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An experimental study of saphenous flaps in 26 dogs is reported, which confirmed the work of Baek et al. (1985) that venous flaps can survive. In addition, it showed that venous island flaps could survive after division of the venous pedicle proximally or distally, or as free flaps, providing through flow was re-established by venous anastomoses. In this study no flaps survived on a single venous pedicle without through flow. Two successful clinical cases of venous flaps are also reported, in which through flow was re-established by a simple venous anastomosis. One of these flaps threatened to become necrotic until the thrombosed anastomosis was successfully redone.  相似文献   
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In a retrospective study we analyse two populations of aged patients in congestive heart failure, one treated with ACE inhibitors other not and the other with conventional therapy. Both populations received the same medication (diuretics and digitalis) and are equivalent in age, sex distribution, NYHA functional class and echocardiographic left ventricular parameters. Comparing the mortality of the two populations at the first, second and third year of follow-up, a statistically significant reduction in mortality was found on the ACE inhibitors treated population, at the first year. However, this reduction did not reach statistical significance at second and third years. The results are similar to trials in which the effects of ACE inhibitors are studied on general populations in heart failure.  相似文献   
25.
S P Arneri?  D J Reis 《Brain research》1986,374(1):153-161
The effects of somatostatin (SOM) and cholecystokinin octapeptide (CCK-8) on basal and potassium-induced release of acetylcholine (ACh) were investigated in slices of rat caudate nucleus (CN) and, for comparison, cerebral cortex (CX). Potassium (5-55 mM) produced a concentration-dependent increase in the release of [3H]ACh in the presence of extracellular Ca2+. SOM (1 microM), CCK-8 (1 microM) and the dopamine (DA) receptor agonist, apomorphine (APO, 30 microM) inhibited the K+-induced (35 mM) release of [3H]ACh by 26-32% from CN, but did not affect ACh release from CX. Other peptides (1 microM), such as Met-enkephalin, vasoactive intestinal peptide, thyrotropin-releasing hormone and substance P, had no effect on release of [3H]ACh in CN or CX. Sulpiride (SULP), a dopamine receptor antagonist, prevented the effects of APO and SOM, but not CCK-8, to inhibit [3H]ACh release. The results indicate that: (1) SOM and CCK-8 inhibit the release of [3H]ACh in CN, but not CX; and (2) the inhibitory effect of SOM, but not CCK-8, on [3H]ACh release is mediated by dopaminergic mechanisms.  相似文献   
26.
Recent serologic, immunoprotection, and pathogenesis studies identified the Lig proteins as key virulence determinants in interactions of leptospiral pathogens with the mammalian host. We examined the sequence variation and recombination patterns of ligA, ligB, and ligC among 10 pathogenic strains from five Leptospira species. All strains were found to have intact ligB genes and genetic drift accounting for most of the ligB genetic diversity observed. The ligA gene was found exclusively in L. interrogans and L. kirschneri strains, and was created from ligB by a two-step partial gene duplication process. The aminoterminal domain of LigB and the LigA paralog were essentially identical (98.5 ± 0.8% mean identity) in strains with both genes. Like ligB, ligC gene variation also followed phylogenetic patterns, suggesting an early gene duplication event. However, ligC is a pseudogene in several strains, suggesting that LigC is not essential for virulence. Two ligB genes and one ligC gene had mosaic compositions and evidence for recombination events between related Leptospira species was also found for some ligA genes. In conclusion, the results presented here indicate that Lig diversity has important ramifications for the selection of Lig polypeptides for use in diagnosis and as vaccine candidates. This sequence information will aid the identification of highly conserved regions within the Lig proteins and improve upon the performance characteristics of the Lig proteins in diagnostic assays and in subunit vaccine formulations with the potential to confer heterologous protection.  相似文献   
27.
Thirty persons with Class II Division 1 subdivision malocclusions, ranging in age from 12 years 8 months to 42 years, underwent computed tomography of the temporomandibular joints. The images obtained from sagittal slices were used to assess the depth of the mandibular fossa, the angulation of the posterior wall of the articular tubercle, the condyle-fossa relationship, and the concentric position of the condyles associated with this malocclusion. Paired Student t tests were applied, and Pearson product moment correlations (r) were determined after measurements on both Class I and Class II sides were obtained. No statistically significant asymmetries were found in the depth of the mandibular fossa, the angulation of the posterior wall of the articular tubercle, or the condyle-fossa relationship. However, a statistically significant (P <.05) anterior positioning of the condyles was observed.  相似文献   
28.
