篇 |
2016年 | 209篇 |
2015年 | 239篇 |
2014年 | 308篇 |
2013年 | 391篇 |
2012年 | 676篇 |
2011年 | 682篇 |
2010年 | 394篇 |
2009年 | 310篇 |
2008年 | 561篇 |
2007年 | 686篇 |
2006年 | 621篇 |
2005年 | 702篇 |
2004年 | 723篇 |
2003年 | 750篇 |
2002年 | 648篇 |
2001年 | 365篇 |
2000年 | 383篇 |
1999年 | 361篇 |
1998年 | 159篇 |
1997年 | 147篇 |
1996年 | 108篇 |
1995年 | 85篇 |
1994年 | 81篇 |
1993年 | 85篇 |
1992年 | 168篇 |
1991年 | 164篇 |
1990年 | 179篇 |
1989年 | 153篇 |
1988年 | 149篇 |
1987年 | 128篇 |
1986年 | 119篇 |
1985年 | 117篇 |
1984年 | 66篇 |
1983年 | 82篇 |
1982年 | 32篇 |
1981年 | 29篇 |
1980年 | 25篇 |
1979年 | 63篇 |
1978年 | 40篇 |
1977年 | 25篇 |
1975年 | 39篇 |
1974年 | 28篇 |
1970年 | 36篇 |
排序方式: 共有10000条查询结果,搜索用时 265 毫秒
51.
Are cytokines possible mediators of cancer cachexia? 总被引:1,自引:0,他引:1
Yoshikazu Noguchi Takaki Yoshikawa Akihiko Matsumoto Gösta Svaninger Johan Gelin 《Surgery today》1996,26(7):467-475
The possible role of cytokines in the development of cancer cachexia was reviewed from the literature. Tumor necrosis factor (TNF)-alpha, interleukin (IL)-1, IL-6, interferon (IFN)-gamma and leukemia inhibitory factor (LIF) can elicit many but not all host changes seen in cancer cachexia, including loss of appetite, loss of body weight, and the induction of acute-phase protein synthesis. However, these cytokines are not always demonstrated in the circulation of the cancer patients. The inability to detect circulating cytokines may be due to their low rate of production, their short half-life and rapid clearance from plasma, or their mode of action (autocrine or paracrine). Different cytokines are induced to stimulate the same response. This is very different from hormonal regulation, where a hormone acts on a cell directly through a specific receptor without depending on other mediators. Specific antibodies including anti-IFN-gamma, anti-TNF and anti-IL-6 antibodies, as well as the cyclooxygenase inhibitor indomethacin, have been used to reverse cancer cachexia. Overlapping physiologic activities make it unlikely that a single substance is the sole cause of cancer cachexia. It is hoped that further investigation on other cytokines and their possible relationships with hormones will help to clarify the mechanisms of cancer cachexia in the near future.This work was supported by a grant from the Japan-Sweden Foundation in 1991. 相似文献
52.
Suzuki M Okuyama T Yoshikawa K Yamaoka Y Ariyasu T Fujita M Tankawa H Sugiyama T Takahashi R 《Pathology international》1996,46(1):46-53
Overexpression of p53 protein, epidermal growth factor receptor (EGF-R), and c-erbB-2 protein was assessed by immunohistochemical staining of formalin-fixed, paraffin-embedded tissue from 64 invasive breast tumors. The correlation between abnormal expression of each protein and various disease parameters, including lymph node metastasis and histopathologic type and grade was analyzed. Despite the previous proposal, no significant correlation was found between lymph node metastases and overexpression of each gene in the primary tumors. In addition, some metastatic lesions did not always exhibit overexpression, even if it was evident in the primary tumors. Overexpression of c-erbB-2 protein correlated well with Bloom's histological grading. p53 expression was detected most often in tumors with hyperchromatism and more frequent mitosis. Overexpression of c-erbB-2 protein occurred more frequently in p53-positive tumors. The results indicate that abnormal expression of p53 protein causes genetic instability in the early stage of tumor development, resulting in subsequent overexpression of other oncogenes. 相似文献
53.
