全文获取类型
收费全文 | 379篇 |
免费 | 23篇 |
国内免费 | 31篇 |
专业分类
儿科学 | 29篇 |
妇产科学 | 9篇 |
基础医学 | 47篇 |
口腔科学 | 8篇 |
临床医学 | 62篇 |
内科学 | 74篇 |
皮肤病学 | 9篇 |
神经病学 | 7篇 |
特种医学 | 78篇 |
外科学 | 15篇 |
综合类 | 14篇 |
预防医学 | 12篇 |
眼科学 | 23篇 |
药学 | 23篇 |
1篇 | |
肿瘤学 | 22篇 |
出版年
2024年 | 1篇 |
2023年 | 2篇 |
2021年 | 2篇 |
2020年 | 1篇 |
2019年 | 2篇 |
2018年 | 6篇 |
2017年 | 4篇 |
2016年 | 5篇 |
2015年 | 16篇 |
2014年 | 8篇 |
2013年 | 16篇 |
2012年 | 11篇 |
2011年 | 14篇 |
2010年 | 23篇 |
2009年 | 11篇 |
2008年 | 10篇 |
2007年 | 33篇 |
2006年 | 12篇 |
2005年 | 14篇 |
2004年 | 12篇 |
2003年 | 7篇 |
2002年 | 10篇 |
2001年 | 8篇 |
2000年 | 9篇 |
1999年 | 1篇 |
1998年 | 23篇 |
1997年 | 15篇 |
1996年 | 17篇 |
1995年 | 14篇 |
1994年 | 19篇 |
1993年 | 15篇 |
1992年 | 3篇 |
1991年 | 6篇 |
1990年 | 1篇 |
1989年 | 9篇 |
1988年 | 18篇 |
1987年 | 12篇 |
1986年 | 12篇 |
1985年 | 6篇 |
1984年 | 5篇 |
1983年 | 7篇 |
1982年 | 3篇 |
1981年 | 2篇 |
1980年 | 2篇 |
1977年 | 1篇 |
1976年 | 2篇 |
1975年 | 3篇 |
排序方式: 共有433条查询结果,搜索用时 0 毫秒
31.
CHAN CHS; CHAN RCY; ARNOLD M; CHEUNG H; CHEUNG SW; CHENG AFB 《QJM : monthly journal of the Association of Physicians》1992,82(1):15-23
A prospective study of the efficacy of bronchoscopy and tuberculostearicacid assay in the diagnosis of sputum smear-negative pulmonarytuberculosis (TB) was carried out in 39 patients with symptomsand radiographic changes suggestive of active pulmonary TB.The diagnosis of TB was confirmed in 15 patients, probable TBwas diagnosed in eight and 16 patients did not have TB. An earlydiagnosis of TB was made by bronchoscopy in six patients (40per cent). Culture of sputum obtained before bronchoscopy waspositive in nine patients (60 per cent) while combined withbronchoscopy specimens, a positive mycobacterial culture wasobtained in 12 patients (80 per cent). Mycobacteria were culturedfrom transbronchial biopsy specimens from five patients (33per cent) but none of these was exclusively positive. Histologicalexamination of transbronchial biopsy tissue was diagnostic ofTB in four patients and it was the exclusive means of earlydiagnosis in two. Transbronchial biopsy also provided an alternativediagnosis in four other patients. Tuberculostearic acid assayhad a sensitivity of 0.40 in bronchial aspirate, 0.80 in bronchoalveolarlavage fluid, and 0.27 in transbronchial biopsy specimens: thecombined result was 0.87. In nine patients with pulmonary TBin whom an early diagnosis could not be made, the tuberculostearicacid assay was positive in seven (78 per cent). We concludethat bronchoscopy with bronchoalveolar lavage and transbronchialbiopsy is helpful in providing early diagnosis and positiveculture results. Assay of tuberculostearic acid in bronchoalveolarlavage fluid is a useful adjunct to early diagnosis. However,mycobacterial culture and assay of tuberculostearic acid intransbronchial biopsy specimens have little diagnostic value. 相似文献
32.
