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121.
122.
The weight-reducing property of molindone, a recently introduced antipsychotic drug, was tested in 9 hospitalized chronic schizophrenic patients. There was an average weight loss of 7.6 kg after 3 months on molindone; most of the loss occurred during the first month. The mechanism producing this weight loss is uncertain, but a central anorexigenic effect may be an important factor. 相似文献
123.
Glucagon was iodinated with the lactoperoxidase method at pH 10.0 in the presence of propylene glycol using a substitution of 0.3 g-atom I/mol glucagon. Under these conditions the reactivity of the iodine to tyrosine at position 13 is found to be 4-fold that of the tyrosine at position 10. The amount of diiodotyrosine was less than one-twentieth that of the monoiodotyrosine at either tyrosine residue. Relatively pure monoiodo[125I]tyrosine-13-glucagon can be separated from other iodoglucagons by means of DEAE-chromatography. Such a homogeneous preparation with a known position of the iodine makes it possible to study a specific interaction between the monoiodoglucagon and the glucagon antisera or the glucagon receptor. 相似文献
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125.
AM Elliott RJ Hayes B Halwiindi N Luo G Tembo JO Pobee PP Nunn KP McAdam 《Canadian Metallurgical Quarterly》1993,7(7):981-987
Isolated ventral and dorsal rat spinal roots incubated in normal (2.5 mM) or high glucose (25 mM) concentrations or in high concentrations of other hexoses were exposed transiently to hypoxia (30 min) in a solution of low buffering power. Compound nerve action potentials, extracellular direct current potentials, and interstitial pH were continuously recorded before, during, and after hypoxia. Ventral roots incubated in 25 mM D-glucose showed resistance to hypoxia. Dorsal roots, on the other hand, revealed electrophysiological damage by hyperglycemic hypoxia as indicated by a lack of posthypoxic recovery. In both types of spinal roots, interstitial acidification was most pronounced during hyperglycemic hypoxia. The changes in the sensitivity to hypoxia induced by high concentrations of D-glucose were imitated by high concentrations of D-mannose. In contrast, D-galactose, L-glucose, D-fructose, and L-fucose did not have such effects. Resistance to hypoxia, hypoxia-generated interstitial acidification, and hypoxia-induced electrophysiological damage were absent after pharmacological inhibition of nerve glycolysis with iodoacetate. These observations indicate 1) that enhanced anaerobic glycolysis produces resistance to hypoxia in hyperglycemic peripheral nerves and 2) that acidification may impair the function of peripheral axons when anaerobic glycolysis proceeds in a tissue with reduced buffering power. 相似文献
126.
P Reiter R Cordellier JO Ouma CB Cropp HM Savage EJ Sanders AA Marfin PM Tukei NN Agata LG Gitau BA Rapuoda DJ Gubler 《Canadian Metallurgical Quarterly》1998,59(4):650-656
OBJECTIVES: The physiology of the female sexual response and its molecular mediators remain poorly understood. Nitric oxide (NO) is synthesized in neurons and is a potent relaxor of vascular and nonvascular smooth muscle. In this study, we hypothesize that vaginal atrophy and declining sexual function during menopause may be NO dependent. Using the rat as an experimental model, we examined the expression and topologic localization of vaginal NO synthase (NOS) and the concomitant induction of apoptosis under normal and estrogen-depleted conditions. METHODS: Thirty rats were categorized into six groups on the basis of phase of the estrous cycle or estrogen status after oophorectomy. The expression and cellular localization of NOS was examined in frozen sections using specific antibodies against neuronal (N-NOS) and endothelial NOS (E-NOS). Apoptotic cells were identified in situ using the terminal transferase technique (TUNEL). Trichome staining was performed in all specimens to determine smooth muscle/collagen ratios. RESULTS: N-NOS immunoreactivity was localized to nerve fibers supplying vaginal smooth muscle, perivascular nerve plexuses, and lamina propria. E-NOS was localized to vascular endothelium and perivascular smooth muscle fibers. Both E-NOS and N-NOS expression in intact cycling animals was highest during proestrous and lowest during metestrous. After oophorectomy, levels of both N-NOS and E-NOS declined substantially compared with those of intact animals, and there was a parallel induction of apoptosis. Estrogen withdrawal also resulted in increased vaginal atrophy, intramural collagen accumulation, and perivascular wall thickening, as identified by trichome staining. Estrogen replacement resulted in a significant increase in E-NOS and N-NOS expression, as well as diminished apoptosis and vaginal atrophy. CONCLUSIONS: This cellular distribution of NOS in the rat vagina suggests that NO may modulate both vaginal blood supply and vaginal smooth musculature. Estrogen appears to play a critical role in concomitantly regulating vaginal NOS expression and apoptosis in nerves, smooth muscle, vascular endothelium, and epithelium of the rat vagina. These findings may have significant clinical implications for the pathophysiology of postmenopausal female sexual dysfunction. 相似文献
127.
