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71.
Left ventricular (LV) dimensions and shortening at rest and during treadmill exercise were examined before and after 4 weeks of pulmonary artery (PA) constriction in 6 conscious dogs. The dogs were preinstrumented with LV and right ventricular (RV) catheters, an LV micromanometer, a PA inflatable cuff occluder and ultrasonic crystals to measure an LV anteroposterior, a septal-lateral, an apex-base and a free wall segment chord. With PA constriction, RV pressures increased from 49 ± 42 ± 1 mm Hg (systolic/end-diastolic) to 104 ± 52 ± 1 at rest and from 71 ± 92 ± 1 to 133 ± 814 ± 2 at peak exercise (mean ± standard error of the mean). Heart rate, LV pressure and LV dP/dt were similar before and after RV pressure overload at rest and with exercise. During exercise at control, systolic shortening increased significantly in all chords. With chronic PA constriction at rest, shortening of all chords also remained normal despite decreases in end-diastolic dimensions, which were most marked in the septal-lateral chord (23% decrease, p <0.01). However, during exercise in the presence of RV pressure overload, septal-lateral shortening decreased 46% (p <0.01) despite increases in systolic shortening in the other chords similar to the control response. Therefore, although LV function at rest in chronic RV pressure overload is normal, exercise may induce regional abnormalities of LV contraction that appear to be mediated by a reduced contribution of the ventricular septum to LV ejection.  相似文献   
72.
We reviewed the records of the Mayo Clinic patients with known carcinoid syndrome in whom echocardiographic studies had been done. Nineteen patients had M-mode and 2-dimensional echocardiographic examinations, and 1 patient had an M-mode examination only. Of the 20 patients, 8 had no evidence by echocardiogram of carcinoid heart disease; 2 had changes in the tricuspid valve echogram suggestive of early carcinoid heart disease, and the other 10 patients had the following distinctive echocardiographic findings: (1) the pattern of right ventricular volume overload (enlarged right ventricle with abnormal septal motion); (2) abnormal right-sided valves, including (a) a striking appearance of the tricuspid valve, the leaflets appearing thickened, retracted, and fixed in a semiopen position throughout the cardiac cycle, and (b) thickened, retracted pulmonic valve cusps, when visualized; and (3) the left-sided valves and chambers rarely involved. These echocardiographic features are distinctive of advanced carcinoid heart disease and correlate closely with pathologic findings.  相似文献   
73.
胆红素代谢紊乱   总被引:3,自引:0,他引:3  
胆红素代谢紊乱的临床主要表现为黄疸,也是高胆红素血症的表征,同时为肝病最常见的症状之一,黄疸鉴别诊断在临床日常诊疗工作中占极其重要的地位。  相似文献   
74.
AIM: To document the concerns and expectations of parents of children with inflammatory bowel disease (IBD) within the context of a multidisciplinary IBD clinic, and to highlight the importance of a holistic approach to the care of these children. METHODS: The parents of 60 children with IBD were surveyed by mailed questionnaire. Parents were asked to provide details of their concerns regarding their child's condition and to express their expectations of medical care. In addition, enquiry was made in respect to the respondents' learning about IBD. RESULTS: Forty-six questionnaires (77%) returned. Fiftytwo percent of the patients were male. Patients were aged a mean of 10.9 (±4.1) years and diagnosed at an average age of 2.1 (±1.8) years previously. The most common concerns expressed by the parents related to the side- effects of medications and the future prospects for their child. Overall, parents were satisfied with aspects of care within the IBD clinic but many suggested additional personnel such as counselors or educators should be available. Parents also reported the need for continuing education and easy access to up-to-date information. CONCLUSION: Parents of children and adolescents with IBD have many common concerns regarding their child's condition. On-going attention to holistic care, including psychosocial and educational elements for patients and families, is appropriate in the context of the chronic and unpredictable nature of IBD.  相似文献   
75.
76.
《Indian heart journal》2019,71(6):481-487
BackgroundFrontal QRS-T angle (FQRST) has previously been correlated with mortality in patients with stable coronary artery disease, but its role as survival predictor after ST-elevation myocardial infarction (STEMI) remains unknown.MethodsWe evaluated 267 consecutive patients with STEMI undergoing reperfusion or coronary artery bypass grafting. Data assessed included demographics, clinical presentation, electrocardiograms, medical therapy, and one-year mortality.ResultsOf 267 patients, 187 (70%) were males and most (49.4%) patients were Caucasian. All-cause mortality was significantly higher among patients with the highest (101–180°) FQRST [28% vs. 15%, p = 0.02]. Patients with FQRST 1–50° had higher survival (85.6%) compared with FQRST = 51–100° (72.3%) and FQRST = 101–180° (67.9%), [log rank, p = 0.01]. Adjusting for significant variables identified during univariate analysis, FQRST (OR = 2.04 [95% CI: 1.31–13.50]) remained an independent predictor of one-year mortality. FQRST-based risk score (1–50° = 0 points, 51–100° = 2 points, 101–180° = 5 points) had excellent discriminatory ability for one-year mortality when combined with Mayo Clinic Risk Score (C statistic = 0.875 [95%CI: 0.813–0.937]. A high (>4 points) FQRST risk score was associated with greater mortality (32% vs. 19%, p = 0.02) and longer length of stay (6 vs. 2 days, p < 0.001).ConclusionFQRST represents a novel independent predictor of one-year mortality in patients with STEMI undergoing reperfusion. A high FQRST-based risk score was associated with greater mortality and longer length of stay and, after combining with Mayo Clinic Risk Score, improved discriminatory ability for one-year mortality.  相似文献   
77.
In a large kindred we have identified two siblings with the hitherto unreported PZ phenotype and eight other subjects with the MP phenotype. In subjects with the MP phenotype serum alpha1-antitrypsin levels are near the lower limits of normal. In contrast, subjects with the PZ phenotype have severely depressed alpha1-antitrypsin levels. One subject with the PZ phenotype at age 34 already shows evidence of obstructive lung disease. We found no convincing evidence of obstructive lung disease in family members with the MP phenotype. After purification of alpha1-antitrypsin from the serum, isoelectric focusing and acrylamide gel electrophoresis can be used to distinguish normal protein from the products of the PiP and PiZ alleles. Subjects with the PZ phenotype have more PiP than PiZ product.  相似文献   
78.

