全文获取类型
收费全文 | 4210篇 |
免费 | 250篇 |
国内免费 | 8篇 |
专业分类
耳鼻咽喉 | 79篇 |
儿科学 | 97篇 |
妇产科学 | 78篇 |
基础医学 | 650篇 |
口腔科学 | 81篇 |
临床医学 | 312篇 |
内科学 | 907篇 |
皮肤病学 | 88篇 |
神经病学 | 363篇 |
特种医学 | 144篇 |
外科学 | 582篇 |
综合类 | 24篇 |
预防医学 | 195篇 |
眼科学 | 87篇 |
药学 | 308篇 |
中国医学 | 14篇 |
肿瘤学 | 459篇 |
出版年
2023年 | 25篇 |
2022年 | 39篇 |
2021年 | 81篇 |
2020年 | 40篇 |
2019年 | 75篇 |
2018年 | 80篇 |
2017年 | 59篇 |
2016年 | 90篇 |
2015年 | 95篇 |
2014年 | 113篇 |
2013年 | 138篇 |
2012年 | 242篇 |
2011年 | 243篇 |
2010年 | 159篇 |
2009年 | 113篇 |
2008年 | 180篇 |
2007年 | 213篇 |
2006年 | 207篇 |
2005年 | 241篇 |
2004年 | 226篇 |
2003年 | 205篇 |
2002年 | 204篇 |
2001年 | 128篇 |
2000年 | 111篇 |
1999年 | 123篇 |
1998年 | 42篇 |
1997年 | 44篇 |
1996年 | 44篇 |
1995年 | 33篇 |
1994年 | 27篇 |
1993年 | 25篇 |
1992年 | 77篇 |
1991年 | 56篇 |
1990年 | 70篇 |
1989年 | 67篇 |
1988年 | 63篇 |
1987年 | 64篇 |
1986年 | 62篇 |
1985年 | 50篇 |
1984年 | 49篇 |
1983年 | 34篇 |
1982年 | 31篇 |
1979年 | 24篇 |
1978年 | 15篇 |
1977年 | 22篇 |
1975年 | 10篇 |
1973年 | 14篇 |
1971年 | 14篇 |
1970年 | 13篇 |
1969年 | 26篇 |
排序方式: 共有4468条查询结果,搜索用时 15 毫秒
41.
42.
H Tachibana K Kawabata M Takeda M Sugita J Kondo M Miyauchi A Matsuoka 《Rinsho byori. The Japanese journal of clinical pathology》1991,39(9):999-1004
Short-latency somatosensory (SSEPs), brainstem auditory evoked potentials (BAEPs) and event-related potentials (ERPs) were studied in 7 patients with Binswanger's encephalopathy, 12 patients with Alzheimer's disease and 17 normal subjects. Patients with Binswanger's encephalopathy showed significantly prolonged central conduction time (CCT) and P300 latency, and prolonged tendency of I-V IPL compared to those of normal subjects. In particular, CCT showed significant prolongation compared to that of patients with Alzheimer's disease. In patients with Alzheimer's disease, I-V IPL and P300 latency were significantly prolonged compared to those of normals although there was no significant difference in CCT between Alzheimer's disease and normal subjects. These results indicate some difference between Binswanger's encephalopathy and Alzheimer's disease from the electrophysiological aspects although both of these entities are characterized by progressive mental deterioration. 相似文献
43.
