全文获取类型
收费全文 | 6213篇 |
免费 | 333篇 |
国内免费 | 33篇 |
专业分类
耳鼻咽喉 | 84篇 |
儿科学 | 182篇 |
妇产科学 | 179篇 |
基础医学 | 845篇 |
口腔科学 | 163篇 |
临床医学 | 379篇 |
内科学 | 1463篇 |
皮肤病学 | 263篇 |
神经病学 | 582篇 |
特种医学 | 143篇 |
外科学 | 813篇 |
综合类 | 23篇 |
预防医学 | 256篇 |
眼科学 | 131篇 |
药学 | 433篇 |
中国医学 | 19篇 |
肿瘤学 | 621篇 |
出版年
2023年 | 41篇 |
2022年 | 81篇 |
2021年 | 167篇 |
2020年 | 74篇 |
2019年 | 123篇 |
2018年 | 143篇 |
2017年 | 109篇 |
2016年 | 139篇 |
2015年 | 153篇 |
2014年 | 195篇 |
2013年 | 223篇 |
2012年 | 369篇 |
2011年 | 397篇 |
2010年 | 230篇 |
2009年 | 194篇 |
2008年 | 350篇 |
2007年 | 373篇 |
2006年 | 338篇 |
2005年 | 336篇 |
2004年 | 351篇 |
2003年 | 356篇 |
2002年 | 295篇 |
2001年 | 146篇 |
2000年 | 130篇 |
1999年 | 116篇 |
1998年 | 51篇 |
1997年 | 54篇 |
1996年 | 42篇 |
1995年 | 47篇 |
1994年 | 35篇 |
1993年 | 41篇 |
1992年 | 93篇 |
1991年 | 92篇 |
1990年 | 71篇 |
1989年 | 64篇 |
1988年 | 53篇 |
1987年 | 60篇 |
1986年 | 48篇 |
1985年 | 54篇 |
1984年 | 50篇 |
1983年 | 43篇 |
1982年 | 16篇 |
1980年 | 18篇 |
1979年 | 35篇 |
1978年 | 14篇 |
1976年 | 15篇 |
1973年 | 14篇 |
1972年 | 16篇 |
1971年 | 23篇 |
1967年 | 14篇 |
排序方式: 共有6579条查询结果,搜索用时 15 毫秒
71.
72.
Hiroyuki Hisada Yoshiki Sakaguchi Kaori Oshio Satoru Mizutani Hideki Nakagawa Junichi Sato Dai Kubota Miho Obata Rina Cho Sayaka Nagao Yuko Miura Hiroya Mizutani Daisuke Ohki Seiichi Yakabi Yu Takahashi Naomi Kakushima Yosuke Tsuji Nobutake Yamamichi Mitsuhiro Fujishiro 《Current oncology (Toronto, Ont.)》2022,29(7):4678
Although the mortality rates of gastric cancer (GC) are gradually declining, gastric cancer is still the fourth leading cause of cancer-related death worldwide. This may be due to the high rate of patients who are diagnosed with GC at advanced stages. However, in countries such as Japan with endoscopic screening systems, more than half of GCs are discovered at an early stage, enabling endoscopic resection (ER). Especially after the introduction of endoscopic submucosal dissection (ESD) in Japan around 2000, a high en bloc resection rate allowing pathological assessment of margin and depth has become possible. While ER is a diagnostic method of treatment and may not always be curative, it is widely accepted as standard treatment because it is less invasive than surgery and can provide an accurate diagnosis for deciding whether additional surgery is necessary. The curability of ER is currently assessed by the completeness of primary tumor removal and the possibility of lymph node metastasis. This review introduces methods, indications, and curability criteria for ER of EGC. Despite recent advances, several problems remain unsolved. This review will also outline the latest evidence concerning future issues. 相似文献
73.
