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1.
朱宝亭  褚云鸿 《药学学报》1990,25(7):490-493
本文观察了[D-Ala6,Pro9-Ethylamide10]-LHRH(LHRH-A)对孕中期大鼠的抗妊娠作用。结果显示:在孕9~11d sc 200μg/d LHRH-A,血浆孕酮水平自第二次给药后明显下降(P<0.05),给药大鼠均流产终止妊娠;LHRH-A的抗妊娠作用可被醋酸甲地孕酮所拮抗;LHRH-A对体外培养的假孕大鼠和孕d 9大鼠黄体细胞分泌孕酮有明显的直接抑制作用。  相似文献   
2.
The aim of this study was to investigate markers of serotonin and immune function in suicidal patients. Cytotoxic activity of natural killer cells (NK) and CD16 lymphocytes were studied in 28 suicide attempters and 26 healthy controls, and related in patients to 5-hydroxyindoleacetic acid (5-HIAA) in cerebrospinal fluid (CSF). Patients with CSF 5-HIAA below the median had significantly lower NK cell activity than other patients. CD16 cell frequency was significantly lower in patients than in controls, and patients also tended to have lower NK cell cytotoxicity than healthy controls. There were no statistically significant correlations between 4-hydroxy-3methoxyphenyl glycol (HMPG), homovanillic acid (HVA), CSF cortisol and NK cell activity. The results support the hypothesis of compromised immune function in suicidal patients with evidence of disordered serotonin function.  相似文献   
3.
OBJECTIVES: The purpose of this study was to examine, through the database of the Department of Veterans Affairs, the joint occurrence of different diseases in individual patients. METHODS: Patients with a diagnosis of gastric cancer, gastric ulcer, or duodenal ulcer were extracted from the 1987 through 1990 computer files. A random sample of patients from each annual file served as a control population. All previous discharges of each case or control patient between 1970 and 1990 were searched for the occurrence of hypertensive diseases or chronic diseases of the joints, lungs, pancreas, and liver. The relative frequencies of such diagnoses in case and control patients were compared by multivariate logistic regression. RESULTS: Gastric ulcer and duodenal ulcer, but not gastric cancer, were significantly associated with chronic diseases of the joints, lungs, pancreas, and liver. None of the three diagnoses showed any significant association with hypertensive diseases. CONCLUSIONS: These relationships may reflect the influence of nonsteroidal anti-inflammatory drugs, smoking, and alcohol. They stress the importance of environmental risk factors other than Helicobacter pylori in terms of damage to the upper gastrointestinal mucosa.  相似文献   
4.
Forty suicide-attempt patients who were consecutively admitted to an intensive-care unit, their significant others and treatment personnel were investigated by semistructured interviews. The patients were divided into neurosis (n = 14), abuse (n = 19) and psychosis (n = 7) groups. Twenty-one of the patients (52%) had lost contact with one or both parents before the age of 18, in 25% of cases owing to death and in 27% because of the parents' divorce or separation. Parents and/or siblings of 19 patients (47%) had shown suicidal behaviour in the form of attempted suicide and/or suicide. Differences between the groups were not significant. Alcohol abuse in the parental home was overrepresented in the abuse group compared with the other groups. The role of identification with the dead and suicidal parent in prompting suicidal actions in adulthood is discussed, as well as that of the impeded evolution of stable external object relations owing to parental losses.  相似文献   
5.
A total of 88 interviews were conducted with 40 people attempting suicide who were receiving care in an intensive-care unit, and 129 interviews were carried out with their relatives and friends. The subjects were divided into 3 diagnostic groups: neurosis (n = 14), abuse (n = 19) and psychosis (n = 7). The incidence of relatives' failure to provide care after the suicide attempt--turning-away reactions as well as do not resuscitate orders, a form of passive euthanasia--was investigated. In 8 cases, partners of patients in the abuse and neurosis groups showed turning-away reactions. In 2 cases, relatives of elderly patients in the neurosis group said to the doctor that life-preserving measures should not be taken. Relatives explained their behaviour by saying that they had the best interests of the suicidal individual at heart. In-depth interviews, however, revealed that these reactions were a manifestation of the relatives own psychic conflicts, brought forth by the confrontation with the depressed and suicidal patient. Turning-away reactions and do not resuscitate orders might be interpreted as expressing the relatives' aggressiveness towards the suicidal individual and attempts to escape from a difficult situation. It is important that doctors stand up for the interests of suicidal people, which at times may conflict with relatives' interests, and help the relatives to sort out their problems and wishes with respect to the problem areas of passive euthanasia.  相似文献   
6.
