全文获取类型
收费全文 | 6772篇 |
免费 | 268篇 |
国内免费 | 28篇 |
专业分类
耳鼻咽喉 | 65篇 |
儿科学 | 169篇 |
妇产科学 | 116篇 |
基础医学 | 743篇 |
口腔科学 | 129篇 |
临床医学 | 337篇 |
内科学 | 1529篇 |
皮肤病学 | 69篇 |
神经病学 | 661篇 |
特种医学 | 160篇 |
外科学 | 1196篇 |
综合类 | 26篇 |
预防医学 | 198篇 |
眼科学 | 214篇 |
药学 | 509篇 |
中国医学 | 19篇 |
肿瘤学 | 928篇 |
出版年
2023年 | 42篇 |
2022年 | 75篇 |
2021年 | 103篇 |
2020年 | 75篇 |
2019年 | 109篇 |
2018年 | 121篇 |
2017年 | 92篇 |
2016年 | 131篇 |
2015年 | 113篇 |
2014年 | 147篇 |
2013年 | 190篇 |
2012年 | 286篇 |
2011年 | 334篇 |
2010年 | 205篇 |
2009年 | 160篇 |
2008年 | 354篇 |
2007年 | 320篇 |
2006年 | 391篇 |
2005年 | 416篇 |
2004年 | 436篇 |
2003年 | 430篇 |
2002年 | 416篇 |
2001年 | 165篇 |
2000年 | 144篇 |
1999年 | 161篇 |
1998年 | 127篇 |
1997年 | 89篇 |
1996年 | 85篇 |
1995年 | 66篇 |
1994年 | 63篇 |
1993年 | 66篇 |
1992年 | 123篇 |
1991年 | 112篇 |
1990年 | 115篇 |
1989年 | 93篇 |
1988年 | 70篇 |
1987年 | 69篇 |
1986年 | 60篇 |
1985年 | 41篇 |
1984年 | 50篇 |
1983年 | 50篇 |
1982年 | 33篇 |
1981年 | 21篇 |
1980年 | 23篇 |
1979年 | 31篇 |
1977年 | 28篇 |
1976年 | 26篇 |
1975年 | 21篇 |
1973年 | 21篇 |
1972年 | 24篇 |
排序方式: 共有7068条查询结果,搜索用时 15 毫秒
1.
Shoji Kubo Hiroaki Kinoshita Kazuhiro Hirohashi Takatsugu Yamamoto 《Journal of Hepato-Biliary-Pancreatic Surgery》1995,2(1):85-89
A case of cystadenocarcinoma of the liver is reported. The patient was a 73-year-old woman in whom a tumor was detected in
the lateral segment of the liver during a health examination. Ultrasonograms and computed tomograms showed a multilocular
cystic mass. Magnetic resonance imaging (MRI) showed a multilocular lowintensity mass, including a high-intensity portion
and a portal branch compressed by the tumor. MRI with gadolinium showed an enhanced cyst wall. The cystic part of the tumor
became smaller and the solid part became larger over a 1-month period, indicating that the tumor was malignant. Subsegmentectomy
(S3) was performed and cystadenocarcinoma with cystadenoma was diagnosed by histopathological examination. Identification of
changes in the appearance of a tumor should be helpful for the differential diagnosis of cystadenoma and cystadenocarcinoma. 相似文献
2.
Yuki Izawa Masanori Yoshizumi Keisuke Ishizawa Yoshiko Fujita Shuji Kondo Shoji Kagami Kazuyoshi Kawazoe Koichiro Tsuchiya Shuhei Tomita Toshiaki Tamaki 《Hypertension research》2007,30(11):1107-1117
Big mitogen-activated protein kinase 1 (BMK1), also known as extracellular signal-regulated kinase 5 (ERK5), is a newly identified member of the mitogen-activated protein (MAP) kinase family. Recently, several studies have suggested that BMK1 plays an important role in the pathogenesis of cardiovascular disease. To clarify the pathophysiological significance of BMK1 in the process of vascular remodeling, we explored the molecular mechanisms of BMK1 activation in vascular smooth muscle cells (VSMCs). From the results of co-immunoprecipitation and immunoblotting analyses, it was found that platelet-derived growth factor (PDGF), a known potent mitogen, activated BMK1 and triggered the Gab1-SHP-2 interaction in rat aortic smooth muscle cells (RASMCs). The abrogation of SHP-2 phosphatase activity by transfection of the SHP-2-C/S mutant suppressed PDGF-stimulated BMK1 activation. Infection with an adenoviral vector expressing dominant-negative MEK5alpha, which can suppress PDGF-stimulated BMK1 activation to the control level, inhibited PDGF-induced RASMC migration. Moreover, we observed an increase of BMK1 activation in injured mouse femoral arteries. From these findings, it is suggested that BMK1 activation leads to VSMC migration induced by PDGF via Gab1-SHP-2 interaction, and that BMK1-mediated VSMC migration may play a role in the pathogenesis of vascular remodeling. 相似文献
3.
