全文获取类型
收费全文 | 6646篇 |
免费 | 571篇 |
国内免费 | 233篇 |
专业分类
耳鼻咽喉 | 105篇 |
儿科学 | 252篇 |
妇产科学 | 121篇 |
基础医学 | 621篇 |
口腔科学 | 160篇 |
临床医学 | 707篇 |
内科学 | 1162篇 |
皮肤病学 | 138篇 |
神经病学 | 344篇 |
特种医学 | 192篇 |
外科学 | 1053篇 |
综合类 | 771篇 |
一般理论 | 1篇 |
预防医学 | 369篇 |
眼科学 | 247篇 |
药学 | 634篇 |
2篇 | |
中国医学 | 311篇 |
肿瘤学 | 260篇 |
出版年
2024年 | 37篇 |
2023年 | 108篇 |
2022年 | 253篇 |
2021年 | 335篇 |
2020年 | 248篇 |
2019年 | 209篇 |
2018年 | 227篇 |
2017年 | 244篇 |
2016年 | 216篇 |
2015年 | 286篇 |
2014年 | 346篇 |
2013年 | 416篇 |
2012年 | 542篇 |
2011年 | 480篇 |
2010年 | 345篇 |
2009年 | 323篇 |
2008年 | 426篇 |
2007年 | 412篇 |
2006年 | 352篇 |
2005年 | 337篇 |
2004年 | 266篇 |
2003年 | 289篇 |
2002年 | 209篇 |
2001年 | 131篇 |
2000年 | 107篇 |
1999年 | 74篇 |
1998年 | 24篇 |
1997年 | 31篇 |
1996年 | 22篇 |
1995年 | 24篇 |
1994年 | 20篇 |
1993年 | 15篇 |
1992年 | 7篇 |
1991年 | 14篇 |
1990年 | 12篇 |
1989年 | 16篇 |
1988年 | 5篇 |
1987年 | 11篇 |
1986年 | 3篇 |
1985年 | 6篇 |
1984年 | 4篇 |
1983年 | 4篇 |
1982年 | 4篇 |
1974年 | 1篇 |
1971年 | 1篇 |
1968年 | 1篇 |
1966年 | 1篇 |
1965年 | 2篇 |
1957年 | 1篇 |
1943年 | 1篇 |
排序方式: 共有7450条查询结果,搜索用时 15 毫秒
51.
Relationship of ambulatory blood pressure monitoring data to echocardiographic findings in haemodialysis patients 总被引:5,自引:3,他引:2
Erturk S.; Ertug A. E.; Ates K.; Duman N.; Aslan S. M.; Nergisoglu G.; Diker E.; Erol C.; Karatan O.; Erbay B. 《Nephrology, dialysis, transplantation》1996,11(10):2050-2054
BACKGROUND: The present study was performed to assess the value of ambulatoryblood pressure monitoring (ABPM) in determining the adequacyof blood pressure (BP) control, and its relationship to echocardiographicfindings in haemodialysis (HD) patients. METHODS: We studied 40 non-diabetic adult patients who had been on regularHD treatment for a median duration of 43 months. Twenty-four-hourABPM was performed using a non-invasive ABP monitor (Pressurescan,ERKA). Casual BP (cBP) was defined as the average of two measurementsobtained at two HD sessions, one preceding and one followingthe ABP recordings, and was calculated for both the predialysisand postdialysis phases. Two-dimensional and M-mode echocardiographywere performed in each patient to determine interventricularseptal thickness (IVS), left ventricular posterior wall thickness(LVPW), left ventricular fractional shortening (FS), and leftventricular mass index (LVMI) RESULTS: According to average 24-h BP levels, 50% of the patients hadsystolic hypertension (HT) (>139 mmHg), and 72.5% had diastolicHT (>87 mmHg), while only 25% had been diagnosed as HT bycBP measurements (P>0.01 and P>0.0001 respectively). Diurnalvariation in BP was not present in about 80% of the patients.Echocardiography was normal in only four patients (10%). LVMIand LV wall thickness were correlated to ABPM data better thanto cBP measurements. Using stepwise linear regression analysis,LVMI and FVS were positively correlated with systolic BP load(P> 0.0001 and P=0.0001 respectively), and LVPW was positivelycorrelated with night-time systolic BP level (P>0.001). CONCLUSIONS: ABPM is necessary to assess the adequacy of BP control, andis well correlated to end-organ damage of HT in HD patients. 相似文献
52.
