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81.
Torsades de pointes is a rare arrhythmia characterized by its bradycardia dependence and increased adrenergic discharge, whether it occurs as a congenital anomaly or as an acquired problem resuiting from drug intoxication or other conditions. There are no reliable tests to assess the propensity toward torsades de pointes or evaluate the efficacy of treatment in these patients. Adenosine can result in marked slowing of sinus and ventricular rate and leads to increased sympathic discharge when given intravenously. We induced torsades de pointes in a child with congenital long QT syndrome (Jervell-Lange-Nielsen syndrome) using 200 μg/kg IV adenosine bolus. Higher dosage of adenosine (600 μg/kg) did not lead to torsades de pointes after β blockade. Adenosine may induce torsades de pointes in patients with the long QT syndrome and may be used as a test to reproduce the clinical arrhythmia. Whether adenosine proves to be useful for assessing the efficacy of treatment will require extensive investigation in larger series of patients.  相似文献   
82.
As demand for a youthful appearance has increased, various techniques for face lifting and contouring have been used to reduce excess fat deposition and improve skin laxity. Recently, radiofrequency (RF)-assisted lipolysis and liposuction (RFAL) has been introduced for body and face contouring. This study aimed to evaluate the clinical improvement and safety of a new RFAL device for face lifting and contouring. A prospective study was conducted in 20 Korean patients who underwent an internal real-time thermosensing monopolar RFAL procedure. Prior to treatment and 12 and 24 weeks after treatment, digital photographs were taken, and the degree of improvement as measured by investigators and patients was recorded. Skin elasticity was measured using a Cutometer (CT575, Courage and Khazaka®, Cologne, Germany). Safety profiles were also evaluated at each visit. Results showed favorable improvement in skin laxity and fat deposition. Both investigators’ evaluations and patients’ evaluation showed significant improvement between 12 and 24 weeks. Although the changes in skin elasticity measured by the Cutometer were not statistically significant, all three treated regions showed a trend toward improvement. No major side effects such as infection or burn were observed. The internal, real-time thermosensing monopolar RFAL device showed clinical efficacy and safety. After further studies with more patients and longer follow-up periods, internal real-time thermosensing monopolar RF devices might become one of the popular treatment options for face lifting and contouring.  相似文献   
83.
Computed tomography of absent left pericardium   总被引:2,自引:0,他引:2  
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84.
The potential laboratory and clinical utility of proton chemical shift imaging (PCSI) was evaluated by studying fatty liver change in rats, which offered a simple animal model for tissue lipid buildup. There was excellent correlation between lipid group signal intensities from in vivo PCSI studies and liver triglyceride levels obtained from in vitro measurements (R = 0.97). The in vivo T1 relaxation time measurements in fatty liver tissue demonstrated two distinct populations of nonexchanging protons. We explain the reason for the lack of sensitivity in conventional magnetic resonance (MR) imaging studies of fatty liver change and discuss the implications of our findings for MR imaging studies of other tissues. PCSI promises improved diagnostic sensitivity and specificity in studying a wide range of human pathologic conditions.  相似文献   
85.
The effect of alcohol ingestion upon the development of naturally occurring and stilbestrol-induced arteriosclerosis was studied in the domestic fowl. In two experiments, a 15 per cent ethyl alcohol solution was used for drinking purposes, and in a third experiment wine containing 12 per cent of it was administered. The caloric intake of both food and alcohol was carefully controlled by pair-feeding, a glucose solution being used for drinking purposes to equalize the caloric intakes of the control birds with those of the alcohol-treated birds. A total of 224 cockrels was studied, and the period of observation for each experiment lasted 12 months. The degree of arteriosclerosis in the thoracic and abdominal aortas was determined in the gross and microscopically, and the degree of lipide infiltration was determined microscopically. The gross grading of arteriosclerotic lesions agreed closely with the microscopic analysis of intimal thickening and lipide infiltration of the arterial wall. The gross gradings were subjected to a critical statistical analysis which allowed precise statements to be made on the probability that a real effect would be overlooked. This analysis yielded no evidence that alcohol or the wine used had affected the degree of gross arteriosclerosis or lipide infiltration.  相似文献   
86.
87.
A new experimental procedure for the production of arteriosclerosis in the bird is described. The subcutaneous implantation of diethylstilbestrol by means of which a sustained increase in the concentration of cholesterol, phospholipid, and neutral fat can be readily established, is shown to induce atherosclerosis of the aorta. The atherosclerosis has been compared with that artificially induced in the bird by the prolonged feeding of cholesterol and also with that occurring spontaneously. The stilbestrol-induced lesion more closely resembled the spontaneously occurring one in the bird than did that produced by cholesterol feeding. But all 3 lesions were fundamentally similar, differing only in the amounts and proportions of the various lipid constituents present. The concentrations of cholesterol in plasma of the stilbestrol-treated and cholesterol-fed birds were of the same order. Yet cholesterol constituted a greater proportion of the lipids deposited in the arterial wall of the cholesterol-fed than in that of the stilbestrol-treated birds. This finding suggests that the cholesterol content of the vascular lesion depends not only on the absolute concentration of cholesterol in plasma, but also on the proportion of cholesterol to other lipid constituents in plasma.  相似文献   
88.
<正>1984年,Sir Alec Jeffreys教授在人类基因组中发现了DNA的高度可变重复片段,即小卫星(minisatellites),与其他的DNA序列相比,这些"小卫星序列"  相似文献   
89.
90.
Cohen IL, Liu X, Lewis MES, Chudley A, Forster‐Gibson C, Gonzalez M, Jenkins EC, Brown WT, Holden JJA. Autism severity is associated with child and maternal MAOA genotypes. We replicated and extended a previously reported association between autism severity and a functional polymorphism in the monoamine oxidase A (MAOA) promoter region, MAOA‐uVNTR, in a sample of 119 males, aged 2–13 years, with autism spectrum disorder from simplex families. We demonstrated that (i) boys with the low activity 3‐repeat MAOA allele had more severe sensory behaviors, arousal regulation problems, and aggression, and worse social communication skills than males with the high activity allele; and (ii) problems with aggression, as well as with fears and rituals, were modified by the mothers' genotype. Boys with the 4‐repeat high activity allele who had homozygous 4‐repeat mothers showed increased severity of these behaviors relative to those born to heterozygous mothers. These findings indicate the importance of considering maternal genotype in examining associations of MAOA and other genes with behavior in male offspring.  相似文献   
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