Yoshinori Seko Shigeru Ishiyama Toshiro Nishikawa Takeshi Kasajima Michiaki Hiroe Shin Suzuki Sugao Ishiwata Sachio Kawai Yuetsu Tanaka Miyuki Azuma Tetsuji Kobata Hideo Yagita Ko Okumura Ryozo Nagai 《Cardiovascular pathology》2002,11(3):166-170
BACKGROUND: T-cell-mediated myocardial damage is known to be involved in acute myocarditis and dilated cardiomyopathy. Recently, we found that tumor necrosis factor (TNF) ligand superfamily costimulatory molecules, especially 4-1BBL, played an important role in the myocardial damage of murine acute viral myocarditis. METHODS AND RESULTS: To investigate the roles for CD27L, CD30L, OX40L and 4-1BBL, which belong to TNF ligand superfamily, in the development of acute myocarditis and dilated cardiomyopathy, we analyzed the expression of these antigens in the myocardial tissues of patients with acute myocarditis and dilated cardiomyopathy. We also examined expression of the receptors for these molecules, CD27, CD30, OX40 and 4-1BB, which belong to TNF receptor superfamily, on the infiltrating cells. Strong expression of CD27L, CD30L and 4-1BBL and weak to moderate expression of OX40L was found in the cardiac myocytes of patients with acute myocarditis. Moderate expression of CD27L, CD30L and 4-1BBL and weak expression of OX40L was found on the cardiac myocytes of patients with dilated cardiomyopathy. Most of the infiltrating cells expressed CD27, CD30 and 4-1BB and a part of the infiltrating cells expressed OX40. CONCLUSIONS: Our findings suggest that expression of TNF ligand superfamily costimulatory molecules on cardiac myocytes may play a role in the cell-mediated myocardial damage in patients with acute myocarditis and dilated cardiomyopathy as in murine viral myocarditis. 相似文献
44.
The neurons in the external segment of the pallidum (GPe) in awake animals maintain a high level of firing activity. The level and pattern of the activity change with the development of basal ganglia disorders including parkinsonism and hemiballism. The GPe projects to most of the nuclei in the basal ganglia. Thus exploring the mechanisms controlling the firing activity is essential for understanding basal ganglia function in normal and pathological conditions. To explore the role of ionotropic glutamatergic and GABAergic inputs to the GPe, unit recordings combined with local injections of receptor antagonists were performed in awake monkeys. Observations on the effects of local application of the alpha-amino-3-hydroxy-5-methylisoxazole-4-propionic acid (AMPA)/kainate antagonist 1,2,3,4-tetrahydro-6-nitro-2, 3-dioxo-benzo[f]quinoxaline-7-sulfonamide, the N-methyl-D-aspartic acid (NMDA) antagonist 3-(2-carboxypiperazin-4-yl)-propyl-1-phosphonic acid, and the GABAA antagonist gabazine as well as the effects of muscimol blockade of the subthalamic nucleus on the spontaneous firing rate, firing patterns, and cortical stimulation induced responses in the GPe suggested the following: sustained glutamatergic and GABAergic inputs control the level of the spontaneous firing of GPe neurons; both AMPA/kainate and NMDA receptors are activated by glutamatergic inputs; some GPe neurons receive glutamatergic inputs originating from areas other than the subthalamic nucleus; no GPe neurons became silent after a combined application of glutamate and GABA antagonists, suggesting that GPe neurons have intrinsic properties or nonionotropic glutamatergic tonic inputs that sustain a fast oscillatory firing or a combination of a fast and a slow oscillatory firing in GPe neurons. 相似文献
45.