Shigeru Yamamoto MD Noriko Maeda MD Michiko Tamesa MD Yukiko Nagashima MD Kazuyoshi Suga MD Masaaki Oka MD 《The breast journal》2010,16(1):4-8
Abstract: Ultrasonography (US) is one tool for preoperative diagnosis of lymph node metastases in breast cancer. However, US cannot detect true sentinel lymph nodes (SLNs). We identified SLNs in 60 clinically node‐negative breast cancer patients using a real‐time virtual sonography (RVS) system to display in real time a virtual multi‐planar reconstruction obtained from computed tomography (CT) volume data corresponding to the same cross‐sectional image from US. CT volume data were obtained from our original three‐dimensional CT lymphography (3DCT‐LG), which accurately detects SLNs in breast cancer. SLN metastases were assessed by shape and visibility of the hilum. All patients underwent SLN biopsy and SLN metastases were examined pathologically. In all 60 patients, we were able to detect the same SLNs visualized by 3DCT‐LG. Suspicious SLN metastases were identified in seven of the 60 patients, and four of seven patients were pathologically positive. Positive predictive value was 57%. The remaining 53 patients displayed non‐suspect SLNs in which absence of metastasis from the SLN was confirmed histologically. Overall accuracy was 95%. This is a first attempt at preoperatively identifying SLNs using US guided by the RVS system in breast cancer patients. Although evaluation of SLN metastases was unsatisfactory, this method may be useful for preoperative fine‐needle aspiration cytology for diagnosis of SLN metastases. 相似文献
74.
Hibi K Mizutani M Imazawa M Nakamura T Nonoyama M Shibata H 《Nagoya journal of medical science》2008,70(1-2):35-40
Mucinous cystadenoma of the appendix is a type of appendiceal mucocele and a rather rare condition usually found incidentally in the course of other abdominal surgery. A previous evaluation of 73 appendiceal mucoceles showed that this disease was often associated with adenocarcinoma and other epithelial atypia. This observation suggested that patients with mucinous cystadenoma of the appendix also have some underlying disorders. However, non-epithelial changes associated with appendiceal mucocele have not been reported so far. In this study, we presented for the first time a mucinous cystadenoma of the appendix associated with muscular and neuromatous hyperplasia. 相似文献
75.
Hiroyuki Miyahara Dai Shida Hiroki Matsunaga Yukiko Takahama Sachio Miyamoto 《World journal of gastroenterology : WJG》2013,19(4):604-606
Emphysematous cholecystitis is a rare variant of acute cholecystitis with a high mortality rate.The combination of emphysematous cholecystitis and pneumoperitoneum is also rare.We herein describe a case of emphysematous cholecystitis with massive gas in the abdominal cavity.A 77-year-old male presented with epigastric pain and lassitude lasting for one week.A computed tomography scan demonstrated massive gas in the abdominal cavity.Gas was also detectable inside the gallbladder.Massive ascites as well as a pleural effusion were also detected.Under the diagnosis of perforation of the digestive tract,we performed emergency surgery.Beyond our expectations,the perforation site was not in the alimentary tract,but rather in the gallbladder.We then diagnosed the patient with emphysematous cholecystitis with perforation,and performed cholecystectomy.A pathological examination of the resected gallbladder revealed necrosis in the mucosa and thinning of the wall.Cultures of the ascites detected Clostridium perfringens,a gas-producing microorganism. 相似文献
76.
77.
Yukiko Hasuike Naoto Kakita Makoto Aichi Satoko Masachika Mari Kantou Shoko Ikeda Takahashi Masayoshi Nanami Yasuyuki Nagasawa Takahiro Kuragano Takeshi Nakanishi 《Journal of vascular surgery》2019,69(1):174-180.e2
Objective
For patients with end-stage renal disease on hemodialysis, the durability of vascular access (VA) is still far from optimal, and access survival after intervention for access failure is an important aspect. Procoagulant status is a leading cause of access failure. Coagulation-fibrinolysis imbalance can occur in hemodialyzed patients, but the influence of the imbalance has not been fully elucidated.Methods
We prospectively examined coagulation-fibrinolysis balance to assess the risk of access failure after the intervention of revascularization in a cohort of 462 hemodialysis patients. Thrombin-antithrombin complex (TAT) and plasmin-α2-plasmin inhibitor complex (PIC) are markers for coagulation and fibrinolysis. Median follow-up was 243 days. The end point was clinical access failure: revascularization or access revision. The survival curve for VA patency was assessed using the Kaplan-Meier method and compared using the log-rank test. Cox proportional hazards regression models that allowed adjustment for baseline differences in age, sex, dialysis vintage, diabetes mellitus, and various factors (quantity of blood flow, prothrombin time-international normalized ratio, fibrin degradation products, C-reactive protein, interleukin-6, tumor necrosis factor-α, and pentraxin-3) were used.Results
The 162 patients who reached an end point had smaller access flow volume and smaller percentage of arteriovenous fistula and higher TAT/PIC ratio. Kaplan-Meier analysis indicated that the patients with elevated TAT/PIC ratio showed poorer outcome (P < .001). On Cox regression modeling, elevated TAT/PIC was an independent risk factor for access failure (hazard ratio, 1.58; P = .03).Conclusions
Our results suggest that coagulation-fibrinolysis imbalance is a significant risk factor for access failure and may predict VA failure in hemodialyzed patients after access intervention. 相似文献78.
