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31.
M Nair R Arora J C Mohan G S Kalra K K Sethi M Nigam M Khalilullah 《International journal of cardiology》1991,32(3):389-394
Cross-sectional and Doppler echocardiography are currently the most important non-invasive tests for the evaluation of mitral stenosis. Recent experience has, however, shown that parameters that are reliable before mitral valvotomy may not be valid after the procedure. We have studied the validity of estimation of the area of the mitral valve by echo-planimetry, by Doppler pressure half time and the transmitral end-diastolic pressure gradient calculated by continuous wave Doppler in 100 patients (aged 10-30 years) before and after balloon mitral valvoplasty (n = 70) or surgical closed mitral valvotomy (n = 30). These patients underwent cardiac catheterisation and echocardiographic studies before, immediately after and 8-12 (9.3 +/- 2.2) weeks following balloon valvoplasty or closed valvotomy. The area as estimated echocardiographically correlated well with that obtained by the Gorlin formula before (r = 0.80), but not immediately after (r = 0.67) or on follow up after mitral valvotomy. There was good correlation between Doppler pressure half time and the area as estimated by the Gorlin formula before (r = 0.89) and on follow up after valvotomy (r = 0.82), but the correlation was not as good in the immediate period after valvotomy (r = 0.60). The end-diastolic pressure gradients obtained by Doppler examination and at cardiac catheterisation correlated well with each other before (r = 0.94), immediately after valvotomy (r = 0.92) and on follow up (r = 0.94). Hence, the reliability of estimation of the area of the mitral valve by echo-planimetry and by Doppler pressure half time varies according to the time at which the examination is performed following commissurotomy.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
32.
Dhindsa S Prabhakar S Sethi M Bandyopadhyay A Chaudhuri A Dandona P 《The Journal of clinical endocrinology and metabolism》2004,89(11):5462-5468
Type 2 diabetes is associated with lower total testosterone (T) levels in cross-sectional studies. However, it is not known whether the defect is primary or secondary. We investigated the prevalence of hypogonadism in type 2 diabetes by measuring serum total T, free T (FT), SHBG, LH, FSH, and prolactin (PRL) in 103 type 2 diabetes patients. FT was measured by equilibrium dialysis. FT was also calculated by using T and SHBG (cFT). Hypogonadism was defined as low FT or cFT. The mean age was 54.7 +/- 1.1 yr, mean body mass index (BMI) was 33.4 +/- 0.8 kg/m(2), and mean HbA1c was 8.4 +/- 0.2%. The mean T was 12.19 +/- 0.50 nmol/liter (351.7 +/- 14.4 ng/dl), SHBG was 27.89 +/- 1.65 nmol/liter, and FT was 0.250 +/- 0.014 nmol/liter. Thirty-three percent of patients were hypogonadal. LH and FSH levels were significantly lower in the hypogonadal group compared with patients with normal FT levels (3.15 +/- 0.26 vs. 3.91 +/- 0.24 mIU/ml for LH and 4.25 +/- 0.45 vs. 5.53 +/- 0.40 mIU/ml for FSH; P < 0.05). There was a significant inverse correlation of BMI with FT (r = -0.382; P < 0.01) and T (r = -0.327; P < 0.01). SHBG correlated inversely with BMI (r = -0.267; P < 0.05) but positively with age (r = 0.538; P < 0.001) and T (r = 0.574; P < 0.001). FT correlated strongly with cFT (r = 0.919; P < 0.001) but not with SHBG. LH levels correlated positively with FT (r = 0.287; P < 0.05). We conclude that hypogonadotropic hypogonadism occurs commonly in type 2 diabetes. 相似文献
33.
