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31.
The literature on theories of the etiology of schizophrenia (the "nature-nurture dilemma") is reviewed, and the rationale is explicated for a study comparing the development and outcome of kibbutz- and town-reared children of schizophrenic parents. Various possible outcomes of the kibbutz-rearing experience in vulnerable children are discussed. The research team and the time table are described. 相似文献
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Petit mal (absence) epilepsy remains one of the most enigmatic of neurological disorders, and there is no widely accepted theory of its etiology. This review covers some of the current issues concerned with the disorder, including treatment and prognosis, neurochemical research, behavioral and psychophysiological effects of wave-spiked discharges, and EEG studies of seizure control. With respect to treatment, although effective drug therapy (valproic acid, ethosuximide) exists for the "pure" form of absence epilepsy, other forms, in which there is an admixture of grand mal seizures, are less amenable to pharmacotherapy. Moreover, the frequency of fatal hepatic toxicity following valproic acid therapy has been estimated at 1 in 20,000. With respect to prognosis, follow-up studies indicate that many patients do not outgrow the disorder but continue to suffer absence seizures well into adulthood. In recent years, there has been considerable research on the neurochemical basis of absence epilepsy. Current theories, including those that implicate gamma-aminobutyric acid, catecholamines, and "endogenous" epileptogens, are summarized; and requirements for an experimentally induced animal model of absence epilepsy are discussed. The majority of behavioral studies of the disorder have concerned the effects of petit mal-type discharges on sensory and cognitive processes. Some of these studies are reviewed; and recent work bearing on these issues, involving event-related brain potentials, is presented. Our review concludes with a discussion of research aimed at the development of electrophysiologically based approaches to the reduction of seizure frequency in patients with absence epilepsy. 相似文献
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M. Teresa Gómez Hernández Marta Fuentes Gago Nuria Novoa Valentín Israel Rodríguez Alvarado Marcelo F. Jiménez López 《Cirugía espa?ola》2021,99(6):421-427
IntroductionRobotic surgery has become a safe and effective approach for the treatment of pulmonary surgical pathology. However, the adoption of new surgical techniques requires the evaluation of the learning curve. The objective of this study is to analyze the learning curve of robotic anatomical lung resections.MethodsRetrospective analysis of all robotic anatomical lung resections performed by the same surgeon between June 2018 and March 2020. The learning curve was evaluated using CUSUM charts to estimate trend changes in surgical time, surgical failure and the occurrence of post-operative cardiorespiratory complications throughout the sequence of cases.ResultsThe study included a total of 73 cases. The median duration of all complications was 120 min (interquartile range: 90-150 min), the prevalence of surgical failure was 23.29%, while 4/73 patients had any postoperative cardiorespiratory complication. Based on the CUSUM analysis, the learning curve was divided into 3 different phases: phase i (from the first to the 14th intervention), phase ii (between the 15th and 30th intervention) and phase iii (from the 31st intervention).ConclusionsThe learning curve for robotic anatomical lung resections can be divided into 3 phases. The technical competence that guarantees satisfactory perioperative outcomes was achived in phase iii from the 31st intervention. 相似文献
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Metabolism and elimination of rhodamine 123 in the rat 总被引:1,自引:0,他引:1
Trevor W. Sweatman Ramakrishnan Seshadri Mervyn Israel 《Cancer chemotherapy and pharmacology》1990,27(3):205-210
Summary Little is known of the pharmacology of rhodamine 123 (RH-123), an agent reported to have carcinoma-selective experimental antitumor activity. Accordingly, using a high-performance liquid chromatographic assay system with fluorescence detection, we examined the plasma decay and the biliary and urinary elimination of parent drug and metabolites in female Sprague-Dawley rats receiving RH-123 at an intravenous dose (5 mg/kg) equivalent to the therapeutic dose used in murine tumor models. Following drug administration to unconscious animals, plasma levels of drug-associated fluorescence fell in a triphasic manner (t1/2, 15 min; t1/2, 1 h; t1/2, 4.7 h). In plasma, unchanged drug predominated but lower levels of the deacylated metabolite rhodamine 110 (RH-110) and two unknowns were also detectable throughout the study. Drug fluorescence was recovered extensively in both urine and bile. In unconscious animals with ureteral cannulae, urinary excretion (11.4% of the dose in 6 h) occurred predominantly as unchanged RH-123 (97% of the total), with low levels of RH-110 (2.4%) and two unknowns (<0.6% combined) also being present. Similarly dosed conscious animals (without surgical intervention) housed in metabolic cages showed a comparable pattern of urinary excretion, with 11.9% of the drug dose being recovered in 6 h and 21.9%, by 48 h. Biliary drug elimination accounted for 8% of the delivered dose in 6 h in unconscious animals and for 11% by 36 h in conscious animals fitted with biliary cannulae. In contrast to urinary excretion, in which unchanged drug predominated, only 50% of the fluorescence recovered in bile was attributable to RH-123. The remainder was due to a number of products that were detectable throughout the study. Of these, one present at significant levels was identified as a glucuronide conjugate of RH-123, based on the liberation of parent drug when the purified metabolite was incubated with -glucuronidase or hydrolyzed with 1 N hydrochloric acid. Further studies with a radiolabeled form of RH-123 are necessary to establish the identity of the remaining unknowns disclosed in this work.This work was supported in part by research grants CA 44890 (T.W.S.) and CA 37082 (M.I.) from the National Cancer Institute, National Institutes of Health, United States Public Health Service 相似文献
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Gladys Morales Samuel Durán-Agüero Solange Parra-Soto Leslie Landaeta-Díaz Valeria Carpio Brian Cavagnari Israel Rios-Castillo Edna Nava-González Jhon Bejarano-Roncancio Beatriz Núñez-Martínez Karla Cordón-Arrivillaga Eliana Meza-Miranda Saby Mauricio-Alza Georgina Gómez Gabriela Murillo Jacqueline Araneda-Flores 《American journal of human biology》2023,35(8):e23900
40.
The purpose of this study was to identify the frequency of staff stressors and their association with programmatic factors in 51 AIDS prevention and service projects funded by the Robert Wood Johnson Foundation. The methodology included both quantitative (i.e. closed-ended survey questions) and qualitative (i.e. in-depth, open-ended interviews) data to identify the important sources of staff stress. The findings suggest that staff working in AIDS prevention and service projects perceive significant levels of stress regardless of project focus. The most frequently reported staff stresses were too much work, rapid organizational growth, burnout, and problems with staff retention and communication. Among the issues rarely reported as a source of staff stress were too little work, discomfort with the target population and personal health risk concerns. The programmatic factor most often associated with staff stress was obtaining additional funding. Health education interventions need to take a comprehensive approach that includes altering the psychosocial-environmental conditions that give rise to stressors and strengthening the individual and organizational factors that may modify the effects of stress on the AIDS workforce. 相似文献