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131.
纤维素酶法提取黄芪多糖 总被引:14,自引:0,他引:14
目的研究纤维素酶处理对黄芪多糖提取效果的影响。方法以提取液的总糖和还原糖为考察指标,确定纤维素酶处理工艺。通过不同提取方法提取多糖及扫描电镜分析,探讨纤维素酶处理的效果。结果纤维素酶处理条件的优化为纤维素酶加入量为60U/g生药,酶处理时间90min,温度50℃。与对照工艺相比得率由24.4%提高至30.3%,增加率为24.2%,而多糖的质量分数基本不变。扫描电镜观察表明,纤维素酶明显地分解了黄芪原料中的部分结构多糖,药渣中的网状结构变得十分清晰。结论纤维素酶处理有助于黄芪多糖的提取,能显著提高黄芪多糖的得率。 相似文献
132.
芦金荣 《中国现代应用药学》2005,22(2):124-126
目的制备一水合羟苯磺酸钙并进行结构鉴定.方法在不加溶剂的情况下,直接用浓硫酸磺化对苯二酚再与CaCO3成盐,在一定条件下脱水制得了产物一水合羟苯磺酸钙,产物结构经IR,^1H-NMR,^13C-NMR,MS,TGA,DSC及粉末X-衍射确证.结果精制品在1.33kPa,80℃下干燥4h,得本品一水合物.TGA,DSC及粉末X-射线衍射表明,本品一水合物与二水合物谱图完全不同.结论简化了反应操作,提高了反应收率,减少了环境污染. 相似文献
133.
目的了解马根维显(Gd-DTPA)动态增强核磁共振(MRI)评估肾积水术后疗效的应用价值。方法单侧肾积水患者11例,年龄7~42岁,平均19.5岁,均为男性;左侧肾积水9例,右侧2例;病因经静脉尿路造影(intravenousurography,IVU)和B超确诊,10例为先天性肾盂输尿管连接部狭窄(pelvicureterjunctionobstruction,PUJO),1例为输尿管中段慢性炎症所致不完全性梗阻;10例PUJO实施狭窄部成形术,另1例施行输尿管狭窄段切除并输尿管端端吻合术。应用Gd-DTPA作为对比剂,分别在术前1个月和术后3个月实施动态增强MRI检查,选取肾实质、肾盂和集合系统的类圆形区域作为兴趣区(regionofinteresting,ROI),计算不同时间点不同兴趣区的信号强度(signalintensity,SI)和相对信号强度(relativeSI,RSI),绘制T-SI曲线,对术前术后肾脏的形态和功能状态进行评估和比较。结果积水肾脏术前肾实质与术后综合评价无显著性差异(P>0.05),肾盂和集合系统排泄对比剂明显减慢,各ROI和SI以及持续时间与术后肾脏相比均有明显的差异(P<0.05)。结论动态增强MRI作为一种简单、安全无创的技术、联合评估肾形态和功能,对于评价肾积水手术疗效具有重要的临床价值。 相似文献
134.
目的:观察异氟醚对缺血再灌注大鼠活体脑片细胞内游离钙的影响,探讨异氟醚脑保护作用的机制。方法:采用线栓法阻闭大鼠大脑中动脉造成局灶性脑缺血,并于缺血2h后拔出栓线给予再灌注。利用细胞内钙离子荧光探针Fluo-3/AM在激光共聚焦显微镜下观察再灌注2h后大鼠脑片细胞内荧光强度。比较异氟醚预处理1h对缺血再灌注大鼠活体脑片额顶叶皮质及纹状体区域Ca2 浓度的影响。结果:缺血再灌注损伤大鼠缺血侧脑片皮层及纹状体Ca2 荧光强度明显升高。脑缺血前给予异氟醚预处理1h可抑制缺血侧大脑皮层细胞内Ca2 含量的增加,对纹状体细胞内Ca2 含量的影响无统计学差异。结论:缺血前给予异氟醚预处理可有效减轻额顶叶皮层细胞内的钙超载,对纹状体区域脑细胞内游离钙水平影响较小,提示异氟醚的脑保护作用在不同脑区存在差异。 相似文献
135.
