全文获取类型
收费全文 | 7024篇 |
免费 | 330篇 |
国内免费 | 33篇 |
专业分类
耳鼻咽喉 | 111篇 |
儿科学 | 120篇 |
妇产科学 | 100篇 |
基础医学 | 939篇 |
口腔科学 | 161篇 |
临床医学 | 393篇 |
内科学 | 1705篇 |
皮肤病学 | 187篇 |
神经病学 | 456篇 |
特种医学 | 171篇 |
外科学 | 1109篇 |
综合类 | 34篇 |
预防医学 | 244篇 |
眼科学 | 137篇 |
药学 | 476篇 |
中国医学 | 21篇 |
肿瘤学 | 1023篇 |
出版年
2023年 | 37篇 |
2022年 | 69篇 |
2021年 | 118篇 |
2020年 | 61篇 |
2019年 | 94篇 |
2018年 | 108篇 |
2017年 | 102篇 |
2016年 | 110篇 |
2015年 | 121篇 |
2014年 | 183篇 |
2013年 | 211篇 |
2012年 | 326篇 |
2011年 | 350篇 |
2010年 | 201篇 |
2009年 | 168篇 |
2008年 | 300篇 |
2007年 | 368篇 |
2006年 | 363篇 |
2005年 | 361篇 |
2004年 | 300篇 |
2003年 | 294篇 |
2002年 | 270篇 |
2001年 | 237篇 |
2000年 | 215篇 |
1999年 | 204篇 |
1998年 | 94篇 |
1997年 | 78篇 |
1996年 | 70篇 |
1995年 | 58篇 |
1994年 | 49篇 |
1993年 | 59篇 |
1992年 | 178篇 |
1991年 | 166篇 |
1990年 | 157篇 |
1989年 | 162篇 |
1988年 | 127篇 |
1987年 | 136篇 |
1986年 | 95篇 |
1985年 | 90篇 |
1984年 | 77篇 |
1983年 | 77篇 |
1982年 | 39篇 |
1981年 | 37篇 |
1980年 | 28篇 |
1979年 | 60篇 |
1978年 | 50篇 |
1977年 | 41篇 |
1975年 | 32篇 |
1973年 | 28篇 |
1970年 | 33篇 |
排序方式: 共有7387条查询结果,搜索用时 656 毫秒
141.
142.
Isamu Ikeda Tadashi Ohno Hideaki Ohno Yoshitsugu Miyazaki Katsutaro Nishimoto Satoshi Fukushima Takamitsu Makino Hiromobu Ihn 《The Journal of dermatology》2014,41(4):340-342
We report a case of refractory Fusarium paronychia in a 42‐year‐old man with Behçet's disease receiving oral cyclosporin and corticosteroid. Symptoms resembling candidal paronychia of his little finger could not be cured by topical ketoconazole and oral terbinafine. The pathogen was identified as Fusarium solani species complex by gene analysis, and was multiple drug resistant. The case eventually resolved by occlusive dressing therapy with 0.5% amorolfine cream for 3 months. 相似文献
143.
144.
145.
