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31.
In a comprehensive study of 80 patients with vasculitis, 4 had concurrent hepatitis B virus (HBV) infection. Polyarteritis nodosa was present in 2 and in the other 2, cutaneous vasculitis, presenting clinically as palpable or Henoch-Schönlein purpura. In one of these patients skin biopsies demonstrated granular deposits of IgM, C3, C4, and the hepatitis B surface antigen (HBsAg) and electron-dense deposits of aggregated 20-nm particles resembling HBsAg in postcapillary venules. Evidence for circulating HBsAg-immune complexes included increased serum C1q binding activity, decreased serum complement, and a cryoprecipitate containing both HBsAg and IgM anti-HBs. Aggregated 20-nm particles resembling intact HBsAg were also seen by negative staining electron microscopy of the serum cryoprecipitate. This patient fulfills all the criteria for a specific immune complex vasculitis caused by his immune response to a chronic HBV infection. These findings emphasize that HBV infection may be associated with small vessel vasculitis as well as polyarteritis nodosa, mixed cryoglobulinemia, and glomerulonephritis. A similar immune response to other viral infections may be expressed as palpable (Henoch-Schönlein) purpura also.  相似文献   
32.
Two mitochondrial and one nuclear genetic marker were used to study the phylogenetic position of the two reported CO1-genotypes of Caligus elongatus in a group of closely related caligid parasites. Molecular analysis of the two mitochondrial genes (CO1 and 16S), indicate genetic distances of the two C. elongatus genotypes in the lower range of distances previously reported between other crustacean species, but higher than comparable reported within-species differences. Analyses of nuclear 18S sequences indicate no detectable differentiation between these genotypes, but may be due to expected differences in the resolution of these genetic markers. Investigation of two of three selected morphological characters reveals phenotypes supporting the division based on the molecular division. The species status on the two C. elongatus genotypes cannot be drawn conclusively, although the molecular and morphological data presented here suggests the presence of sibling species.  相似文献   
33.
The suppression of skin test reactivity by single doses of six antihistamines was measured before and after a period of daily antihistamine ingestion in 18 subjects. Single doses of hydroxyzine, 50 mg; chlorpheniramine, 16 mg; and promethazine, 50 mg; induced significant suppression of skin test reactivity at 2 hr, whereas the suppression produced by tripelennamine, 100 mg; diphenhydramine, 50 mg; and cyproheptadine, 16 mg; did not differ significantly from that produced by placebo. After 3 wk of treatment with hydroxyzine, 75 mg per day, the suppressive effect of hydroxyzine as well as the five clinically unrelated antihistamines was significantly reduced. Although the response to chlorpheniramine was also reduced after chronic treatment with chlorpheniramine, 24 mg per day, the difference was not statistically significant. We conclude that antihistamines in the doses used differ greatly in their suppressive effect on skin test reactivity. The antihistamine producing the most skin test suppression, hydroxyzine, when it was taken daily for 3 wk, caused the development of partial tolerance not only to its own effect but to those of clinically unrelated antihistamines.  相似文献   
34.
目的:探究人乳头状瘤病毒(HPV)感染并阴道上皮内瘤变(VAIN)患者采用干扰素配合CO2激光治疗的应用效果。方法:选取常德市第一人民医院2017年7月至2019年7月收治的194例HPV感染并VAIN患者,依据随机数字表法分组为A组(64例,采用CO2激光治疗),B组(64例,采用CO2激光配合保妇康栓治疗),C组(66例,采用CO2激光配合干扰素治疗),比较各组患者的疗效。结果:治疗后C组患者的阴道出血量、阴道排液量低于A组、B组,且阴道出血时间、阴道排液时间少于A组、B组,差异具有统计学意义(P <0.05)。治疗后C组患者不同时间段的病变逆转率均高于A组、B组,差异具有统计学意义(P <0.05)。治疗后2年各组患者恶化率比较,差异无统计学意义(P> 0.05)。C组患者的不同时段病变复发率均低于A组、B组,且不同时段HPV转阴率均高于A组、B组,差异具有统计学意义(P <0.05)。结论:干扰素配合CO2激光治疗可显著减轻本研究患者术后阴道出血...  相似文献   
35.
目的 探讨醒脑静对急性重症一氧化碳 (CO)中毒的催醒作用。方法 在急性重症CO中毒常规综合抢救中加入醒脑静并与常规方法进行对比研究。结果 醒脑静治疗组较常规治疗组清醒时间明显缩短 (P <0 .0 1)。结论 醒脑静可作为急性重症CO中毒病人综合抢救中常规用药。  相似文献   
36.
Serge  R  Bitemo  高勇 《医学教育探索》2001,(4):338-340
针对传统RESS过程中存在着颗粒质量和产量问题,本文分别以超临界CO2作为溶剂在萘的固态和熔融状态下利用RESS过程制备了萘的超细颗粒,研究了萘在固态和熔融态下各种操作变量,如萃取温度和压力、膨胀前温度和喷嘴尺寸等对产品尺寸的影响。结果表明,膨胀前温度和萃取压力的作用规律相同,提高膨胀前温度则颗粒变大,提高萃取温度,颗粒尺寸变小;而在熔融状态下反之,在该研究范围内,喷嘴尺寸的熔融态和固态下对颗粒尺寸影响不大。  相似文献   
37.
