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991.
992.
BACKGROUND: The renewed interest in mitral valve replacement with a pulmonary autograft encouraged us to perform this procedure in selected patients. METHODS AND RESULTS: From August 2000 to February 2002, 10 patients between 30 and 52 years of age with calcific mitral valvular disease underwent the Ross II procedure. Patients were either in New York Heart Association functional class III (7/10) or IV (3/10). Transthoracic echocardiography was done in all the patients to confirm the diagnosis. A pulmonary autograft was used to replace the diseased mitral valve. Intraoperative transesophageal echocardiography confirmed normal functioning of the autograft. There were 2 early deaths. The 8 survivors are in New York Heart Association functional class I with excellent autograft and homograft function at a follow-up of 2-20 months (mean 9 months). CONCLUSIONS: This procedure is a viable option for mitral valve replacement in patients with calcific mitral valve disease. However, the procedure is technically demanding and requires a valve bank.  相似文献   
993.
In this study, we evaluated the effectiveness of the statistic, Weighted Coherence in relation to the average or mean coherence in a particular frequency band after cross-spectral analysis. In time domain, correlation coefficient explains the relationship between two variables of interest, and a similar statistic in frequency domain using cross-spectral analysis is referred to as coherence, which is equivalent to the squared correlation coefficient and ranges from zero to unity. In this study, we show that weighted coherence is much more sensitive to various challenges within the same subject and also may be a more sensitive indicator of group differences in different frequency bands. Our data on normal subjects and patients with panic disorder during supine and standing postures during normal breathing, and also at different breathing rates throw new light on the sensitivity of this previously described novel index to quantify coherence between two related time series such as beat-to-beat heart rate and QT interval.  相似文献   
994.
Rheumatic fever is a multi system disease which occurs following infection with group A beta hemolytic streptococcus. It is commonest in the age group of 5-15 years but can occur in adults also. First degree atrioventricular block is a common manifestation of acute rheumatic fever and is included in the Jones criteria but Wenckebacks phenomena and complete heart block are relatively rare manifestations of rheumatic fever. Syncope occurring in acute rheumatic fever is also infrequently reported. We report the case of a 38-year-old male with rheumatic carditis who had advanced atrioventricular block which resulted in syncope and required a temporary pacemaker insertion.  相似文献   
995.
One of the more difficult and time-consuming diagnostic procedures in the cardiac catheterization laboratory is retrograde crossing of the severely stenotic aortic valve. Whereas patients with advanced aortic stenosis tend to be complicated and elderly, lengthy procedures can lead to a higher incidence of thrombo-embolic and vascular complications and relatively greater procedural blood loss. This report concerns the use of the Terumo Glidewire to facilitate passage through stenotic and tortuous peripheral arteries. © 1993 Wiiey-Liss, Inc.  相似文献   
996.
BACKGROUND: The angiotensin II type 2 receptor (AT2R) is considered to be antigrowth and to mediate apoptosis in several cell types. Whether AT2R upregulation, associated with angiotensin II type 1 receptor (AT1R) blockade and cardioprotection after ischemia-reperfusion (IR), might not result in increased cardiomyocyte (CM) apoptosis has not been documented. OBJECTIVES: To determine whether increased AT2R protein expression, during AT1R blockade after acute IR, is associated with no increase in CM apoptosis. MATERIALS AND METHODS: The recovery of left ventricular (LV) mechanical function after acute IR (30 min of ischemia, 40 min of reperfusion) was measured in isolated Langendorff rat hearts following pretreatment with the AT1R antagonist candesartan (CN) (CN 10 nmol/L) for 40 min before ischemia. The authors established with an initial dose-response curve using escalating concentrations of CN that 10 nmol/L abrogated vasoconstriction induced by angiotensin II (0.1 mmol/L). AT1R and AT2R protein expression (Western immunoblot), CM apoptosis (terminal deoxynucleotidyl transferase-mediated 2'-deoxyuridine 5'-triphosphate nick end-labelling assay and nuclear morphology) and apoptotic markers (Bax, Bcl-2, caspase-3, p53) were assessed in LV tissue. RESULTS: Compared with IR controls, CN improved peak systolic pressure, LV developed pressure and positive dp/dt, and increased AT2R (not AT1R) protein, but did not change the level of apoptosis or the expression of Bax, Bcl-2, caspase-3 or p53. CN also increased AT2R protein after ischemia alone but did not change CM apoptosis or expression of the markers. CONCLUSIONS: Increased AT2R protein expression during AT1R blockade after IR in the isolated Langendorff rat heart is associated with cardioprotection but no increase in CM apoptosis.  相似文献   
997.
Cytomegalovirus (CMV) can be classified into 4 glycoprotein B (gB) genotypes, on the basis of sequence variation in the UL55 gene. We assessed the effect that CMV gB genotype has on virologic and clinical response to therapy, in 50 solid-organ-transplant recipients with CMV disease. CMV loads were determined at regular intervals after the start of therapy. Genotype results were correlated with CMV-load kinetics in response to therapy with ganciclovir. At the onset of treatment, the distribution of CMV gB genotypes was as follows: gB1, 19/50 (38%); gB2, 9/50 (18%); gB3, 12/50 (24%); gB4, 2/50 (4%); and mixed-genotype infection, 8/50 (16%). Between viral genotype groups, time to clearance of CMV, failure to clear CMV, and calculated CMV-load half-life after the start of therapy were not significantly different. The CMV gB genotype did not affect the rate of disease recurrence or occurrence of tissue-invasive disease. It appears that the gB genotype, which causes CMV disease, does not significantly influence CMV-load kinetics or clinical response to therapy.  相似文献   
998.
In the present study, the effects of morphine and pethidine on coronary vessel resistance (CPP), blood pressure (BP), and experimental myocardial infarction-induced cardiac arrhythmia were investigated. Both morphine and pethidine induced a fall in CPP and BP and inhibited the cardiac arrhythmia. The morphine effects on CPP and BP were largely blocked by mepyramine. The effects of pethidine, on the other hand, were not blocked by mepyramine, propranolol, or atropine. An interesting dose dependent inhibition of cardiac arrhythmia was observed with pethidine.  相似文献   
999.