Masafumi Fujimoto Tuneaki Sakata Yuji Tsuruta Shoji Iwagami Hiroshi Teraoka Shin-ichi Mihara Yonetaka Fukiishi Misao Ide 《Biochemical pharmacology》1990,40(12):2661-2670
Bradykinin-stimulated prostacyclin synthesis in porcine aortic endothelial cells was enhanced by pretreatment of the cells with pertussis toxin or islet-activating protein (IAP) for 5 hr or longer. Although ADP-ribosylation of a protein with a molecular weight of 41–42 kD in the cell membranes was completed by 3 hr after the addition of IAP into the incubation medium, there was good correlation between enhancement of bradykinin-induced prostacyclin synthesis and ADP-ribosylation of the IAP substrate over a wide range of IAP concentrations. Furthermore, even if IAP was removed from the incubation medium at 3 hr, bradykinin-induced prostaglandin synthesis at 24 hr was still potentiated. Cycloheximide and actinomycin D enhanced bradykinin-induced prostacyclin synthesis and apparently blocked the effect of IAP. Since this result suggested the involvement of an inhibitor protein(s) of prostacyclin synthesis in the IAP effect, we studied the effect of IAP on the level of lipocortin I which is known to inhibit phospholipase A2. Western and Northern blot analyses revealed that IAP decreased the amounts of protein and mRNA of lipocortin I. These results suggest that the enhancement of bradykinin-induced prostacyclin synthesis by IAP is associated with a decrease in the level of lipocortin I. 相似文献
4.
In fetal rats whose dams were fed a low-protein diet, 35S sulfate uptake into the growth plate of the long bone and rib was higher than in the control group. The elution pattern of guanidine-HCl extract in gel chromatography revealed that the malnourished group had more high molecular weight proteoglycans in the dissociative condition and a larger aggregated portion in the associative condition than did the control group; however, the same chondroitin-sulfate chain size existed. Calcium content did not differ in both groups. Aggregated proteoglycan or a high molecular weight proteoglycan that existed in the malnourished group probably played an inhibitory role in calcification. Prenatal protein-energy malnutrition may delay the change of proteoglycan character, which could affect mineralization of fetal bones. 相似文献
5.
Shoji Matsushima Yuko Sakai Yoshiki Hira Masamichi Kato Tsukasa Shigemitsu Yoichi Shiga 《Journal of pineal research》1993,14(3):145-150
Abstract: Light microscopic observations on the superficial pineal gland of Wistar-King rats were made to examine whether or not pineal volume and pinealocyte size, expressed as nuclear density, at daytime or nighttime are affected by long-term exposure to 50 Hz rotating magnetic field (MF) at 5.0 μT. Determinations of pineal volume and pinealocyte size were repeated twice (April and October) during the year. Size of pinealocytes in MF-exposed and sham-exposed rats exhibited, in addition to the difference between peripheral and central regions, regional differences in a proximodistal direction; pinealocytes in the distal and middle-peripheral regions were usually larger than those in the proximal and middle-central regions at daytime or nighttime. In October, distal and proximal pinealocytes showed significant day-night changes in size in sham-exposed rats, but not in MF-exposed animals. The situations in the two groups were almost reversed in April. Significant day-night differences were scarcely found in pinealocyte size in the middle region in the two groups. Throughout the study, pineal volume and pinealocyte size in each region were generally the same between MF-exposed and sham-exposed rats at daytime or nighttime. The results suggest that pinealocytes in the distal and proximal regions, but not those in the middle region, are affected by MF-exposure; day-night differences in sizes of distal and proximal pinealocytes appear in April and disappear in October under the influence of MF. MF may exert an effect on mechanisms controlling day-night rhythms of pinealocyte size in the rat. 相似文献
6.
Shoji Sunada Masahiko Miyata Yasuhiro Tanaka Kenzo Okumura Makoto Nakamuro Toru Kitagawa Ryota Shirakura Yasunaru Kawashima 《Surgery today》1992,22(1):74-77
An aggressive pancreatectomy was performed on a 53 year old Japanese man with advanced cancer of the pancreas. The tumor originated from the body of the pancreas and invaded the stomach, duodenum, left kidney, transverse colon and common hepatic artery. An unexpected cancer was also found in the head of the pancreas during the operation. Therefore, total pancreatectomy, total gastrectomy, left adrenonephrectomy, resection of the left transverse colon and dissection of the regional lymph nodes were performed. Resection of the common hepatic artery was also performed, followed by an end-to-end anastomosis between the common hepatic artery and celiac trunk. The postoperative course was uneventful and the patient was doing well until nine months after the operation when multiple metastatic lesions were noted in the liver. He died 391 days after the operation from hepatic failure. 相似文献
7.