David B Preen Belinda E S Bailey Alan Wright Peter Kendall Martin Phillips Joseph Hung Randall Hendriks Annette Mather Elizabeth Williams 《International journal for quality in health care》2005,17(1):43-51
OBJECTIVE: To determine the impact of a hospital-coordinated discharge care plan, involving a multidisciplinary team of primary health care providers, on hospital length of stay, quality of life, and both patient and general practitioner inclusion in, and satisfaction with, discharge procedures. DESIGN: This investigation comprised a prospective, randomized, controlled, clinical trial. SETTING: This multicentre and cross-jurisdictional study focused on areas of tertiary and primary health care as well as community allied health in Western Australia. PARTICIPANTS: Patients (n = 189) with chronic cardiorespiratory diagnoses were recruited from respiratory, cardiovascular, and general medical wards at two tertiary hospitals. INTERVENTION: Subjects were randomly assigned to one of two groups. Intervention group patients received a discharge care plan in accordance with that outlined in the Australian Enhanced Primary Care Package, completed before discharge and sent to the patient's general practitioner and other community service providers for review. Control patients were discharged under existing hospital processes. Outcome measures. Patients and general practitioners were surveyed pre-discharge and 7 days post-discharge for quality of life and opinion of discharge procedures. Hospital length of stay was also determined. RESULTS: Significant improvements in discharge planning involvement, health service access, confidence with discharge procedures, and opinion of discharge based on previous experience were seen for patients who received the discharge care plan. Further, improved perceptions of mental quality of life were observed within the first week post-discharge for intervention patients. Length of stay showed no difference between groups. Extent and speed of hospital-general practitioner communication were significantly improved via the intervention. CONCLUSIONS: Our results indicate that a multidisciplinary discharge care plan, initiated before separation, improves quality of life, involvement, and satisfaction with discharge care, and hospital-general practitioner integration. As such, it possesses benefits over current Western Australian hospital discharge procedures for the care of chronically ill populations. 相似文献
136.
Bogaert J Kuzo R Dymarkowski S Janssen L Celis I Budts W Gewillig M 《European radiology》2000,10(12):1847-1854
Regular follow-up is required in patients with previous intervention for coarctation of the aorta to detect recoarctation
or aneurysm formation. In this study we describe the findings encountered on routine follow-up exams and we compare the use
of contrast-enhanced 3D MR angiography (CE MRA) with fast spin-echo MRI (FSE) to study the thoracic aorta after previous intervention.
In 51 consecutive patients previously treated for aortic coarctation, 74 MR studies of the thoracic aorta were performed during
a 2-year period using CE MRA and FSE MRI. The thoracic aorta was evaluated for abnormalities of course, caliber, shape, and
pathology of side branches. The CE MRA and FSE MRI studies were evaluated side by side by consensus of two reviewers evaluating
which MR technique depicted the abnormalities of the thoracic aorta the best. Of 74 exams, six clinically important abnormalities
were found: four aneurysms and two restenoses. Two small pseudoaneurysms were missed on the FSE studies. Contrast-enhanced
MRA was judged to visualize aortic abnormalities better than FSE (47 of 74 MR studies) especially for the transverse aortic
arch, coarctation site, left subclavian artery, and aortic arch configuration. For the ascending aorta and distal descending
aorta, CE MRA and FSE performed equally well. Aortic diameters measured at four levels in the first 18 MRI studies showed
no significant differences in diameter when measured by FSE or CE MRA (p = not significant). Clinically important abnormalities, such as aneurysm formation and restenosis, can be present years after
treatment for aortic coarctation. In the regular follow-up of these patients, CE MRA may provide additional diagnostic information
compared with FSE and should be included as part of the routine exam.
