全文获取类型
收费全文 | 6739篇 |
免费 | 289篇 |
国内免费 | 58篇 |
专业分类
耳鼻咽喉 | 75篇 |
儿科学 | 101篇 |
妇产科学 | 165篇 |
基础医学 | 846篇 |
口腔科学 | 195篇 |
临床医学 | 483篇 |
内科学 | 1725篇 |
皮肤病学 | 179篇 |
神经病学 | 470篇 |
特种医学 | 369篇 |
外科学 | 873篇 |
综合类 | 18篇 |
一般理论 | 1篇 |
预防医学 | 294篇 |
眼科学 | 119篇 |
药学 | 466篇 |
中国医学 | 17篇 |
肿瘤学 | 690篇 |
出版年
2023年 | 43篇 |
2022年 | 100篇 |
2021年 | 186篇 |
2020年 | 90篇 |
2019年 | 135篇 |
2018年 | 145篇 |
2017年 | 109篇 |
2016年 | 118篇 |
2015年 | 126篇 |
2014年 | 169篇 |
2013年 | 197篇 |
2012年 | 270篇 |
2011年 | 301篇 |
2010年 | 190篇 |
2009年 | 147篇 |
2008年 | 285篇 |
2007年 | 333篇 |
2006年 | 281篇 |
2005年 | 303篇 |
2004年 | 275篇 |
2003年 | 318篇 |
2002年 | 291篇 |
2001年 | 271篇 |
2000年 | 238篇 |
1999年 | 230篇 |
1998年 | 89篇 |
1997年 | 62篇 |
1996年 | 58篇 |
1995年 | 39篇 |
1994年 | 39篇 |
1993年 | 34篇 |
1992年 | 156篇 |
1991年 | 126篇 |
1990年 | 135篇 |
1989年 | 138篇 |
1988年 | 105篇 |
1987年 | 113篇 |
1986年 | 110篇 |
1985年 | 91篇 |
1984年 | 58篇 |
1983年 | 48篇 |
1981年 | 27篇 |
1979年 | 73篇 |
1978年 | 41篇 |
1977年 | 35篇 |
1973年 | 28篇 |
1971年 | 26篇 |
1970年 | 30篇 |
1969年 | 35篇 |
1967年 | 30篇 |
排序方式: 共有7086条查询结果,搜索用时 15 毫秒
71.
72.
Shimoya K Moriyama A Ogata I Nobunaga T Koyama M Azuma C Murata Y 《Molecular human reproduction》2000,6(9):829-834
Secretory leukocyte protease inhibitor (SLPI) is a potent inhibitor of human leukocyte elastase. We investigated whether SLPI was present in the peritoneal fluid of women with endometriosis and to clarify the role of SLPI in the pathogenesis of endometriosis. Western blot analyses revealed that SLPI protein was detected as a 12 kDa band in peritoneal fluid. The peritoneal fluid concentrations of SLPI, elastase and interleukin-6 were assayed by enzyme-linked immunosorbent assays (ELISA). SLPI concentrations and the SLPI/elastase ratio in the peritoneal fluid of women with endometriosis were higher than in samples from women without endometriosis. There was no significant correlation between concentrations of SLPI and interleukin-6 in the peritoneal fluid. Immunohistochemistry using an anti-SLPI polyclonal antibody revealed positive staining in peritoneal macrophages, but not lymphocytes. The present findings suggest that SLPI found in the peritoneal fluid of patients with endometriosis may contribute to the pathogenesis of endometriosis. 相似文献
73.
Tetsuya Murata Toshihiko Soga Kazuhiro Tajima Kaoru Saito Yoshinori Komeda Sergio Ossamu Loshii Taizo Shiraishi Teruyo Sakakura Ryuichl Yatani 《Pathology international》1994,44(2):138-144
Sarcomatoid carcinoma is a rare variant of malignant tumor arising from the urinary tract. This tumor had been termed carcinosarcoma because of its carcinomatous and sarcomatous components. There is still some confusion in the terminology between true carcinosarcoma and sarcomatoid carcinoma; however, the latter is now regarded as primarily a malignant epithelial tumor with pseudosarcomatous transformation.