Background

It is being increasingly reported that some of the youth onset diabetes patients cannot be classified clearly as type 1 diabetes mellitus (T1DM) or type 2 diabetes mellitus (T2DM) based on usual criteria and the term double diabetes (DD) coined for these cases.

Aim

The objective of the study was to find out the prevalence of DD in youth onset diabetes patients from east Delhi and neighboring NCR region.

Methods

A total of 200 patients with youth onset diabetes below 25 years of age were recruited from a tertiary care hospital in East Delhi. Clinical history, family history of diabetes and anthropometry of patients were recorded. Fasting serum C-peptide, Anti-IA2-antibody and Anti-GAD-antibody were measured in all patients. Patients positive for Anti-GAD-antibody (>1.05 U/ml) and C-peptide level >0.3 nmol/l were characterized as DD patients. Patients negative for Anti-GAD-antibody and C-peptide >0.3 nmol/l were kept under the category of T2DM. Patients with low C-peptide level along with one of the following, positive Anti-GAD-antibody, positive Anti-IA2-antibody and diabetic ketoacidosis (DKA) were considered as T1DM. Remaining patients were kept under the unknown category.

Results

Mean age of study subjects was 18.2 ± 7.1 years. Seven percent (7%) of the subjects were classified as DD, 51% as T1DM, 13% as T2DM and 29% were kept under the unknown category. Mean age of subjects with 22.2 ± 9.7, 16.9 ± 6.7, 20.6 ± 7.7 and 19.4 ± 7.4 years in DD, T1DM, T2DM and unknown category respectively. Mean BMI of subjects with DD, T1DM, T2DM and unknown category was 19.8 ± 5.7, 16.6 ± 3.7, 19.3 ± 4.1 and 18.0 ± 4.6 kg/m2 respectively.

Conclusion

Double diabetes is an important occurrence among youth onset diabetes subjects. Only half of the subjects with youth onset of diabetes had T1DM.  相似文献   
1000.
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