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11.
J M Abarbanel P Ashby A Marquez-Julio K R Chapman 《The Canadian journal of neurological sciences. Le journal canadien des sciences neurologiques》1991,18(3):349-351
A Caucasian girl developed slowly progressive sensory neural deafness and bulbar and spinal muscle weakness typical of the Vialetto-Van Laere syndrome. As the condition progressed the major disabilities became dysphagia, respiratory muscle weakness and postural hypotension. Treatment with gastrostomy feedings, oxygen and fludrocortisone acetate produced worthwhile functional improvement. 相似文献
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D R Charnock G D Chapman R E Taylor A Wozniak 《Archives of otolaryngology--head & neck surgery》1992,118(5):507-508
The core tissue microflora of 40 patients who underwent tonsillectomies were examined with cultures, DNA probe tests, enzyme immunoassays, and direct immunofluorescence antibody tests for Chlamydia and Mycoplasma. We believe this is the largest and most accurate prospective study that has examined the role of Chlamydia and Mycoplasma in the core tonsil tissue of patients with recurrent or chronic tonsillitis. The data strongly indicate that, unlike acute tonsillopharyngitis, Chlamydia and Mycoplasma are not involved in recurrent or chronic tonsillitis. 相似文献
15.
Metabolism of benzene by the liver has been suggested to play an important role in the hepatotoxicity of benzene. The role of the different benzene metabolites and the causes of species differences in benzene hepatotoxicity are, however, not known. The metabolism and covalent binding of 14C-benzene by liver microsomal fractions and liver slices from rat, mouse, and human subjects have been studied. Rat microsomal fraction formed phenol at a rate of 0.32 nmol/min/mg of protein; mouse microsomal fraction formed phenol at 0.64 nmol/min/mg and hydroquinone at 0.03 nmol/min/mg; and human microsomal fraction formed phenol at 0.46 nmol/min/mg and hydroquinone at 0.07 nmol/min/mg. Covalent binding of 14C-benzene metabolites to rat, mouse, and human liver microsomal protein was 29, 113, and 169 pmol/min/mg of protein, respectively. The rates of metabolite formation from benzene by liver slices in nmol/min/g of tissue were: rat, phenol 0.15, hydroquinone 0.26, and phenylsulfate 1.22; mouse: phenol 0.13, hydroquinone 0.29, phenylsulfate 1.37, and phenylglucuronide 1.34; and human: phenol 0.16, hydroquinone 0.27, phenylsulfate 0.83, and phenylglucuronide 0.52. trans,trans-Muconic acid formation was not detected with liver slices of any species. Covalent binding of 14C-benzene metabolites to rat, mouse, and human liver slices was 8.2, 79.7, and 27.3 pmol/min/g liver, respectively. There was no correlation between ascorbic acid levels in the human liver slices and covalent binding of 14C-benzene metabolites. The results show that phenol and hydroquinone found in extrahepatic tissues, including bone marrow, of animals exposed to benzene could originate from the liver. There was no evidence for the release of highly reactive benzene metabolites such as trans,trans-muconaldehyde or p-benzoquinone from liver cells.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
16.
H L Anderson R J Attorri J R Custer R A Chapman R H Bartlett 《The Journal of thoracic and cardiovascular surgery》1990,99(6):1011-9; discussion 1019-21
Extracorporeal membrane oxygenation is now standard treatment of severe respiratory failure in newborn infants in our center (200 cases) and worldwide (over 2500 cases), but there are few reports of such trials in older children. We reviewed our experience with extracorporeal membrane oxygenation in 33 children aged 1 week to 18 years between 1971 and 1989. The modality was used when all other treatment failed. Extracorporeal membrane oxygenation provided excellent cardiopulmonary support for 1 to 25 days (average 7 1/2 days). The survival rate was 25% for cardiac support patients and 47% for respiratory failure patients (36% overall survival). Mechanical complications included membrane lung failure, tubing rupture, and pump failure, all managed without mortality. Physiologic complications included bleeding, pneumothorax, cardiac arrest, renal failure, hepatic failure, and brain injury. The major cause of death was irreversible injury to lung, heart, or brain. Extracorporeal life support is a reasonable approach for children with serious but reversible cardiopulmonary failure. 相似文献
17.
Cellular models and tissue equivalent systems for evaluating the structures and significance of age-modified proteins 总被引:1,自引:0,他引:1
R W Gracy K U Yüksel T M Jacobson M L Chapman J C Hevelone G E Wise S D Dimitrijevich 《Gerontology》1991,37(1-3):113-127
The accumulation of modified proteins in aging is well documented in many aging models. For example, the deamidated isoforms of triosephosphate isomerase accumulate in: (a) old erythrocytes, (b) fibroblasts from old donors, (c) fibroblasts aged in vitro, (d) premature-aging syndromes and (e) old cells in the eye lens. However, a fundamental remaining question is: 'Do such modified proteins interfere with cellular function?' It has been difficult to assess this question at the molecular level using whole-organism models and equally frustrating to evaluate the physiological significance of such changes using classical cellular models. Tissue equivalent systems (TES) provide an opportunity for examining the molecular basis and physiological consequences of modified proteins during aging. TES are composed of differentiating and proliferating heterogeneous cell types with symbiotic cell-cell and cell-matrix interactions. They closely resemble, both morphologically and functionally, the tissues from which they were derived. Aging studies utilizing TES can provide information on modifications of protein structures, isozyme patterns, enzymes of the cellular environmental protection system and metabolic parameters which may regulate protein synthesis and degradation. 相似文献
18.
Because attitudes concerning a topic can diminish the effectiveness of educational materials, previously identified attitudes concerning calcium intake were explored through focus group interviews during the developmental stages of calcium education materials. Although four focus groups of six to seven participants were planned, each of the four groups consisted of two to six women. All focus groups followed the same format, lasting for 60–90 min; questions progressed from the general to more specific. The focus groups revealed several attitudinal barriers toward dietary behavioural change, including lack of prior interest in the topic and lack of time. Attitudes about dairy calcium included the belief that dairy foods were high in fat and should be avoided, and the belief that dairy foods would cause stomach upsets. Also, neither younger nor older women felt that osteoporosis was a problem their age group needed to address. Readability scales were not necessarily predictive of preference. This study shows that focus group interviews make a valuable contribution to planning and evaluating nutrition education materials. 相似文献
19.
Duane C. Chapman 《Archives of environmental contamination and toxicology》1992,22(3):296-299
Young striped bass (Morone saxatilis) with uninflated gas bladders were less sensitive to selenate and more sensitive to selenite exposure than normally developing striped bass in 96-hour acute toxicity tests. Gas bladder inflation failure is a common problem in the culture of striped bass and some other species, and care should be taken to avoid the use of fish with uninflated gas bladders in research. 相似文献
20.
Twenty-nine females with metastatic or locally recurrent carcinoma of the breast were treated orally with 1 g of medroxyprogesterone acetate (MPA) daily. This was used as a second- or third-line treatment. Serum concentration of MPA was measured over a 28-day period. We have demonstrated a significantly greater area-under-the-concentration-time curve, peak, and steady-state MPA concentration for Provera at 100- and 200-mg tablets (Upjohn) than for Farlutal at 500-mg tablets (Farmitalia). Relative bioavailability of preparations should be considered when prescribing or assessing treatment results when MPA is used. 相似文献