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981.
BL Wajchenberg A Halpern CE Leme AC Lerário AA Silveria PA Fioratti FP Cesar 《Canadian Metallurgical Quarterly》1976,25(9):957-971
A standard 4-hr ethanol infusion (236 mg/min) after a 3-day fast with and without phenformin (25 mg q.i.d.), with blood drawn every hour for 8 hr, was performed on five normal subjects, eight obese nondiabetics, seven obese chemical diabetics, and four nonobese diabetics. Control infusion induced in all subjects a decline in blood sugar levels during and/or after the alcohol challenge, with a parallel decrease in basal plasma insulin. Hypoglycemia and the decrease in insulin secretion were associated with increased plasma free fatty acid concentration. Addition of phenethylbiguanide (PBG) to the preparatory 3-day fast resulted in a greater drop in the blood glucose levels of the normal control subjects, obese and nonobese diabetics; in the obese nondiabetics, however, significantly lower degree of blood glucose decrease than control was elicited. Furthermore, obese nondiabetics altered their blood glucose-insulin interaction with apparent increased responsivess of the B cells of PBG. The results suggest that effects of phenformin on blood glucose levels are more dependent on the metabolic state of the patient than on a property of the drug itself. 相似文献
982.
AI Mitre WC Nahas W Alfer BL Wajchenbeg M Borrelli G Menezes de Goes 《Canadian Metallurgical Quarterly》1980,86(7):539-543
The authors report two cases (in brothers) of the persistence of Muller's ducts (uterus and uterine tubes), whilst both individuals led a normal though infertile sex life. They presented with a bilateral inguinal hernia and a cryptorchidism. The precise diagnosis was made at surgery in the first, whilst the family history led to the diagnosis in the second. Both underwent bilateral orchidopexy, and hysterectomy with excision of the uterine tubes. The caryotypes were normal. Of anatomical interest was the fact that both had vas deferens included within the uterine wall but the there was no continuity between the epididymes and the testes. The latter contained seminiferous ducts, Sertoli cells and spermatogonia but no spermatocyte nor spermatozoa. On the basis of these cases, the authors emphasise their demonstrative nature: the presence of testes resulted by the secretion of testosterone in the induction of normal external genitalia whilst the absence of factor inhibiting Mullers ducts (or tissue resistance to this factor) resulted in the development of the uterine tubes and uterus. 相似文献
983.
这栋傲视群雄的建筑物本身就是一座城市.有多种娱乐节目提供给好投机的游客。其内部所显现的如梦似幻的设计概念将众多的游客带进一个虚拟环境。色彩、质地、光线及暗影等设计元素营造出特定的氛围。 相似文献
984.
AE Denes JW Ebert KR Berquist BL Murphy JE Maynard 《Canadian Metallurgical Quarterly》1976,10(3):571-572
Virazole (Ribavirin, ICN 1229), a broad-spectrum, antiviral chemotherapeutic agent was used to treat two adult chronically hepatitis B surface antigen (HB(s) Ag)-seropositive chimpanzees. No significant change in serum hepatitis B surface antigen was noted and no adverse reactions were observed. The role of viral replication in the chronic carrier state of hepatitis B is discussed. 相似文献
985.
BL Duffy 《Canadian Metallurgical Quarterly》1976,50(40):1551-1552
Two patients in whom respiratory obstruction with an insidious onset occurred during the use of a Lapro endotracheal tube are described. In one patient, the valvular nature of the obstruction produced bilateral tension pneumothoraces. 相似文献
986.
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989.
KP Lesch J Gross E Franzek BL Wolozin P Riederer DL Murphy 《Canadian Metallurgical Quarterly》1995,37(4):215-223
Genetic factors have been implicated in the etiology of affective disorders but due to the complex inheritance patterns of these disorders, identification of the responsible gene(s) has so far been unsuccessful. Decreased platelet serotonin (5-HT) transport and reduced binding of imipramine or paroxetine to brain and platelet 5-HT uptake sites/transporters in patients with depression and suicide victims define the 5-HT transporter (5-HTT) as a candidate gene. The primary structure of the 5-HTT was analyzed in 17 patients meeting DSM-III-R diagnostic criteria for major depressive or bipolar disorder and in 4 healthy controls using polymerase chain reaction (PCR-) amplification and sequencing of complementary deoxyribose nucleic acid (cDNA) synthesized from platelet 5-HTT messenger ribose nucleic acid (mRNA). Direct PCR sequencing of the protein coding region failed to reveal changes in the deduced amino acid sequence of the platelet/brain 5-HTT (40,000 base pairs sequence screened), although a conservative single-base substitution representing a silent polymorphism was found. The results provide preliminary evidence that alterations in the primary structure of 5-HTT are not generally involved in the pathogenesis of unipolar depression and manic-depressive illness. 相似文献
990.
PR Ortiz de Montellano BL Mangold C Wheeler KL Kunze NO Reich 《Canadian Metallurgical Quarterly》1983,258(7):4208-4213
Oxidation of 1-octene by cytochrome P-450 results concurrently in formation of 1,2-oxidooctane and in N-alkylation by the catalytically activated olefin of the prosthetic heme group. The stereochemistry of trans-1-[1-2H]octene is retained during both transformations. This alkylation stereochemistry requires addition of the pyrrole nitrogen and the activated oxygen to the same side of the double bond, a reaction geometry opposite to that expected if the heme were alkylated by the epoxide metabolite. Stereochemical analysis shows that the S enantiomer of the epoxide is formed in slight excess over the R enantiomer by oxidation of the re and si faces, respectively, of the olefin, but that heme alkylation only occurs during oxidation of the re face. The stereochemical specificity of epoxidation and heme alkylation requires that (a) the two processes proceed by independent (probably concerted) mechanisms, or (b) the two processes diverge from a common acyclic intermediate. 相似文献