Four cases of sarcomatoid carcinoma arising from the urinary tract are reported. The patients were a 77 year old female, and three males aged 62, 69 and 80 years. All but the eldest patient complained of gross hematurla. Surgical removal was performed in the younger three cases, and an autopsy was done in the remaining case. All the tumors were macroscopically polypoid. Histopathologic examination revealed fasciculated spindle-cell tumors with myxold stroma or malignant fibrous histiocytoma-like spindle cell tumors. The epithelial nature was proven in these sarcomatous cells by immunohistochemical andlor electron-microscopic examinations. Only a small amount of squamous cell carcinoma components was also evident in the latter three cases. Although the younger three patients were alive at 44, 23 and 39 months'follow-up, respectively, constant careful monitoring Is recommended. 相似文献
Four cases of sarcomatoid carcinoma arising from the urinary tract are reported. The patients were a 77 year old female, and three males aged 62, 69 and 80 years. All but the eldest patient complained of gross hematurla. Surgical removal was performed in the younger three cases, and an autopsy was done in the remaining case. All the tumors were macroscopically polypoid. Histopathologic examination revealed fasciculated spindle-cell tumors with myxold stroma or malignant fibrous histiocytoma-like spindle cell tumors. The epithelial nature was proven in these sarcomatous cells by immunohistochemical andlor electron-microscopic examinations. Only a small amount of squamous cell carcinoma components was also evident in the latter three cases. Although the younger three patients were alive at 44, 23 and 39 months'follow-up, respectively, constant careful monitoring Is recommended. 相似文献
74.
To determine the role of free radical mechanisms in the pathogenesis of amyotrophic lateral sclerosis (ALS), cerebrospinal fluid concentrations of oxidized nitric oxide (NO) products (nitrite and nitrate) and reduced and oxidized forms of glutathione (GSH and GSSG, respectively) were compared between patients with the sporadic form of ALS (SALS) and controls. In the SALS patients, the nitrate levels were significantly higher (by 73%) in contrast to remarkably lower GSSG/GSH ratio, approximately 3-fold, compared to controls. These results suggest that NO production or oxidation is activated in SALS patients, leading to a decrease in superoxide radicals to oxidize GSH. The subsequent generation of a highly reactive anion, peroxynitrite, may play a causal role in the pathogenesis of SALS. 相似文献
75.
Tetsuya Murata Shigeo Nakamura Hiroya Kato Yasushi Yatabe Taizo Shiraishi Makoto Kuroda Ryulchi Yatani Taizan Suchi 《Pathology international》1997,47(11):801-805
A case of Hodgkln's disease (HD), lymphocyte depression (LD) type In an Immunosuppressive patient is described. The patient was a 48-year-old male and his parents were born In the Kyushu area, which is an endemic area for adult T cell lymphomaheukemla (ATL). He was seropositive for ATL virus (ATLV, also referred to as HTLV-I) and showed a marked Immunosuppressive condition. He developed LD-HD and Pneumocystis carinii pneumonia, and died due to respiratory failure. The Immunohistochemical and in situ hybridization analyses revealed that the Reed-Sternberglike cells In the lymph node biopsy sample were positive for Ber-H2 (CD30), Leu-M1 (CD15), L-26 (CD20), Bcl-2, p53 and EBER, the viral genome of Epstein-Barr virus (EBV). 相似文献
76.
To provide direct evidence for substantia nigra pars reticulata (SNr) control of oro-facio-lingual muscle activity, high-frequency electrical microstimulation (mainly trains of 20, 333-Hz cathodal pulses at 40-60 microA) and GABA microinjection (1-5 microl of 10 mM GABA in saline) were carried out using a three-barreled microelectrode at the same SNr site in lightly anesthetized, chronically decorticated rats (n=39). Decortication eliminated the possibility that SNr microstimulation might activate corticofugal fibers descending in the adjoining cerebral peduncle. When the most ventral layer of the SNr was approached, high-amplitude electromyographic (EMG) activity of up to 6 mV with a distinctive waveform appeared synchronously with electrical stimuli in the anterior digastric, masseter, genioglossus, and levator labii superioris muscles. This EMG activity was evoked bilaterally, with an ipsilateral predominance. Eye movements, mostly rotation of the eyeball vertically down in the orbit, were noted. Infrequent blinking was also noted. Histologic examination localized the effector site to the middle third of the mediolateral extent of the caudal SNr corresponding to between 5.8 mm (level of the oculomotor nerve) and 6.5mm (caudal end of the SNr) caudal to bregma; and to the ventralmost peripeduncular region of the SNr corresponding to 7.7 mm to 8.0 mm beneath the cortical surface. We referred to this site as the substantia nigra pars reticulata oro-facio-lingual (SNr-ofl) region. GABA injection produced tonic EMG discharge with consistent amplitude in all of the four muscles studied. The GABA effect was negated by a preceding microinjection of the GABA-A receptor antagonist bicuculline, whereas saline control injection had no effect. Changes in amplitude of evoked EMG activity according to location of the stimulating microelectrode reflected somatotopic organization of the SNr-ofl region. This extremely localized electrical and receptor microstimulation in the SNr produced synchronized powerful contraction of jaw, tongue, and facial muscles with different neural innervation. These findings advance our understanding of the mechanisms of the SNr concerning oro-facio-lingual movements. 相似文献
77.