Frequent co-localization of Cox-2 and laminin-5 gamma2 chain at the invasive front of early-stage lung adenocarcinomas 总被引:7,自引:0,他引:7
Niki T Kohno T Iba S Moriya Y Takahashi Y Saito M Maeshima A Yamada T Matsuno Y Fukayama M Yokota J Hirohashi S 《The American journal of pathology》2002,160(3):1129-1141
Laminin-5 is an extracellular matrix protein that plays a key role in cell migration and tumor invasion. Cox-2 is an induced isoform of cyclooxygenases that plays an important role in carcinogenesis, suppression of apoptosis, angiogenesis, and metastasis of colon cancer. We report frequent co-expression of cox-2 and laminin-5 at the invasive front of early-stage lung adenocarcinomas. We investigated the expression of cox-2 and laminin-5 immunohistochemically in 102 cases of small-sized lung adenocarcinoma (maximum dimension, 2 cm or less). Cox-2 and laminin-5 were expressed in 97 (95.1%) and 82 (80.4%) cases, respectively. Both were preferentially localized in cancer cells at the cancer-stroma interface, although cox-2 tended to show a diffuse staining pattern in some cases. A comparison of their staining patterns revealed a striking similarity in their distribution in 24 cases, and a partial overlap between their localization in another 20 cases. Moreover, an overall correlation was found between the expression levels of cox-2 and laminin-5 (P = 0.018). To gain insight into the mechanisms that regulate the expression of these proteins, we additionally studied their expression in 58 cases of stage I lung adenocarcinoma, in which p53 status was determined by immunohistochemistry, polymerase chain reaction-single strand conformation polymorphism analysis, and direct sequencing. The results showed that tumors with mutant p53 tended to express more cox-2 than those with wild-type p53 (P = 0.080). Also, tumors that overexpressed p53 had higher levels of cox-2 and laminin-5 than those without p53 overexpression (P = 0.032 and 0.047, respectively). Further immunohistochemical analysis showed that tumors that overexpressed both epidermal growth factor receptor (EGFR) and erbB-2 had higher levels of cox-2 and laminin-5 than those without concomitant overexpression of these proteins (P = 0.014 and P = 0.018, respectively). To see whether EGFR signaling is involved in cox-2 and laminin-5 expression, we further conducted in vitro analyses using six lung adenocarcinoma cell lines (A549, HLC-1, ABC-1, LC-2/ad, VMRC-LCD, and L27). Western blot analyses showed that cox-2 mRNA levels, and to a lesser extent laminin-5 gamma2 mRNA levels, correlated with the expression levels of erbB-2 and the phosphorylated form of MAPK/ERK-1/2 protein. The addition of transforming growth factor-alpha increased both cox-2 and laminin-5 gamma2 mRNA levels in A549, ABC-1, and L27 with different kinetics; the induction of cox-2 occurred earlier than that of laminin-5 gamma2. Finally, the migration of ABC-1 cells was inhibited by MAP kinase kinase inhibitor PD98059 and a selective cox-2 inhibitor NS-398. In contrast, the migration of A549 cells was inhibited by PD98059, but much less effectively by NS-398. These results suggest that co-stimulatory mechanisms may exist that increase the expression of cox-2 and laminin-5 at the invasive front of lung adenocarcinomas and that EGFR signaling could be one of the mechanisms. Further investigations are warranted concerning the role of cox-2 and laminin-5 in cancer cell invasion and the significance of p53 and EGFR signaling in the regulation of cox-2 and laminin-5 expression. 相似文献
46.
Hamada K Sasaki T Koni PA Natsui M Kishimoto H Sasaki J Yajima N Horie Y Hasegawa G Naito M Miyazaki J Suda T Itoh H Nakao K Mak TW Nakano T Suzuki A 《Genes & development》2005,19(17):2054-2065
PTEN is an important tumor suppressor gene. Hereditary mutation of PTEN causes tumor-susceptibility diseases such as Cowden disease. We used the Cre-loxP system to generate an endothelial cell-specific mutation of Pten (Tie2CrePten) in mice. Tie2CrePten(flox/+) mice displayed enhanced tumorigenesis due to an increase in angiogenesis driven by vascular growth factors. This effect was partially dependent on the PI3K subunits p85alpha and p110gamma. In vitro, Tie2CrePten(flox/+) endothelial cells showed enhanced proliferation/migration. Tie2CrePten(flox/flox) mice died before embryonic day 11.5 (E11.5) due to bleeding and cardiac failure caused by impaired recruitment of pericytes and vascular smooth muscle cells to blood vessels, and of cardiomyocytes to the endocardium. These phenotypes depend strongly on p110gamma rather than on p85alpha and were associated with decreased expression of Ang-1, VCAM-1, connexin 40, and ephrinB2 but increased expression of Ang-2, VEGF-A, VEGFR1, and VEGFR2. Pten is thus indispensable for normal cardiovascular morphogenesis and post-natal angiogenesis, including tumor angiogenesis. 相似文献
47.
