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71.
Abstract Titrations of anti-hepatitis C core (anti-HCc) immunoglobulin G (IgG) antibodies and its subclasses were studied in 90 patients with acute and chronic hepatitis C virus (HCV) infection, including 27 patients who underwent interferon (IFN) therapy. The positivity rates for each anti-HCc subclass were as follows: 95.2% for IgG1, 12.0% for IgG2, 69.9% for IgG3 and 19.3% for IgG4. The total anti-HCc IgG titre correlated well with the IgG1 titre, indicating that IgG1 was the main virus-specific IgG. Changes of IgG1 production mainly contributed to fluctuations of the anti-HCc IgG titre and corresponded well to positivity for HCV-RNA during and after IFN therapy. IgG3 was detected prior to IgG1 during the early phase of acute hepatitis in some cases and also appeared with relapse after IFN therapy. The serial assay of anti-HCc subclasses showed the patients' humoral immune response to HCV infection, and might be useful for evaluation of anti-viral immunity influenced by IFN therapy.  相似文献   
72.
A case of concurrent pityriasis rotunda and acquired ichthyosis associated with IgG-myeloma is described.  相似文献   
73.
A 36-year-old man presented with macroscopic hematuria associated with right flank pain. Examination of the patient revealed a cystic mass in the right kidney. Because the mass had increased in size, enucleation of the mass was performed. Histopathological findings revealed nephroblastoma, therefore, radical nephrectomy was performed. We believe the pathogenesis of the cystic formation to be a process in which a tumor that had developed in the pericalyceal region spontaneously ruptured, exuding urine into the perinephric space, forming a cystic mass. The patient is alive with no evidence of disease 24 months after the operation.  相似文献   
74.
Recent developments in pacemaker technology led us to report our initial and follow-up assessment of atrioventricular (A-V) sequential systems in 50 consecutive patients. Primary indications for pacing were sinus node dysfunction or A-V block. Leads were introduced through the subclavian vein. Atrial J-tined leads (27 silicone, 19 urethane) were positioned in the atrial appendage or stump in 46 patients, and coronary sinus or Bisping leads were placed in 4 patients; all 50 patients had tined ventricular leads. A Medtronic 5992 generator was placed in 35 patients and an Intermedics 259-01 generator in 15. Median implantation time was 105 minutes. Complications requiring reoperation in 409 patient-months of follow-up included lead retraction (one patient), phrenic nerve stimulation (one), pseudofracture (one), and atrial lead-induced "cross talk" (one). Monthly telephone transmission confirmed atrial capture in 35 patients and loss of capture in 1; the remainder had no identifiable P wave. Ventricular capture was confirmed in all. Postimplant and follow-up checks showed good stability of lead positions. We conclude that these systems have a low incidence of problems in short-term follow-up.  相似文献   
75.
The purpose of this paper is the assessment of sinus node competence over time in patients with isolated atrioventricular block (AV block). Patients implanted with AV synchronous pacemakers for isolated A V block between December 1993 and June 1995 were prospectively evaluated at predischarge, 6 weeks, and subsequent 6 months follow-up with respect to atrial rate monitors/24-hour Holter and modified exercise test. Patients unable to maintain AV synchronous pacing or complete a modified exercise test were excluded. Sinus node competency is interpreted as: (1) absence of atrial brady- or tach-yarrhythmia, (2) ability to achieve a minimum heart rate of 100 beats/min with modified exercise test or during daily activities. There were 58 patients (22 women), mean age 71.0 ± 13.8 with an average follow-up of 30.4 months (11–40). Three patients did not complete a modified exercise test, 4 patients were lost to follow-up, and 2 patients were unable to maintain AV synchronous pacing. Of the remaining 49 patients, 3 developed chronic or paroxysmal atrial fibrillation. No patient developed significant bradyarrhythmias. All patients achieved a heart rate of ≥ 100 beats/min modified exercise test. In our group of patients with isolated AV block within a moderate follow-up period, development of Sinoatrial dysfunction was rare (6%). A longer follow-up is required to delineate the natural history of Sinoatrial dysfunction in patients with isolated AV block.  相似文献   
76.
1. The effect of Irgasan DP 300 (5-chloro-2-(2,4-dichlorophenoxy)phenol) on cytochrome P450 (P450) induction and haem biosynthesis was studied in rat hepatocytes cultured on Matrigel. 2. Irgasan DP 300 significantly induced 7-benzyloxyresorufin O-debenzylase activity, followed by 7-pentoxyresorufin O-depentylase and 7-ethoxyresorufin O-deethylase activities. 4-Nitrophenol hydroxylase, testosterone 6β-hydroxylase and methoxyresorufin O-demethylase activities were also slightly increased. The maximum induction of these enzyme activities was obtained at the same concentration of 125 μM in the culture medium. 3. Immunochemical blots using anti-rat cytochrome P450 antibodies revealed that Irgasan DP 300 preferably induced CYP2B1/2 along with a slight increase in 3A. These results indicate that Irgasan DP 300 is a phenobarbital-type inducer. 4. In the absence of exogenous 5-aminolevulinic acid (ALA), slight increases in protoporphyrin IX (2·6-fold) and coproporphyrin III (1·3-fold) were observed in the Irgasan DP 300-treated cultures. In contrast, when 75 μM ALA was present, Irgasan DP 300 (250 μM) caused an extensive accumulation of uroporphyrin I (13-fold). 5. Irgasan DP 300 inhibited rat hepatic uroporphyrinogen III synthase in vitro. 6. These results indicate that Irgasan DP 300 produced accumulation of hydroxymethylbilane in rat hepatocytes by inhibiting uroporphyrinogen III synthase, and consequently an accumulation of uroporphyrin I.  相似文献   
77.