目的观察轻度过度通气下施行CO2气腹对呼吸和动脉血气的影响.方法行择期腹腔镜胆囊切除术(LC)病人术前快速诱导麻醉,气管内插管后行机械通气,吸入N2O、持续静脉输注异丙酚维持全麻,硬膜外间断给药.分别在诱导前5 min、气腹前1min和气膜后5、10、20、30、40、50、60min及放气后5 min记录各监测值,同时采桡动脉血作血气分析.结果气腹开始后20~60min,呼气末CO2分压(PETCO2)和Co2排出量(VCO2)较气腹前显著升高.气腹开始后,pH值逐渐降低,30 mm时较诱导前显著降低;PaCO2逐渐升高,60min时较诱导前显著升高,但PETCO2、VCO2、PaCo2及pH的变化均在正常范围.在气腹初期,气道压(PAW)较气腹前显著升高,而呼气分钟通气量(MVE)较气腹前明显降低.结论采用异丙酚静脉全麻复合硬膜外麻醉及气腹前适当过度通气的呼吸管理方式在LC中是切实可行的.  相似文献   
38.
Objective: Many methods have been used in an attempt to seal the epineurium and to prevent axonal outgrowth.In this study, the rat sciatic nerves were repaired with CO2 laser, the nerve regeneration and the morphology of spinal anterior horn neurons were investigated. Methods: Seventy-two male Sprague-Dawley rats were randomly divided into 6 groups of 12 rats. The animals were designed to observe the electrophysiology, the histopathology and the morphology of spinal anterior horn neurons. One of the rat sciatic nerve anastomosed with CO2 laser, the contralateral nerve was reconstructed by microsuture technique. At 2, 4, 6, 8 weeks postoperatively, neuromuscular functions, the regeneration of axons and neurons were evaluated by the electro-physiological and histopathological studies. The rats were killed at 4, 6 weeks postoperatively. Results: The recovery of toe spread and myodynamia in laser groups was better than that in suture groups (P<0.05). The latency of foot withdraw caused by radiate heat and neuromuscular conduction velocity in laser groups were faster than that in suture groups (P<0.05). The density of nerve fibers, percentage of axons passing through anastomotic area and numbers of neurons were better in laser groups than in suture groups. At 8 weeks postoperatively, the first grade dendrites of anterior horn neurons grew well. Their diameter, length, volume and total volume were much higher than that in control group. (P<0.05, P<0.01). Conclusion: CO2 laser repairing was effective in promoting the regeneration and the recovery of sciatic nerves in its earlypost-trauma stage. In addition, laser repairing was found to reduce regenerating axons misdirection and forming neuroma.  相似文献   
39.
目的 :探讨全胃肠道促动力药物西沙必利对糖尿病性胃轻瘫 (DGP)的治疗作用。方法 :采用胃电图(EGG)体表描记法 ,分别描记DGP患者治疗前后及对照组EGG的数值 ,间接判断DGP患者治疗前后胃排空功能变化。结果 :治疗前DGP与对照组胃体、胃窦部的平均振幅 (AP)、峰值频率 (FP)均存在显著性差异 (P <0 .0 5或P <0 .0 1)。治疗后 2组比较 ,除胃窦AP外 ,胃体AP、FP及胃窦FP均无显著性差异 (P >0 .0 5 ) ,胃轻瘫患者的临床症状也得到显著改善。结论 :西沙必利是治疗DGP的有效药物。  相似文献   
40.
Polymeric Microspheres Prepared by Spraying into Compressed Carbon Dioxide   总被引:13,自引:0,他引:13  
Purpose. The objective was to prepare polymeric microparticles by atomizing organic polymer solutions into a spray chamber containing compressed CO2 (PCA-process) and to study the influence of various process parameters on their morphological characteristics. Methods. The swelling of various pharmaceutically acceptable polymers [ethyl cellulose, poly(methyl methacrylate), poly(-caprolactone), poly(dl-lactide), poly(l-lactide) and poly(dl-lactide-glycolide) copolymers] in CO2 was investigated in order to find polymers which did not agglomerate during the spraying process. Poly(l-lactide) (L-PLA) microparticles were prepared by spraying the organic polymer solution into CO2 in a specially designed spraying apparatus. The effect of various process (pressure and temperature of the CO2 phase, flow rate) and formulation (polymer concentration) variables on the morphology and particle size of L-PLA-microparticles was investigated. Results. Polymers with low glass transition temperatures agglomerated even at low temperatures. The formation of microparticles was favored at moderate temperatures, low polymer concentrations, high pressures and high flow rates of CO2. High polymer concentrations and low flow rates resulted in the formation of polymeric fibers. Colloidal L-PLA particles could also be prepared with this technique in a surfactant-free environment. Initial studies on the microencapsulation of drugs resulted in low encapsulation efficiencies. Conclusions. The PCA method is a promising technique for the preparation of drug-containing microparticles. Potential advantages of this method include the flexibility of preparing microparticles of different size and morphology, the elimination of surfactants, the minimization of residual organic solvents, low to moderate processing temperatures and the potential for scale-up.  相似文献   
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