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1.
Using 3,3'-diclorophenolsulfoftaleinil N-acetyl-beta-D-glucosaminide as a substrate, the apparent activation energy of beta-N-acetylhexosaminidase (Hex) was determined in samples of plasma and urine, as well as in leukocyte and platelet lysates. Incubation with papain produced an increase in this thermodynamic variable for plasma Hex (precursor forms with high molecular mass) that would be caused by the proteolytic action of papain on the Hex A isoenzyme. However, digestion with papain did not significantly modify the activation energy of Hex in leukocyte and platelet lysates (mature enzymatic forms). In 11 healthy subjects and 28 patients with different renal diseases, no statistically significant differences were found with regard to the values obtained in cellular lysates for variations in the activation energy of urinary Hex, regardless of whether they presented normoalbuminuria, microalbuminuria or macroalbuminuria. These results support the hypothesis that even in patients with proteinuria, no significant amounts of plasma Hex precursor forms are found in urine samples, and the source of the enzyme activity is the kidney itself.  相似文献   
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INTRODUCTION: Tooth movement has been studied largely with respect to the force required for tipping when pressure distribution varies along the length of the periodontal ligament. But important factors for effective canine translation include the nature and magnitude of applied stress and the patient's cell biology. The purpose of this research was to test 3 hypotheses: (1) the velocity of tooth translation (v(t)) is related to applied stress and growth status, (2) a threshold of stress accounts for the lag phase, and (3) v(t) is correlated with the ratio (AI) of 2 cytokines (IL-1beta, IL-1RA) measured in gingival crevicular fluid (GCF) and stimulated whole blood (SWB). METHODS: Continuous maxillary canine retraction stresses of 13 kPa and 4, 26, or 52 kPa were applied bilaterally in 6 growing and 4 adult subjects for 84 days. Dental models and GCF samples were collected at 1- to 14-day intervals. Cytokines were measured in GCF and SWB cell cultures. RESULTS: V(t) was positively related to stress and was higher in growing subjects (P = .001). It was also related to AI(GCF) in growers (R2= 0.56) and nongrowers (R2= 0.72). Canines moved with 52 kPa showed a lag phase, and postlag phase AI(GCF) was twice that of lag phase AI(GCF). Mean v(t) and associated AI(GCF) during the postlag phase were nearly double the values for canines moved with 13 and 26 kPa. SWB production of cytokines was dose-dependent. For growing subjects, SWB IL-1RA was correlated with v(t) (R = 0.70-0.72), and AI(SWB) and IL-1beta concentrations were correlated with AI(GCF) (R = 0.73-0.78). CONCLUSIONS: V(t) varied with growth status and stresses < or = 52 kPa; stresses of < 52 kPa showed no lag phase; and equivalent stresses yielded subject-dependent differences in v(t), which correlated with cytokines in GCF and SWB.  相似文献   
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用混合粘合剂碳糊电极测定丁螺环酮   总被引:6,自引:1,他引:5  
用混合粘合剂碳糊电极测定丁螺环酮张正奇,曾鸽鸣,刘传桂,黎艳飞(湖南大学化学化工系,长沙410082)碳糊电极无毒,制作方便,表面更新容易,应用电位范围广,在药物分析中已有应用[1~5]。我们在液体石腊中加入添加剂,组成混合粘合剂,可显著改善电极的检...  相似文献   
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健胎液对小鼠围着床期子宫内膜整合素β3表达的影响   总被引:1,自引:0,他引:1  
目的 :探讨健胎液对小鼠围着床期子宫内膜整合素 β3表达的影响。方法 :将交配成功的雌鼠随机分为正常组、模型组、中药组。于小鼠妊娠第 4天 ,中药组、模型组小鼠予米非司酮 (RU4 86 ) 0 0 8mg皮下注射 ,诱导小鼠胚胎着床障碍模型 ,自妊娠第 1天起 ,中药组小鼠用健胎液进行预防性治疗 ,其它小鼠无干预性治疗。取所有妊娠第 5天小鼠的子宫为标本 ,应用免疫组化及半定量逆转录多聚酶链式反应技术检测小鼠子宫内膜 β3原位表达及其mRNA表达水平 ,比较正常组、模型组、中药组小鼠子宫内膜 β3原位表达及其mRNA表达的差异。结果 :中药组小鼠子宫内膜腔上皮和腺上皮 β3的表达水平较模型组有明显升高 (P <0 0 5 ) ,接近正常组水平 (P >0 0 5 )。模型组表达水平最低。结论 :健胎液对小鼠围着床期子宫内膜 β3的表达有促进作用。  相似文献   
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Urinary D-glucaric acid (DGA) and the activities of gamma-glutamyl transferase (GGT) and other hepatic enzymes in serum were determined in 33 noncirrhotic male alcoholics who had continued to consume alcohol until at least 24 h prior to the taking of samples. DGA excretion was significantly greater in them than in a group of 30 healthy controls (p less than 0.001), exceeding the upper reference level in 38% of the alcoholic cases (as compared with 88% for GGT). In the alcoholic patients, there was highly significant correlation between urinary DGA and serum GGT (r = 0.613, p less than 0.001), suggesting that in both cases the increased levels are due to enzyme induction. None of the biochemical variables studied were significantly correlated with estimated daily alcohol consumption. Urinary DGA levels fell off rapidly with abstinence, and in 31 alcoholic patients who had consumed no alcohol for 5 days, there was no statistically significant correlation between DGA excretion and serum GGT (r = 0.158, p congruent to 0.4).  相似文献   
8.
CG Teo 《Oral diseases》2002,8(S2):88-90
Oral hairy leukoplakia (OHL) and Kaposi's sarcoma (KS) are commonly encountered in the HIV-infected patient. A unique feature of OHL is non-cytolytic high level of replication of Epstein–Barr virus (EBV) in the glossal epithelium. The expression of viral-encoded anti-apoptotic proteins concomitant to replicative proteins probably underlies this phenomenon. The question of whether OHL arises from activation of EBV latent in the tongue, or from superinfection by endogenous EBV shed via non-glossal sites or by exogenous EBV remains unresolved. Human herpesvirus 8 (HHV8) is now seen as necessary but not sufficient cause of KS. Expression of HHV8-encoded oncogenic proteins in endothelial cells probably explains the aberrant proliferation of these cells in KS lesions. Studies into why KS is so commonly observed at the palate in HIV-infected patients may provide important clues to its pathogenesis.  相似文献   
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Debate about the best paradigm for mental health nursing is compounded by threats from mainstreaming and genericism. In nursing education, integrated practice may have been devalued in a matrix of reductionist disciplines. The 'gendered' nature of professional knowledge may create a schismatic and self-defeating attitude in nurses. Conversely, nurses may be exhorted to adopt a 'male' paradigm in order to gain academic credibility, in which the caring dimension may be lost. Other polarities such as ideological distinctions between treatment in hospital and care in the community lead to conceptual confusion. These schisms in care are detrimental to both professionals and users. The writers argue that these tensions may be addressed in an 'androgenous' model which presents a challenge to both value systems, rejects the dominance of schismatic models, and offers the potential for a new professional integrity.  相似文献   
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