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Studies were performed to determine the effects of PTH and related compounds on phosphatidylcholine (PC) hydrolysis in UMR-106 cells and the pathway by which the PTH effects occurred. The responses were compared with those of phorbol 12,13-dibutyrate (PDBu). Both bovine PTH-(1-34) [bPTH-(1-34)] and PDBu stimulated PC hydrolysis within 10 min. Significant effects were elicited by concentrations of 0.3-1 nM bPTH-(1-34) and 5 nM PDBu. Dose-dependent increases were seen at higher concentrations of both compounds, however, the response to bPTH-(1-34) was reduced at 30 nM. Bovine or human PTH-(1-34) and human PTH-related peptide-(1-34) [hPTHrP-(1-34)] were equipotent in their effects, whereas bovine [Nle(8,18)Tyr34]PTH-(3-34) amide [bPTH-(3-34)] and hPTH-(1-31) amide [hPTH-(1-31)] were less potent than bPTH-(1-34). bPTH-(3-34) did not antagonize the effects of bPTH-(1-34). Down-regulation of protein kinase C isozymes by 24-h treatment with PDBu completely prevented the stimulatory effect of PDBu on PC hydrolysis, but did not significantly affect the stimulatory effect of bPTH-(1-34). Both bPTH-(1-34) and PDBu stimulated transphosphatidylation of PC, indicating a phospholipase D-stimulated mechanism. The results suggest that in the UMR-106 cell line PTH can stimulate activation of PLD by a mechanism other than through protein kinase C.  相似文献   
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Growth-inhibitory activities of selected natural benzofurans (4-9), trans-cinnamic acid derivatives (10-13), chromene compounds (14 and 16), and some semisynthetic derivatives were determined in last instar larvae of Tenebrio molitor via topical administration in Me2CO. The most inhibitory of the tested compounds were 3-gamma, gamma-dimethylallyl-p-coumaric acid (10) and the benzofuran derivative 12-(p-cumaroyloxy)-tremetone (5), the former compound acting on the pupae and the latter on the last instar larvae. Several developmental deficiencies were observed, and some structure-activity relationships are discussed.  相似文献   
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The dynamic studies of P300 component of the acoustic evoked potential were conducted in 12 patients in posttraumatic state of the autonomic system. The amplitude and time parameters of P300 were analyzed, its spatial distribution over the cortex, and features of generation. The obtained results were compared with the normative data. Significant changes in P300 in comparison with the normal characteristics were revealed in patients with the absence of conscious mental activity. These changes were maximally expressed when the state of patients was irreversible. In case of patients' outcome from the studied state the amplitude-temporal and topographic response characteristics tended to normalization but did not reach it completely. The obtained results allow us to consider the P300 component as one of the most informative indices in consciousness recovery after severe brain injury.  相似文献   
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OBJECTIVE: To identify prognostic factors for penile cancer and to evaluate the treatment strategy for early-stage disease, proposed recently by the European Board of Urology (EBU). PATIENT AND METHODS: The records of 82 patients consecutively referred to the uro-oncological centre at Aarhus University Hospital between 1965 and 1993 were reviewed. The importance of tumour stage, differentiation, patient age, local control and regional lymph node control were assessed using univariate and multivariate analyses. RESULTS: Cox multivariate analysis identified differentiation (odds ratio [OR] = 6.04), UJCC-1978 T-stage (OR = 1.88) and age (OR = 1.04) as independent prognostic variables for survival. Penile amputation in tumours < 4 cm in diameter improved local control but not survival. Regional control and survival were not significantly improved by prophylactic adenectomy. CONCLUSION: Differentiation, T-stage and age were prognostic factors for survival. The results support the EBU treatment strategy involving penis-conserving therapy and watchful waiting for early-stage disease.  相似文献   
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In the present study effects of light on the sleep duration of anesthetized hornets (Vespa orientalis) were investigated. Following initial anesthesia by diethyl ether the sleeping time of workers and drones at 22 degrees C in the dark was 59 +/- 15 min. After repeated anesthesia the sleeping time was 30 +/- 15 min in the dark. When exposed to polychromatic light from a halogen lamp of 230 mW/cm2, focused on a spot of the cuticle of the hornet, the sleeping time was markedly shortened so that following initial as well as repeated anesthesia the hornets woke up after 4.5 +/- 2.9 min. Any decrease in light intensity resulted in an increase in the sleeping time but irradiances of less than 14 mW/cm2 had no measurable influence on the wake-up time. After illumination with polychromatic light from a mercury lamp the sleeping times were much shorter than after illumination with a halogen lamp at the same conditions and intensity. This difference is attributed to the relatively higher portion of U.V. light in the total emission of the Hg lamp. Effects of the spectral composition of the incident light beam on the wake-up of the sleeping hornets were also investigated. Near U.V. light in the 300-400 nm region was found to be most efficient. Shorter wavelengths as well as wavelengths between 400-470 nm had less influence and wavelengths above 470 nm had very little effect on the wake up. The sleeping times of hibernating queens were relatively longer than those of workers and drones under the same conditions. These effects are ascribed to the extraretinal light perception. The possible reasons underlying this phenomenon are discussed.  相似文献   
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The treatment of high blood pressure at the general medical clinic of a traditionally oriented university hospital was found to be unsatisfactory for most patients. Charts of all hypertensive patients (diastolic blood pressure, greater than or equal to 105 mm Hg) who made their first clinic visit in 1964 or 1971 were reviewed. Half of all patients were lost to follow-up within the first year, and blood pressure control was achieved by only one third of the patients. New information contained in the Veterans Administration study reports (1967 and 1970) had no effect on workup, compliance, or blood pressure decline. Furthermore, no significant relationship was found between blood pressure reduction and medical process, therapeutic regimens, or patient compliance. These data suggest that, in contrast to experience obtained in programs specifically designed for long-term management of this chronic disease, the present-day general medical clinic cannot satisfy the needs of most hypertensive patients.  相似文献   
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In accordance with the fundamental concept of the systems symmetrical approach, a model of the body's "ideal functional status" and a polyparametric method for diagnosing the human functional status (the method has been patented in Russia) were developed, on the basis of the unified set of amplitude and time parameters of a complex of physiological parameters (ECG, etc.). The systems symmetrical approach is basically new in defining the ratio of harmonic parameters acting as new diagnostic evidence for the health status. The unchanging ratio of parameters of autovariation processes in the cardiac, vascular, and respiratory systems, their changes in the development of the adaptative syndrome and the value were examined in healthy individuals at rest and during exercise an intensive productive activity (point brazing at a plant of electron devices), and in the trainees. It was demonstrated that the mechanism of development of adaptative processes was associated with the synchronization of autovariations in the cardiorespiratory and vascular systems and the involution of adaptative processes, their break, depletion, i.e. stress, were determined by the imbalance of relationships and the desynchronization of autovariations in these systems. To define a set of cardiorespiratory and hemodynamic parameters is necessary, but insufficient to evaluate (diagnose) the health status and health-disease intermediate diseases (stress and adaptative overtension). The ratio harmonicity of these parameters, i.e. well-balanced relations between the subsystems is the main characteristic. The assessment of the human health status in terms of the reference-the model of the ideal status as the ideal health status without using the complex and indefinite concept of the normal and moderate health status-is conceptual for polyparametric status estimation.  相似文献   
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