Fiala  ES; Sohn  OS; Li  H; El-Bayoumy  K; Sodum  RS 《Carcinogenesis》1997,18(9):1809-1815
We observed that pretreatment of male F344 rats with benzyl selenocyanate, a versatile organoselenium chemopreventive agent in several animal model systems, decreases the levels of DNA and RNA modifications produced in the liver by the hepatocarcinogen 2- nitropropane. To clarify the mechanisms involved, we pretreated male F344 rats with either benzyl selenocyanate, its sulfur analog benzyl thiocyanate, phenobarbital or cobalt protoporphyrin IX; the latter is a depletor of P450. We then determined (1) the ability of liver microsomes to denitrify 2-nitropropane, (2) effects on 2-nitropropane- induced liver DNA and RNA modifications and (3) amount of nitrate excreted in rat urine following administration of the carcinogen. Pretreatment with benzyl selenocyanate or phenobarbital increased the denitrification activity of liver microsomes by 217 and 765%, respectively, increased liver P4502B1 by 31- and 435-fold, respectively, decreased the levels of 2-nitropropane-induced modifications in liver DNA (29-70% and 17-30%, respectively) and RNA (67-85% and 30-50%, respectively), and increased the 24-h urinary excretion of nitrate by 157 and 209%, respectively. Pretreatment with benzyl thiocyanate had no significant effect on any of these parameters. Pretreatment with cobalt protoporphyrin IX decreased liver P4502B 1 by 87%, decreased the denitrification activity of liver microsomes by 76%, decreased the 24 h urinary excretion of nitrate by 88.5%, but increased the extent of 2-nitropropane-induced liver nucleic acid modifications by 17-67%. These results indicate that the metabolic sequence from 2-nitropropane to the reactive species causing DNA and RNA modifications does not involve the removal of the nitro group. Moreover, they suggest that benzyl selenocyanate inhibits 2-NP-induced liver nucleic acid modifications in part by increasing its detoxication through induction of denitrification, although it is evident that other mechanisms must also be involved.   相似文献   
29.
The purpose of the present study was to determine whether lesions of areas projected to by the central amygdaloid nucleus (ACE) would disrupt the classical conditioning of autonomic and/or behavioral emotional responses. The areas studied included 3 projection targets of the ACE: the lateral hypothalamic area (LH), midbrain central gray (CG) region, and bed nucleus of the stria terminalis (BNST). Lesions were made either electrolytically or by microinjection of ibotenic acid, which destroys local neurons without interrupting fibers of passage. Two weeks later, the animals were classically conditioned by pairing an acoustic stimulus with footshock. The next day, conditioned changes in autonomic activity (increases in arterial pressure) and emotional behavior ("freezing," or the arrest of somatomotor activity) evoked by the acoustic conditioned stimulus (CS) were measured during extinction trials. Electrolytic and ibotenic acid lesions of the LH interfered with the conditioned arterial pressure response, but did not affect conditioned freezing. Electrolytic lesions of the rostral CG disrupted conditioned freezing but not conditioned changes in arterial pressure. Ibotenic acid injected into the rostral CG reduced neither the arterial pressure nor the freezing response. Injection of ibotenic acid in the caudal CG, like electrolytic lesions of the rostral CG, disrupted the freezing, but not the arterial pressure response. Injection of ibotenic acid into the BNST had no effect on either response. These data demonstrate that neurons in the LH are involved in the autonomic, but not the behavioral, conditioned response pathway, whereas neurons in the caudal CG are involved in the behavioral, but not the autonomic, pathway. Different efferent projections of the central amygdala thus appear to mediate the behavioral and autonomic concomitants of conditioned fear.  相似文献   
30.
Recent studies have demonstrated that α-Smooth Muscle actin expression in glomerular and tubulointerstitial compartments of renal tissue could represent a prognostic marker in several renal diseases. Our objective was to identify the prognostic value of α-SM actin actin expression on the evolution of renal damage in Primary IgA nephropathy (Berger’s Disease). 43 patients followed up from 1988 to 1999 at the University Hospital, Faculty of Medicine of Ribeirão Preto, University of São Paulo, Brazil, was studied. Clinical-laboratory data were obtained from the medical records of the patients using a protocol containing name, race, gender, origin, profession, age at clinical presentation of the disease and personal and family history. The parameters assessed in the approach to IgA nephropathy were serum creatinine, creatinine clearance, serum albumin, total serum protein, 24 hours proteinuria, glycaemia, serum sodium, potassium, calcium and phosphorus ions, analysis of urinary sediment, serum complement profile, blood count, and renal biopsy. Morphological evaluation was performed by renal biopsy using common light and immunofluorescence microscopy. Immunohistochemical studies were performed using a murine monoclonal antibody to α-SM actin. Our data showed that α-SM actin expression in the glomerular and tubulointerstitial compartments are not correlated with unfavorable clinical course of primary IgA nephropathy.  相似文献   
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