Soluble E-selectin, leptin, triglycerides, and insulin resistance in nonobese Japanese type 2 diabetic patients 总被引:2,自引:0,他引:2
Taniguchi A Fukushima M Nakai Y Kuroe A Yamano G Yanagawa T Ohgushi M Ohya M Yoshii S Taki Y Seino Y 《Metabolism: clinical and experimental》2005,54(3):376-380
The aim of the present study was to investigate the relationships between insulin resistance and soluble E-selectin, body mass index (BMI), leptin, and serum lipid profile including triglycerides in nonobese Japanese type 2 diabetic patients. A total of 97 nonobese Japanese type 2 diabetic patients aged 43 to 84 years were examined. The duration of diabetes was 11.2 +/- 0.8 years. In conjunction with BMI and fasting concentrations of plasma glucose, serum lipids (triglycerides, total cholesterol, and high-density lipoprotein cholesterol) and serum insulin, soluble E-selectin, and leptin were also measured. The low-density lipoprotein (LDL) cholesterol level was calculated using the Friedewald formula. Insulin resistance was estimated by the homeostasis model assessment. The subjects were divided into 2 groups according to the value of insulin resistance estimated by the homeostasis model assessment. Values greater than 2.5 were indicative of the insulin-resistant state, and values less than 2.5 were indicative of the insulin-sensitive state. The insulin-resistant group had significantly higher levels of E-selectin, leptin, triglycerides, total and LDL cholesterol, and diastolic blood pressure as compared with the insulin-sensitive group. There was, however, no significant difference in age, sex, diabetes duration, BMI, systolic blood pressure, HbA1c, and high-density lipoprotein cholesterol between the 2 groups. Univariate regression analysis showed that insulin resistance was positively correlated to E-selectin (r = 0.305, P = .003), BMI (r = 0.283, P = .006), leptin (r = 0.296, P = .004), HbA1c (r = 0.241, P = .018), serum triglycerides (r = 0.385, P < .001), serum total (r = 0.240, P = .019) and LDL cholesterol (r = 0.254, P = .013) levels, and systolic (r = 0.247, P = .024) and diastolic (r = 0.305, P = .006) blood pressure. Multiple regression analyses showed that insulin resistance was independently predicted by serum E-selectin (F = 18.4), serum leptin (F = 14.0) and serum triglycerides (F = 20.0) levels, which explained 45.0% of the variability of insulin resistance. From these results, it can be concluded that in conjunction with serum triglycerides and serum leptin, serum E-selectin is another important independent factor associated with insulin resistance in nonobese Japanese type 2 diabetic patients. 相似文献
146.
Delayed improvement of autonomic nervous abnormality after the Maze procedure: time and frequency domain analysis of heart rate variability using 24 hour Holter monitoring
下载免费PDF全文
![点击此处可从《Heart (British Cardiac Society)》网站下载免费的PDF全文](/ch/ext_images/free.gif)
K. Fukushima T. Emori W. Shimizu T. Kurita N. Aihara Y. Kosakai F. Isobe K. Shimomura Y. Kawashima T. Ohe 《Heart (British Cardiac Society)》1997,78(5):499-504
Objective—To analyse heart rate variability in patients with atrial fibrillation after the Maze procedure, to investigate whether the procedure damages the cardiac autonomic fibres supplying the sinus node.
Design and patients—Time and frequency domain analyses of RR variability were performed using 24 hour Holter monitoring one month after surgery in 12 patients with atrial fibrillation who underwent the Maze procedure (Maze group) and in seven patients who underwent cardiac surgery without the Maze procedure (control group). Mean RR intervals (mRR) and the standard deviation of successive RR intervals (SDRR) were determined by time domain analysis, and high frequency (HF), low frequency (LF), and total power (TP) spectral components of RR variability were calculated by frequency domain analysis. Holter monitoring was also performed at six and 12 months after cardiac surgery in the Maze group.
Results—Circadian variation (mean (SD)) in mRR (daytime to night time difference: 119 (60) v 302 (143) ms), SDRR (daytime: 8.4 (3.3) v 37.0 (12.0) ms), TP (daytime: 46.7 (16.0) v 171.8 (30.4) ms), HF (daytime: 19.6 (9.9) v 36.7 (7.1) ms2), and LF/HF (daytime: 0.31 (0.07) v 1.18 (0.46)) was decreased in the Maze group at one month compared with the control group (p < 0.01), but showed improvement at six and 12 months (p < 0.05).
Conclusions—Surgery combined with the Maze procedure markedly suppressed the circadian variation of heart rate over a 24 hour period within one month after surgery, mainly because of damage to the innervation of the sinus node. However, at six and 12 months there was restoration of circadian variation, probably as the result of reinnervation of the sinus node.
