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61.
Research has demonstrated considerable heterogeneity in the long-term course of schizophrenia. In the period preceding the onset of frank psychosis (onset), patients vary relative to the rapidity of onset, the presence or absence of associality, and the presence or absence of semipsychotic symptoms. Following the onset of psychosis (middle course), patients may suffer from episodic or unremitting psychosis, and may or may not exhibit the deficit syndrome. In late adult life (late course), patients vary relative to the presence or absence of an improvement in psychosis and social capability. The usual approach to the study of putative course subtypes is to define a subtype by a number of features; they may include features of more than one epoch. In addition, the course of psychosis has not been distinguished from enduring personality impairments in these subtypes. Another approach to defining putative course subtypes would be based on dichotomizing patients according to the presence or absence of a particular feature of a single epoch. This second approach has important advantages: the availability of larger study populations and a diminished liability for confounding due to the correlates of features other than those under scrutiny. 相似文献
62.
R S Owen J P Carpenter R A Baum L J Perloff C Cope 《The New England journal of medicine》1992,326(24):1577-1581
BACKGROUND. Bypass grafting to arteries of the lower leg has become standard surgical management of advanced peripheral vascular disease. Its success depends on identifying suitable distal vessels. Preoperative preparation includes imaging of the arteries of the lower leg, usually by conventional contrast arteriography. An alternative procedure, magnetic resonance (MR) angiography, has been successfully employed in patients with various cardiovascular diseases, but its possible value in patients with peripheral vascular disease has received little attention. METHODS. We used both conventional and MR angiography in preoperative studies of the lower-leg vessels of 23 patients (25 legs) with peripheral arteriosclerosis and arterial insufficiency, and developed independent therapeutic plans based on the information provided by each technique. When the plans differed, the interventional procedure judged more likely to save the limb was performed. The findings of conventional and MR angiography were verified by intraoperative arteriography, postinterventional arteriography, or direct operative exploration. RESULTS. MR angiography detected all vessels identified by conventional angiography, whereas conventional arteriography failed to detect 22 percent of the runoff vessels identified by MR angiography. The detection by MR angiography of vessels not identified by conventional angiography altered the surgical management of the disorders of four patients (17 percent) and guided successful bypass procedures. CONCLUSIONS. MR angiography is a noninvasive technique with greater sensitivity than conventional contrast arteriography for detecting distal runoff vessels in patients with peripheral arterial occlusive disease. 相似文献
63.
超声引导下注射皮质类固醇治疗狭窄性腱鞘炎 总被引:1,自引:0,他引:1
目的 探讨超声引导下注射皮质类固醇治疗狭窄性腱鞘炎的方法及效果。方法 38例狭窄性腱鞘炎患者,按药物注射方法的不同随机分成2组。治疗组(21例)在10-MHz超声引导下向腱鞘内腱周间隙内穿刺注射醋酸强的松龙0.6 ml,对照组(17例)采用闭合穿刺法注射等量药物。注射前及随访时(注射后3周)测定疼痛强度视觉类比评分(Visual analogue score,VAS)。结果 随访时疼痛消失率治疗组为81%、对照组为53%,VAS下降值治疗组为[(6.8±1.9)x±s,下同]对照组为(5.1±3.0)。结论超声引导下将针尖穿刺于腱鞘内腱周间隙的操作简单、准确并可实时观察药物的分布,是治疗狭窄性腱鞘炎的较好方法。 相似文献
64.
We have examined the distribution of phospholipase C-gamma 1 (PLC-gamma 1) between membrane and cytosolic fractions in several cell lines. In MDA-468 cells, which are derived from a human breast tumor, greater than one-half of the total PLC-gamma 1 is associated with the membrane fraction of the cell. Unlike the situation in A-431 cells [G. Todderud, M. I. Wahl, S. G. Ree, and G. Carpenter, Science, 248: 296-298, 1990], epidermal growth factor (EGF) stimulation of MDA-468 cells does not result in significantly increased PLC-gamma 1 association with membranes. Immunoblot analysis reveals low levels of phosphotyrosine in PLC-gamma 1 and EGF receptors in unstimulated MDA-468 cells and greatly increased phosphotyrosine levels in these proteins as a result of EGF stimulation of the cells. We conclude that autocrine activation of EGF receptors is not responsible for the elevated association of PLC-gamma 1 with membranes in these cells. 相似文献
65.
目的探讨羟乙基淀粉130/0.4预充液对先天性心脏病患儿围体外循环期血管内皮细胞(VEC)及血管通透性的影响。方法择期体外循环(CPB)下行心内直视手术的先天性心脏病患儿40例,ASAⅡ或Ⅲ级,男19例,女21例,年龄5~18岁,随机分为2组(n=20):血浆组(对照组)和羟乙基淀粉130/0.4组(试验组)。对照组预充乳酸林格氏液和血浆,试验组预充乳酸林格氏液和羟乙基淀粉130/0.4。胶体预充液用量18-33 m1·kg-1,晶体:胶体=0.60-0.70。分别于转流前即刻(T1)、转流30min(T2)、转流结束即刻(T3)、转流结束6 h(T4)、术后第1天清晨(T5)检测血浆循环内皮细胞(CEC)数量、内毒素、可溶性细胞间粘附分子-1(sICAM-1)、肿瘤坏死因子-α(TNF-α)及尿微量白蛋白(U-Mal)浓度。结果.T1时两组CEC、内毒素、sICAM-1、TNF-α、U-Mal差异无统计学意义(P>0.05)。CEC:两组T2、T3及T4时较T1增高,T4时试验组低于对照组(P<0.05)。内毒素:两组T2、T3、T4时较T1升高,T3、T4、T5时试验组低于对照组(P<0.05)。sICAM-1:对照组T4、T5时较T1升高,T4时试验组低于对照组(P<0.05)。TNF-α:对照组T3时较T1升高,试验组低于对照组(P<0.05)。U-Mal:两组T4时较T1升高,试验组低于对照组(P<0.05)。结论羟乙基淀粉130/0.4预充液对先天性心脏病患儿围体外循环期VEC及其功能具有保护作用。 相似文献
66.
