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911.
A new Soviet laser device for multiple-purpose ophthalmologic application is described. The design is based on neodymium-doped glass laser with radiation at a 1.06 micron wavelength in a Q-spoiled mode and YAG laser with radiation frequency doubling at a wavelength of 0.532 micron in continuous operation. Clinical potentialities of this laser design in the treatment of abnormalities of the anterior and posterior segment of the eye were studied in the treatment of 48 patients (48 eyes). The results evidence that the device is fit for coagulation as well as for mechanical destruction of tissue. 相似文献
912.
School-Based Cardiovascular Health Promotion: The Child and Adolescent Trial for Cardiovascular Health (CATCH) 总被引:7,自引:0,他引:7
Cheryl L. Perry PhD Elaine J. Stone PhD MPH FASHA Guy S. Parcel PhD FASHA R. Curtis Ellison MD Philip R. Nader MD FASHA Larry S. Webber PhD Russell V. Luepker MD MS 《The Journal of school health》1990,60(8):406-413
The Child and Adolescent Trial for Cardiovascular Health (CATCH) is a multisite intervention research study that builds on significant progress made in school health education research in the 1980s. The study has three phases: Phase I deals with study design, intervention, and measurement development, Phase II involves the main trial in 96 schools in four states, and Phase III focuses on analysis. The intervention program targets third-fifth grade students and focuses on multiple cardiovascular health behaviors, including eating habits, physical activity, and cigarette smoking. Classroom curricula, school environmental change, and family involvement programs are developed for each grade level and behavioral focus. This paper describes Phase II of CATCH with a rationale for cardiovascular health promotion with youth. The process of change that appears to be necessary for school-based health promotion and that will be tested in CATCH are presented as a framework to guide these efforts. 相似文献
913.
914.
Exposing embryos to elevated temperatures both in vivo and in vitro has been shown to result in the production of offspring with severe congenital abnormalities. While a direct effect of heat cannot be excluded, recent interest has been focused on the possible role that the induction of the heat shock response may have in the etiology of the observed congenital defects. In the present study, mouse embryos from inbred strains known to differ in terms of their sensitivity to heat-induced exencephaly were treated in vivo and their heat shock response determined using SDS-PAGE electrophoretic techniques. Further, the embryonic responses were compared with a maternal cell type. We observed excellent agreement between the two test systems following exposure to a teratogenic hyperthermic insult. Both the embryonic and maternal cells underwent a reduction in total protein synthesis and an enhanced synthesis of four heat shock proteins migrating with the molecular weights of 68, 70, 97, and 110 kDa. The results failed to indicate any strong correlation between the heat shock response and enhanced genetic sensitivity to hyperthermia-induced neural tube defects. 相似文献
915.
The results of examination of 575 solitary spherical structures in the lungs are analysed. Comparative evaluation of various methods of examination showed that transthoracic aspiration biopsy conducted under the control of computered tomography by means of two thin needles has advantages over radiological examination, cytological examination of sputum, and bronchofibroscopic biopsy. The authors developed a diagnostic algorithm used in a patient with a solitary spherical structure in the lung. 相似文献
916.
917.
918.
The development of a unifying framework for conceptualizing the commonalities in various forms of substance abuse must encompass the data base focused upon the stimulus functions of drugs. In the first instance, for example, the research on drug self-administration has provided convincing evidence of a remarkable concordance between laboratory animals and human substance abusers in the reinforcing stimulus functions of a range of chemical agents. The recognition of these cross-species and cross-drug generalities has radically changed conceptualizations of substance abuse from a reactive to a more active process and has encouraged the kind of functional analysis of drug-seeking and drug-taking that has proven productive and useful in the study of other behavioral interactions. In this regard as well, recent refinements in the analysis of the discriminative stimulus functions of drugs have provided a more comprehensive basis for characterizing a chemical agent's spectrum of action and evaluating its abuse liability. While the correlation between the discriminative stimulus functions and the reinforcing stimulus functions is remarkably high for some drug classes, there are notable exceptions. Finally, the assessment of abuse liability requires an analysis of the eliciting stimulus functions of drugs as reflected by the physiological and behavioral changes, both acute and chronic, that follow drug administration. The methods used to evaluate both physiological dependence and behavioral toxicity in relationship to sensory and motor effects for a range of abused drugs have depended heavily upon an assessment of the eliciting stimulus functions of such compounds. 相似文献
919.
F V Galimzianov 《Khirurgiia》1990,(5):108-110
Comparative analysis of outpatient treatment by means of pulsed complexly-modulated electromagnetic field (PCMEMF) applied after phlebectomy in 30 patients with varicosity of the lower limbs showed the expediency of this type of treatment in the postoperative period. Exposure of the operated on limb to PCMEMF raises the efficacy of the rehabilitation measures and reduces the terms of the patients' temporary incapacity. 相似文献
920.
During a 9 month period, 50 consecutive children were evaluated by ultrasound to determine the size, location (mesenteric vs para-aortic), number, shape and texture of abdominal lymph nodes in a normal paediatric population. High resolution linear array transducers were used with graded compression. Nodes ranging from 10 to 20 mm were recorded in the majority of subjects. In all cases mesenteric lymph nodes were larger and more numerous than para-aortic nodes. Para-aortic lymph nodes were not seen in isolation. 相似文献