全文获取类型
收费全文 | 4685篇 |
免费 | 220篇 |
国内免费 | 35篇 |
专业分类
耳鼻咽喉 | 43篇 |
儿科学 | 74篇 |
妇产科学 | 48篇 |
基础医学 | 515篇 |
口腔科学 | 112篇 |
临床医学 | 281篇 |
内科学 | 1326篇 |
皮肤病学 | 56篇 |
神经病学 | 369篇 |
特种医学 | 256篇 |
外科学 | 741篇 |
综合类 | 22篇 |
预防医学 | 157篇 |
眼科学 | 73篇 |
药学 | 346篇 |
中国医学 | 11篇 |
肿瘤学 | 510篇 |
出版年
2023年 | 23篇 |
2022年 | 43篇 |
2021年 | 65篇 |
2020年 | 49篇 |
2019年 | 52篇 |
2018年 | 69篇 |
2017年 | 49篇 |
2016年 | 72篇 |
2015年 | 100篇 |
2014年 | 127篇 |
2013年 | 129篇 |
2012年 | 247篇 |
2011年 | 239篇 |
2010年 | 125篇 |
2009年 | 134篇 |
2008年 | 204篇 |
2007年 | 178篇 |
2006年 | 201篇 |
2005年 | 187篇 |
2004年 | 199篇 |
2003年 | 172篇 |
2002年 | 219篇 |
2001年 | 200篇 |
2000年 | 199篇 |
1999年 | 175篇 |
1998年 | 60篇 |
1997年 | 59篇 |
1996年 | 48篇 |
1995年 | 30篇 |
1994年 | 30篇 |
1993年 | 31篇 |
1992年 | 129篇 |
1991年 | 118篇 |
1990年 | 97篇 |
1989年 | 110篇 |
1988年 | 78篇 |
1987年 | 66篇 |
1986年 | 75篇 |
1985年 | 71篇 |
1984年 | 59篇 |
1983年 | 47篇 |
1982年 | 21篇 |
1979年 | 48篇 |
1978年 | 22篇 |
1977年 | 30篇 |
1976年 | 22篇 |
1974年 | 24篇 |
1971年 | 21篇 |
1969年 | 21篇 |
1967年 | 20篇 |
排序方式: 共有4940条查询结果,搜索用时 15 毫秒
81.
Hormone replacement therapy causes a decrease in hepatocyte growth factor in hypertensive women 总被引:2,自引:0,他引:2
Tamama K Sumino H Ichikawa S Kanda T Kotajima N Fukumura Y Kurabayashi M Murakami M 《Journal of hypertension》2003,21(6):1151-1156
OBJECTIVE: Serum hepatocyte growth factor (HGF) is associated with blood pressure. We investigated whether the serum HGF level differs between hypertensive and normotensive postmenopausal women (PMW) and whether hormone replacement therapy (HRT) alters the serum HGF level and blood pressure in hypertensive and normotensive PMW. DESIGN: Prospective observational study. METHODS: A total of 33 PMW with mild to moderate essential hypertension controlled by antihypertensive treatment (mean age, 57 +/- 6 years) and 23 normotensive PMW (mean age, 57 +/- 7 years) received continuous HRT (0.625 mg of conjugated equine estrogen combined with 2.5 mg of medroxyprogesterone acetate) once a day orally for 12 months, and we measured serum HGF levels and blood pressure before and 12 months after the start of HRT. RESULTS: The baseline serum HGF level was significantly higher in hypertensive PMW than in normotensive PMW. HRT significantly decreased the serum HGF level in hypertensive subjects, from 2.85 +/- 0.64 pmol/l to 2.49 +/- 0.65 pmol/l (P < 0.001), but not in normotensive subjects. HRT did not change blood pressure in either group. CONCLUSIONS: Serum HGF level before the start of HRT was higher in the hypertensive PMW than in the normotensive PMW. Furthermore, HRT decreases serum HGF without decreasing blood pressure in hypertensive PMW. The HRT-induced decrease in serum HGF was greater in hypertensive PMW than in normotensive PMW, and the decrease was independent of blood pressure changes. 相似文献
82.
Tetsuro Okabe Michio Fujisawa Takasi Sekiya Yaeko Ichikawa Jun Goto 《Geriatrics & Gerontology International》2007,7(2):195-197
A case of familial spinocerebellar ataxia 6 with typical symptoms is presented. A 60-year-old Japanese female suffered from gait disturbance, ataxia and dizziness. Head magnetic resonance imaging revealed a typical atrophic image in cerebellum. Genetic tests revealed an expanded allele of 22 CAG repeats at the spinocerebellar ataxia type 6 locus. She was diagnosed with spinocerebellar ataxia 6. Her mother was also diagnosed with the same disease. A mixture of 18 medicinal herbs (modified Zhengan Xifeng Tang) was given according to the differential diagnosis based on the guidelines of traditional Chinese medicine. All of the symptoms were remarkably improved after 60 days of the herbal treatment. One year after discontinuation of the treatment, she complained of gait ataxia. She was treated with the modified Zhengan Xifeng Tang for 60 days. Gait ataxia was markedly improved by the second treatment. Fifteen months after discontinuation of the second treatment, she complained of gait ataxia again. The same remedy was given for 60 days. Gait ataxia was remarkably reduced again. The results may imply therapeutic potential of the medicinal herbs for spinocerebellar ataxia 6. 相似文献
83.