For a prospective study of lead exposure and early development, we recruited pregnant women from a lead smelter town and from an unexposed town in Yugoslavia and followed their children through 7 years of age. In this paper we consider associations between lifetime lead exposure, estimated by the area under the blood lead (BPb) versus time curve (AUC7), and intelligence, with particular concern for identifying lead's behavioral signature. The Wechsler Intelligence Scales for Children-Version III (WISC-III) was administered to 309 7-year-old children, 261 of whom had complete data on intelligence, blood lead, and relevant sociodemographic covariates (i.e., Home Observation for the Measurement of the Environment (HOME), birth weight, gender, sibship size, and maternal age, ethnicity, intelligence, and education). These showed anticipated associations with 7-year intelligence, explaining 41-4% of the variance in Full Scale, Performance, and Verbal IQ. Before covariate adjustment, AUC7 was unrelated to intelligence; after adjustment, AUC7 explained a significant 2.8%-4.2% of the variance in IQ. After adjustment, a change in lifetime BPb from 10 to 30 micro/dl related to an estimated decrease of 4.3 Full Scale IQ points; estimated decreases for Verbal and Performance IQ were 3.4 and 4.5 points, respectively. AUC7 was significantly and negatively related to three WISC-III factor scores: Freedom from Distractibility, Perceptual Organization, and Verbal Comprehension; the association with Perceptual Organization was the strongest. Consistent with previous studies, the IQ/lead association is small relative to more powerful social factors. Findings offer support for lead's behavioral signature; perceptual-motor skills are significantly more sensitive to lead exposure than are the language-related aspects of intelligence.  相似文献   
7.
We describe a patient with bilateral ureteral pseudodiverticulosis of 10 years’ duration before developing transitional carcinoma of the pelvis.  相似文献   
8.
Previous studies have suggested that, for the same power output, arm exercise requires higher oxygen uptake (VO2), carbon dioxide output (VCO2), and ventilation (VE) than leg exercise and that response kinetics are slower. To evaluate these differences, four healthy subjects performed a total of 95 arm cranking tests. Each subject performed several tests at each of three or four power outputs spaced evenly below the maximum the subject could sustain (average = 53 W). Breath-by-breath responses to identical stimuli were averaged. End-exercise blood lactate was determined at each power output. Responses were compared to leg exercise responses in these subjects (J. Appl. Physiol. 67:547-555, 1989). For power outputs unassociated with lactic acidosis, differences between steady-state VO2, VCO2, and VE responses for arm and leg exercise were not significant. At higher power outputs, the higher VO2, VCO2, and VE during arm exercise were well correlated with higher lactate. For power outputs not engendering lactic acidosis, the time constants (tau) for VO2, VCO2 and VE were not greatly different for arm than for leg exercise. For each variable, at higher power outputs tau became longer by an amount correlated with higher lactate level. Like leg exercise, the slower kinetics of VO2 and VE (but not VCO2) at higher power outputs were well described as a superimposed slower component. We conclude that both dynamic and steady-state responses of VE and gas exchange to arm exercise do not differ substantially from those to leg exercise so long as the power output does not elevate blood lactate.  相似文献   
9.
The beta-amyloid (Abeta) precursor protein (APP) is cleaved sequentially by beta-site of APP-cleaving enzyme (BACE) and gamma-secretase to release the Abeta peptides that accumulate in plaques in Alzheimer's disease (AD). GGA1, a member of the Golgi-localized gamma-ear-containing ARF-binding (GGA) protein family, interacts with BACE and influences its subcellular distribution. We now report that overexpression of GGA1 in cells increased the APP C-terminal fragment resulting from beta-cleavage but surprisingly reduced Abeta. GGA1 confined APP to the Golgi, in which fluorescence resonance energy transfer analyses suggest that the proteins come into close proximity. GGA1 blunted only APP but not notch intracellular domain release. These results suggest that GGA1 prevented APP beta-cleavage products from becoming substrates for gamma-secretase. Direct binding of GGA1 to BACE was not required for these effects, but the integrity of the GAT (GGA1 and TOM) domain of GGA1 was. GGA1 may act as a specific spatial switch influencing APP trafficking and processing, so that APP-GGA1 interactions may have pathophysiological relevance in AD.  相似文献   
10.
A significant decline (34.5%) in the suicide rate occurred in 1984–1988 throughout the USSR. The decline was observed shortly after the introduction of strict restrictions on the sale of alcohol. We tested the hypothesis that the restrictive alcohol policy in the first years of perestroika (June 1985) caused the fall in suicide rates in the former USSR. Data on alcohol consumption, violent death caused by external injury and poisoning (n= 916,315), death due to accidental alcohol poisoning (n= 77,837), suicide (n= 192,305) and death undetermined whether accidentally or purposely (n= 54,253) were analyzed for all former Soviet republics for 1984, 1986, 1988 and 1990. Men were chosen for the analysis, since men are more prone to abuse alcohol than women. Regression analysis with alcohol consumption as the independent variable and suicide rates and violent death rates as dependent variables shows that suicide and alcohol consumption were positively correlated as were violent death and alcohol consumption. In the republics with high alcohol consumption (Slavic and Baltic), suicide rates were also high. In the Caucasian republics, low alcohol consumption was associated with low suicide rates. For most republics, alcohol seems to explain more than 50% of suicides. Alcohol also has considerable explanatory value for violent death. Thus, a restrictive alcohol policy might be a way to reduce suicide and violent death.  相似文献   
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