Douglass A Morrison Gulshan Sethi Jerome Sacks William Henderson Frederick Grover Steven Sedlis Rick Esposito Kodagundi B Ramanathan Darryl Weiman J David Talley Jorge Saucedo Tamim Antakli Venki Paramesh Stuart Pett Sarah Vernon Vladimir Birjiniuk Frederick Welt Mitchell Krucoff Walter Wolfe John C Lucke Sundeep Mediratta David Booth Charles Barbiere Dan Lewis 《Journal of the American College of Cardiology》2002,39(2):266-273
OBJECTIVES: This study was designed to compare the three-year survival after percutaneous coronary intervention (PCI) or coronary artery bypass graft surgery (CABG) in physician-directed and patient-choice registries with the Angina With Extremely Serious Operative Mortality Evaluation (AWESOME) randomized trial results. BACKGROUND: The AWESOME multicenter randomized trial and registry compared the long-term survival after PCI and CABG for the treatment of patients with medically refractory myocardial ischemia and at least one additional risk factor for adverse outcome with CABG. The randomized trial demonstrated comparable three-year survival. METHODS: Over a five-year period (1995 to 2000), 2,431 patients with medically refractory myocardial ischemia and at least one of five risk factors (prior heart surgery, myocardial infarction within seven days, left ventricular ejection fraction <0.35, age >70 years, intra-aortic balloon required to stabilize) were identified. By physician consensus, 1,650 patients formed a physician-directed registry assigned to CABG (692), PCI (651) or further medical therapy (307), and 781 were angiographically eligible for random allocation; 454 of these patients constitute the randomized trial, and the remaining 327 constitute a patient choice registry. Survival for CABG and PCI was compared using Kaplan-Meier curves and log-rank tests. RESULTS: The CABG and PCI 36-month survival rates for randomized patients were 79% and 80%, respectively. The CABG and PCI 36-month survival rates were both 76% for the physician-directed subgroup; comparable survival rates for the patient-choice subgroup were 80% and 89%, respectively. None of the global log-rank tests for survival demonstrated significant differences. CONCLUSIONS: Both registries support the randomized trial conclusion: PCI is an alternative to CABG for some medically refractory high-risk patients. 相似文献
34.
Storage temperature and differing methods of sample preparation in the measurement of urinary albumin 总被引:1,自引:0,他引:1
Ms A. C. G. Collins M. Sethi F. A. MacDonald D. Brown G. C. Viberti 《Diabetologia》1993,36(10):993-997
Summary Microalbuminuria is a predictor of persistent proteinuria, renal failure and cardiovascular disease and therefore accurate
determination of urinary albumin concentration is important. We examined the stability of albumin in urine under different
conditions of storage, temperature and sample preparation. There was no significant difference in urinary albumin concentration
between fresh urine and urine stored at either 4°C or 20°C for up to 7 days. Similarly in urine samples from diabetic patients
there was no significant difference in albumin concentration at levels ranging from 1.3 to 1999.3 mg/l between fresh urine
at 4°C and urine stored frozen for 1 week, 1 month or 6 months. Neither storage temperature (−20°C or −40°C) nor centrifugation
of sample prior to assay made a significant difference to the albumin concentration. Multiple freezing and thawing of urine
samples during 6 weeks of storage at −20°C made no difference to albumin concentrations. Storage of urine samples in either
polypropylene, polystyrene or borosilicate glass tubes did not result in a significant change in urinary albumin concentration
after either 1 week or 1 month at −20°C although, after 1 month of storage, urinary albumin concentrations tended to be lower
by an average of approximately 7%. In tubes to which gelatine had been added this was reduced to 4%. We conclude that fresh
urine can be kept at 4°C or 20°C for up to 7 days. Frozen urine samples can be stored for up to 6 months before assay without
any loss of albumin concentration. Polypropylene, polystyrene or borosilicate glass tubes are acceptable containers for short-term
storage and samples can simply be thoroughly thawed and vortex mixed immediately prior to assay. 相似文献
35.
An unusual case of Holt-Oram syndrome with arachnodactyly, high arch palate, thoracic scoliosis and hypoplasia of the left radial artery is reported. The relevant literature is discussed and the importance of vascular hypoplasia in genesis and localization of the skeletal deformities of this syndrome is stressed. 相似文献
36.
SUMMARY
This review article introduces the significance of testing of volatile organic compounds (VOCs) in clinical samples and summarizes important features of some of the technologies. Compared to other human diseases such as cancer, studies on VOC analysis in cases of infectious diseases are limited. Here, we have described results of studies which have used some of the appropriate technologies to evaluate VOC biomarkers and biomarker profiles associated with infections. The publications reviewed include important infections of the respiratory tract, gastrointestinal tract, urinary tract, and nasal cavity. The results highlight the use of VOC biomarker profiles resulting from certain infectious diseases in discriminating between infected and healthy subjects. Infection-related VOC profiles measured in exhaled breath as well as from headspaces of feces or urine samples are a source of information with respect to disease detection. The volatiles emitted in clinical matrices may on the one hand represent metabolites of the infecting pathogen or on the other hand reflect pathogen-induced host responses or, indeed, a combination of both. Because exhaled-breath samples are easy to collect and online instruments are commercially available, VOC analysis in exhaled breath appears to be a promising tool for noninvasive detection and monitoring of infectious diseases. 相似文献37.
Elsayed Mohammad Cheng Bernard Xing Minzhi Sethi Ila Brandon David Schuster David M. Bercu Zachary Galt James Barron Bruce Kokabi Nima 《Cardiovascular and interventional radiology》2021,44(2):254-260
CardioVascular and Interventional Radiology - To compare lung shunt fraction (LSF) prior to Y-90 radioembolization calculated using planar imaging versus SPECT/CT in patients with hepatocellular... 相似文献
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