84.
Black (or brown) adrenal cortical adenoma: its characteristic features on computed tomography and endocrine data 总被引:3,自引:0,他引:3
I Komiya N Takasu T Aizawa T Yamada Y Koizumi K Hashizume M Ishihara K Hiramatsu K Ichikawa M Katakura 《The Journal of clinical endocrinology and metabolism》1985,61(4):711-717
Seventeen patients with adrenal adenoma causing Cushing's syndrome, eight patients with Cushing's disease due to hypersecretion of ACTH, and five patients with primary aldosteronism due to an aldosteronoma were studied for their computed tomographic (CT) patterns, hormonal profiles, and macroscopic and microscopic findings of the adrenal gland. Black (or brown) adrenal adenomas were found in 71% of the patients with Cushing's syndrome, but not in patients with aldosteronoma. The adrenal tissue of patients with Cushing's disease was predominantly yellow. The number of compact cells was larger in black or brown adenomas than in yellow tumors or hyperplastic adrenal tissue. In patients with Cushing's syndrome, urinary excretion of 17-ketosteroids (17-KS) and serum aldosterone concentrations were lower in those with black or brown adenomas than in those with yellow adenomas (P less than 0.05). Patients with Cushing's disease had even higher 17-KS and serum aldosterone levels. No difference was found in serum cortisol concentrations and dexamethasone suppressibility in two types of adenomas causing Cushing's syndrome. Visual estimation of radiological density of the adrenal tissue relative to the kidney on CT scan and quantitative measurement of it by CT number revealed a difference between the two types of adrenal tumors causing Cushing's syndrome. Adrenal tumors with decreased density on CT scan were yellow adenomas with predominantly clear cells, and those with equal or increased density were black or brown adenomas with predominantly compact cells. All aldosteronomas had decreased density and consisted of clear cells. It is suggested that black or brown adenomas of the adrenal gland have higher radiological density and accompanying lower serum aldosterone and urinary 17-KS levels than ordinary yellow tumors. The abundance of compact cells may have some significance for the development of this particular type of adrenal tumor. 相似文献
85.
Effect of spironolactone on cardiac sympathetic nerve activity and left ventricular remodeling in patients with dilated cardiomyopathy 总被引:13,自引:0,他引:13
Kasama S Toyama T Kumakura H Takayama Y Ichikawa S Suzuki T Kurabayashi M 《Journal of the American College of Cardiology》2003,41(4):574-581
OBJECTIVES: We sought to evaluate the effects of spironolactone on cardiac sympathetic nerve activity and left ventricular (LV) remodeling in patients with dilated cardiomyopathy (DCM). BACKGROUND: Aldosterone prevents the uptake of norepinephrine and promotes structural remodeling of the heart. Spironolactone, an aldosterone receptor blocker, improves LV remodeling in patients with DCM, but its influence on cardiac sympathetic nerve activity has not been determined. METHODS: We selected 30 patients with DCM who were treated with an angiotensin-converting enzyme inhibitor and a loop diuretic. Fifteen patients were assigned to receive spironolactone additionally, whereas the remaining 15 patients continued their current regimen. The delayed heart/mediastinum (H/M) count ratio, delayed total defect score (TDS), and washout rate (WR) were determined from iodine-123 ((123)I)-meta-iodobenzylguanidine (MIBG) images before and six months after treatment. The left ventricular end-diastolic volume (LVEDV) and left ventricular ejection fraction (LVEF) were determined by echocardiography, and New York Heart Association (NYHA) functional class was estimated.RESULTS: In the spironolactone group, the TDS decreased from 36 +/- 9 to 24 +/- 13 (p < 0.0001), the H/M ratio increased from 1.64 +/- 0.20 to 1.86 +/- 0.27 (p < 0.0001), and WR decreased from 55 +/- 12% to 41 +/- 15% (p < 0.0005). In addition, the LVEDV decreased from 187 +/- 26 to 154 +/- 41 ml (p < 0.005), and LVEF increased from 33 +/- 6% to 39 +/- 6% (p < 0.005). However, there were no significant changes in these parameters in the control group. There was a significant correlation between changes in the (123)I-MIBG findings and changes in LVEDV with spironolactone treatment (TDS: r = 0.684, p = 0.0038; H/M ratio: r = -0.878, p < 0.0001; and WR: r = 0.737, p = 0.0011). The NYHA functional class improved in both groups but showed a greater improvement in the spironolactone group than in the control group (p < 0.01). CONCLUSIONS: Spironolactone improves cardiac sympathetic nerve activity and LV remodeling in patients with DCM. 相似文献
86.
