全文获取类型
收费全文 | 1423篇 |
免费 | 65篇 |
国内免费 | 11篇 |
专业分类
耳鼻咽喉 | 6篇 |
儿科学 | 46篇 |
妇产科学 | 26篇 |
基础医学 | 191篇 |
口腔科学 | 13篇 |
临床医学 | 89篇 |
内科学 | 328篇 |
皮肤病学 | 19篇 |
神经病学 | 104篇 |
特种医学 | 32篇 |
外科学 | 269篇 |
综合类 | 8篇 |
预防医学 | 53篇 |
眼科学 | 13篇 |
药学 | 112篇 |
中国医学 | 2篇 |
肿瘤学 | 188篇 |
出版年
2023年 | 6篇 |
2022年 | 26篇 |
2021年 | 53篇 |
2020年 | 30篇 |
2019年 | 24篇 |
2018年 | 36篇 |
2017年 | 29篇 |
2016年 | 26篇 |
2015年 | 26篇 |
2014年 | 49篇 |
2013年 | 43篇 |
2012年 | 88篇 |
2011年 | 108篇 |
2010年 | 60篇 |
2009年 | 47篇 |
2008年 | 82篇 |
2007年 | 100篇 |
2006年 | 82篇 |
2005年 | 80篇 |
2004年 | 64篇 |
2003年 | 56篇 |
2002年 | 60篇 |
2001年 | 35篇 |
2000年 | 31篇 |
1999年 | 24篇 |
1997年 | 10篇 |
1996年 | 5篇 |
1995年 | 5篇 |
1994年 | 12篇 |
1992年 | 27篇 |
1991年 | 24篇 |
1990年 | 17篇 |
1989年 | 15篇 |
1988年 | 13篇 |
1987年 | 14篇 |
1986年 | 13篇 |
1985年 | 10篇 |
1984年 | 5篇 |
1983年 | 5篇 |
1982年 | 4篇 |
1979年 | 7篇 |
1977年 | 5篇 |
1974年 | 4篇 |
1973年 | 7篇 |
1972年 | 2篇 |
1971年 | 7篇 |
1970年 | 4篇 |
1969年 | 2篇 |
1968年 | 2篇 |
1965年 | 3篇 |
排序方式: 共有1499条查询结果,搜索用时 15 毫秒
1.
S Togo 《Nihon Geka Gakkai zasshi》1989,90(7):1009-1018
The proportion of T-lymphocyte subsets of the regional lymph node lymphocytes of 36 gastric cancer patients was analysed using single and two color flow cytometry technique. The antibodies against human T-lymphocyte were anti-CD3, CD4, CD8, CD4 X Leu8, CD4 X 4B4 and CD8 X CD11. The results were as follows. 1) Using single color analysis, the proportion of CD3+ and CD4+ cells in the metastatic lymph node was decreased and that of CD8+ cells was not changed compared with the non-metastatic lymph node. Therefore, the ratio of CD4 to CD8 was reduced. Using two color analysis, proportion of CD4+ Leu8- cells and CD4+ 4B4- cells was reduced. On the contrary, that of CD8+ CD11+ cells was increased in the metastatic lymph node compared with the non-metastatic lymph node. 2) The proportion of CD3+, CD4+ and CD4+ 4B4- cells was decreased in the non-metastatic lymph node of patients with lymph node metastasis compared with that of patients without lymph node metastasis. 3) The proportion of T-lymphocyte subsets was not changed in the metastatic lymph node, whether the volume including cancer cell is much or not. These results suggest that the metastatic lymph node was less defensive against lymph node metastasis in the gastric cancer. 相似文献
2.
The intracellular pH of rat peritoneal mast cells was slightly acidic and compound 48/80 induced a decrease in the cytoplasmic pH of these cells. By means of chemical skinning, it was revealed that perfusion with Ca2+ or inositol 1,4,5-trisphosphate (IP3) induced degranulation dose-dependently in mast cells at concentrations higher than 10 microM and 0.1 microM, respectively. Na+ was essential for the release of histamine from mast cells. An assay based on the binding of 45Ca to mast cell fragments revealed that the intracellular Ca store of the mast cell is located in the endoplasmic reticulum. IP3 liberated Ca from the endoplasmic reticulum. 相似文献
3.
