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991.
PrinceandGoldfieldfirstreportedthenon--A,non--Bpost--transfusionhepatitis(NANBH)byexclusivediagnosisin1974.Theepidemiologicda.talaterconfirmedthatthereweretwokindsofNANBH,parenterallytransmittedNANBHandenterallytransmittedNANBH.'In1989,Chooandhiscolleagues['JidentifiedhepatitisCvirus(HCV)genomiccDNAbyimmunoscreeningtheAgtllcDNAlibraryofthevirus,themajorcausativeagentofparenterallytransmittedNANBH.TheanalysisofthegenomeshowedthatHCVisamemberofflavivirusfamilywithasinglepositiv… 相似文献
992.
肉毒碱对实验性心肌损伤线粒体呼吸酶的影响 总被引:18,自引:0,他引:18
以大剂量维生素D造成心肌损伤模型,以肉毒碱作为影响因素,通过电镜细胞化学方法,观察了肉毒碱对心肌线粒体细胞色素C氧化酶和琥珀酸脱氢酶的作用。结果表明,肉毒碱具有提高线粒体呼吸酶活性及保护线粒体膜结构的应用,从而保护了呼吸链的完整性,改善了心肌氧化磷酸化功能。 相似文献
993.
Is the effect of acute hyperglycaemia on interdigestive antroduodenal motility and small-bowel transit mediated by insulin? 总被引:2,自引:0,他引:2
H. A. J. GIELKENS M. VERKIJK M. FRÖLICH C. B. H. W. LAMERS & A. A. M. MASCLEE 《European journal of clinical investigation》1997,27(8):703-710
Acute hyperglycaemia inhibits antroduodenal motility. In non-diabetic subjects this inhibitory effect may result from reactive endogenous hyperinsulinaemia. Therefore, we investigated the effects of hyperinsulinaemia during both hyperglycaemia and euglycaemia on interdigestive antroduodenal motility (perfusion manometry) and duodenocaecal transit time (DCTT; lactulose breath-H2 test). Six healthy volunteers (age 20–26 years) were studied for 240 min on three separate occasions in random order during: (a) i.v. saline (control); (b) acute hyperglycaemic hyperinsulinaemia (HG) with plasma glucose at 15 mmol L?1; and (c) euglycaemic hyperinsulinaemia (HI) with plasma insulin at 80 mU L?1 and glucose at 4–5 mmol L?1. Results: DCTT was significantly (P < 0.05) prolonged during HG (158 ± 23 min) compared with control (95 ± 25 min), whereas HI had no effect (100 ± 17 min). Mean duration of complete migrating motor complex (MMC) cycles was significantly (P < 0.05) reduced during HG (63 ± 9 min) compared with control (103 ± 15 min) and HI (105 ± 16 min), which resulted from a significantly (P < 0.05) shorter duration of phase II. Antral motility was significantly (P < 0.05) reduced during both HI (20 ± 8 contractions 240 min?1) and HG (9 ± 5) compared with control (43 ± 7). It is concluded that in healthy subjects hyperglycaemia prolongs DCTT, increases duodenal MMC cycle frequency and inhibits antral motility. Hyperinsulinaemia reduces antral motor activity but has no effect on interdigestive duodenal motility or DCTT. Thus, other factors, apart from insulin, mediate the inhibitory effect of hyperglycaemia on interdigestive intestinal motility and transit. 相似文献
994.
