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141.
The purpose of this study was to investigate the main differences in recent life events preceding suicide between alcoholic and depressive nonalcoholic suicide victims, how much these differences were sex- and age-dependent, and how social support varied between these groups.
Using the psychological autopsy method, retrospective best-estimate diagnoses by DSM-III-R criteria were assigned to a randomized 16.4% sample ( n = 229) of suicide victims drawn from a 1-year total nationwide suicide population ( n = 1,397) in Finland. Life events during the last 3 months (32 items) and social support (6 items) of 75 suicide victims with alcohol abuse/dependence diagnoses were compared with those of 69 nonalcoholic depressive victims.
Among male suicides, the alcoholics had experienced more separations and family discord, financial trouble, and unemployment, whereas the depressives had experienced more somatic illness. Among females, adverse interpersonal events had been common in both alcoholic and depressive victims. Among the alcoholics, unlike the depressives, the number of adverse interpersonal life events had not diminished with increasing age. Living alone had been twice as common among the alcoholic suicides and, in these cases, recent separation, unemployment, and financial trouble were remarkably common, suggesting a concurrent stressor effect.
Our results confirm and extend the earlier findings of excess interpersonal stressors among alcoholic suicides compared with depressive suicides. The findings suggest that multiple adverse life events and living alone need to be taken into account in clinical practice when assessing psychosocial stress and suicidal danger in alcoholism.  相似文献   
142.
143.
The release of radioactive histidine was studied in a superfusion system by using preloaded rat cerebral cortical slices and guinea pig synaptosomes. ATP/ADP ratios in both preparations were used to assess the energy levels and thus the oxygenation of brain slices and synaptosomes. ATP/ADP ratios similar to the intact brain and nerve terminals were found in slices and synaptosomes even after hours of superfusion with oxygenated buffer. Depolarization by 30 or 50 mM K+ induced release of histidine from slices and synaptosomes. The results confirm that under physiological energetic conditions, histidine is released both from slices and synaptosomes after depolarization with potassium.  相似文献   
144.
Divalent copper (Cu) and methyl mercury (Met-Hg) are potent inhibitors of the uptake of 5-hydroxytryptamine (5-HT) in rat hypothalamic synaptosomes in vitro. To assess the usefulness of blood platelets as a peripheral model of central serotonergic nerve endings for neurotoxicological studies, for comparison human and rabbit platelets were utilized. Cu inhibited 5-HT uptake into human platelets when platelets were separated from plasma (the IC50 0.7-0.8 microM). Plasma added with platelets abolished the toxic influence of Cu towards platelets. Met-Hg inhibited 5-HT uptake both in washed platelets (the IC50 0.2 microM) and in platelets added in plasma (the IC50s 10-15 microM). The inhibition of uptake by Met-Hg did not depend on buffer Ca and Mg. At low concentrations of Cu, the uptake tended to be more inhibited in the presence of Ca and Mg. Zn and Hg did not affect 5-HT uptake up to 100 microM. Pb inhibited it transiently (28% at 1 microM) in the presence of Ca and Mg. Met-Hg induced the release of endogenous 5-HT from rabbit platelets when they were in a suspension in Ca-free buffer, but Cu did not, even at 100 microM concentration. The results suggest firstly, that blood platelets give results comparable with brain synaptosomes regarding inhibitory effects of metals on 5-HT uptake provided plasma is decanted. Secondly, the inhibition of 5-HT uptake by Cu appears to be purely plasma membrane related but Met-Hg may, in addition, induce release of 5-HT from storage granules.  相似文献   
145.
To investigate the relationship between vitamin A status and 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) lethality, the influence of TCDD on tissue and serum vitamin A levels was determined in the most TCDD-susceptible (Long-Evans) and the most TCDD-resistant (Han/Wistar) rat strains. The TCDD LD50 values of these two strains differ by a factor of more than 300. Groups of three rats per strain were used in a dose-response study (given single ip doses of 0, 4, 40, 400, 800 or 1600 micrograms TCDD/kg body weight and killed on day 11) and in a time-course experiment (given single ip doses of 0, 4 and, in the case of Han/Wistar rats only, 1600 micrograms TCDD/kg body weight, and killed on days 4, 11, 23, 50 and 76). The strains showed similar response over the 76-day study with respect to vitamin A levels in the liver, kidneys, testicles and serum after exposure to a sublethal dose of TCDD (4 micrograms/kg body weight). In contrast, TCDD doses lethal to the Long-Evans strain only (40-1600 micrograms/kg, day 11) markedly increased kidney and serum vitamin A levels in Han/Wistar rats, while they were practically without effect in Long-Evans rats. Hepatic cytochrome P-450 concentration, and the activities of 7-ethoxyresorufin O-deethylase, ethylmorphine N-demethylase, and uridine diphosphate glucuronosyltransferase (towards p-nitrophenol) were affected by the TCDD doses in much the same manner in both strains. These findings show that the correlations between TCDD lethality and changes in vitamin A status found among species of laboratory animals do not hold for Long-Evans and Han/Wistar strains of rat.  相似文献   
146.
