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51.
Studies have shown that both food deprivation and response cost have important influences on the magnitude of self-administration of a wide variety of psychoactive drugs. In an attempt to extend these findings to the smoked route of drug self-administration, the effects of food allotment and fixed-ratio (FR) value were evaluated in four male rhesus monkeys trained to smoke cocaine base. In the first phase of the experiment, monkeys were trained to self-administer smoked cocaine base under a chained progressive-ratio (PR), fixed-ratio (FR) schedule during daily experimental sessions. Monkeys were required to make 20 lever-press responses and then five inhalations on a smoking spout to obtain the first smoke delivery. The lever ratio then increased to 60, 140, 300, 620, 1260, 2540, and 4940 for each successive smoke delivery. The initial lever ratio value was reset to 20 at the beginning of each daily session. The body weights of three monkeys were determined under free-feeding conditions. Monkeys were then restricted to 100 g food and, when body weights had stabilized, the daily food allotment was increased to 150 g, approximately 210 g, or greater than 400 g (satiation). As the daily food allotment and body weight increased, the mean number of smoke deliveries decreased in two of three monkeys. In the second phase of the experiment, three monkeys were maintained under either food-satiated or food-restricted conditions. Body weights were maintained at approximately 90% of their free-feeding weights under food-restricted conditions. The cost of the drug (lever FR value) was constant within each experimental session, but was increased after 3 consecutive days of stable responding. Fixed-ratio values were increased from 128 to 256, 512, 1024, and 2048. Monkeys were required to complete the lever FR value and then to make five inhalations on the smoking spout to gain access to 1.0 mg/kg per delivery cocaine base. The mean number of smoke deliveries increased at FR 256, 512, and 1024 when monkeys were food-restricted as opposed to food-satiated. Correspondingly, the mean number of responses increased under food-restricted conditions. Responding continued to increase over a wider range of FR values, and the peak number of responses was higher under food-restricted, as opposed to food-satiated conditions. These results, using the smoking route of administration, are consistent with the hypothesis that food deprivation increases the self-administration of reinforcing drugs.  相似文献   
52.
目的 探讨门脉高压症出血病人肝功能变化情况 ,同时评价应用乌司他丁 (Ulinastatin ,UTI)治疗的效果。方法 将 4 6例肝硬化门脉高压症出血病人分为两组 :Ⅰ组 (n =2 2 )为一般治疗组 ,Ⅱ组 (n =2 4 )为UTI治疗组 ,分别检测Ⅰ、Ⅱ组出血后 1,2 ,4 ,7,10 ,14d血ET变化情况 ,并检测1,7,14d的肝功能。另选肝硬化门脉高压症未出血病人 (n =2 0 ) ,检测血浆ET ,作为对照组。结果 出血后 7,14d ,Ⅰ、Ⅱ组总胆红素 (TBIL)均呈先升高后下降 ,但Ⅱ组较Ⅰ组下降快 (分别P <0 0 5 ,P <0 0 1)。ALT、AST亦呈先升高后下降 ,但于出血后 14日Ⅱ组较Ⅰ组下降快 (P <0 0 5 )。Ⅰ、Ⅱ组出血后 1d血ET浓度较对照组显著升高 (P <0 0 1) ,随后逐步下降。Ⅱ组ET下降较Ⅰ组快 ,于出血后 2d(P <0 0 5 )、4d (P <0 0 1)、7d(P <0 0 5 )有显著差异。出血后 1dⅠ、Ⅱ组ET浓度与TBIL呈正相关 (r=0 734,P <0 0 1) ;Ⅰ、Ⅱ组血ET下降指数与TBIL增高指数呈负相关 (r =- 0 4 86 ,P <0 0 5 )。结论 肝硬化门脉高压症大出血后应用UTI治疗可抑制TBIL、ALT、AST、ET等的升高 ,起到保护肝脏功能的作用。  相似文献   
53.