Background

Preeclampsia increases the risk of heart disease. Defects in the protease corin, including the variant T555I/Q568P found in approximately 12% of blacks, have been associated with preeclampsia and cardiac hypertrophy. The objective of this study was to investigate the role of corin and the T555I/Q568P variant in preeclampsia-associated cardiac alterations using genetically modified mouse models.

Methods

Virgin wild-type (WT) and corin knockout mice with or without a cardiac WT corin or T555I/Q568P variant transgene were mated at 3 or 6 months of age. Age- and genotype-matched virgin mice were used as controls. Cardiac morphology and function were assessed at gestational day 18.5 or 28 days postpartum by histologic and echocardiographic analyses.

Results

Pregnant corin knockout mice at gestational day 18.5 developed cardiac hypertrophy. Such a pregnancy-associated phenotype was not found in WT or corin knockout mice with a cardiac WT corin transgene. Pregnant corin knockout mice with a cardiac T555I/Q568P variant transgene developed cardiac hypertrophy similar to that in pregnant corin knockout mice. The cardiac hypertrophy persisted postpartum in corin knockout mice and was worse if the mice were mated at 6 instead of 3 months of age. There was no hypertrophy-associated decrease in cardiac function in pregnant corin knockout mice.

Conclusions

In mice, corin deficiency causes cardiac hypertrophy during pregnancy. Replacement of cardiac WT corin, but not the T555I/Q568P variant found in blacks, rescues this phenotype, indicating a local antihypertrophic function of corin in the heart. Corin deficiency may represent an underlying mechanism in preeclampsia-associated cardiomyopathies.  相似文献   
79.
80.
Familial type III hyperlipoproteinemia is almost always first diagnosed in adults; the two 16-yr-old probands with type III in this report represent only the fifth and sixth children reported with the disorder. S.E., a 16-yr-old female, and C.H., a 21-yr-old male, (with palmar xanthomas at age 16) had beta-migrating abnormal very low density lipoproteins (beta-VLDL), density less than 1.006. S.E.'s brother (age 21) and mother (age 57) had type III; her grandmother had beta-VLDL and elevated triglycerides, and a maternal uncle had type IV hyperlipoproteinemia. C.H.'s father had type III; a sister and paternal aunt had type IV hyperlipoproteinemia. It is important to consider the diagnosis of type III hyperlipoproteinemia in the pediatric age group, particularly in children from families with type III hyperlipoproteinemia.  相似文献   
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