心肌梗死大鼠心肌细胞凋亡及磷酸肌酸的干预 总被引:3,自引:0,他引:3
目的:缺血引起的心肌能量供应不足是心肌细胞凋亡主要的因素之一,观察补充外源性能量磷酸肌酸对缺血心肌细胞凋亡和心功能的影响。方法:实验于2003-04/06在解放军总医院老年心血管病研究所实验室完成。选用SD大鼠50只,按随机数字表法分为3组:①磷酸肌酸组19只,结扎左冠状动脉制作心肌梗死模型,结扎前30min按200mg/kg的剂量腹腔注射磷酸肌酸1次。②缺血对照组21只,心肌缺血方法同磷酸肌酸组,结扎前30min腹腔注射相同体积的50g/L葡萄糖注射液1次。③正常对照组10只,仅在冠状动脉下穿线,不结扎冠状动脉,其余同缺血对照组。结扎冠状动脉6h后,取各组大鼠心脏标本做石蜡切片,缺口末端标记法染色,高倍镜下计数心肌细胞凋亡指数,凋亡指数=凋亡心肌细胞数/心肌细胞总数;取心脏标本前,测左心室收缩压、舒张末压和压力变化速度,并进行组间比较。结果:磷酸肌酸组大鼠造模时死亡9只;缺血对照组造模时死亡10只,造模成功后6h内死亡1只,进入结果分析共30只大鼠,每组10只。①缺血对照组大鼠的左心室舒张末压显著高于正常对照组[(13.9±5.3vs.2.8±3.2)mmHg(P<0.01)],左心室压力变化速度显著低于正常对照组[(705.8±111.7vs.1141.7±94.5)mmHg/s(P<0.01)];磷酸肌酸组大鼠的左心室舒张末压显著低于缺血对照组[(8.9±3.5)mmHg(P<0.05)];左心室压力变化速度显著高于缺血对照组[(841.5±76.1)mmHg/s(P<0.01)];左心室收缩压与缺血对照组差异无显著性意义(P>0.05)。②磷酸肌酸组大鼠的心肌细胞凋亡指数显著低于缺血对照组(0.203±0.054vs.0.278±0.052,P=0.006)。结论:补充外源性能量磷酸肌酸可以减少缺血后心肌细胞凋亡,并改善心功能,磷酸肌酸抑制缺血心肌细胞凋亡可能是改善心肌梗死后心功能的主要作用途径之一。 相似文献
33.
I. V. Pinchuk R. C. Mifflin J. I. Saada D. W. Powell 《Current gastroenterology reports》2010,12(5):310-318
The non–white blood cell mesenchymal elements of the intestinal lamina propria are the myofibroblasts, fibroblasts, pericytes,
stromal stem cells, muscularis mucosae, and the smooth muscle of the villus core associated with the lymphatic lacteal. We
review the functional anatomy of these mesenchymal cells, what is known about their origin in the embryo and their replacement
in adults, their putative role in intestinal mucosal morphogenesis, and the intestinal stem cell niche, and we consider new
information about myofibroblasts as nonprofessional immune cells. Although our knowledge of the function of mesenchymal cells
in intestinal disease is rudimentary, we briefly consider here their roles in cancer and intestinal inflammation. 相似文献
34.
OBJECTIVE: This was a double-blind, randomized multicentre trial comparing efficacy and safety of brivudin (125 mg, once a day) and famciclovir (250 mg, three times a day), both given orally for 7 days, in the treatment of herpes zoster. METHODS: A total of 2027 immunocompetent zoster patients>or=50 years with zoster-related pain at presentation were included. Outcome measures embraced prevalence of postherpetic neuralgia (PHN), defined as at least moderate pain 3 months after treatment initiation, duration of PHN, prevalence and duration of zoster-associated pain (ZAP), duration of vesicle formation and rash healing. RESULTS: The prevalence of PHN at month 3 was 11.3% with brivudin and 9.6% with famciclovir [per-protocol (PP) population]. Equivalence of the two drugs could be demonstrated (P=0.01, PP and intention-to-treat analysis). The median duration of PHN was 46.5 days with brivudin and 58 days with famciclovir (P=0.54, PP analysis). Prevalence and duration of ZAP did not differ significantly between treatment groups. The prevalence of PHN was higher in patients>or=65 years (brivudin: 16.4%, famciclovir: 16.4%), and in patients with severe rash (brivudin: 13.4%, famciclovir: 15.7%), without significant differences between treatment groups. In patients>or=65 years, median duration of PHN was shorter with brivudin than with famciclovir (39.5 vs. 57.5 days), although the difference was not statistically significant. The two drugs had equivalent efficacy in being able to accelerate the stop of vesicle formation, and lesion healing. Adverse events were similar in nature and prevalence among groups. CONCLUSIONS: The study demonstrated equivalent efficacy of brivudin and famciclovir in the treatment of herpes zoster regarding the prevention of chronic pain and the resolution of signs and symptoms of acute herpes zoster. Compared with famciclovir, brivudin provides equivalent efficacy and safety at a more convenient once-daily dose schedule. 相似文献
35.
36.
37.