Preparation of Recombinant Human Monoclonal
Antibody Fab Fragments Specific for Entamoeba
histolytica
下载免费PDF全文
![点击此处可从《Clinical and Vaccine Immunology : CVI》网站下载免费的PDF全文](/ch/ext_images/free.gif)
48.
Expression of cytoplasmic TFF2 is a marker of tumor metastasis and negative prognostic factor in gastric cancer 总被引:8,自引:0,他引:8
Dhar DK Wang TC Maruyama R Udagawa J Kubota H Fuji T Tachibana M Ono T Otani H Nagasue N 《Laboratory investigation; a journal of technical methods and pathology》2003,83(9):1343-1352
Trefoil factor family 2 (TFF2) is a small peptide constitutively expressed in the gastric mucosa, where it plays a protective role in restitution of gastric mucosa. TFF2 has also been shown to be expressed in some gastric cancers, but its role in tumor metastasis and patient prognosis has not been examined. In this study, we examined TFF2 expression at both the mRNA and protein levels and correlated these results with the clinicopathologic characteristics and prognosis of gastric cancer patients. Among the 144 curatively resected samples, 43 (30%) were positive for TFF2. TFF2 expression was preferentially observed in the infiltrating tumor cells sparing the superficial cells. Significantly increased expression of TFF2 was noted in large tumors of the diffuse type. An increased prevalence of TFF2 expression was also found in tumors with advanced T and N stage and in patients with lymphatic and venous invasion. Accordingly, patients with TFF2-expressing tumors had a significantly worse disease-free survival, and in multivariate analysis, this finding remained significant as an independent prognostic factor. Taken together, our results suggest that TFF2 expression may play a role in gastric cancer invasion and as such could be a useful target for therapeutic intervention. 相似文献
49.
F Tachibana H Hakozaki K Takahashi M Kojima S Enomoto J Wada 《Acta pathologica japonica》1979,29(1):73-97
A case of the syndrome of sea-blue histiocyte is presented in a 53-year-old Japanese woman, which is the first recorded case in Japan. The patient had hepatosplenomegaly, bleeding manifestations, mild thrombocytopenia, fatty metamorphosis and cirrhosis of the liver, as well as abnormal serum lipid profiles. Her parents were consanguineous and her maternal grandmother with hepatomegaly died of hepatic failure. Histologically, peculiar histiocytes containing numerous, intracytoplasmic sea-blue stained granules on May-Giemsa stain were demonstrated in biopsy materials of the bone marrow, lymph node and liver. The sea-blue granules in these histiocytes proved to have histochemical staining characteristics of lipogenic ceroid-like pigment. Ultrastructurally, these granules showed membrane-bound, pleomorphic inclusions of heterogeneous nature, including electron-dense amorphous or variegatedly osmiophilic, frequently laminated materials. Enzyme cytochemically, localization of acid phosphatase activity was demonstrated in and around the intracytoplasmic inclusions. With regard to the pathogenesis of the sea-blue histiocytes in this case, it may be suggested that the existence of the abnormality in lipid metabolism plays an important role in intralysosomal ceroidogenesis in these histiocytes. 相似文献
50.
Hideo Sakuma Naoyoshi Mori Mizu Kojima Takeo Saito Fuminori Tachibana Makoto Naito 《Pathology international》1984,34(5):1157-1166
A case with lymphadenopathy of the left side of the neck in a 38-year-old male is described. He had a history of several relapses of about 10 years duration. Swollen lymph nodes were histologically similar to those of the hyaline-vascular type of Castleman's disease, but contained clear-cut lymph sinus and a sheet-like proliferation of plasma cells. Lymph follicles showed proliferation and atrophic germinal centers, in which cellular hypertrophy in the wall of ramifying small blood vessels, called angiosclerosis, was frequently encountered. During its progress, the patient developed plasmacytoma of the lymph nodes with varied clinical manifestations such as polyneuropathy, disturbance of gait, unusual perspiration, hirsuitism, gynecomastia, bilateral papilledema, and albumino-cytologic dissociation in cerebrospinal fluid. 相似文献