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41.
The manifestation of diurnal periodicity and the extent of its control by the photoperiod was assessed in three predation defense reactions which constitute either components or outcomes of a predator-prey interaction sequence. Two-hundred White Leghorn chicks were reared from hatching for one week in either 24L or 12L and then tested at one of two clock hours previously demonstrated to define peak and trough response for one of the components. Putative evidence was found for an endogenous source of the periodicity manifested in all reactions. Maintenance schedule did not entrain the periodicity, but simple room entry and handling elicited anti-predator reactions, the extent of which varied as a function of clock hour. A general model of predation defense behavior was proposed. 相似文献
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45.
D M Kaufman 《Psychosomatics》1989,30(3):263-269
The face is prominently or exclusively involved in several involuntary movement disorders, called "facial dyskinesias," in addition to the common buccolingual form of tardive dyskinesia. This review describes the appearance of the most frequently occurring facial dyskinesias: chorea, dystonia, tremor, and tics. Some new treatments are discussed. 相似文献
46.
O. Ya. Kaufman Yu. L. Perov A. K. Boikov T. B. Timashkevich 《Bulletin of experimental biology and medicine》1977,84(1):1053-1056
In experiments on rats the ultrastructure of the muscle tissue of the inferior vena cava after disturbance of the outflow of blood, of the muscular coat of the stomach after resection of 50% of its fundus, and of the muscular coat of the cecum after constriction of its ascending portion was studied. Activation of smooth muscles was shown to reflect the phase of injury to the ultrastructure of the cells, followed by processes of intracellular regeneration. Analysis of the ratio between DNA-synthesizing and activated cells showed the local origin of the latter from differentiated myocytes.Institute of General Pathology and Pathological Physiology, Academy of Medical Sciences of the USSR. No. 4 Main Board, Ministry of Health of the USSR. Institute of Human Morphology, Academy of Medical Sciences of the USSR. Moscow. (Presented by Academician of the Academy of Medical Sciences of the USSR A. P. Avtsyn.) Translated from Byulleten' Éksperimental'noi Biologii i Meditsiny, Vol. 84, No. 7, pp. 112–115, July, 1977. 相似文献
47.
Quantitation by electron microscopy of the binding of highly specific antibodies to benzo[a]pyrene-DNA adducts 总被引:1,自引:0,他引:1
Highly specific antibodies bound to carcinogen adducts in DNAmodified with (+ / - )7ß, 8-dihydroxy-9, 10-epoxy-7,8, 9, 10-tetrahydrobenzo[a]pyrene (BPDE I) were quantitatedby electron microscopy (EM) visualization and these observationswere compared with quantitation of adducts by enzyme-linkedimmunosorbent assay (ELISA). The antiserum, elicited in rabbitsfollowing inoculation with BPDE I-modified DNA, has been foundto be highly specific in its recognition of BPDE I-deoxyguanosinemoieties. Parallel DNA samples prepared for analysis by ELISAand EM quantitation were randomized, encoded, and analyzed todetermine extents of carcinogen modification in double-blindstudies. After levels of modification were determined by immunoassays,DNA samples were prepared for EM analysis by incubation withamounts of anti-BPdG-DNA serum in excess of that necessary forcomplete binding of antibody to antigenic sites. At equilibrium,samples were enzymatically digested with papain in order tocleave anti-BPdG-DNA IgG molecules into Fab fragments in situ.Following column exclusion chromatography, BPdG-DNA-Fab complexeswere incubated with ferritin-labeled Fab fragments ofgoat [anti-rabbit F(ab)2] IgG in amounts in excess ofthose necessary for complete binding. When DNA samples weremodified to between 0 and 40 fmol adduct/ µg DNA, excellentagreement was obtained between ELISA quantitation and visualizationby EM of antibodies bound to adducts. 相似文献
48.
Experimental air leaks in lung sealed by low-energy carbon dioxide laser irradiation 总被引:1,自引:0,他引:1
When a focused carbon dioxide laser beam strikes a surface of tissue, the light energy is converted instantly into thermal energy, causing cells directly in the laser's path to vaporize. Because the carbon dioxide laser's energy is well absorbed by water, this thermal effect is attenuated at a distance of 100 mu. If the laser beam is "defocused," the same thermal energy is dissipated over a larger area, causing only desiccation and melting of tissue without vaporization; however, the depth of injury remains shallow. This modified technique has been used to seal artificially created air leaks in the canine lung. Twelve mongrel dogs were anesthetized, intubated, and ventilated. The lingula was exposed sterilely through a left thoracotomy. A 1 X 3-mm hole was made in the lung at 1 cm from the edge. The created air and blood leaks were sealed with a defocused carbon dioxide laser beam set at 8 W (32 W/sq cm). Each tissue "weld" withstood 40 cm H2O of peak ventilation pressure without leak. At the time of reoperation three weeks later, there was apparent complete healing of the pulmonary surface. No air leaks were present. Histologic examination showed a small zone of amorphous coagulated pleura and lung overlying a zone of minimal atelectasis. Normal lung was present within 150 mu of the laser seal. This new technique was performed safely and easily with currently available carbon dioxide lasers in the laboratory. It is presently undergoing intraoperative trials in a controlled clinical setting. 相似文献
49.
D. M. Vogter J. L. Culberson S. S. Schochet O. F. Gabriele H. H. Kaufman 《Acta neurochirurgica》1987,84(3-4):136-139
Summary High spinal (cervical and upper thoracic) dysrhaphism usually involves either a meningocele or a dermal sinus tract. These high spinal lesions can have a complex intradural anatomy at the level of the lesion (as this case reports) and are associated with an increased incidence of lower spinal occult dysrhaphic anomalies. It is therefore recommended that patients with high spinal dysrhaphism undergo radiological evaluation of the entire spine to identify those patients with intradural anomalies, define the anatomy for surgery, and investigate the lower spine for associated occult anomalies. 相似文献
50.
Although the objective of this article was to discuss the specific medically treatable causes of male infertility, the reader will be impressed by the fact that many of the treatments seem less than "specific." The need to treat infections to improve fertility is ill defined. The utilization of a scrotal cooling device as "specific" nonsurgical treatment for varicocele is yet to be defined. Immunologic suppression is indeed a specific form of therapy for a measurable phenomenon; unfortunately, the significance of that phenomenon as well as the best means and location of its assessment are undergoing significant reevaluation. An exciting frontier is the prospect of preventing infertility in the patient undergoing therapy for cancer, thus obviating the need for treatment of the ensuing infertility. Before specific therapies can be anticipated to have a predictable beneficial effect, these areas require active investigation to define the problem more clearly. 相似文献