Mark N. Bodily Randall L. Carpenter Brian D. Owens 《Journal canadien d'anesthésie》1992,39(8):770-773
The efficacy of subarachnoid injection of 8 ml lidocaine 0.5% was assessed in ten outpatients having perirectal surgery in the jackknife position. This solution is hypobaric, with a baricity 0.9985 +/- 0.0003 (mean +/- SD). Injections were made with the patient in the surgical position (with the upper torso at a 15 degrees downward inclination). Sensory level was tested by pinprick. Times to two-segment regression, to complete resolution of sensory analgesia, to urination, and to discharge from the recovery room were recorded. All injections produced effective anaesthesia for surgery. Lidocaine 0.5% behaves clinically as a hypobaric solution. Dermatomal levels remained low (T11 to L5) while the patients were in the surgical position (head down), but rose two to six dermatomes if the patient's head was elevated after surgery. Time to two-segment regression was 97 +/- 36 min, time until regression to S1 was 116 +/- 22 min, time to complete resolution of sensory blockade was 151 +/- 23 min, time to urination was 197 +/- 64 min, and time to discharge from the recovery room was 205 +/- 45 min. Lidocaine 0.5% provides effective spinal anaesthesia of short duration appropriate for outpatient surgical procedures. Dermatomal sensory spread of anaesthesia, and our measurements of specific gravity, indicate that this solution is hypobaric. It appears that changes in position can alter the spread of analgesia for at least one hour after injection and, thus, we caution against elevating the patient's head in the immediate postoperative period. 相似文献
67.
L H Lin S Bock K Carpenter M Rose J J Norden 《Brain research. Molecular brain research》1992,14(1-2):147-153
Metabolic labeling and quantitative 2D gel autoradiography were used to assess changes in the synthesis and transport of GAP-43 in entorhinal cortex (EC) neurons and perforant pathway during lesion-induced sprouting and reactive synaptogenesis. In normal adult rats, there is a high constitutive level of GAP-43 synthesis and transport in EC neurons projecting to the hippocampus. Following unilateral EC lesions, there is a 2-fold (100%) increase in the transport of newly synthesized GAP-43 to the contralateral or 'sprouting' hippocampus. The timing of this upregulation (between 6 and 15 days) suggests that changes in GAP-43 expression occur in response to the growth of presynaptic terminals during sprouting. 相似文献
68.
以光敏生物素标记的R3 cDNA克隆为模型,采用正交设计的方法,对影响核酸杂交反应的主要因素:杂交反应温度,反应时间,探针浓度及甲酰胺浓度作了综合性分析。当探针浓度为800μg/L,甲酰胺浓度为10mol/L,50℃杂交反应6h,可获得最高灵敏度(10pg)。 相似文献
69.
The thesis of this article is that since followup studies of patients with schizophrenia have provided a rich body of informative knowledge, emphasis should now be on hypothesis testing in future studies. The consumer of research needs to have a general appreciation of statistical thinking, design, and methods to make an informed synthesis of results presented. This article presents a brief discussion of relevant statistics and statistical issues, as free of jargon as possible. Given the multivariable nature of psychiatric research, the natural focus is on multivariate statistics. A strong background in statistics is not required to understand the methods described and how and why they might be applied. Reference material for more detailed discussions is provided. It is a truism to say that the highest quality scientific work is dependent on an intimate collaboration with the expert in statistics and the expert in clinical methods, and this merits repeating only because it is so often ignored. 相似文献
70.
To investigate the effects of training frequency and specificity of training on isolated lumbar extension strength, 72 men (age = 31 +/- 9 years) and 42 women (age = 28 +/- 9 years) were tested before and after 12 weeks of training. Each test involved the measurement of maximum voluntary isometric torque at 72 degrees, 60 degrees, 48 degrees, 36 degrees, 24 degrees, 12 degrees, and 0 degrees of lumbar flexion. After the pretraining tests, subjects were randomly stratified to groups that trained with variable resistance dynamic exercise every other week (1X/2 weeks, n = 19), once per week (1X/week, n = 22), twice per week (2X/week, n = 23) or three times per week (3X/week, n = 21); a group that trained isometrically once per week (n = 14); or a control group that did not train (n = 15). Analysis of covariance showed that all training groups improved their ability to generate isometric torque at each angle measured when compared with controls (P less than 0.05). There was no statistical difference in adjusted posttraining isometric torques among the groups that trained (P greater than 0.05), but dynamic training weight increased to a lesser extent (P less than 0.08) for the 1X/2 weeks group (26.6%) than for the groups that trained 1X/week, 2X/week, and 3X/week (37.2 to 41.4%). These data indicate that a training frequency as low as 1X/week provides an effective training stimulus for the development of lumbar extension strength. Improvements in strength noted after isometric training suggest that isometric exercise provides an effective alternative for developing lumbar strength. 相似文献