K Tasaka M Akagi K Izushi M Mio 《Methods and findings in experimental and clinical pharmacology》1990,12(8):531-539
Astemizole (0.5-5 mg/kg, p.o.) dose-dependently inhibited heterologous and homologous PCA reactions in rats at ID50 values of 1.48 mg/kg and 2.37 mg/kg, respectively. The inhibitory effect of astemizole on heterologous PCA was most remarkable when this compound was given p.o. 2 h prior to antigen challenge. Astemizole (0.1-5 mg/kg, p.o.) dose-dependently inhibited experimentally-induced asthma in guinea pigs at an ID50 of 0.86 mg/kg. Ex vivo, astemizole (0.5-5 mg/kg, p.o.) inhibited antigen-induced histamine release from lung pieces of sensitized guinea pigs. In in vitro experiments, the drug dose-dependently inhibited antigen-induced histamine and SRS-A releases from guinea pig lung pieces at concentrations of 0.05-10 microM. Furthermore, astemizole (0.1-10 microM) inhibited the histamine release induced by compound 48/80 and antigen-antibody reaction from rat peritoneal mast cells, and at 0.1-500 nM inhibited both leukotriene C4- and platelet-activating factor (PAF)-induced contraction of isolated guinea pig trachea at submicromolar concentrations. Astemizole not only inhibited 45Ca uptake into rat mast cells but also prevented the Ca2+ release from the intracellular Ca store induced by compound 48/80, although this compound did not affect the histamine release from permeabilized mast cells induced by Ca2+. Our results suggest that one of the antiallergic mechanisms of astemizole may be an inhibition of signal transduction from the mast cell membrane to the intracellular systems. 相似文献
4.
Bronchial responsiveness and acute bronchodilator response in chronic obstructive pulmonary disease and diffuse panbronchiolitis. 总被引:2,自引:2,他引:0 下载免费PDF全文
BACKGROUND--Diffuse panbronchiolitis (DPB) is characterised clinically by chronic airflow limitation and respiratory tract infection, and pathologically by chronic bronchiolar inflammation. To elucidate the functional differences between chronic obstructive pulmonary disease (COPD) and DPB the bronchial responsiveness to methacholine was compared in 64 patients with COPD and 32 patients with DPB, and the bronchodilator response was compared in 72 patients with COPD and 49 with DPB. METHODS--Bronchial responsiveness to methacholine was determined by the dosimeter method and expressed as PD20FEV1, and bronchodilator response was measured as the change in percentage predicted response with 5 mg nebulised salbutamol. RESULTS--Baseline FEV1 was similar in the two groups of patients. Patients with COPD were more responsive to methacholine than were those with DPB (geometric mean PD20FEV1 8.87 v 48.0 cumulative units). Reversibility of air flow obstruction, expressed as the difference between the percentage predicted postbronchodilator FEV1 and prebronchodilator FEV1, was significantly larger in patients with COPD than in those with DPB (7.87 (6.52)% v 4.16 (4.43)%). CONCLUSIONS--The observation that patients with DPB differ substantially in bronchial responsiveness from those with COPD is thought to reflect the difference in the mechanisms of these two diseases--that is, airway disease in DPB and more parenchymal disease in the group of patients with COPD. The nature of bronchiolar inflammation in COPD and DPB is also different, possibly explaining the difference in bronchial responsiveness. More fixed airflow limitation as a result of structural bronchiolar lesions in DPB will explain the smaller reversibility of airflow obstruction. 相似文献
5.
M Kuriyama Y Hokezu S Togo K Nagata K Takahashi T Igakura M Osame 《Nihon Ronen Igakkai zasshi. Japanese journal of geriatrics》1992,29(7-8):559-564
Serum lipid, lipoprotein, apolipoprotein, and sterol profiles were studied in 22 patients with senile dementia of the Alzheimer type (SDAT) and 29 patients with vascular dementia (VD). Levels of high density lipoprotein-cholesterol (HDL-C) were lower in both patients groups of SDAT and VD than in control group. Apolipoprotein AI and AII are two major proteins in HDL. In this study, apolipoprotein AI levels were normal, but apolipoprotein AII levels were lower in the patient groups, especially in the VD group, than in the control group. Lipoprotein(a) levels were higher in both patient groups, especially in the VD group. There were no differences of cholesterol, cholesterol precursors (desmosterol and lathosterol), and plant sterols (campesterol and beta-sitosterol) among the three groups. Murine apolipoprotein AII is a serum precursor of murine senile amyloid protein, and the apolipoprotein AII variant with proline-->glutamine substitution at position 5 in the serum of accelerated senescence-prone mice is identical to the murine senile amyloid fibril protein from amyloid-deposited tissues of these mice. In human SDAT and VD, the reason for the low level of apolipoprotein AII remains unclear. 相似文献
6.
7.