Isolated brain-retrocerebral neurohemal complex of the silkworm of Bombyx mori was stimulated electrically and the released bombyxin (an insulin-like neuropeptide) was measured using time-resolved fluoroimmunoassay. The amount of bombyxin release depended on the number of stimulus pulses delivered to the axonal tract of the bombyxin-producing (BP) neurosecretory cells, and 17 fg of bombyxin per pulse was released from a cell. The titer of bombyxin in the hemolymph of bombyxin-II injected pupae decreased exponentially, the half-life being 170 min. To relate firing activity of a population of BP cells to the hormone titer in the hemolymph, bombyxin titer and its change in the hemolymph were calculated numerically. We assumed that the amount of bombyxin release was proportional to the firing rate of BP cells and the released bombyxin was inactivated with the same time course of injected bombyxin. Our calculations suggested that the hemolymph bombyxin titer may fluctuate dynamically and the mean titer is 380 pg/ml, a level which is close to the actually determined bombyxin titer at middle stages of pupal-adult development. 相似文献
87.
Kohei Ashikaga Haruki Itoh Tomoko Maeda Hidetaka Itoh Yuri Ichikawa Shiori Tanaka Ryuichi Ajisaka Akira Koike Shigeru Makita Kazuto Omiya Yuko Kato Hitoshi Adachi Masatoshi Nagayama Akihiko Tajima Naomi Harada Yoshihiro J Akashi 《Journal of cardiology》2021,77(1):57-64
BackgroundThe current understanding of ventilator efficiency variables during ramp exercise testing in the normal Japanese population is insufficient, and the responses of tidal volume (VT) and minute ventilation (V?E) to the ramp exercise test in the normal Japanese population are not known.MethodsA total of 529 healthy Japanese subjects aged 20–78 years underwent cardiopulmonary exercise testing using a cycle ergometer with ramp protocols. VT and V?E at rest, at anaerobic threshold, and at peak exercise were determined. The slope of V?E versus carbon dioxide (V?CO2) (V?E vs. V?CO2 slope), minimum V?E/V?CO2, and oxygen uptake efficiency slope (OUES) were determined.ResultsFor males and females in their 20 s, peak VT (VTpeak) was 2192 ± 376 and 1509 ± 260 mL (p < 0.001), peak V?E (V?Epeak) was 80.6 ± 18.7 and 57.7 ± 13.9 L/min (sex differences p < 0.001), the V?E vs. V?CO2 slope was 24.4 ± 3.2 and 25.7 ± 3.2 (p = 0.035), the minimum V?E/V?CO2 was 24.2 ± 2.3 and 27.0 ± 2.8 (p < 0.001), and the OUES was 2452 ± 519 and 1991 ± 315 (p < 0.001), respectively. VTpeak and V?Epeak decreased with age and increased with weight and height. The V?E vs. V?CO2 slope and minimum V?E/V?CO2 increased with age, while conversely, the OUES decreased with age.ConclusionsWe have established the normal range of VT and V?E responses, the V?E vs. V?CO2 slope, the minimum V?E/V?CO2, and the OUES for a healthy Japanese population. Some of these parameters were influenced by weight, height, sex, and age. These results provide useful reference values for interpreting the results of cardiopulmonary exercise testing in cardiac patients. 相似文献
88.
89.
Yamazaki M Kimura K Mitamura K Watanabe S Komiyama O Yamamoto K Ichikawa M Hashimoto Y Hagiwara N Maezawa T Imai M Sugaya N 《Kansenshōgaku zasshi. The Journal of the Japanese Association for Infectious Diseases》2000,74(12):1032-1037
The Directigen Flu A + B kit, a rapid diagnostic device for influenza virus A and B was evaluated. The nasopharyngeal aspirates were obtained from 239 patients who visited our hospital, between January and March, 2000, presenting flu-like symptoms. Influenza virus AH1: 77 and AH3: 51 were isolated from 128 specimens and none from 111 specimens. Directigen Flu A + B showed 115 specimens positive and 106 specimens negative. The sensitivity and specificity of this kit were 89.8% (115/128) and 95.5% (106/111) compared with viral isolation. Agreement on positive and negative interpretations between Direction Flu A and this kit was 97.9% (234/239). In the evaluation of this kit for influenza B virus, 60 frozen nasopharyngeal aspirates collected from February to April, 1999 were used. The sensitivity and specificity of this kit were 88.9% (16/18) and 88.1% (37/42) compared with viral isolation. Agreement on positive and negative interpretations between FLU OIA and this kit was 91.7% (55/60). The Directigen A + B demonstrated sensitivity and specificity equivalent to the conventional kits in nasopharingeal aspirates. This kit can also differentiate influenza A and B viruses, a feature which is useful for treatment using anti-viral agents such as amantadine and neuraminidase inhibitor. To date, the kit is the most effective tool for the rapid diagnosis of influenza. 相似文献
90.