Chorioamnionitis decreased incidence of respiratory distress syndrome by elevating fetal interleukin-6 serum concentration 总被引:2,自引:0,他引:2
Shimoya K Taniguchi T Matsuzaki N Moriyama A Murata Y Kitajima H Fujimura M Nakayama M 《Human reproduction (Oxford, England)》2000,15(10):2234-2240
Respiratory distress syndrome (RDS) of newborns is one of the most important factors determining neonatal morbidity and mortality. The interleukin-6 (IL-6) titre in cord sera of RDS-free neonates born to mothers with histological chorioamnionitis was significantly higher than that in RDS-complicated neonates without chorioamnionitis. Maternal administration of glucocorticoid suppressed the IL-6 concentrations in the cord sera of fetuses with chorioamnionitis. The fetuses without chorioamnionitis who suffered from RDS even after maternal glucocorticoid administration showed a similar IL-6 titre to that of RDS-affected neonates without chorioamnionitis. Examination of the mechanism by which IL-6 decreased the incidence of fetal RDS revealed that H441-4, a human pulmonary adenocarcinoma cell line, stimulated with recombinant (r)-IL-6 started the synthesis of mRNA and protein of pulmonary surfactant protein (SP)-A. The present study shows that IL-6 elevation in fetuses with chorioamnionitis promotes fetal lung maturation by inducing SP-A synthesis, thereby decreasing the incidence of RDS in the preterm neonates. 相似文献
78.
79.
Pham HM Konnai S Usui T Chang KS Murata S Mase M Ohashi K Onuma M 《Archives of virology》2005,150(12):2429-2438
Summary. In order to rapidly detect and differentiate Newcastle disease virus (NDV) isolates, a method based on real-time PCR SYBR
Green I melting-curve analysis of the fusion (F) protein gene was developed. The detection limit of real-time PCR was 9 × 102 plasmid copies and was 100 times more sensitive than conventional PCR. Thirty eight reference NDV strains were rapidly identified
by their distinctive melting temperatures (Tms): 89.23 ± 0.27 °C for velogenic strains, 90.17 ± 0.35 °C for pigeon mesogenic strains, 91.25 ± 0.14 °C for two lentogenic
strains (B1 and Ishii). No amplification was detected from unrelated RNA samples by this method. This real-time PCR directly
detected NDV from infected tissues and eliminated the gel electrophoretic step for analyzing PCR product using ethidium bromide.
The total time for a PCR run was less than 1 hour. The results obtained in this study showed that the real-time PCR presented
here is a good screening test for the identification of NDV. 相似文献
80.
Characterization of the murine interleukin 5 receptor by using a monoclonal antibody 总被引:10,自引:0,他引:10
N Yamaguchi Y Hitoshi S Mita Y Hosoya Y Murata Y Kikuchi A Tominaga K Takatsu 《International immunology》1990,2(2):181-187
Murine interleukin 5 (IL-5), a lymphokine produced by helper T cells, is involved in the regulation of growth and differentiation of B cells and other hematopoietic cells. The receptor for IL-5 has been identified as two cross-linked complexes on T88-M cells (a murine IL-5-dependent early B cell line). In this study the IL-5 receptor was directly characterized by utilizing an immobilized IL-5 column and a rat monoclonal antibody, designated H7, directed against the IL-5 receptor. H7 completely inhibited specific binding of 35S-labeled IL-5 to T88-M cells, and bound to IL-5-responsive cells, e.g. T88-M, BCL1-B20 (a chronic B-cell leukemia), and MOPC104E (a myeloma), whereas H7 did not bind to IL-5-non-responsive cells, e.g. X5563 (a myeloma), FDC-P1 (an IL-3-dependent line), and MTH (an IL-2-dependent CTLL). H7 could barely bind to T88-M cells in the presence of IL-5, and immunoprecipitated a major band with an Mr of approximately 60 kd from the extract of surface-radioiodinated T88-M cells. The precipitation of this 60 kd molecule was inhibited by the addition of IL-5. Analysis with immobilized IL-5 also revealed that a 60 kd molecule bound specifically to IL-5-coupled beads compared with control beads. Furthermore, no additional molecule with a higher Mr that was recognized by H7 appeared under non-reducing, compared with reducing, conditions. The 60 kd molecule recognized by H7 could be digested with N-glycanase to yield a protein band of approximately 55 kd.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献