J. J. J. de Sonnaville M. Bouma L. P. Colly W. Devillé D. Wijkel R. J. Heine 《Diabetologia》1997,40(11):1334-1340
Summary In primary care it is difficult to treat the growing number of non-insulin-dependent diabetic (NIDDM) patients according
to (inter)national guidelines. A prospective, controlled cohort study was designed to assess the intermediate term (2 years)
effect of structured NIDDM care in general practice with and without ’diabetes service' support on glycaemic control, cardiovascular
risk factors, general well-being and treatment satisfaction. The ’diabetes service', supervised by a diabetologist, included
a patient registration system, consultation facilities of a dietitian and diabetes nurse educator, and protocolized blood
glucose lowering therapy advice which included home blood glucose monitoring and insulin therapy. In the study group (SG;
22 general practices), 350 known NIDDM patients over 40 years of age (206 women; mean age 65.3 ± SD 11.9; diabetes duration
5.9 ± 5.4 years) were followed for 2 years. The control group (CG; 6 general practices) consisted of 68 patients (28 women;
age 64.6 ± 10.3; diabetes duration 6.3 ± 6.4 years). Mean HbA1 c (reference 4.3–6.1 %) fell from 7.4 to 7.0 % in SG and rose from 7.4 to 7.6 % in CG during follow-up (p = 0.004). The percentage of patients with poor control (HbA1 c > 8.5 %) shifted from 21.4 to 11.7 % in SG, but from 23.5 to 27.9 % in CG (p = 0.008). Good control (HbA1 c < 7.0 %) was achieved in 54.3 % (SG; at entry 43.4 %) and 44.1 % (CG; at entry 54.4 %) (p = 0.013). Insulin therapy was started in 29.7 % (SG) and 8.8 % (CG) of the patients (p = 0.000) with low risk of severe hypoglycaemia (0.019/patient year). Mean levels of total and HDL-cholesterol (SG), triglycerides
(SG) and diastolic blood pressure (SG + CG) and the percentage of smokers (SG) declined significantly, but the prevalence
of these risk factors remained high. General well-being (SG) did not change during intensified therapy. Treatment satisfaction
(SG) tended to improve. Implementation of structured care, including education and therapeutic advice, results in sustained
good glycaemic control in the majority of NIDDM patients in primary care, with low risk of hypoglycaemia. Lowering cardiovascular
risk requires more than reporting results and referral to guidelines. [Diabetologia (1997) 40: 1334–1340]
Received: 5 February 1997 and in revised form: 22 May 1997 相似文献
995.
SHINICHI KAKUMU MASAHIRO TAKAYANAGI KAZUO IWATA AKIHIKO OKUMURA TOSHIYUKI AIYAMA TETSUYA ISHIKAWA MASAYUKI NADAI KENTARO YOSHIOKA 《Journal of gastroenterology and hepatology》1997,12(1):62-66
Interferon (IFN) therapy is of proven efficacy in chronic hepatitis C, but it is not universally effective and is often limited by side effects. Cyclosporine A (CsA) is a potent immunosuppressant widely used in organ transplantation. We conducted a pilot study to determine whether CsA therapy could affect aminotransferase activity and hepatitis C virus RNA levels in patients with chronic hepatitis C. Cyclosporine A was administered to 10 patients (mean age of 59 years; male: female = 9:1) who did not respond to IFN therapy previously and who had elevated serum alanine aminotransferase (ALT) values for at least 6 months. All patients were positive for HCV-RNA by RT-PCR with genotype 1b. Their mean duration of hepatitis was 15 years. Oral CsA was given for 3 months in a dose that was increased at 1 month intervals from 1.5–2.0 to 2.0–3.0 and 3.0–4.0 mg/kg per day. All patients completed the treatment schedule, although two patients developed mild non-symptomatic hypertension. Serum ALT levels gradually decreased in all but one patient. The mean percentage decrease was 59.5% at the end of therapy (from 153 ± 82 to 62 ± 48 IU/L; P < 0.02). The ALT levels fell to the normal range in five patients, although once therapy was discontinued the enzyme levels tended to return to pretreatment levels. Serum aspartate aminotransferase and g-glutamyl transpeptidase levels similarly decreased. The serum HCV-RNA titre, determined by competitive RT-PCR, did not change in any patient throughout the study period. There were no appreciable alterations in other laboratory tests, such as serum creatinine levels and lymphocyte subsets, except for an increase in serum alkaline phosphatase levels. These findings suggest that CsA, even in a relatively low dose, reduces serum aminotransferase levels without serious side effects in patients with chronic-hepatitis C, although an antiviral effect was not noted. 相似文献
996.