Received: 3 April 2000; Revised: 5 July 2000; Accepted: 7 July 2000 相似文献
137.
Wolfs JF van den Ham LF ter Laak MP van der Zwan A Tulleken CA 《Acta neurochirurgica》2000,142(12):1399-1407
Summary Background. The nonocclusive Excimer laser-assisted bypass technique has been described in previous studies and proved to be a promising
bypass operation in vascular brain surgery. Little is known about the morphological regeneration process of the laser-assisted
anastomosis in time.
By way of a scanning electron microscopic study we examined the way in which the anastomosis site created by the nonocclusive
Excimer laser-assisted anastomosis technique becomes endothelialized.
Methods. In 14 rabbits the internal jugular vein was placed in a loop on the abdominal aorta. The distal anastomosis was made using
the nonocclusive Excimer laser-assisted technique. The proximal anastomosis was made either laser-assisted or conventional
end-to-side. After clipping of the aorta between the two anastomoses sites the vein served as a bypass. To evaluate the endothelialization
at the laser-assisted anastomosis site in time, a scanning electron microscopic study was performed.
Results. In the first hours after the bypass operation a new intimal surface is formed by fibrin and activated platelets. Some leukocytes
are seen during the first days. The endothelialization process of the laser-assisted anastomosis site begins one day after
the operation. The gradual endothelialization process evolved along two lines. First, endothelial cells grow from the side
of the aorta to the bypass. Second, after one day solitary (blood-borne) endothelial cells deposit on the laser edge and the
sutures, covering the platelet aggregates.
Conclusions. The endothelialization of the Excimer laser-assisted anastomosis is more or less completed 9 days after the operation. The
edge created by the laser becomes smoother after a few days and is gone for the most part after 9 days. 相似文献
138.
氩激光对培养的牛视网膜色素上皮细胞损伤的扫描电镜观察 总被引:2,自引:1,他引:2
目的采用扫描电镜观察氩激光对体外培养的牛视网膜色素上皮(RPE)细胞表面的损伤情况。方法培养牛视网膜色素上皮细胞,将第4代细胞传代成融合状态后,用氩激光对RPE细胞进行照射,激光能量为0.8W,曝光时间为0.2s,光斑直径为200μm,激光照射后用扫描电镜观察色素上皮细胞表面超微结构变化。结果激光照射后,可见光斑中央区的细胞脱失,光斑周边损伤细胞主要表现为表面微绒毛的减少或消失,微绒毛卷曲,有些细胞边缘卷曲及细胞膜破裂出现不规则小孔。结论激光对体外培养的RPE细胞照射可造成色素上皮细胞脱失,细胞膜损伤及微绒毛损伤。 相似文献
139.
玉米赤霉烯酮对细胞间隙连接通讯的影响 总被引:5,自引:0,他引:5
目的 了解真菌性雌激素玉米赤霉烯酮(ZEA)对细胞间隙连接通讯(GJIC)的影响。方法 用荧光漂白后恢复(fluorescence redistribution after photobleaching,FRAP)技术,在激光扫描共聚焦显微镜下观察ZEA对HaCaT细胞GJIC功能的影响。结果 ZEA在0.1μmol/L对HaCaT细胞的GJIC没有明显影响,但在I—100μmol/L浓度下都有明显的抑制作用。ZEA不能有效地拮抗TPA引起的GJIC抑制。结论 ZEA在1μmol/L以上就能抑制GJIC功能,提示它在一定条件下可能有促癌作用。 相似文献
140.
The in vitro culture,maturation and cryopr-eservation of oocytes are all the i mportant parts inthe assisted reproductive technology.Mature oo-cyte(i.e.MⅡoocytes)is arrested at the meta-phase stage of meiosisⅡ,in which chromosomesare attached to the spindle microtubles and line uponthe equatorial plateinthe normal spindles.Dis-organized structure of spindles can not onlylead tosuch morphologic changes as unwound chromo-somes but also the chromosome nondisjuction andresultant aneuploid.When t… 相似文献