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81.
The crystal structure of CaMgGeO4 is described. CaMgGeO4, Mr = 200.9, orthorhombic, Pnam, A = 11.285(5) Å, B = 5.016(2) Å, C = 6.435(2) Å, V = 364.36 Å3, Dx = 3.664 Mg/m3.λ(MoKa = 0.71069 Å, F(000) = 384, room temperature, final R = 0.045 for 1752 observed reflections. The structure is isomorphous with CaMgSiO4 (monticellite).  相似文献   
82.
Laboratory analog studies investigated the theory that narcissism and reactance contribute to causing rape. In Study 1, narcissism correlated positively with rape-supportive beliefs and negatively with empathy for rape victims. In Study 2, narcissists reported more enjoyment than other men of film depictions that presented consensual, affectionate activity followed by rape (but not in response to either affection or rape alone). In Study 3, narcissists were more punitive than other men toward a female confederate who refused to read a sexually arousing passage aloud to them. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
83.
A screening of microorganisms producing glutaryl-7ADCA acylase, an enzyme able to hydrolyse glutaric acid selectively from glutaryl-3-deacetoxy-7-aminocephalosporanic acid (glutaryl-7ADCA), has been carried out in soil samples. Five microorganisms expressing acylase activity were isolated and classified as Bacillus cereus, Achromobacter xylosooxidans, Bacillus sp., Pseudomonas sp. and Pseudomonas paucimobilis. The screening was carried out by preparing enrichment cultures containing glutaryl-7-ADCA or cephalosporin C as the selective carbon source. Four model compounds (adipoyl-, glutamyl- and glutaryl-p-nitroanilide and glutarylcoumarin), mimicking the glutaryl-7ADCA beta-lactam moiety, were synthesized as substrates suitable for the rapid screening of the microorganisms (2500) isolated from the enrichment cultures. A total of 300 strains were active on the model substrates and only 5 displayed acylase activity on glutaryl-7ADCA. The fermentation parameters, such as pH and inducer concentration, for the optimal acylase expression and acylase specificity towards the model substrates were different for each strain.  相似文献   
84.
This summary of the practice parameters describes the assessment, differential diagnosis, and treatment of children, adolescents, and adults who present with symptoms of attention-deficit/hyperactivity disorder. The rationales for specific recommendations are based on a review of the scientific literature and clinical consensus which is contained in the complete document. Assessment includes clinical interviews with the child and parents and standardized rating scales from parent and teachers. Testing of intelligence and academic achievement is usually required. Comorbidity is common. The cornerstones of treatment are support and education of parents, appropriate school placement, and psychopharmacology. The primary medications are psychostimulants, but antidepressants and alpha-adrenergic agonists are used in special circumstances. Other treatments such as behavior modification, school consultation, family therapy, and group therapy address remaining symptoms.  相似文献   
85.
OBJECTIVE: To determine prevalence of various pheno- and genotypes of Serpulina sp in young pigs in relation to diarrhea and feed medication in Swedish pig-rearing herds. DESIGN: Isolation of spirochetes. Phenotypical and genotypical classification. SAMPLE POPULATION: Young pigs (n = 358) in 19 pigrearing herds. PROCEDURE: Serpulina isolates were classified according to a biochemical scheme based on hemolysis, indole production, hippurate hydrolysis, and alpha-galactosidase, alpha-glucosidase, and beta-glucosidase activities. The 16S rRNA sequences for 10 of the field strains and 2 type strains of Serpulina spp were aligned and compared. Minimum inhibitory concentrations of olaquindox for 9 of the strains were determined. RESULTS: Weakly beta-hemolytic intestinal spirochetes (WBHIS) were isolated from 17 of the herds and 65% of the samples. More than 1 phenotype of WBHIS was found in 12 of the 19 herds. S hyodysenteriae was not isolated in any of the herds. Hippurate-positive WBHIS were isolated in 6 of 7 herds affected by diarrhea, but in only 1 of 8 herds without diarrhea. Hippurate-positive strains were closely related to the pathogenic strain P43 if judged from sequence comparisons. Strains with the same biochemical profile isolated within a herd had identical sequences, but when isolated from different herds, sequence differences were observed. The prevalence of WBHIS was reduced in herds medicated with olaquindox. Investigated field strains had minimum inhibitory concentration values < or = 1 microgram/ml for olaquindox. CONCLUSION: The presence of WBHIS, with the ability to hydrolyze hippurate, was related to diarrhea in pig herds. CLINICAL RELEVANCE: Potentially pathogenic WBHIS can be distinguished from nonpathogenic strains by the hippurate hydrolysis test.  相似文献   
86.