Katsuhisa Omagari Shun-ichi Morikawa Seiko Nagaoka Yukiko Sadakane Miki Sato Mizuho Hamasaki Shigeko Kato Jun-ichi Masuda Masayuki Osabe Takehiko Kadota Keisuke Sera 《Journal of Clinical Biochemistry and Nutrition》2009,45(1):56-67
Fatty liver is commonly associated with alcohol or metabolic syndrome. We aimed to examine the longitudinal aspects of fatty liver, and clarify the independent predictors for the development or regression of fatty liver. In the present study, the clinical features of 1578 Japanese adults (1208 men and 370 women; 35 to 69 years of age) who visited our center both in 2000 and 2007–2008 were recorded and compared, including liver status diagnosed by ultrasonography. Of the 1578 participants, 217 (13.8%) showed fatty liver development, and 74 (4.7%) showed fatty liver regression. Logistic regression analysis revealed that body mass index and percentage body fat were strongly associated with the development or regression of fatty liver. Metabolic syndrome-related disorders such as serum levels of total cholesterol, triglyceride, uric acid, and fasting blood glucose were also associated with clinical course to some degree. However, the history of alcohol intake, the presence of metabolic syndrome, blood pressure, and habitual physical exercise were not independent predictors for the development or regression of fatty liver. Our present data suggest that control of body weight in men and the percentage body fat in women are particularly important for the prevention or treatment of fatty liver. 相似文献
79.
Extremely early onset of ranitidine action on human histamine H2 receptors expressed in HEK293 cells
Fukushima Y Ishikawa T Saitoh T Tateishi K Ogihara T Fujishiro M Shojima N Honda M Kushiyama A Anai M Sakoda H Ono H Onishi Y Otsuka H Katagiri H Nagai R Omata M Asano T 《Digestion》2003,68(2-3):145-152
BACKGROUND/AIMS: Histamine H2 receptor antagonists are considered to exert their effects on gastric acid secretion more rapidly than proton pump antagonists. However, there are no reports concerning the direct interaction of a histamine H2 receptor antagonist with the human H2 receptor in terms of onset of action. This study aims to characterize how rapidly famotidine and ranitidine, the most widely used histamine H2 receptor antagonists, interact with the human histamine H2 receptor. METHODS: HEK293 cell lines, stably expressing human histamine H2 receptors, were obtained. The dose- and time-dependent effects of famotidine and ranitidine on [3H]-tiotidine binding and histamine-stimulated cAMP production were analyzed. RESULTS: Ranitidine inhibited both [3H]-tiotidine binding and histamine-stimulated cAMP production more promptly than did famotidine. Inhibition of histamine-stimulated cAMP production by Cmax doses of famotidine (20 mg p.o.) and ranitidine (150 mg p.o.) peaked by 15 and 2 min, respectively. [3H]-tiotidine binding was not saturated by 60 min at the famotidine Cmax, while the ranitidine Cmax had produced saturation by 15 min. CONCLUSION: Ranitidine inhibits the human histamine H2 receptor very rapidly. 相似文献
80.
C M Phillips Y Mizutani R M Hochstrasser 《Proceedings of the National Academy of Sciences of the United States of America》1995,92(16):7292-7296
A temperature jump (T-jump) method capable of initiating thermally induced processes on the picosecond time scale in aqueous solutions is introduced. Protein solutions are heated by energy from a laser pulse that is absorbed by homogeneously dispersed molecules of the dye crystal violet. These act as transducers by releasing the energy as heat to cause a T-jump of up to 10 K with a time resolution of 70 ps. The method was applied to the unfolding of RNase A. At pH 5.7 and 59 degrees C, a T-jump of 3-6 K induced unfolding which was detected by picosecond transient infrared spectroscopy of the amide I region between 1600 and 1700 cm-1. The difference spectral profile at 3.5 ns closely resembled that found for the equilibrium (native-unfolded) states. The signal at 1633 cm-1, corresponding to the beta-sheet structure, achieved 15 +/- 2% of the decrease found at equilibrium, within 5.5 ns. However, no decrease in absorbance was detected until 1 ns after the T-ump. The disruption of beta-sheet therefore appears to be subject to a delay of approximately 1 ns. Prior to 1 ns after the T-jump, water might be accessing the intact hydrophobic regions. 相似文献