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101.
Studies on the mechanism of phorbol ester-induced inhibition of intercellular junctional communication 总被引:1,自引:0,他引:1
Intercellular gap-junctional communication was measured using[14C]citrulline incorporation in co-cultures of argininosuccinatelyase-deficient human fibroblasts and argininosuccinate synthetase-deficientChinese Hamster V79 cells. As previously shown, in this systemjunctional communication is completely inhibited by the tumorpromoting phorbol ester 12-O-tetra-decanoylphorbol-13-acetate(TPA). In the absence of extracellular calcium, TPA inhibitionwas less pronounced. However, synergism with calcium ionophoreA23187 could not be demonstrated. Chlorpromazine, trifluoperazineand 3,4,5-trimethoxybenzoic acid 8-(diethylamino)octyl esterpartially antagonised the effect of TPA. No antagonism was demonstrablebetween calmidazolium and TPA. Treatment of co-cultures withexogenous phospholipase C or 1-oleoyl-2-acetylglycerol (OAG)resulted in communication inhibition, suggesting that proteinkinase C activation is involved in the mechanism of phorbolester-mediated communication inhibition. However co-cultureswhich had been made refractory to TPA by prolonged exposureto high concentrations remained sensitive to inhibition by phospholipaseC and OAG. These results suggest either that diacylglycerolcan produce other effects independent of protein kinase C activation,or that refractoriness to phorbol esters is not simply due toa decrease in the amount of protein kinase C. 相似文献
102.
Characteristics of very poor outcome schizophrenia 总被引:2,自引:0,他引:2
R S Keefe R C Mohs M F Losonczy M Davidson J M Silverman K S Kendler T B Horvath R Nora K L Davis 《The American journal of psychiatry》1987,144(7):889-895
The authors compared 21 "Kraepelinian" schizophrenic patients who had been ill and dependent on others for the past 5 years with 76 chronic schizophrenic patients in remission or with exacerbations requiring hospitalization. The Kraepelinian patients met the criteria for schizophrenia by more diagnostic systems than the exacerbated patients, were less responsive to haloperidol, had more severe negative symptoms, and had similarly severe positive symptoms. They had cerebral ventricles that were more asymmetrical and a greater family history of schizophrenia spectrum disorders than the other chronic patients. These data suggest that patients with 5 years of illness and complete dependency on others may represent a subgroup of schizophrenia. 相似文献
103.
Androstenedione may organize or activate sex-reversed traits in female spotted hyenas. 总被引:2,自引:0,他引:2 下载免费PDF全文
S E Glickman L G Frank J M Davidson E R Smith P K Siiteri 《Proceedings of the National Academy of Sciences of the United States of America》1987,84(10):3444-3447
Spotted hyenas (Crocuta crocuta Erxleben) present a unique syndrome of reversal in behavioral and anatomical distinction between the sexes: females are heavier and more aggressive than males and dominant over them. The female's external genitalia include a false scrotum and a fully erectile pseudopenis through which mating and birth take place. Results of studies of circulating testosterone levels in wild spotted hyenas do not account for the "male-like" characteristics of the female. Androstenedione, however, is consistently higher in females than in males, particularly during early infancy. Experiments on rodents show that androstenedione can be a potent organizer of anatomical and behavioral differentiation. This study suggests that it may also produce the profound virilization of female spotted hyenas. 相似文献
104.
A rapid assay is described for the simultaneous determination of emetine and cephaeline in ipecacuanha and its preparations, based upon the different fluorescence intensities of the alkaloids at pH 1 and pH 12. The assay involves the measurement of fluorescence at 317 nm of dilutions of the sample in 0.1 M hydrochloric acid (pH 1) and 0.01 M sodium hydroxide (pH 12) with an excitation wavelength of 283 nm. Concentrations of the individual alkaloids are calculated using two simultaneous equations derived from the experimentally determined coefficients of fluorescence of solutions (1 μg/ml) of emetine and cephaeline at pH 1 and pH 12. The procedure, which has been shown to be accurate, precise and sensitive, requires only 1 ml of a liquid sample and less than 0.5 g of powdered root. There was reasonable agreement between the total concentrations of alkaloids in tinctures and liquid extracts of ipecacuanha determined by the spectrofluorimetric method and by the titrimetric procedure of the British Pharmacopoeia. The fluorimetric procedure gave higher levels of alkaloids in the powdered root than did the B.P. method; this difference is explained by incomplete extraction of the alkaloids in the B.P. procedure for powdered ipecacuanha root. 相似文献
105.
Thairu Lucy Gehling Hanna Kafwanda Sarah Yeboah-Antwi Kojo Hamer Davidson H. Lunze Karsten 《Maternal and child health journal》2022,26(6):1375-1383
Maternal and Child Health Journal - Mothers in resource-limited areas face barriers in initiating care for ill newborns, leading to delays that may contribute to newborn mortality. This qualitative... 相似文献
106.
The primary purpose of this investigation was to evaluate the relationship between milk-fat intake and obesity, particularly abdominal obesity, in 13,544 U.S. adults. A lesser objective was to measure the degree to which the association was influenced by multiple potential confounding variables. This cross-sectional study used data from the 2011–2016 National Health and Nutrition Examination Survey (NHANES). Quantity of milk-fat regularly consumed was the exposure variable. Sagittal abdominal diameter (SAD), a measure of abdominal obesity, and body mass index (BMI) were the outcome variables. Sagittal abdominal diameter is a strong predictor of visceral abdominal fat, when measured by computed tomography, and has been shown to predict cardiometabolic disorders better than BMI. After controlling for age, race, gender, physical activity, leisure computer use and gaming, alcohol habits, and cigarette use, significantly lower BMIs were associated with consistent non-fat and full-fat milk consumption (F = 4.1, p = 0.0063). A significantly lower SAD was associated only with regular consumption of non-fat milk (F = 5.0, p = 0.0019). No significant differences were detected between the other milk-fat groups or milk abstainers. In this nationally representative sample, only 19.6% of adults regularly consumed low-fat milk. In conclusion, consistent non-fat milk intake was predictive of lower levels of abdominal adiposity compared to consumption of higher levels of milk-fat. 相似文献
107.
108.
Costa Davidson Ribeiro Pessoa Diego Rodrigues Seefeldt Vanessa Borelli Costa David Ribeiro Maia Daniel Tineu Leite dos Santos Maciel Thiago Mota Brenda Barros Magalhães Delpasso Carolina Alves Ribeiro Camila Alves Delpasso Nicolau Renata Amadei 《Lasers in medical science》2021,36(8):1681-1689
Lasers in Medical Science - This study compared the effects of LED therapy associated with occlusal splint (OS) on the signs and symptoms of temporomandibular disorder (TMD). In this randomized,... 相似文献
109.
Stamborowski Sadi Fernando de Oliveira Spinelli Bruna Moreira Lima Fernanda Pupio Silva Costa Davidson Ribeiro de Silveira Souza Gabriela Aparecida Lima Mario Oliveira Lopes Martins Rodrigo Alvaro Brandão 《Lasers in medical science》2021,36(8):1741-1749
Lasers in Medical Science - Physical activity raises body temperature. However, the literature does not contain studies about whether the employment of hotobiomodulation (PMB) could significantly... 相似文献