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101.
Since 1988, four children with long-gap esophageal atresia have undergone one-stage orthotopic jejunal pedicle-graft interposition at the age of 2 to 3 months. Obtaining enough jejunal length was no problem and major early complications did not occur. In one patient stenosis of the distal anastomosis was problematic and required corrective surgery. None of the patients demonstrated jejunitis as a result of gastroesophageal reflux. With follow-up periods of 12, 27, 46, and 60 months, all patients are doing well. It is concluded that the jejunum is a better esophageal substitute than is generally appreciated.  相似文献   
102.
M Péter  J Tóth 《Orvosi hetilap》1999,140(33):1827-1831
The transjugular intrahepatic portosystemic shunt is a relatively new interventional procedure for the treatment of portal hypertension. It helps to stop the hemorrhage from varices. Decreases the risk of rebleeding and the quantity of ascites. 32 patient underwent the intervention from the May of 1995 until October of 1998. Majority of cases belong to Childs'B and C type. In the anamnesis there were 24 alcoholic cirrhosis. Shunt patency, complications and survival were analyzed. TIPS was successfully placed in 27 patients (84%). Portocaval pressure gradient decreased from 22 mmHg to 10.3 mmHg. There was no treatment related mortality. The average follow up was 14 months. In two patients the stents are patent for 36 months. Two stents became stenotic and there were nine occlusions within three years. Hepatic encephalopathy occurred in two cases. The TIPS is a safe, alternative interventional radiological therapy in the cure of portal hypertension without the mortality and morbidity of an open surgical procedure. By the use of TIPS the portosystemic gradient decrease successfully and can be ruled.  相似文献   
103.
To study the mechanism of replication of infectious bursal disease virus (IBDV), and to determine factors on the IBDV RNA which are involved in viral replication, we used cloned full-length cDNA of both the A- and B-segments to generate infectious IBDV. Infectious IBDV was rescued from plasmids that contained full-length IBDV cDNA behind a T7 promoter, by transfecting these plasmids into cells which were infected with a recombinant Fowlpox virus that expressed T7 RNA polymerase. By using the cDNA transfection system we evaluated the effect of the length of the 3' terminus of the A-segment plus strand of IBDV. Although wild-type IBDV predominantly contains four cytosines at the 3' terminus, no difference in virus yield was found when virus was rescued from cDNAs containing three to six adjacent cytosines. When the 3' terminus was shorter than three cytosines the efficiency to generate infectious IBDV from cDNA was reduced, but IBDV could still be recovered reproducibly. The rescued viruses from cDNAs containing 3'-terminal deletions appeared to have a restored 3'-terminal sequence. The missing nucleotides are probably restored by using complementary bases of a stem-loop structure as template.  相似文献   
104.
105.
The role of diadenosine polyphosphates (ApnA, where "A" denotes "adenosine" and "n" denotes the number of phosphate groups "p") as vasoconstrictors of smooth-muscle cells and as blood-pressure regulating and insulin-releasing compounds has been described. It was the aim of this study to investigate whether specific receptors for these compounds, mediating the above mentioned effects, occur in cultured vascular smooth-muscle cells (VSMC) and in endothelium cells, and whether these compounds are degraded during incubation. Saturable binding sites for diadenosine polyphosphate [3H]Ap4A with an extremely quick saturation equilibrium, even at low temperature (4 degrees C), are present in vascular smooth-muscle cells. Diadenosine polyphosphates at micromolar concentrations displaced [3H]Ap4A from binding sites; the ranking order was Ap4A > Ap3A > Ap5A approximately Ap6A. Compounds interacting with purinergic P2X receptors such as suramin, alpha,beta-methylene ATP and pyridoxalphosphate-6-azophenyl-2',4'-disulphonic acid (PPADS), albeit at high concentrations, displaced [3H]Ap4A from its binding sites. Surprisingly, at low concentrations the compounds tested increased the binding of [3H]Ap4A, which might imply the occurrence of positive receptor cooperativity or inhibition of [3H]Ap4A degradation. By use of thin-layer chromatography it was observed that [3H]Ap4A was quickly degraded (half-life approx. 12 min) in the extracellular medium to (mainly) adenosine and inosine. [3H]Ap4A and its degradation products were quickly taken up by the cells. Degradation can be inhibited by Ap6A, alpha,beta-methylene ATP or PPADS. Rather similar degradation and uptake results were also obtained when endothelium cells were used. These data indicate that specific binding sites for [3H]Ap4A are present in vascular smooth-muscle cells and that diadenosine polyphosphates at physiological concentrations displace binding. The receptors involved might be distinct diadenosine polyphosphate receptors, although the involvement of others, such as P2X receptors, is also possible. Ap4A is quickly degraded in the extracellular space and compounds that inhibit degradation result in an increase in [3H]Ap4A binding. It should be remembered that when diadenosine polyphos-phates are being investigated in physiological and pathophysiological studies of their impact on smooth-muscle cell proliferation and on vasoconstriction (blood-pressure regulation), results obtained from long-term incubations might be critical.  相似文献   
106.