Koichiro Yuji Shigesaburo Miyakoshi Daisuke Kato Yuji Miura Tomohiro Myojo Naoko Murashige Yukiko Kishi Kazuhiro Kobayashi Eiji Kusumi Hiroto Narimatsu Tamae Hamaki Tomoko Matsumura Masahiro Kami Takahiro Fukuda Shigeru Masuo Kazuhiro Masuoka Atsushi Wake Junichi Ueyama Akiko Yoneyama Ko Miyamoto Haruhisa Nagoshi Michio Matsuzaki Shinichi Morinaga Yoshitomo Muto Yoichi Takeue Shuichi Taniguchi 《Biology of blood and marrow transplantation》2005,11(4):314-318
We report the results of reduced-intensity unrelated cord blood transplantation (RI-UCBT) in patients with advanced malignant lymphoma. Twenty patients (median age, 46.5 years; range, 27-66 years) underwent RI-UCBT with a preparative regimen consisting of fludarabine 125 mg/m2 , melphalan 80 mg/m 2 , and 4 Gy of total body irradiation. The median infused total cell dose was 2.75 x 10(7)/kg (range, 2.3-3.4 x 10(7)/kg). Graft-versus-host disease (GVHD) prophylaxis was composed of cyclosporine or tacrolimus alone. Fifteen patients achieved primary neutrophil engraftment after a median of 20 days. Eight patients developed grade II to IV acute GVHD, and 2 developed chronic GVHD. Of the 16 patients with evaluable disease, 10 achieved a complete response. Primary disease recurred in 1 patient, and transplant-related mortality within 100 days occurred in 8 of 20 patients. The estimated 1-year probability of progression-free survival was 50%. These data suggest that RI-UCBT is a feasible option for patients with refractory lymphoma who lack an HLA-matched donor. 相似文献
54.
The pre-B cell receptor (preBCR) plays critical roles in early B cell differentiation. It has been shown that not all muH chains are capable of pairing with surrogate light (SL) chains to form preBCR. Here, we established a novel system to differentially identify two types of early pre-B cell populations in bone marrow and fetal liver of mice, one producing SL-pairing muH chains and the other producing SL-non-pairing muH chains. The former population accounted for 80% of all the early pre-B cells in adult bone marrow, while it accounted for only 20% of those in fetal liver. Comparison of the two types of pre-B cell populations in fetal liver revealed the structural difference between SL-pairing and -non-pairing muH chains encoded by the V(H)81X segment that was most frequently utilized in fetal liver pre-B cells but rarely expressed by B cells generated in adults. PreBCR played an important role in the positive selection of V(H)81X-muH chains carrying the characteristic sequences of the complementarity-determining region 3 with little or no nibbling or N nucleotide addition, leading to their predominance in neonatal splenic B cells. These fetal-type V(H)81X-muH chains were also detected in adult spleen, but almost exclusively in marginal zone (MZ) B cells in contrast to the adult-type V(H)81X-muH chains. This strongly suggests that neonatally generated and selected B cells expressing the stereotyped V(H)81X-muH chains are maintained in the adult MZ and could function as innate-like lymphocytes. 相似文献
55.
Tamiya G Shinya M Imanishi T Ikuta T Makino S Okamoto K Furugaki K Matsumoto T Mano S Ando S Nozaki Y Yukawa W Nakashige R Yamaguchi D Ishibashi H Yonekura M Nakami Y Takayama S Endo T Saruwatari T Yagura M Yoshikawa Y Fujimoto K Oka A Chiku S Linsen SE Giphart MJ Kulski JK Fukazawa T Hashimoto H Kimura M Hoshina Y Suzuki Y Hotta T Mochida J Minezaki T Komai K Shiozawa S Taniguchi A Yamanaka H Kamatani N Gojobori T Bahram S Inoko H 《Human molecular genetics》2005,14(16):2305-2321
A major goal of current human genome-wide studies is to identify the genetic basis of complex disorders. However, the availability of an unbiased, reliable, cost efficient and comprehensive methodology to analyze the entire genome for complex disease association is still largely lacking or problematic. Therefore, we have developed a practical and efficient strategy for whole genome association studies of complex diseases by charting the human genome at 100 kb intervals using a collection of 27,039 microsatellites and the DNA pooling method in three successive genomic screens of independent case-control populations. The final step in our methodology consists of fine mapping of the candidate susceptible DNA regions by single nucleotide polymorphisms (SNPs) analysis. This approach was validated upon application to rheumatoid arthritis, a destructive joint disease affecting up to 1% of the population. A total of 47 candidate regions were identified. The top seven loci, withstanding the most stringent statistical tests, were dissected down to individual genes and/or SNPs on four chromosomes, including the previously known 6p21.3-encoded Major Histocompatibility Complex gene, HLA-DRB1. Hence, microsatellite-based genome-wide association analysis complemented by end stage SNP typing provides a new tool for genetic dissection of multifactorial pathologies including common diseases. 相似文献
56.
