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51.
Koenig S Shafie M Pearson A Laureano MA Cerrito P Ewert D Schroeder M Dowling RD 《Journal of cardiac surgery》1999,14(2):152-156
Partial left ventriculectomy (PLV) has been introduced as an alternative surgical therapy for patients with end-stage dilated cardiomyopathy. The physiological benefits of PLV are relatively unknown. Therefore, the objective of this study was to determine the acute effects of PLV by measuring cardiac function before and after PLV. Aortic and left ventricular pressures and aortic flow were measured in eight patients. Continuous, beat-to-beat data were recorded and compared pre-PLV and post-PLV with and without inferior vena cava (IVC) occlusions. PLV increased cardiac output (0.93+/-0.5, p = 0.01) as a result of increased stroke volume (5.12+/-4.24, p = 0.06) and heart rate (14.5+/-8.44, p = 0.02). Contractility (+/- dP/dt, 240.33+/-74.28, p = 0.001) and external work (650.8+/-320.4, p = 0.01) were also improved. Left ventricular end-diastolic elastance (0.15+/-0.14, p = 0.10) nearly doubled after PLV. Our results indicated an improved cardiac function as measured by increased cardiac output, stroke volume, ejection fraction (EF), and contractility. 相似文献
52.
53.
This article addresses the need for improved clergy-mental health professional collaboration in the assessment and treatment of elderly suicide. Millions of older adults with personal problems seek the counsel of clergy. A recent Gallup survey found that elders are more willing to turn to their clergy than their medical doctor or a mental health specialist for help when a friend is contemplating suicide (Gallup Organization, 1992). Elder suicide prevention presents the mental health and religious communities with unique opportunities to work together in the best interests of those they serve. 相似文献
54.
Molecular markers reveal cryptic sex in the human pathogen Coccidioides immitis. 总被引:4,自引:0,他引:4
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A Burt D A Carter G L Koenig T J White J W Taylor 《Proceedings of the National Academy of Sciences of the United States of America》1996,93(2):770-773
Coccidioides immitis, cause of a recent epidemic of "Valley fever" in California, is typical of many eukaryotic microbes in that mating and meiosis have yet to be reported, but it is not clear whether sex is truly absent or just cryptic. To find out, we have undertaken a population genetic study using PCR amplification, screening for single-strand conformation polymorphisms, and direct DNA sequencing to find molecular markers with nucleotide-level resolution. Both population genetic and phylogenetic analyses indicate that C. immitis is almost completely recombining. To our knowledge, this study is the first to find molecular evidence for recombination in a fungus for which no sexual stage has yet been described. These results motivate a directed search for mating and meiosis and illustrate the utility of single-strand conformation polymorphism and sequencing with arbitrary primer pairs in molecular population genetics. 相似文献
55.
Frank Koenig Francis J. McGovern Alex F. Althausen Thomas F. Deutsch Kevin T. Schomacker 《The Journal of urology》1996,156(5):1597-1601
Purpose
We assessed the ability of laser induced autofluorescence to differentiate malignant from nonmalignant bladder lesions.Materials and Methods
We studied 53 patients with bladder cancer undergoing mucosal biopsies or transurethral resection of a bladder tumor. A quartz optical fiber was advanced through the working channel of a cystoscope and placed in gentle contact with the bladder. Tissue fluorescence was excited by 337 nm. light pulses (nitrogen laser). One fiber was used for transmission of the excitation and emission (fluorescence) light. An optical multichannel analyzer system was used to record fluorescence spectra of the sites of interest.Results
We analyzed the fluorescence spectra of 114 bladder areas (1 carcinoma in situ as well as 28 malignant, 35 inflammatory, 7 dysplastic, 1 squamous metaplastic and 42 normal areas). These lesions included 44 difficult to diagnose suspicious tumors (11 malignant and 33 nonmalignant). We developed an algorithm that used the I385:I455 nm. fluorescence ratio to distinguish malignant from nonmalignant lesions, including inflammatory areas. By analyzing the data on all 114 lesions, we noted the sensitivity, specificity, and positive and negative predictive values of this method for differentiating malignant from nonmalignant bladder lesions to be 97, 98, 93 and 99 percent, respectively.Conclusions
Under excitation with 337 nm. light a clear differentiation between malignant and nonmalignant bladder tissues can be made using the I385:I455 nm. autofluorescence ratio. 相似文献56.
S. B. Greenberg Kristin L. Crisci Peter Koenig Brad Robinson Paul Anisman P. Russo 《Pediatric radiology》1997,27(12):932-935
Background. Abnormalities of the pulmonary arteries following palliative or corrective surgery for tetralogy of Fallot (TOF) are common.
Our purpose was to compare the usefulness of magnetic resonance imaging (MRI) and echocardiography in the post- operative
evaluation of the pulmonary arteries in children with TOF. Objective. Our hypothesis was that MRI is more sensitive than echocardiography in the detection of branch pulmonary artery abnormalities
in children with TOF. Materials and methods. Pulmonary artery MRI and echocardiography were performed in 20 children following palliative and/or corrective surgery for
TOF. MRI and echocardiography were compared in their ability to detect abnormalities of the pulmonary arteries. Angiographic
or surgical correlation was available in 15 children. A perfusion scan for confirmation of pulmonary artery patency was available
in one additional child. Results. Abnormalities of the branch pulmonary arteries identified by MRI included: absence or occlusion (2), focal stenosis (15),
hypoplasia (2), aneurysm (1), and non-confluence (1). Echocardiography could not adequately visualize the right and left branch
pulmonary arteries in eight and ten children, respectively. Echocardiography missed stenosis in 13 branch pulmonary arteries,
patency of hypoplastic pulmonary arteries in two children, non-confluence of the pulmonary arteries in one child, and a left
pulmonary artery aneurysm in one child. Abnormalities identified by MRI were confirmed in 16 children by angiography, surgery
or perfusion scan. Conclusion. MRI is more sensitive than echocardiography for the evaluation of branch pulmonary artery abnormalities in children following
surgery for TOF.