Keywords: autonomic nervous system; heart rate variability; Maze procedure 相似文献
Design and patients—Time and frequency domain analyses of RR variability were performed using 24 hour Holter monitoring one month after surgery in 12 patients with atrial fibrillation who underwent the Maze procedure (Maze group) and in seven patients who underwent cardiac surgery without the Maze procedure (control group). Mean RR intervals (mRR) and the standard deviation of successive RR intervals (SDRR) were determined by time domain analysis, and high frequency (HF), low frequency (LF), and total power (TP) spectral components of RR variability were calculated by frequency domain analysis. Holter monitoring was also performed at six and 12 months after cardiac surgery in the Maze group.
Results—Circadian variation (mean (SD)) in mRR (daytime to night time difference: 119 (60) v 302 (143) ms), SDRR (daytime: 8.4 (3.3) v 37.0 (12.0) ms), TP (daytime: 46.7 (16.0) v 171.8 (30.4) ms), HF (daytime: 19.6 (9.9) v 36.7 (7.1) ms2), and LF/HF (daytime: 0.31 (0.07) v 1.18 (0.46)) was decreased in the Maze group at one month compared with the control group (p < 0.01), but showed improvement at six and 12 months (p < 0.05).
Conclusions—Surgery combined with the Maze procedure markedly suppressed the circadian variation of heart rate over a 24 hour period within one month after surgery, mainly because of damage to the innervation of the sinus node. However, at six and 12 months there was restoration of circadian variation, probably as the result of reinnervation of the sinus node.
Keywords: autonomic nervous system; heart rate variability; Maze procedure 相似文献
147.
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
148.
It was reported that neuronal nitric oxide synthase (nNOS) was expressed only in gonadotrophs and folliculo-stellate cells
in the anterior lobe of the pituitary gland. However, recent studies have demonstrated the occurrence of nNOS in the somatotrophs
and lactotrophs. In the present study, we investigated effects of growth hormone-releasing hormone (GHRH), gonadotropin-releasing
hormone (GnRH), and 17β-estradiol on nitric oxide (NO) release in cultured rat anterior pituitary cells in vitro. The NO
2
−
level in the incubation medium of the rat anterior pituitary cells was dependent on the cell density. Pretreatment with 10
μM 17β-estradiol resulted in an increase in medium NO
2
−
level. GHRH and GnRH failed to change medium NO
2
−
levels, but they elicited increases in medium NO
2
−
levels in estrogen-treated cells. The GHRH-induced increase in NO
2
−
level was inhibited by Nχ-nitro-l-arginine methyl ester, a NOS inhibitor. These findings suggest that GnRH and GHRH could activate nNOS in the gonadotrophs
and the somatotrophs, respectively. 相似文献
149.
Yabe D Kuroe A Ohya M Watanabe K Kitatani N Oku M Kurose T Seino Y 《Diabetes research and clinical practice》2008,82(2):e1-e4
Non-specific aggression to endocrine alpha and beta cells as well as exocrine pancreas has been suggested in fulminant type 1 diabetes (FT1DM), while its effect on glucagon secretion and exocrine function is unknown. Here, we report a FT1DM case with exocrine pancreatic insufficiency and enhanced glucagon response to meal ingestion. 相似文献
150.
Kobayashi H Kaern M Araki M Chung K Gardner TS Cantor CR Collins JJ 《Proceedings of the National Academy of Sciences of the United States of America》2004,101(22):8414-8419
Novel cellular behaviors and characteristics can be obtained by coupling engineered gene networks to the cell's natural regulatory circuitry through appropriately designed input and output interfaces. Here, we demonstrate how an engineered genetic circuit can be used to construct cells that respond to biological signals in a predetermined and programmable fashion. We employ a modular design strategy to create Escherichia coli strains where a genetic toggle switch is interfaced with: (i) the SOS signaling pathway responding to DNA damage, and (ii) a transgenic quorum sensing signaling pathway from Vibrio fischeri. The genetic toggle switch endows these strains with binary response dynamics and an epigenetic inheritance that supports a persistent phenotypic alteration in response to transient signals. These features are exploited to engineer cells that form biofilms in response to DNA-damaging agents and cells that activate protein synthesis when the cell population reaches a critical density. Our work represents a step toward the development of "plug-and-play" genetic circuitry that can be used to create cells with programmable behaviors. 相似文献