The present work deals with the effects of psychotropic drug therapy on the operation of psychomotor functions used in a clinical examination of suspected drunken drivers. 100 psychiatric mental, but otherwise healthy, patients were examined; the type of medication and the number of drugs used varied greatly. In 71 cases the mean degree of error in the clinical examination was higher, and, in several of these, markedly higher than the reference values obtained earlier on suspected drunken drivers when the blood contained very small amounts of alcohol or none at all. In 18 cases coarsely-divided nystagmus was registered in patients on psychotropes. This is an obvious sign of a marked side-effect of medication but was present more infrequently than in subjects with after ingestion of alcohol.The present results indicate that application of the clinical examination method, which was originally developed for and related to the examination of alcohol cases, to subjects on psychotropes is adequate, and it is possible with clinical examination to obtain valuable medicolegal information on the impairment of physiological functions. The present review of suspected dragged drivers examined in Helsinki in 1969–1972 also supports this view.This study was supported by grants from the Sigrid Jusélius-Foundation and the Finnish Foundation for Alcohol Studies, Helsinki, Finland.  相似文献   
147.
The cell aggregate phenomenon in human wound healing was studied by the Cellstic method in 496 surgical patients, aging from 5 to 70 years. Single cells and cell aggregates, called cell aggregation centers (CAC), were washed out of the Cellstic sponge by the retrograde injection technique 3–144 hr after surgery, centrifuged, and stained with May-Grünwald-Giemsa. A transient aggregation of the inflammatory cells on the first postoperative day was followed, from the second day on, by the persistent aggregation of polymorphonuclear leukocytes, mononuclear cells, and fibroblasts with cell-connecting intercellular substance. These turbulence resistant, gradually growing CACs are considered as early strength elements which, by fusing to each other and to the edges of the wound, essentially contribute to the increase of tensile strength in wound healing.  相似文献   
148.
Adult male Han/Wistar rats were treated with 1000 micrograms 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD)/kg body weight and allowed to restabilize their body weight at a lower level. Therefore, their feeding or drinking responses were determined to the following ip challenges: NaCl (1 M, 10 ml/kg body weight); 2-deoxy-D-glucose (2DG; 400 mg/kg); sodium mercaptoacetate (MA; 800 mumol/kg); 2DG + MA (200 mg/kg + 400 mumol/kg); insulin (10 U/kg). In addition, the suppressive effects of naloxone (10 mg/kg), glucose (1.36 mg/kg) and fructose (1.36 mg/kg) on feed intake stimulated by 24-hr food deprivation were examined. After the restabilization, the body weights of TCDD-treated rats followed the course of body changes in control rats. The responses to NaCl were also similar in TCDD-treated and control rats. However, marked differences were observed in all other responses studied. Pretreatment with TCDD abolished 2DG-induced feeding, attenuated the effects of insulin and naloxone, caused an aberrant decrease in feed intake following MA, and resulted in hypersensitivity to the satiating effects of glucose and fructose. These data show that exposure to a high dose of TCDD leads to notable distortions in responses to metabolic challenges in Han/Wistar rats, which are present even when they have seemingly recovered from the acute toxicity. The results also indicate that the central nervous system plays a crucial role in TCDD toxicity, and suggest hypersensitivity to peripheral satiety signals coupled with hyporesponsiveness to metabolic cues of energy deficit to be important mechanisms in the pathogenesis of the wasting syndrome.  相似文献   
149.
The release of radioactive histidine and histamine was studied in a superfusion system by using guinea pig synaptosomes which were preloaded with 3H-histidine. Depolarization by 50 mM K+ induced a simultaneous release of histidine and histamine. The stimulated release of both of these substances was diminished when calcium was removed. The calcium-dependency of histamine release, previously demonstrated in brain slices, was confirmed using synaptosomes. It was also demonstrated that potassium-induced histidine release from guinea pig synaptosomes under superfusion conditions is at least partially calcium-dependent.  相似文献   
150.
CELLSTIC is a miniature wound drain composed of a thin silicone rubber tube and a pressed rectangular stick of viscose cellulose sponge (VCS) placed inside the inner end of the tube. When moistened and placed between wound edges two sides of the sponge expand in opposite directions leaving two free channels between the remaining sides and the tube wall for the flow of wound exudate. Most cells in the exudate become attached to the sponge, where they may further invade, multiply and be transformed. The first human fibroblasts in the CELLSTIC sponge are usually seen three or four days after implantation. CELLSTIC does not disturb normal wound healing in any way even in newborn babies, as has been proved in 155 pediatric surgical patients.As well as being a testing device for human connective tissue regeneration in general, CELLSTIC may also be used to control the local effects of various medicines and radiotherapy on human wound healing.  相似文献   
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