Received: 13 January 1997 Accepted: 31 July 1997 相似文献
57.
W. Koelfen M. Freund D. Dinter B. Schmidt S. Koenig C. Schultze J. Runde 《European journal of pediatrics》1997,156(3):230-235
The primary issues addressed in this study were: (1) determination of the significance of the classification “good outcome”
utilizing the Glasgow Outcome Scale (GOS) in children at least 1 year after brain injury; (2) detection of residual lesions
of brain parenchyma in these children upon follow up MRI scans; and (3) detection of relationships between neuropsychological
test performance and MRI results. Selection criteria included children 6–15 years of age at the time of testing who received
an initial CT scan at the time of their head injury and who had been injured at least 12 months prior to the follow up test.
Only children who did not demonstrate neurological disability at the time of follow up examination were selected. The children
showed a status of “good outcome” as defined by the GOS. Neurological examination, neuropsychological tests and an MRI were
done. The test results of 59 patients were compared to those of a matched control group. Children, after receiving head injuries,
showed significantly poorer results with respect to cognitive, motor and fine motor skills. Of all MRI-scans 66% revealed
pathological findings. Cortical lesions were detected on MRI in 14% of cases; subcortical injuries were detected in 12% and,
deep white matter lesions in 31%. Furthermore, corpus callosum damage was observed in 26% of cases. Pathological MRI findings
were also observed in children with mild head injuries. All of the children with normal MRI findings showed abilities comparable
to those of children in the control group. Patients with cortical lesions exhibited only motor deficits, whereas motor and
cognitive deficits were seen in patients with deep white matter lesions. Children with multiple lesions demonstrated test
results in all variables 1 to 2 standard deviations below those of the control group.
Conclusions Children suffering a brain injury who 1 year later are classified within the “good outcome” group according to the Glasgow
Outcome Scale often have significant morphological and functional brain deficits.
Received: 6 January 1996 / Accepted: 10 August 1996 相似文献
58.
OBJECTIVES: To investigate maternal knowledge and attitudes about otitis media (OM) risk, to estimate the prevalence of risk factors in the first year of life, and to identify barriers to the reduction of risk factors (eg, formula feeding, day care attendance, and exposure to passive smoke). METHODS: Questionnaires mailed to a systematic sample of 504 Minnesota women >/=18 years old identified through 1994 birth certificates. RESULTS: Eighty percent returned a completed survey. According to maternal report, 29% of infants (age 8 to 13 months) had recurrent OM (>/=3 episodes) and 2% had tympanostomy tubes. Forty-six percent attended day care, 29% had >/=1 smoking parent, and 49% breastfed for =2 months. Women were more knowledgeable about OM signs and symptoms than about risk factors. Mean OM knowledge score (the sum of correct true-false responses) was 7.0 (standard deviation = 1.6). Using multiple linear regression, knowledge score was significantly related to marital status, education, age, area of residence, breastfeeding (months), and number of cigarettes smoked per day by the mother, but not to infant or sibling OM history or day care attendance (R = .23). Infant history of OM (odds ratio, 1.9; 95% confidence interval, 1.1 to 3.2) and white race (odds ratio, 0.3; 95% confidence interval, 0. 1 to 0.8), but not the presence of risk factors, were significantly related to having received clinicians' advice about OM prevention advice. CONCLUSION: OM education and prevention programs should target pregnant women and new mothers with OM risk factors, and those who are young, single, and less educated. 相似文献
59.
Dietary polyamines promote the growth of azoxymethane-induced aberrant crypt foci in rat colon 总被引:1,自引:1,他引:1
We have examined whether dietary polyamines influence the formation and
initial growth of azoxymethane (AOM)-induced aberrant crypt foci (ACF) in
rat colon. Effects of a combination of dietary polyamines at three dose
levels (putrescine: 50, 280, 740 nmol/g; spermidine: 10, 261, 763 nmol/g;
spermine: 1, 31, 91 nmol/g) in the polyamine-poor AIN-76A diet were studied
in animals in two different experimental situations: animals treated with
AOM alone and animals treated with AOM + difluoromethylornithine (DFMO), a
specific inhibitor of endogenous polyamine synthesis. In both experimental
situations, dietary polyamines enhanced the growth of ACF, expressed as the
number of large ACF (foci with three or more aberrant crypts, ACF > or =
3), whereas the formation of ACF, expressed as the number of ACF, was
apparently not altered. In animals treated with AOM alone, maximal growth
enhancing effect on ACF was nearly obtained with the median level of
dietary polyamine. In rats fed a low polyamine diet, basic AIN-76A, DFMO
reduced the growth of AOM-induced ACF by 83%. This inhibitory effect of
DFMO was counteracted by dietary polyamines in a dose- dependent manner,
and it was abolished at the highest level of polyamines. In conclusion, it
was demonstrated that dietary polyamines are able to enhance the growth of
AOM-induced ACF. Further, dietary polyamines reversed the DFMO-caused
inhibition of ACF growth, probably by compensating for the DFMO-reduced
endogenous polyamine synthesis.
相似文献
60.