To determine the distribution of hepatitis C virus (HCV) genotypes in German isolates, nucleotide sequences of the viral nonstructural 5 (NS5) genome domains were analyzed in isolates from 107 chronically HCV-infected patients. Of these 107 patients, 46 (43.0% were infected with subtype 1a and 47 (43.9%) with subtype 1 b. Six patients (5.6%) with a history of intravenous drug abuse were infected with subtype 3a. Eight patients (7.5%) who had acquired their HCV infection in Egypt carried subtype 4a. Forty-three of the 107 patients were treated with -interferon. Of these 43 patients, 16 (37.2%) were infected with subtype 1a and 27 patients (62.8%) with subtype 1b. Three patients infected with HCV-subtype 1a (18.7%) and four patients infected with subtype 1b (14.8%) showed a sustained complete response after interferon therapy. The HCV genotype 1 with its subtypes 1a and 1 b was the most common source of HCV infection in this group of patients. There was no significant difference in response to -interferon treatment of HCV infection with the subtypes 1a or 1b.  相似文献   
107.
The short term effects of a dental health educational video on adolescents' knowledge, attitude and future behaviour were assessed. Results showed a large effect on knowledge and a small effect on five attitudinal aspects. No effects were found on future behaviour.  相似文献   
108.
OBJECTIVE: To evaluate the diagnostic usefulness of magnetic resonance imaging (MRI) in the clinical diagnosis of Creutzfeldt-Jakob disease (CJD). BACKGROUND: Creutzfeldt-Jakob disease is a rare neurodegenerative disease that belongs to the group of human spongiform encephalopathies and usually affects elderly people. It is clinically characterized by rapidly progressive dementia and development of neurological symptoms, such as myoclonus or ataxia. Until now, neuroradiologic investigations have only played a minor role in establishing the clinical diagnosis of CJD, and they are often performed to exclude differential diagnoses. SETTING: A university hospital, base of the German National Creutzfeldt-Jakob Disease Surveillance Study. METHODS AND PATIENTS: In this study, MRIs from suspected cases of CJD were examined by one investigator blinded to the diagnosis. Patients were classified according to the established clinical and neuropathological criteria. RESULTS: Bilateral symmetric, high signal intensities on T2-weighted MRIs were present in the basal ganglia of 109 (67%) of 162 patients with CJD. In the control group, which consisted of non-CJD dementia patients, these abnormalities on T2-weighted MRIs were found in 4 (7%) of 58 patients. This corresponds to a high specificity in the differential diagnosis of CJD. CONCLUSION: These results indicate that MRI is a useful and valuable tool with reasonable sensitivity (67%) and high specificity (93%) and should be considered as an additional cornerstone in the clinical diagnosis of CJD.  相似文献   
109.
110.
BACKGROUND: The excess of cardiovascular disease in end-stage renal disease (ESRD) patients is unexplained, but could relate to altered intrinsic vascular wall properties, such as increased arterial stiffness, which could be mediated by hyperhomocysteinemia. We investigated potential determinants of carotid artery stiffness in ESRD patients and the effect of long-term homocysteine-lowering treatment. PATIENTS AND METHODS: Fifty-four patients on maintenance dialysis treatment were studied at baseline. Fourty-one patients completed the treatment protocol, which consisted of a 12-week treatment with folic acid 5 mg daily with or without betaine 4 g per day, and of 1 or 5 mg of folic acid thereafter for 40 weeks. Both phases were randomized. Compliance and distensibility coefficients (CC and DC) and the stiffness index (beta) of the common carotid artery were determined at baseline and after 52 weeks of treatment using a non-invasive vessel wall movement detector system. RESULTS: At baseline, plasma total homocysteine was elevated (44.1+/-33.7 micromol/l), but showed no relationship with CC, DC or beta. Age and mean arterial pressure (MAP) were the only independent determinants of CC and DC, whereas beta was associated with age only. Plasma homocysteine showed a sustained decrease after therapy (20.7+/-9.0 micromol/l at week 52). No significant changes occurred in CC (from 0.59+/-0.21 to 0.60+/-0.22 mm2/kPa; p = 0.47), in DC (from 14.9+/-6.1 to 15.3+/-6.2 10(-3)/kPa; p = 0.55), or in beta (from 10.9+/-4.7 to 11.2+/-4.4; p = 0.64). No independent determinants were detected for the change in CC, whereas the change in DC was inversely related to the change in MAP (stand. r = -0.58; p<0.0002). The decrease in MAP after therapy was significant (p = 0.003) and was related to the dialysis mode (p = 0.003) and smoking status (p = 0.02). CONCLUSION: Folic acid treatment of hyperhomocysteinemia has no major effect on carotid artery stiffness in chronic dialysis patients. The results do, however, emphasize the importance of tight blood pressure control in these patients.  相似文献   
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