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11.
In order to carry out investigations in the course of sport activities of children an efficient telemetering device is essential, which can also be used on children. The Kinderspital Salzburg has developed a telemetry system in cooperation with the Technische Versuchs- und Forschungsanstalt der Technischen Hochschule Wien and the Messerschmitt-B?lkow-Blohm-Werke München. For the first time in this field a Pulse Code Modulation (P.C.M.) System was utilized, implying high accuracy on data transmission and recovery as required for scientific examinations. The children's physical capacity is determined on a bicycle ergometer, and the performance measured in this fashion is then compared with the performance achieved in sport.  相似文献   
12.
Purified rat liver nuclei covalently bound low levels of seven aromatic [14C]hydrocarbons to nuclear DNA. Induction with 3-methylcholanthrene increased the binding of six carcinogenic hydorcarbons, but did not raise the level of binding of noncarcinogenic anthracence. Removal of the nuclear envelope by Triton N-101 eliminated binding and aryl hydrocarbon hydroxylase activities and cytochrome P-450 from the nuclei. Binding of two of two strong carcinogens, benzo[a]pyrene and 7,12-dimethylbenz[a]anthracene, to nuclear DNA was compared to the levels of aryl hydrocarbon hydroxylase and cytochrome P-450 in nuclei from uninduced and benz[a]anthracene-, 3-methylcholanthrene-, and phenobarbital-induced rats. Microsomal hydroxylase and cytochrome P-450 were also assayed. Induction with 3-methylcholanthrene gave the largest increases in nuclear activities: 11 times as much hydroxylase, 6 times as much cytochrome P-450, and 4 times as much binding of both hydrocarbons. Benz[a]anthracene and phenobarbital induced these nuclear activities 0- to 4-fold. In the presence of added NADPH, binding of benzol[a]pyrene to DNA by nuclei increased rapidly for at least 20 min. When NADPH was not added, the reaction stopped at a low level in 5 min. When CO was bubbled through the reaction mixture with or without added NADPH, binding of benzo[a]pyrene and 7,12-dimethylbenz[a]anthracene was partially inhibited, indicating that cytochrome P-450 plays a role in this activation. Since no nuclear hydroxylase activity was seen without added NADPH or in the presence of CO, activation and subsequent binding of hydrocarbons to nuclear DNA, at least in part, does not require the activated oxygen used in monooxygenase reactions.  相似文献   
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Striated muscle fibers (or cells) were observed in three of the six swine pineal glands. The muscle fibers occurred in clusters of several fibers about the parenchymal blood vessels. They were in general poorly developed, lacked regular cross striations and were not readily recognized histologically. The muscle fibers were, however, easily identified on electron microscopy because of the myofilaments they contain. In most of the muscle fibers, the myofilaments were arranged in ill-defined, disorderly bundles and rarely formed well-defined myofibrils and sarcomeres. The sarcotubular system was also poorly developed and triads were sparse and randomly scattered. Leptomeres were observed in several muscle fibers. The source of the muscle fibers in the pineal glands is not well understood and, whatever the source may be, the muscle fibers seem to remain poorly developed in the pineal glands.  相似文献   
15.
In the gynecological department of Rostov Oncological Institute endolymphatic polychemotherapy with a preliminary determination of tumor sensitivity to chemotherapy was employed in 54 patients with cervical cancer, 3 of them in stage III and IV having contraindications to radiotherapy. A combination of chemical substances and the dosage of single administration were as follows: thio-TEPA--100--150 mg + methotrexate 75--100 mg; thio-TEPA--100--150 mg + 5-fluoruracil--1000 mg; cyclophosphane--2000 mg + methotrexate--75--100 mg; cyclophosphane--1600 mg + methotrexate--75--100 mg + 5-fluoruracil--750 mg. Lymphoinfusion was made in the lower extremity, and after 7--10 days it was repeated in the second one. Visual disappearance of the tumor was noted in 17 patients, lessening of the tumor size by two-thirds--in 16, a 1/2 decrease--in 20. Among 23 patients in stage III after the treatment parametrial infiltrations disappeared entirely in 11 cases and only in pelvic walls--in 12. In 40 cases an extensive extirpation of the uterus with adnexa was performed. In all cases degenerative changes in tumor tissues were observed, whereas in 7 cases no tumor cells were found.  相似文献   
16.
Anterograde and retrograde tracing experiments have been used to demonstrate the origin and terminal distribution of commissural fibers in the first somatosensory cortex (SI) of the rat. The commissural fibers originate from pyramidal cells of all layers, but predominantly from layers III and V. The fibers terminate in a series of approximately vertical bands. In each of these there are concentrations of terminals extending from the inner portion of the molecular layer to the deep portion of layer III as well as in the superficial part of layer V, and in layer VI. Discrete vertical bands of cortex are reciprocally connected across the midline to give both the origin and terminal regions of the projection a patchy or "columnar" appearance. The commissural fibers arise from and terminate in areas of the cortex that lie between and alongside the aggregations of granule cells that distinguish SI of the rat. No commissural fibers terminate within the aggregations of layer IV cells themselves but the more superficial terminal ramifications may come to overlie these aggregations. A heterotopic projection to the contralateral second somatosensory cortex has been observed and is similar in form to the homotopic projection to SI. Many commissural fibers have crossed the midline in the corpus callosum by the day of birth but lie in the underlying white matter and do not enter the cortical plate until at least the third postnatal day. During the first postnatal week these fibers grow somewhat diffusely into the maturing cortex and their topographic and laminar pattern of distribution attains its adult characteristics by the end of the first week. Commissural axons, thus, arise from immature cells but the maturation of cell form seems to precede the ingrowth of these axons and the acquisition of commissural synapses.  相似文献   
17.
The use of photodynamic dye and light inactivation for the treatment of genital herpes simplex virus infections has been associated with the risk of potential oncogenesis. Sixteen patients treated with neutral red and fluorescent light for documented herpetic infections were studied at intervals ranging from 9 to 52 months following treatment. Four patients treated with other modalities were included in the study. Biopsies of the treated areas were obtained, and 3925 tissue sections were examined. Mild atypical epithelial changes were focally present in most specimens regardless of therapy. Histologically identifiable premalignant change could not be demonstrated.  相似文献   
18.
Cardioacceleration produced by operant conditioning was associated with elevation of plasma renin activity. This study suggests that emotional stimuli, which produce cardioacceleration, may also cause increased renin secretion, thus providing a mechanism by which factors operating through the mind and sodium intake could summate in the production of hypertension.  相似文献   
19.
A method for affinity chromatography of plasma and platelet factor XIII has been developed, based on known structural characteristics of these molecules. Plasma factor XIII is composed of a and b subunits which are held together by noncovalent interactions; platelet factor XIII has only a subunits. a subunit contains free sulfhydryl groups, while in b subunit all the cystines form disulfide bonds. The affinity gel is an organomercurial agarose with p-chloromercuribenzoate as the reactive group. Both the zymogen and activated forms of a subunit reversibly bind to the ligand by forming covalent mercaptide bonds and are eluted by reducing agents. b subunit does not bind to the affinity gel and is held to it only through interaction with a subunit. Affinity chromatography can be used to purify plasma and platelet factor XIII and to study interactions of the subunits. Experiments on the affinity chromatography of purified plasma factor XIII in several stages of activation agree with earlier observations that activation is a two-step procedure in which b subunit is not quantitatively released from the complex until the final stage of activation by Ca2+.  相似文献   
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