Feather mites are potentially an important source of allergens for pigeon and budgerigar keepers 总被引:1,自引:0,他引:1
M. J. COLLOFF† T. G. MERRETT‡ J. MERRETT† C. McSHARRY † G. BOYD§ 《Clinical and experimental allergy》1997,27(1):60-67
Background Previous studies on allergy to feathers have not adddressed whether orgatiisms living on feathers (mites. lice, moulds) are a source of allergens. Objective To investigate whether feather mites produced allergens of clinical relevance to bird keepers. Methods We examined serum IgE responses of 96 pigeon breeders to an extract of feather mites from pigeons (predominantly Diplaegidia columbae). using Western blotting, specific IgE assay using AlaSTAT EIA and RAST inhibition. Results Feather mites are a major source of soluble proteins derived from feathers, accounting for up to 10% of the total weight of the feather. Forty-three sera had a negative score (0) for anti-feather mite IgE. 27 were weakly positive (1–2) and 26 had strongly positive scores (3–4). Fewer pigeon breeders with scores ± 3 were asymptomatic than those with negative scores (12 versus 40%). more had late onset symptoms (with or without early onset symptoms; 77% versus 44%) and had IgE antibody against house dust mite (89% versus 23%). Western blotting of eight sera against the extract of Diplaegidia columbae revealed 20 IgE-binding components ranging from 22 to 200 kDa. A high diversity of components was recognized by each serum: arithmetic mean 7 (range 2 14). RAST inhibition indicated feather mites had species-specific epitopes as well as ones that cross-reacted with Dermatophagoides pteronyssinus. Conclusion Strongly-positive AlaSTAT scores to pigeon leather mite were associated with allergic symptoms of late onset in pigeon breeders. We conclude that feather mites are a major source of clinically-relevant allergens for pigeon breeders. 相似文献
997.
我国丙型和戊型肝炎人群流行病学调查及流行因素的研究 总被引:55,自引:1,他引:54
为阐明丙型和戊型肝炎在我国的流行严重度和流行规律,采用描述流行病学、血清流行病学和分子流行病学相结合的研究方法,对两型肝炎的流行特征和流行因素进行了研究。结果发现;一般人群调查近9万人丙型肝炎和戊型肝炎的流行率各为2.2%和9.7%,散 生病毒性肝炎感染比率各为2.15%和16.4%。丙型肝炎在我国主要经血传播,与血液接触密切人群中HCV感染率高达50-70%,慢性化比比例高达40-60%,目前供 相似文献
998.
M. A. Curtis 《Journal of periodontal research》1997,32(1):133-139
The production of extracellular proteolytic enzymes is a widely used strategy by human parasites including bacteria, protozoa and helminths in order to ensure survival in the colonized host. The potential benefits to the organism arise through modifications to the external environment of the cell and include the release of essential nutrients, the disablement/deregulation of the host defences and the exposure of previously shielded substrata as new sites for colonization. Damage to the host may arise through direct proteolysis of structural proteins, deregulation of the inflammatory response or the compromising of the local host defences below the threshold necessary for effective defence. In order to examine these interactions and how they may be regulated in the periodontal diseases, we are examining the properties of proteases of the oral anaerobe Porphyromonas gingivalis with specificity for arginyl peptide bonds (ArgI, ArgIA and ArgIB): a family of enzymes which has been shown to exert effects on a variety of host proteins with roles in the control of inflammation and tissue homeostasis. Analysis of the gene for ArgI (protease polyprotein for ArgI - prpRl) together with structural and immunochemical studies of these 3 interrelated forms indicates that they may be regarded as critical determinants in multiple aspects of the life cycle of the organism via both proteolysis and binding processes. Together with the highly conserved nature of the gene, the data suggest that the PrpRI of P. gingivalis is an essential colonization determinant which may play an important role in the periodontal disease process. 相似文献
999.
发色三肽底物测定血浆蛋白C活性及临床应用 总被引:2,自引:0,他引:2
建立了血浆蛋白C活性水平测定的发色三肽底物法,并对临床56例病例进行了检测。以正常人血浆蛋白C活性平均值为100%作对照,30例肝硬化病人血浆蛋白C活性平均为(61.4±27.3)%;7例慢性肾功能不全病人血浆蛋白C活性平均为(51.2±25.7)%,18例正常晚期妊娠妇女血浆蛋白C活性平均为(138.0±23.5)%。与正常对照组比较,结果差异均有显著性。在的1例血栓性血小板减少性紫癜(TTP) 相似文献
1000.