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81.
The human mineralocorticoid receptor of the steroid receptor family contains a modular structure with domain E which is considered to be a hormone binding domain. Recombinant protein approaches enabled us to clearly determine that this domain is also able to interact with F-actin (Kd about 2 microM) and G-actin. Moreover, it was revealed that this mineralocorticoid receptor domain/actin interaction was modulated by specific mineralocorticoid ligands. Agonist (aldosterone) steroid binding almost totally (91%) abolished the interaction with F-actin, while antagonist (progesterone) binding allowed more than 30% of this binding. Steroid modulation of the interaction between domain E and actin indicated that this actin binding is specific and could be essential for cellular mineralocorticoid receptor activity.  相似文献   
82.
Family structure and function and their association with knowledge and attitudes toward sexuality, contraception, and sexually transmitted diseases (STD) were studied in 918 students and 312 adolescents working in factories. Unmarried workers reported higher rates of sexual activity than did students (30.9% vs. 21.8%, p = .04 for males; 12.9% vs. 6.0%, p = .005 for females). Among sexually active males, 33.3% of students and 30.7% of workers used contraception, compared with 27.5% of female students and 9.5% of female workers. Workers were from larger families than students, and the male and female workers had lower scores for knowledge on sexuality, contraception, and STD than did students. Multiple stepwise regression showed that age and schooling of the parents were associated with knowledge and attitudes in the students. In workers, the position of the child in the family was a negative regressor for attitudes and knowledge on sexuality in males, and for knowledge on contraception and STD in females. In regard to family function, the significant factors were compromise between the parents, positive affective response, communication within the family, problem solution, and control of behavior. It was concluded that female workers are at higher risk for unwanted pregnancies and STD. The factors associated with knowledge and attitudes were age, schooling of the parents, mother working out of home, position of the adolescent in the family, and the diverse aspects of family function.  相似文献   
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This paper reviews the pathogenesis of Mycobacterium bovis infection in cattle, focusing on aspects relating to the host rather than the organism. A broad concept of pathogenesis has been considered and information is presented on sources and routes of infection, as well as the immune responses and pathology. In addition, data is presented on the excretion of M. bovis from tuberculous cattle.  相似文献   
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OBJECTIVES: Identify factors predicting favorable outcome after medical management of valve ring abscesses in order to propose a surveillance schedule for conservative treatment. METHODS: A multicentric study conducted from July 1989 to February 1996 included 28 patients (mean age 64 +/- 16 years, range 26-83) hospitalized for active endocarditis and valve ring abscesses diagnosed at transthoracic or transesophageal echography. Conservative medical therapy was given because of a decision of the medico-surgical team (n = 9), high surgical risk (n = 12), or patient refusal of surgery (n = 7). Outcome was favourable in 18 patients (Group I) and unfavorable in 10 (Group II) due to death (n = 9) or subsequent surgery (n = 1). Univariate and multivariate analysis were used to determine differences between the groups in terms of clinical and laboratory data. RESULTS: Mean follow-up in Group I was 33 +/- 18 months and 15 +/- 10 months in Group II. Univariate analysis showed significant differences between Group I and II respectively for age (59 +/- 18 yr vs 72 +/- 10, p = 0.04), delay to apyrexia after antibiotics (4.3 +/- 2.8 vs 8.3 +/- 2.4 days, p < 0.0008), heart failure (5% vs 70%, p = 0.003), grade III or IV valvular regurgitation (5% vs 60%, p < 0.04), and mean surface area of the abscess (1.5 +/- 1.2 vs 5.4 +/- 6.4 cm2, p < 0.03). Independent factors at multivariate analysis were by decreasing order: lack of heart failure at admission, delay to apyrexia, abscess surface area, and age. Outcome was favorable (mean follow-up 33 +/- 10 months) in all patients with an abscess surface area < 1.5 cm2, no signs of heart failure, no grade III or IV valvular regurgitation, apyrexia after less than 8 days on antibiotics and no staphylococcus positive blood culture. CONCLUSION: Medical management of valve ring abscesses may be indicated in selected patients in care units with rigorous surveillance facilities. Further studies are needed to precisely identify surveillance and treatment criteria.  相似文献   
88.
The aqueous solution structure of the cyclic pentapeptide cyclo(-Ser-D-Leu-Asp-Val-Pro-) has been determined by two-dimensional 1H-NMR spectroscopy, combined with a conformational search and distance-geometry calculations. As many as five conformers in slow exchange were observed, and the rate of interconversion between components was measured from the build-up rates of exchange peaks. NMR data allowed the structures of the two predominant conformers to be determined. The major component (66%) contained a cis-proline as part of a type-VIa2 beta-turn encompassing residues Asp-Val-cis-Pro-Ser. The second component (16%) contained only trans-amide bonds, and a type-VIII beta-turn formed by residues Val-Pro-Ser-D-Leu. These structures are discussed in relation to the (phi, psi), space available to the cyclic pentapeptide, determined by a conformational search, and in relation to previously published cyclic-pentapeptide structures. The molecule exhibits activity in a scintillation-proximity assay for the inhibition of the interaction between the integrin very-late antigen-4 (VLA-4; alpha 4 beta 1) and vascular-cell-adhesion molecule-1 (VCAM-1). The structure/activity relationship of the LDV sequence is discussed and related to the recently published X-ray structure of VCAM-1. The relevance of the work to the design of anti-inflammatory drugs is discussed.  相似文献   
89.
Earlier studies have established that mutant strains of Azotobacter vinelandii that do not synthesize ferredoxin I (AvFdI) overexpress another protein designated Protein X (Morgan, T. V., Lundell, P. J., and Burgess, B. K. (1988) J. Biol. Chem. 263, 1370-1375). This protein has now been purified using two-dimensional gel electrophoresis as an assay. The purified protein is a monomer with M(r) approximately 29,000 which degrades slowly to a specific M(r) approximately 22,000 form when stored in solution. The native protein is bright yellow and contains noncovalently attached FAD that is reduced by either dithionite or NADPH without formation of a stable semiquinone. Titration with NADP+/NADPH gives an E0' value of approximately -327 mV versus SHE. Because this E0' is so close to that of the NADP+/NADPH couple it is not clear if Protein X is an NADPH oxidase or an NADP+ reductase in vivo. Comparison of the NH2-terminal sequence and other properties of Protein X with those of other proteins, suggests that it is likely to be related to the Escherichia coli ferredoxin NADP+ reductase (the fpr gene product), and affinity chromatography shows that Protein X binds specifically to AvFdI.  相似文献   
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