Kaburaki J Kuwana M Ikeda Y 《Rinsho byori. The Japanese journal of clinical pathology》2003,51(7):639-643
The concept of antiphospholipid syndrome(APS) has been widely accepted. Antiphospholipid antibodies originally included anticardiolipin antibodies and lupus anticoagulants as serological marker of APS. However, recent advances have shown that most pathogenic antiphospholipid antibodies are directed to phospholipid binding proteins such as beta 2-glycoprotein I and prothrombin as well as phospholipids. The preliminary classification criteria for definite APS have been advocated as the "Sapporo criteria". Further prospective investigations are required to re-evaluate the clinical significance of so-called antiphospholipid antibodies. 相似文献
57.
Rapid diagnosis of human herpesvirus 6 infection by a novel DNA amplification method, loop-mediated isothermal amplification 总被引:13,自引:0,他引:13 下载免费PDF全文
Ihira M Yoshikawa T Enomoto Y Akimoto S Ohashi M Suga S Nishimura N Ozaki T Nishiyama Y Notomi T Ohta Y Asano Y 《Journal of clinical microbiology》2004,42(1):140-145
A novel nucleic acid amplification method, termed loop-mediated isothermal amplification (LAMP), which amplifies DNA with high specificity, efficiency, and rapidity under isothermal conditions, may be a valuable tool for the rapid detection of infectious agents. LAMP was developed for human herpesvirus 6 (HHV-6), and its reliability was evaluated in this study. Although LAMP products were detected in HHV-6 B and HHV-6 A DNA, they were not detected in HHV-7 and human cytomegalovirus DNA. The sensitivity of the original HHV-6 LAMP protocol was 50 copies/tube. In order to increase the method's sensitivity, HHV-6 LAMP was modified by increasing the primer concentration. As a result of the modification, sensitivity increased to 25 copies/tube. After these initial validation studies, 13 patients with fever were tested for HHV-6 by viral isolation, serological analysis, and HHV-6 LAMP. In three of the eight patients with primary HHV-6 infection, HHV-6 DNA was detected in whole blood by the original HHV-6 LAMP protocol in not only the acute phase but also the convalescent phase. HHV-6 DNA was detected by modified HHV-6 LAMP in all eight plasma samples collected in the acute phase; however, no HHV-6 DNA was detected in plasma samples collected in the convalescent phase. Although HHV-6 DNA was detected in both the acute and convalescent phases of whole-blood samples in patients with past HHV-6 infection, it was not detected in plasma samples that did not contain latent viral DNA. Thus, detection of HHV-6 DNA in plasma by using this modified HHV-6 LAMP protocol is appropriate for diagnosis of active HHV-6 infection. 相似文献
58.
Histopathological studies on virulence of dipeptidyl aminopeptidase IV (DPPIV) of Porphyromonas gingivalis in a mouse abscess model: use of a DPPIV-deficient mutant 下载免费PDF全文
Yagishita H Kumagai Y Konishi K Takahashi Y Aoba T Yoshikawa M 《Infection and immunity》2001,69(11):7159-7161
To elucidate the role of dipeptidyl aminopeptidase IV (DPPIV) in the virulence of Porphyromonas gingivalis, mice were infected with either a wild-type strain or a DPPIV-deficient mutant using an abscess model. Histopathological analysis of the resulting lesions indicated that DPPIV participates in virulence through the destruction of connective tissue and the less effective mobilization of inflammatory cells. 相似文献
59.
Pathogenesis of Rinderpest Virus Infection in Rabbits I. Clinical Signs, Immune Response, Histological Changes, and Virus Growth Patterns 下载免费PDF全文
Kazuya Yamanouchi Fumitoshi Chino Fumio Kobune Akiko Fukuda Yasuhiro Yoshikawa 《Infection and immunity》1974,9(2):199-205
Rabbits were intravenously inoculated with an attenuated rinderpest virus (L strain), and general patterns of the disease were investigated. The rabbits developed fever with concomitant occurrence of diarrhea and lymphopenia. Early production of interferon was followed by a rise of neutralizing antibody. Histological examinations revealed an involvement of all of the lymphoid tissues, with primary lesions consisting of necrosis of the lymphoid follicles and formation of giant cells. Immunofluorescent examinations suggested that the virus growth was present in almost all of the lymphoid tissues. The possibility of application of this experimental system for the study of systemic infection by measles virus was discussed. 相似文献
60.