Terminal deoxynucleotidyl transferase (TdT) is a DNA polymerase located in the cell nucleus which catalyses the polymerization of deoxynucleotides at the 3′ hydroxyl ends of oligo- or polydeoxynucleotide initiators without a template. TdT is known as a useful marker for the diagnosis of acute lymphoblastic leukaemia/lymphoma, but its detection usually requires fresh tissue specimens or cell suspensions, using either an enzyme analysis or immuno-fluorescence or -peroxidase staining. Until the recent development of the use of microwave-treated paraffin sections for immunoperoxidase staining, detection of TdT in paraffin sections required rather complicated processes. This new simple technique was applied to paraffin sections from the tumour tissue specimens of 16 patients with lymphoblastic lymphoma and of seven patients with non-endemic Burkitt's lymphoma, which is sometimes difficult to differentiate from lymphoblastic lymphoma because of their similar clinicopathological characteristics. In addition, as a control, ten cases each were examined of adult T-cell leukaemia/lymphoma (ATLL) and angioimmunoblastic lymphoma (AILD), which are both peripheral T-cell lymphomas. The tumour cells from 15 of the 16 (94 per cent) patients with lymphoblastic lymphoma were found to be TdT-positive. The specificity of the anti-TdT antibody used was confirmed by immunoblot and the specific 60 kD band was detected only in a specimen of lymphoblastic lymphoma. These results show that the immunostaining of TdT on paraffin-embedded sections is a useful method for differentiating lymphoblastic lymphoma from other lymphomas. This method is applicable to a routine diagnostic service. © 1997 John Wiley & Sons, Ltd.  相似文献   
78.
Although coronary angiography has been the gold standard for assessing coronary artery stenoses, it yields information primarily about the anatomical severity of coronary artery disease, which frequently does not correlate with its physiological severity. Coronary interventions (PTCA, atherectomy, laser, etc.) are performed primarily to improve coronary flow physiology. Coronary flow physiology may be a more important end point than angiography following coronary interventions that were performed to normalize coronary flow physiology. In addition, the physiological significance of angiographically intermediate stenoses should he assessed before proceeding with catheter-based revascularization. Currently, the Doppler guidewire is available for routine clinical assessment of coronary flow physiology in the Cardiac Catheterization Lab. Several Doppler measurements have been used to assess the physiological effect of a stenosis, including the diastolic-systolic velocity ratio, proximal-distal velocity ratio, coronary flow reserve, continuity equation, and the hyperemic diastolic pressure-flow relationship. The Doppler derived coronary flow reserve correlates highly with stress nuclear perfusion images. These Doppler measurements have been made following PTCA, directional atherectomy, rotational atherectomy, and excimer laser. Following coronary interventions, adverse clinical events may be predicted if there is impaired flow physiology or cyclic flow variations. Many of the Doppler measurements used for assessing the lesion severity remain abnormal following successful coronary interventions for reasons unrelated to the lesion. Conversely, normalization of coronary physiology does not guarantee an adequate anatomical result. Further clinical trials will provide a more complete definition of the exact role for coronary flow velocity assessment following coronary interventions. (J Interven Cardiol 1996;9:163–173)  相似文献   
79.
In the present study, intestinal apo A-IV synthesis was investigated using a carbon tetrachloride (CCl4)-induced cirrhosis rat model. Triglyceride (TG) content in rat cirrhotic liver was increased markedly by 170% (P< 0.001) and apo B was increased by 20% (P<0.05) compared with control levels. These results reflected the steatotic change in the liver. In contrast, TG levels in the small intestine of cirrhotic rats decreased significantly (P<0.01). In addition, intestinal apo A-IV (jejunum P< 0.001; ileum P< 0.01) and its mRNA levels (jejunum P< 0.01; ileum P< 0.05) were also reduced. The decreased apo A-IV content in the jejunum was confirmed by immunohistochemical analysis. These results indicate that intestinal apo A-IV synthesis in cirrhosis is suppressed, at least under the condition of an overnight fast. Therefore, decreased intestinal apo A-IV synthesis may relate to the decreased ability to absorb fat in cirrhosis, but a fat-loading study will be necessary to confirm this hypothesis. It is unknown from the present study why serum apo A-IV level is not significantly decreased, despite a reduction in apo A-IV synthesis. The clearance of apo A-IV by the liver may be delayed or apo A-IV synthesis may be rather markedly enhanced during fat absorption in liver cirrhosis.  相似文献   
80.
Eosinophilic gastroenteritis (EGE) is an inflammatory disease characterized by eosinophilic infiltration of the gastrointestinal tract accompanied by varying abdominal symptoms and usually by peripheral blood eosinophilia. Although the precise aetiology of EGE remains to be determined, contribution of allergic process to certain allergens, such as foods, drugs and parasites, has been repeatedly proposed as the pathogenesis of the disease. Here we report on a rare case of a woman who had extensive eosinophilic infiltration in the descending and rectal colon with a high titre of IgG antibody against Ascaris suum. The patient was successfully treated with prednisolone.  相似文献   
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