JO Arrow 《Canadian Metallurgical Quarterly》1996,42(12):1651-1659
In this paper we examine the link between unemployment and health. The negative health selection hypothesis, which proposes that poor health poses an unemployment risk, is tested using data from the German Socio-Economic Panel (GSOEP). The statistical influence of health related variables on the duration of employment for a cohort of workers is estimated. Results from the Cox proportional hazards regression model show gender and nationality specific negative selection. In the event of a long or chronic illness female workers are at a higher risk of unemployment than male workers. Whereas chronic illness raises the probability of unemployment among foreign workers, there is no statistical evidence for this for German workers. The paper, thus, shows that health factors determining unemployment affect different types of workers in different ways. Consequently, results from aggregate studies may be misleading. A second result of the paper is that, irrespective of gender and nationality, there is strong evidence for lagged state dependence on previous spells of unemployment, i.e. individuals who had experienced unemployment previously were more at risk of renewed unemployment than those without such spells. These findings do not only confirm the selection hypothesis, but also illustrate how labour market risks are closely associated with attributes of social inequality and how this could result in the accumulation of risks for those who are socially or politically vulnerable in the labour market. 相似文献
128.
A Robertson FM Andreasen G Bergenholtz JO Andreasen C Munksgaard 《Canadian Metallurgical Quarterly》1998,26(5-6):409-416
OBJECTIVES: Reattachment of the avulsed enamel-dentine coronal fragment to the remaining tooth structure has become an accepted clinical alternative to a resin composite build-up for the restoration of crown fractured teeth. Since little knowledge exists as to the pulpal response to this procedure, this study was designed to observe the condition of the pulp following experimentally induced crown fracture and restoration in monkeys. METHODS: Experiments were conducted in eight young green Vervet monkeys (Cercopithecus aethiops). In all, 64 fractured incisors were investigated. Light microscopic examination of pulp tissue specimens was carried out after 3 months of observation. RESULTS: The evaluation was restricted to specimens having a fracture plane within 2 mm of the pulp and no pulpal exposure. In general, pulp tissue was well preserved irrespective of the restorative procedure. Even if the restoration or the bonded tooth fragment had been lost during the follow-up period, the pulp generally remained in good condition. Inflammatory infiltrates where seen in only a few specimens and then as clusters of mononuclear leukocytes. Hard tissue repair was frequently observed and displayed various configurations from isolated hard tissue deposits to areas of extensive hard tissue repair in the coronal portion of the pulp. Pronounced hard tissue repair and occurrence of inflammatory cell infiltrates correlated with the presence of stainable bacteria on the fractured dentine surface. CONCLUSIONS: In the absence of direct exposure, reparative dentine is a frequent feature of the pulp's response to crown fracture and restoration with composite or reattachment of the crown fragment with dentine bonding. These restorative procedures appear to ensure continued function of the underlying pulp. 相似文献
129.
RL Corwin FH Wojnicki JO Fisher SG Dimitriou HB Rice MA Young 《Canadian Metallurgical Quarterly》1998,65(3):545-553
Survival, recoverability and sublethal injury of two strains of Listeria monocytogenes, Scott A and an environmental strain KM, on exposure to sea water at 12.8 or 20.8 degrees C was determined using in situ diffusion chambers. Plate counts were used to assess recoverability and injury while 5-cyano-2,3-ditolyl tetrazolium chloride (CTC) reduction was used to determine respiratory activity. T90 values (times for 10-fold decreases in numbers of recoverable cells) on non-selective medium (trypticase soya agar with 0.6% yeast extract) at 12.8 and 20.8 degrees C were 61.7 and 69.2 h for L. monocytogenes Scott A, and 103.0 and 67.0 h for L. monocytogenes KM, respectively. On selective medium (Oxford agar), T90 values at 12.8 and 20.8 degrees C were 60.6 and 56.9 h for L. monocytogenes Scott A, and 83.0 and 65.9 h for L. monocytogenes KM, respectively. With Scott A, the percentage of sublethally injured cells at 12.8 and 20.8 degrees C was 1.7 and 17.7%, respectively, while for KM the values were 19.0 and 1.6%, respectively. The fraction of cells reducing CTC but which were not recoverable on plating progressively increased on exposure to sea water. Listeria monocytogenes KM challenged at 58 degrees C showed an apparent increase in heat resistance after exposure to sea water at 20.8 degrees C for 7 d (D58 = 2.64 min) compared with before exposure (D58 = 1.24). This increase in thermal resistance was not apparent at temperatures greater than 63 degrees C, and analysis of the best-fit regression lines fitted to the thermal data obtained from the two cell populations indicated that their thermal resistance was not significantly different (P > 0.05) over the temperature range tested (58-62 degrees C). 相似文献
130.
The junction between double-lumen endotracheal tube (DLT) and anaesthetic circuit is of crucial importance to modern anaesthesiological management in thoracic surgery. We present a connector which allows for all the essential procedures, such as clinical control of DLT position, use of fiberoptic bronchoscope (FOB) to control or correct DLT position, application of differential lung ventilation patterns or simple suction manoeuvres by easy handling, minimal interference, and avoidance of disconnection or clamping. 相似文献