Yu-Yan Fan Ryoko Baba Yukiko Nagai Akira Miyatake Naohisa Hosomi Shoji Kimura Guang-Ping Sun Masakazu Kohno Mamoru Fujita Youichi Abe Akira Nishiyama 《Hypertension research》2006,29(3):169-178
Recent studies have suggested that aldosterone plays a role in the pathogenesis of renal injury. In this study, we investigated whether local angiotensin II (Ang II) activity contributes to the progression of renal injury in aldosterone/salt-induced hypertensive rats. Uninephrectomized rats were treated with 1% NaCl in a drinking solution and one of the following combinations for 6 weeks: vehicle (2% ethanol, s.c.; n=9), aldosterone (0.75 mug/h, s.c.; n=8), aldosterone+Ang II type 1 receptor blocker olmesartan (10 mg/kg/day, p.o.; n=8), or aldosterone+olmesartan (100 mg/kg/day, p.o.; n=9). Aldosterone/salt-treated hypertensive rats exhibited severe proteinuria and renal injury characterized by glomerular sclerosis and tubulointerstitial fibrosis. Aldosterone/salt-induced renal injury was associated with augmented expression of angiotensin converting enzyme and Ang II levels in the renal cortex and medullary tissues. Renal cortical and medullary mRNA expression of transforming growth factor-beta (TGF-beta) and connective tissue growth factor (CTGF) as well as the collagen contents were increased in aldosterone/salt-treated hypertensive rats. Treatment with olmesartan (10 or 100 mg/kg/day) had no effect on blood pressure but attenuated proteinuria in a dose-dependent manner. Olmesartan at 10 mg/kg/day tended to decrease renal cortical and medullary Ang II levels, TGF-beta and CTGF expression, and collagen contents; however, these changes were not significant. On the other hand, an ultrahigh dose of olmesartan (100 mg/kg/day) significantly decreased these values and ameliorated renal injury. These data suggest that augmented local Ang II activity contributes, at least partially, to the progression of aldosterone/salt-dependent renal injury. 相似文献
8.
Clinical Evaluation of a New Type of Centrifugal Pump 总被引:2,自引:0,他引:2
J. Ninomiya T. Shoji S. Tanaka M. Ikeshita M. Ochi S. Yamauchi T. Yajima H. Yamauchi T. Sugimotox T. Aizawa 《Artificial organs》1994,18(9):702-705
Abstract: The major problems with existing centrifugal pumps are leakage, mechanical trauma, and thrombus formation. In consideration of these problems, a new compact centrifugal pump system was developed. The purpose of this study was to evaluate the new centrifugal pump system clinically. Ten patients underwent open heart surgery with a centrifugal pump or a roller pump. During surgery, hemodynamic and hematological data were obtained. A pulsatile assist device in the pump circuit was used in patients with severe heart disease. There was neither operative death nor hospital mortality, and there was no difference with regard to hemodynamic data between the two groups. The centrifugal pump group, however, had significantly lower hemolysis, especially during prolonged cardiopulmonary bypass. This centrifugal pump could also create sufficient pulsatile flow with a pulsatile assist device. Postoperative macroscopic and microscopic findings demonstrated the smooth surface of the pump without thrombus formation. This centrifugal pump system might be useful for prolonged cardiopulmonary bypass. 相似文献
9.
M Kusunoki Y Shoji Y Sakanoue H Yanagi S Fujita T Yamamura J Utsunomiya 《The Journal of surgical research》1991,51(4):293-296
The effect of gamma-aminobutyric acid (GABA) on the human internal anal sphincter was investigated. Cumulative applications of GABA produced concentration-dependent contractions (10(-8)-10(-5) M) of the isolated human sphincter. Pretreatment with bicuculline (GABAA antagonist) turned them to relaxation. Muscimol, a GABAA agonist, induced concentration-dependent contractions (10(-8)-10(-5) M); however, baclofen (GABAB agonist, 10(-8)-10(-5) M) promoted concentration-dependent relaxation of the strips. These results suggested that both excitatory GABAA receptors and inhibitory GABAB receptors exist in the internal anal sphincter. Oral administration of sodium valproate (1600 mg/day), a GABA transaminase inhibitor, enhanced the anal canal resting pressure in 10 normal volunteers. Anal manometry showed a significant elevation in tonus without affecting amplitudes or frequencies. These results indicated that endogenous GABA, which was increased by sodium valproate, produced elevations in the anal canal resting pressure through its specific receptors in the human internal anal sphincter. 相似文献