美宝湿润烧伤膏在治疗慢性泪囊炎的应用   总被引:16,自引:8,他引:8  
目的:观察美宝湿润烧伤膏(MEBO)在治疗慢性泪囊炎的应用价值。方法:对87例102只慢性泪囊炎采用泪道探通手术与MEBO置留治疗。常规泪点表面麻醉,扩张泪点,用生理盐水或氯霉素眼水冲洗鼻泪管、泪囊、泪小管,再用无菌注射器装入5ml MEBO,用5号自制泪道冲洗针沿泪道方向插入,直达泪囊推药,使鼻泪管、泪囊、泪小管内充满MEBO,一周后继续上述方法治疗,一般连续治疗2—5次。结果:治疗总有效率为100%,随访6个月,无一例复发。结论:在泪道探通手术后随即留置MEBO治疗慢性泪囊炎,临床效果良好,操作简单方便,经济有效,值得临床推广应用。  相似文献   
54.
醒脑静注射液治疗肺性脑病31例疗效分析   总被引:5,自引:0,他引:5  
目的 :探讨醒脑静注射液治疗肺性脑病的临床疗效。方法 :采用随机分组对照法 ,将 6 1例肺性脑病患者分为加用醒脑静组 (治疗组 ) 31例和单纯西药治疗组 (对照组 ) 30例 ,进行疗效对比分析。结果 :治疗组治愈12例 ,有效 15例 ,总有效率 87.10 % ;对照组治愈 5例 ,有效 16例 ,总有效率 70 .0 % ,2组疗效差异有显著性(P<0 .0 5 )。从时效关系看 :治疗组对意识障碍的起效时间〔(72 .0 0± 33.94 )小时〕明显快于对照组〔(117.71± 34.70 )小时 ,P<0 .0 1〕,表现为促醒时间短 ,意识恢复正常快 ,并能达到镇静安神的作用 ;从改善原发病症状、体征及血气指标看 :治疗组在改善头痛、失眠、多语、幻觉、谵妄、狂躁及喘憋等症状方面明显优于对照组 (P<0 .0 5 ) ,对降低 Pa CO2 效果亦明显优于对照组 (P<0 .0 1)。结论 :醒脑静注射液具有开窍醒脑、行痰通瘀、镇静止痉和清热解毒等功效 ,是防治肺性脑病的安全、有效药物。  相似文献   
55.
目的:探讨非体外循环心脏不停跳冠状动脉搭桥术的安全性和早期临床效果。方法:自2000年7月至2002年3月51例冠心病患接受冠状动脉搭桥手术,按手术方式分为非体外循环组(n=21)和传统体外循环组(n=30)。将两组病人的术前临床资料,手术方式,术后并发症和疗效等进行对比分析。结果:两组术前临床资料无明显差异。非体外循环组手术时间,术后出血输血量,呼吸机辅助时间显少于体外循环组,并且术后心律失常的发生率明显降低(P均<0.05),其他重要器官的并发症发生率亦低于体外循环组。两组平均随访9.6个月,心绞痛均消失,心功能改善,活动量明显增加。结论:非体外循环冠状动脉搭桥术是安全可行的,并发症少,近期疗效满意。  相似文献   
56.
山东省中小学生麻疹爆发原因的病例对照研究   总被引:12,自引:5,他引:7  
为探讨山东省中小学生麻疹爆发的原因 ,采用 1∶2配比的病例对照方法对中小学生麻疹疫苗 (MV)效力进行了研究 ,同时对近年来中小学生MV接种率进行了估算。结果显示 :中小学生MV效力为 74 % ,95 %可信区间为4 7%~ 88% ;小学生MV效力明显高于中学生 ,分别为 82 %和 6 8% ;1999~ 2 0 0 1年学龄儿童的估算接种率分别为75 4 %、75 6 %和 5 5 7%。较低的MV效力和接种率是计划免疫工作薄弱地区中小学生麻疹爆发的主要原因。  相似文献   
57.