Peripheral vascular disease is a serious and frequent problem in diabetic patients. Since the beginning of the widespread use of erythropoietin (EPO), we have noted an increase in peripheral vascular disease in diabetic patients receiving peritoneal dialysis and erythropoietin. This prompted us to study the effects of erythropoietin on peripheral vascular disease in patients receiving peritoneal dialysis. We retrospectively reviewed medical records of all diabetic patients in our program who received peritoneal dialysis from 1990 to 1996. Demographic and laboratory data as well as EPO use data were collected. Hospital days and occurrence of vascular events (defined as peripheral vascular surgery, amputation, or recommendation of vascular surgery or amputation by a vascular surgeon) were determined for diabetic patients receiving peritoneal dialysis. Comparisons were made between those who received EPO and those who did not received EPO, as well as comparing vascular events in 28 patients who received peritoneal dialysis before and after beginning EPO. Patients who received erythropoietin were found to have a significantly shorter time to a first vascular event, a greater number of vascular events, and more hospital days associated with vascular disease than diabetic patients who did not receive erythropoietin. With multivariate analysis, significant risk factors for the development of peripheral vascular disease in these patients were erythropoietin use, erythropoietin dose, and smoking. Twenty-eight patients who initially performed peritoneal dialysis without receiving EPO, and later received EPO, had a significant increase in vascular events, including amputations only while receiving EPO. We found the use of erythropoietin to be associated with peripheral vascular events in diabetic patients who receive peritoneal dialysis. Further investigation is warranted. 相似文献
38.
A randomized prospective comparison of oral versus intraperitoneal ofloxacin as the primary treatment of CAPD peritonitis 总被引:1,自引:0,他引:1
Ignatius KP CHENG SL LUI GX FANG PY CHAU SW CHENG Frances H CHIU TM CHAN WK LO BY CHOY CY LO 《Nephrology (Carlton, Vic.)》1997,3(6):431-435
Summary: Oral ofloxacin has been successfully used in our centres for the primary treatment of peritonitis complicating continous ambulatory peritoneal dialysis (CAPD). In view of the progressive rise in the resistance rate to ofloxacin among peritoneal bacterial isolates, a study was conducted to determine if oral ofloxacin remains a viable first line treatment for CAPD peritonitis in our centres and if the result can be improved by changing from an oral to an intraperitoneal (i.p.) route. In patients on three 2 L daily CAPD exchanges, ofloxacin given at the i.p. dosage of 200 mg loading followed by 25 mg/L of peritoneal dialysate achieved overnight trough peritoneal levels which are at least four times the minimal 90% inhibitory concentration (MIC90) of most bacterial pathogens without significant accumulation in the systemic circulation. This i.p. dosage was therefore chosen for the clinical study and the result was compared to that using ofloxacin given in the oral dosage of 400 mg loading followed by 300 mg once daily as maintenance. of all the recruited episodes, 35 were eligible for analysis. the overall primary cure rate including primary failures and relapses was 55.6% (10/18) in the oral treatment group and 70.6% (12/17) in the i.p. treatment group. the corresponding figures for gram positive bacterial (g +) infections were 36.4% and 50%, for gram negative bacterial (g -) infections were 66.7 and 80% and for culture negative infections were 75 and 80%. In culture positive cases, all treatment failures were due to resistant infections which were observed in 42.3% of all bacterial isolates, 47.1% of g + isolates and 33.3% of g - isolates. Due to the high background level of bacterial resistance among our CAPD population, ofloxacin monotherapy given either by the oral or the i.p. route can no longer be recommended for the primary treatment of CAPD peritonitis. 相似文献
39.
Tina Hines RN PhD Steven W. Mifflin PhD 《American journal of obstetrics and gynecology》1997,177(6):1502-1508
OBJECTIVES: Our purpose was to determine the contribution of centrally released nitric oxide to baseline sympathetic tone and reflex cardiovascular responses to cardiac stretch in the pregnant rat. STUDY DESIGN: Baseline blood pressure and renal sympathetic nerve activity and reflex changes in these variables in response to intraatrial saline solution injections were measured in anesthetized pregnant (n = 24) and virgin (n = 27) rats before and after bilateral microinjection of L-nitroarginine methyl ester (0.01 to 1 μmol) into the dorsal medulla. Data were analyzed with use of nonparametric analysis of variance. RESULTS: L-Nitroarginine methyl ester microinjection altered basal blood pressure and sympathetic nerve activity (p < 0.05) in virgin but not pregnant rats. L-Nitroarginine methyl ester significantly and equivalently attenuated the reflex sympathoinhibitory and depressor responses to cardiac stretch for 40 minutes in pregnant and virgin animals. CONCLUSION: Central nitric oxide does not modulate basal sympathetic tone in the pregnant rat but is released in the medulla in response to cardiac stretch and plays a role in reflex cardiovascular responses similar to that in virgin rats.(Am J Obstet Gynecol 1997;177:1502-8.) 相似文献
40.