3-硝基丙酸预处理诱导沙土鼠脑缺血耐受与海马星形胶质细胞的激活 总被引:2,自引:0,他引:2
目的:探讨海马区星形胶质细胞的激活与3-硝基丙酸(3-NPA)预处理诱导脑缺血耐受的关系。方法:阻断沙土鼠双侧颈总动脉造成前脑缺血模型,通过HE染色和免疫组化观察海马锥体细胞死亡和星形胶质细胞的反应。结果:对照组海马CA1区已失去正常结构,锥体细胞大部分丧失,存活神经元计数显低于假手术组。3-NPA预处理组存活神经元减少,但高于对照组,假手术组海马CA1区仅见少量胶质原纤维酸性蛋白(GFAP)阳性细胞,染色较弱,突起不明显,对照组海马CA1区GFAP阳性细胞增多,多为弱阳性。3-NPA预处理组海马CA1区GFAP阳性细胞数目明显增多,染色较深,突起增粗。结论:星形胶质细胞形态和机能的改变可能与3-硝基丙酸预处理诱导脑缺血耐受有关。 相似文献
53.
Cenk Can Buket Demirci Ay?egül Uysal Yasemin Delen Ak?ay Sezen Ko?ay 《Pharmacological research》2003,48(3):223-230
We examined the effects of the phenothiazine derivative, chlorpromazine on thoracic aortic endothelial cell histology (14 h after LPS challenge) in a model of endotoxic shock in rats. Since excessive formation of tumor necrosis factor-alpha (TNF-alpha) and oxygen-derived free radicals contribute to endothelial injury in endotoxemia, we also evaluated the effect of the drug on the activities of antioxidant enzymes superoxide dismutase (SOD) and catalase in liver tissue in this model and tried to find out whether this possible effect was associated with a change in serum TNF-alpha levels (measured 90 min after chlorpromazine administration). Endotoxemia was induced by a single i.p. injection of lipopolysaccharide (LPS) (5 mg kg(-1) in 1.5 ml of saline; LPS from Escherichia coli serotype 055:B5, L-2880, Sigma Chemical Company). Electron microscopic evaluation of the aortas revealed that chlorpromazine (administered 30 min prior to LPS challenge), in smaller doses (3 mg kg(-1)) ameliorated the endothelial cell injury caused by LPS, whereas it caused deterioration of endothelial cell morphology in higher doses (10 and 25 mg kg(-1)). Chlorpromazine administration caused a significant reduction in serum TNF-alpha levels, which was correlated well with an increase in SOD activity in all drug doses (3, 10 and 25 mg kg(-1)). Catalase activity was increased only in the 25 mg kg(-1) chlorpromazine group. 相似文献
54.
O-羧甲基N-半乳糖化壳聚糖衍生物的设计、合成和表征 总被引:7,自引:0,他引:7
目的:合成和表征O-羧甲基-N-半乳糖化壳聚糖衍生物作为潜在的肝靶向基因载体。方法:以天然聚合物壳聚糖为原料,首先制备得O-羧甲基壳聚糖,然后在其2-NH2上和乳糖酸反应,制得O-羧甲基-N-乳糖酰化壳聚糖;或与乳糖反应,用KB}14还原,制得O-羧甲基-N-乳糖胺化壳聚糖。结果与结论:分别用VF-IR、^1H NMR、^13C NMR和元素分析对其进行了表征。用粉末X-衍射、DSC、TG对其物理性质进行了分析。制得的O-羧甲基-N-乳糖酰化壳聚糖O-羧甲基-N-乳糖胺化壳聚糖有望作为潜在的肝靶向基因载体。 相似文献
55.
56.
Clinical study on therapeutic mechanism of Sini Decoction in treating post-percutaneous transluminal coronary angioplasty ischemia-reperfusion injury in terms of syndrome typing of TCMin treating post-percutaneous transluminal coronary angioplasty ischemia-reperfusion injury in terms of syndrome typing of TCM 下载免费PDF全文
Objective: To study the mechanism of Sini Decoction (SND) in prevention and treatment of post-percutaneous transluminal coronary angioplasty (PTCA) ischemia-reperfusion injury with different Syndrome typing of TCM.Methods: Forty patients who received PTCA were randomly divided equally into the SND group and the control group, there were 10 of Excess Syndrome (ES) and 10 of Deficiency Syndrome (DS)in each group. 25 ml SND was given daily to the SND group from 3 days before operation to the third day after operation. The blood Superoxide dismutase (SOD) activity, malondialdehyde (MDA) and nitric oxide (NO) content of patients were determined before PTCA, and 1 hr, 12 hrs, 24 hrs, 48 hrs and 72 hrs after PTCA.Results: Before PTCA, the cases with DS were characterized by low SOD activity and high MDA content, as compared with the patients with ES, P<0.05. SND could relieve the post-PTCA deprivation of SOD activity and NO content and the elevation of MDA level in both ES and DS patients, the amplitude of elevation of SOD activity in DS patients was higher than that in ES patients (P<0.05).Conclusion: SND has antagonizing effect on post-PTCA ischemia-reperfusion injury, which is more effective in treating patients with DS. 相似文献
57.