This correlational and comparative study explored whether self-reports of self-efficacy and dyspnea perceptions predict the perceived level of functional performance in adults who have chronic obstructive pulmonary disease (COPD). The convenience sample included 97 Caucasian men (52) and women (45). Participants had to have a forced expiratory volume in 1 second (FEV1) of less than 70% predicted, and a FEV1/forced vital capacity (FVC) of less than 70%. Participants were recruited from pulmonary function laboratories and from better breather support groups in a Midwestern state. Three standardized, self-report instruments, COPD Self-Efficacy Scale (CSES), the Pulmonary Functional Status and Dyspnea Questionnaire (PFSDQ), and Functional Performance Inventory (FPI) were used to measure the participants' self-report of their perceptions of self-efficacy, dyspnea, and functional performance. Dyspnea predicted 38.1% of the variance in functional performance, with self-efficacy contributing an additional 6.5% to the variance in the total sample. Self-efficacy predicted 36.5% of the variance in functional performance in men, with dyspnea contributing an additional 7.2% to the variance. However, in women, only dyspnea was a significant predictor of functional performance, at 48.5% when both dyspnea and self-efficacy were entered as independent variables. To improve patients' perceptions of functional performance, nurses can use methods such as breathing techniques and upper- and lower-body exercises that increase optimal management of dyspnea. Nurses may increase the self-efficacy of managing dyspnea by helping patients master breathing techniques and exercise through coaching and providing vicarious experiences through patient support groups or pulmonary rehabilitation programs.  相似文献   
58.
Patients on cyclosporin A (CsA) often develop hyperuricaemiaand gout. In transplant patients the use of uricosuric drugsfor treating hyperuricaemia may be preferable to allopurinolbecause of the known interaction of the latter with azathioprine.We therefore prospectively studied the uricosuric efficacy of100 mg benzbromarone (Bbr;Desuric®) daily in 25 CsA-treatedrenal transplant patients with stable graft function and hyperuricaemia(>359 µmol/l for females, >491 µmol/l formales). Benzbromarone decreased plasma uric acid from 579±18µmol/l to 313±24 µmol/l (mean±SEM;P<0.001) and thereby normalized plasma uric acid in 21 of25 patients. The remaining four patients had creatininc clearancesbetween 21 and 25 ml/min, the lowest of the entire study group.Mean fractional clearance of uric acid increased from 5.4±0.4%to 17.2±1.0% (P<0.001). The relative decrease of plasmauric acid closely correlated with baseline creatinine clearance(r=0.67; P<0.001). CsA trough values were not influenced.None of the patients experienced any significant side-effects.As an unexpected find-ing, urinary uric acid excretion increasedfrom 2082 ± 175 µmol7sol;24 h to 3233 ±232µmol/24 h after 4 weeks' treatment with benzbromarone. In conclusion, benzbromarone normalized plasma uric acid inall CsA-treated renal transplant recipients with a creatinineclearance >25 ml/min. Due to its excellent efficacy and lackof significant side-effects, benzbromarone appears to be preferableto allopurinol in CsA-treated renal transplant recipients witha creati nine clearance over 25 ml/min.  相似文献   
59.
环丙沙星治疗急性细菌性痢疾29例临床疗效观察   总被引:5,自引:1,他引:4  
食源性急性菌例29例中28例大便培养为弗氏2a志贺氏菌。经2天吡哌酸加TMP短程快速治疗,29例无一例治愈。依据药敏试验改用环丙沙星治疗,其中11例感染严重者先予静脉点滴,每12小时200mg,1 ̄2天,症状好转即改口服,每12小时250mg。另18例口服,疗程均为4天。用药后,平均退热时间1.32天,大便次数恢复正常时间平均2.10天,大便常规正常时间平均2.86天,28例大便培养阳性者,平均阴  相似文献   
60.
以功效系数为目标函数,相应地确定了设计变量和约束函数,对塑料注塑机合模机构的参数进行优化计算,提高了机构的综合性能。  相似文献   
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