Recent data have suggested the existence of at least two major classes of calcitonin gene-related peptide (CGRP) receptors in brain and peripheral tissues [Henke et al., Brain Res., 410 (1987) 404-408; Dennis et al., J. Pharmacol. Exp. Ther., 251 (1989) 718-725; ibid, 254 (1990) 123-128; Quirion et al., Ann. NY Acad. Sci., 657 (1992) 88-105]. However, little is currently known in the structure characteristics of CGRP receptors as cloning as yet to be reported. In the present study, the sensitivity of [125I]humanCGRP alpha binding to guanine nucleotides and temperature was investigated in guinea pig atria (prototypical CGRP1 tissue) guinea pig vas deferens (prototypical CGRP2 tissue) and in the rat brain and cerebellum (mixed assay). Binding isotherms of [125I]hCGRP alpha in those four tissue preparations were curvilinear and best fitted to a two-site model under most assay conditions. The high affinity binding component was highly temperature-sensitive and accounted, under experimental conditions, for up to 18% of the total population of receptors. Moreover, these high affinity sites were also highly sensitive to guanine nucleotides (Gpp(NH)p, 100 microM) in all preparations although to a different extend depending upon assay temperatures. Taken together, this suggests that the different CGRP receptor subtypes present in these tissue all belong to a G-protein coupled receptor family.  相似文献   
87.
The pyrolytic behavior of inulin, a (2-->1)-linked fructofuranan, is described. Parallel investigations of the pyrolysis of glucose and of fructose were conducted to supplement the inulin results and to aid comparison with previous results from glucans. Effects of neutral and basic additives are emphasized. As with glucans, the addition of such additives (especially basic) increases the yields of the one-, two-, and three-carbon products (as well as of hexosaccharinolactones), while generally decreasing the yields of anhydro sugar and furan derivatives. The former products include glycolaldehyde, acetol, dihydroxy-acetone, acetic acid, formic acid, and lactic acid. Mechanistic speculations are made regarding the origins of these compounds, as well as of furan derivatives and saccharinic acid lactones. Parallels with alkaline degradation are considered.  相似文献   
88.
89.
Patients with unstable angina, refractory to intensive medical therapy, are at high risk for developing thrombotic complications, such as recurrent ischemia, myocardial infarction and coronary occlusion during coronary angioplasty. As both platelet aggregation and/or thrombus formation play an important role in this ongoing ischemic process, a monoclonal platelet GPIIb/IIIa receptor antibody (c7E3) or thrombolytic therapy (alteplase) might be able to modify the clinical course and underlying coronary lesion morphology. To evaluate whether alteplase or c7E3 could influence the incidence of complications, we randomized 36 and 60 patients, respectively to alteplase or placebo, or c7E3 or placebo. All patients exhibited dynamic ECG changes and recurrent pain attacks, despite maximal tolerated medical therapy. Patients were randomized in both studies after initial angiography had demonstrated a culprit lesion amenable for angioplasty. After study drug infusion quantitative angiography was repeated and angioplasty performed. Recurrent ischemia during study drug infusion occurred in 5, 6, 9 and 16 patients from the alteplase, placebo, c7E3 and placebo group, respectively. Major events defined as death, myocardial infarction or urgent intervention occurred in 7, 3, 1 and 7 patients, respectively. Two patients died: one in the alteplase group and one in the placebo group from the c7E3 study. The first patient due to retroperitoneal hemorrhage, the second as a result of recurrent infarction. Qualitative angiography showed resolution of clots in the c7E3 group only, while the same group of patients showed in 20% an improvement in TIMI flow grade, without deterioration in any patient from this group.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
90.
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