验证救心复脉注射液治疗心源性休克的临床疗效。方法:用CA静脉给药治疗心源性休克20例,用多巴胺注射液作对照。结果;CA组有效18例,无效2例,DA组有效9例,无效2例,组间比较,P〉0.05。结论CA和DA均能升高血压,增加心泵功能,改善厥脱证的症脉,但CA比DA升压速度快,幅度高,作用稳定,对心率有双相调节作用,使心动过速患者心率减慢,使心动过缓患者心率增快。 相似文献
58.
Salbutamol or mist in acute bronchiolitis 总被引:1,自引:0,他引:1
Demet Can GÜLten Nan GÜRol Yendur Resmiye Oral Lker GÜNay 《Pediatrics international》1998,40(3):252-255
Abstract Background : The role of bronchodilators in the treatment of bronchiolitis remains controversial.
Methods : A double-blind, placebo controlled trial was performed to evaluate the clinical response to nebulized salbutamol. One hundred and fifty-six infants aged between 7 weeks and 24 months who had had an episode of wheezing and other signs and symptoms of bronchiolitis were randomized to three groups as follows: (i) nebulized salbutamol was administered to 52 patients in group I at a dose of 0.15 mg/kg in 2 mL saline; (ii) saline was nebulized to 52 patients in group II and (iii) in group III 52 patients received mist in a tent. All three groups were administered oxygen during the procedures. Treatment was repeated with the same agent after 30 min if the respiratory score was 5 or more. Respiratory rate, heart rate, oxygen saturation and presence of cyanosis, wheezing, retractions were recorded before and after each treatment.
Results : The decrease in the respiratory score was 5.2 ± 1.8, 0.82 ± 2.4 and 1.7 ± 1.3 in group I, II and III, respectively. The decrease in group I was significantly higher than in the other groups. Heart rate was similar between groups. Oxygen saturation decreased in group I without reaching statistical significance.
Conclusions: Salbutamol was shown to be effective and safe in the treatment of acute bronchiolitis. 相似文献
Methods : A double-blind, placebo controlled trial was performed to evaluate the clinical response to nebulized salbutamol. One hundred and fifty-six infants aged between 7 weeks and 24 months who had had an episode of wheezing and other signs and symptoms of bronchiolitis were randomized to three groups as follows: (i) nebulized salbutamol was administered to 52 patients in group I at a dose of 0.15 mg/kg in 2 mL saline; (ii) saline was nebulized to 52 patients in group II and (iii) in group III 52 patients received mist in a tent. All three groups were administered oxygen during the procedures. Treatment was repeated with the same agent after 30 min if the respiratory score was 5 or more. Respiratory rate, heart rate, oxygen saturation and presence of cyanosis, wheezing, retractions were recorded before and after each treatment.
Results : The decrease in the respiratory score was 5.2 ± 1.8, 0.82 ± 2.4 and 1.7 ± 1.3 in group I, II and III, respectively. The decrease in group I was significantly higher than in the other groups. Heart rate was similar between groups. Oxygen saturation decreased in group I without reaching statistical significance.
Conclusions: Salbutamol was shown to be effective and safe in the treatment of acute bronchiolitis. 相似文献
59.
60.
目的了解大学生社交焦虑和班集体人际关系现状,为高校心理健康保健提供确实的依据。方法对重庆市3所大学共5个班进行交往焦虑量表和大学班级集体人际关系问卷调查。结果农村大学生的社交焦虑高于城镇大学生;男生的负向人缘系数高于女生;非独生子女大学生的负向人缘系数高于独生子女大学生;大学生社交焦虑与负向人缘系数呈显著负相关,大学生的自我认知和自我体验与实际的人际关系并不完全一致。结论大学生社交焦虑与负向人缘系数呈显著负相关。 相似文献