Pharmacologic preconditioning effects: Prostaglandin E1 induces heat-shock proteins immediately after ischemia/reperfusion of the mouse liver 总被引:1,自引:0,他引:1
Ken-ichi Matsuo M.D. Shinji Togo M.D. Ph.D. Hitoshi Sekido M.D. Ph.D. Tomoyuki Morita M.D. Ph.D. Masako Kamiyama Ph.D. Daisuke Morioka M.D. Ph.D. Toru Kubota M.D. Ph.D. Yasuhiko Miura M.D. Ph.D. Kuniya Tanaka M.D. Ph.D. Takashi Ishikawa M.D. Ph.D. Yasushi Ichikawa M.D. Ph.D. Itaru Endo M.D. Ph.D. Hitoshi Goto M.D. Ph.D. Hiroyuki Nitanda M.D. Ph.D. Yasushi Okazaki M.D. Ph.D. Yoshihide Hayashizaki M.D. Ph.D. Hiroshi Shimada M.D. Ph.D. 《Journal of gastrointestinal surgery》2005,9(6):758-768
Prostaglandin E1 (PGE1) has several potential therapeutic effects, including cytoprotection, vasodilation, and inhibition of platelet aggregation. This study investigates the protective action of PGE1 against hepatic ischemia/reperfusion injury in vivo using a complementary DNA microarray. PGE1 or saline was continuously administered intravenously to mice in which the left lobe of the liver was made ischemic for 30 minutes and then reperfused. Livers were harvested 0, 10, and 30 minutes postreperfusion. Messenger RNA was extracted, and the samples were labeled with two different fluorescent dyes and hybridized to the RIKEN set of 18,816 full-length enriched mouse complementary DNA microarrays. Serum alanine aminotransferase and aspartate aminotransferase levels at 180 minutes postreperfusion were significantly lower in the PGE1-treated group than in the saline-treated group. The cDNA microarray analysis revealed that the genes encoding heat-shock protein (HSP) 70, glucose-regulated protein 78, HSP86, and glutathione S-transferase were upregulated at the end of the ischemic period (0 minutes postreperfusion) in the PGE1 group. Our results suggested that PGE1 induces HSPs immediately after ischemia reperfusion. HSPs might therefore play an important role in the protective effects of PGE1 against ischemia/reperfusion injury of the liver. 相似文献
8.
Hiroshi Shimada Masao Nanko Shoichi Fujii Hidenobu Masui Shinji Togo Hideyuki Ike Akira Nakano Shigeo Ohki 《Journal of Hepato-Biliary-Pancreatic Surgery》1995,2(2):116-121
Hepatic micrometastases of the parenchyma adjacent to a macroscopic lesion were detected in 17 of 31 resected liver metastases.
Fifty-nine micrometastatic lesions were detected in total; 26 lesions were situated in the portal vein (PV), 22 in the central
vein (CV), 5 in the bile duct (BD), and 6 in the sinusoid (SS). A histological study confirmed the direct invasion of the
macrometastatic cancer cells into the adjacent PV, CV, BD, and SS. According to the tumor doubling time, the mean diameter
of the macrometastases in 19 remnant livers was calculated to have been 0.57±0.87 cm at the time of the primary resection.
The calculated diameter of 3 of these 19 macrometastases was found to be less than 0.01 cm, the minimum implantable size,
indicating that the cancer recurrence in these specimens may have developed from macroscopic metastatic lesions as a satellite,
and not from the primary tumor. In 13 patients who received doses of 5250 mg or more of 5 fluorouracil (FU) via the hepatic
artery, the cumulative disease-free rate 2 years postoperatively was 100%; this value was 47.6% in 11 patients who received
less than 5250 mg of 5 FU via the hepatic artery, and 0% in 39 patients who received no chemotherapy (P<0.005). These results suggest that anatomical hepatic resection for satellite lesions, combined with prophylactic hepatic
arterial chemotherapy for micrometastases, decreases the recurrence rate of hepatic metastases in the remnant liver. 相似文献
9.
In order to study the role of the cytoskeleton in histamine release from mast cells, the effects of cytochalasin D, cholchicine and vinblastine on Ca2+ release from the intracellular Ca store induced by compound 48/80 were investigated by means of a video-intensified microscopy system. When the quin 2-loaded mast cells were stimulated by 0.35 g/ml of compound 48/80, a rapid increase in intracellular Ca2+ was observed. At concentrations higher than 10–6
M, both colchicine and vinblastine pretreatments significantly inhibited the increase in intracellular Ca2+ concentrations caused by compound 48/80, although cytochalasin D had no effect. When permeabilized mast cells were exposed to potassium-antimonate solution, microtubules became attached to the endoplasmic reticulum, where many dots of Ca-antimonate were observed; in some areas, the microtubules interconnected the endoplasmic reticulum and granules in the mast cells. From the results of the present study, it was assumed that microtubules play some important role in the processes leading to Ca2+ release from the intracellular Ca store. 相似文献
10.
Jared Liu Hsin-Wen Chang Zhi-Ming Huang Mio Nakamura Sahil Sekhon Richard Ahn Priscila Munoz-Sandoval Shrishti Bhattarai Kristen M. Beck Isabelle M. Sanchez Eric Yang Mariela Pauli Sarah T. Arron Wai-Ping Fung-Leung Ernesto Munoz Xuejun Liu Tina Bhutani Jeffrey North Wilson Liao 《The Journal of allergy and clinical immunology》2021,147(6):2370-2380