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31.
Nonneural granular cell tumors (NNGCTs) are rare benign neoplasms originally described in 1991 by Leboit et al. Typical granular cell tumors (GCTs) are commonly encountered in the oral cavity, but NNGCTs, unlike GCTs, are S-100 negative and may display cytologic atypia, allowing for misdiagnosis as a more aggressive lesion. We report a case of a 43-year-old male with a lesion of the mandible that we believe to be the first intraoral example of an NNGCT.  相似文献   
32.
Closed head injured patients demonstrated greater anticipatory behaviour deficit than cerebral vascular accident patients on a shuttlebox-analog avoidance task, even though these two groups did not differ on escape behaviour and on performance on the individual tests of the Halstead-Reitan Battery and Wechsler scales. Neither clarification of instructions, additional trials, nor enhancement of the warning cue appeared to improve the anticipatory behaviour deficit. It was concluded that anticipatory behaviour deficit should be considered a relatively dense deficit that is not identified by standard instruments. Clinical and practical implications are discussed.  相似文献   
33.
Total lower abdominal wall resection was required to remove a recurrent exophytic bladder carcinoma in a 36-year-old woman. The resulting 25 x 30-cm fascial defect was repaired with Marlex mesh. Bilateral rectus femoris myocutaneous flaps were rotated to close the 25 x 18-cm area of skin deficiency. These provided the advantages of robust cover of the lower abdominal wall in a single-stage procedure and primary closure of the donor sites.  相似文献   
34.
The relation of body fat distribution to plasma levels of glucose and insulin during an oral glucose tolerance test was examined in 355 Black and White school-age children. Both central and peripheral fat were similarly related to fasting, 30-min, and 1-h glucose. Unlike peripheral fat, central body fat was more strongly related to the 1-h insulin response (r = 0.35 vs 0.26); this association remained significant for central fat independent of peripheral fat (r = 0.18). The strong relation of central fat to insulin response was noted in both races and sexes but not in either sexually immature or relatively thin children. These findings indicate that, even in early life, a central body fat pattern relates positively to insulin response to glucose load. Thus, knowledge of body fat localization may help identify persons most susceptible to hyperinsulinemia in early life.  相似文献   
35.
Background: Sevoflurane undergoes Baralyme- or soda lime-catalyzed degradation in the anesthesia circuit to yield compound A (2-[fluoromethoxy]-1,1,3,3,3-pentafluoro-1-propene), which is nephrotoxic in rats and undergoes metabolism via the cysteine conjugate beta-lyase pathway in those animals. The objective of these experiments was to test the hypothesis that compound A undergoes beta-lyase-dependent metabolism in humans.

Methods: Human volunteers were anesthetized with sevoflurane (1.25 minimum alveolar concentration, 3%, 2 l/min, 8 h) and thereby exposed to compound A. Urine was collected at 24-h intervals for 72 h after anesthesia. Rats, which served as a positive control, were given compound A intraperitoneally, and urine was collected for 24 h afterward. Human and rat urine samples were analyzed by19 F nuclear magnetic resonance spectroscopy and gas chromatography-mass spectrometry for the presence of compound A metabolites.

Results: Analysis of human and rat urine showed the presence of the compound A metabolites [S-[2-(fluoromethoxy)-1,1,3,3,3-pentafluoropropyl]-N-acetyl-L-cysteine, (E)- and (Z)-S-[2-(fluoromethoxy)-1,3,3,3-tetrafluoro-1-propenyl]-N-acetyl-L-cyst eine, 2-(fluoromethoxy)-3,3,3-trifluoropropanoic acid, 3,3,3-trifluorolactic acid, and inorganic fluoride. The presence of 2-(fluoromethoxy)-3,3,3-trifluoropropanoic acid and 3,3,3-trifluorolactic acid in human urine was confirmed by gas chromatography-mass spectrometry.  相似文献   

36.
We performed a longitudinal analysis of serum interleukin-2 (IL-2) and soluble IL-2 (sIL-2R) concentrations in 60 patients with relapsing-remitting (R-R) multiple sclerosis (MS) as well as in 33 age- and sex-matched normal controls. Overall, we found that serum IL-2 levels remained low (less than 10 U/ml) and did not change appreciably over time; however, marked fluctuations in sIL-2R levels were observed in both the patient and control groups. Using patients as their own controls, we calculated an interrelapse (disease stable) mean sIL-2R concentration as a baseline for comparison with relapse values; sIL-2R levels greater than the 90th percentile of the Student's t distribution of stable values were defined as "peaks." There were a total of 27 sIL-2R peaks, eight (30%) of which correlated with clinical relapses but were potentially predictive of only 18% (8/45) of all the recorded clinical relapses. There was no difference in disease severity (Expanded Disability Status Scale) score between peak-correlated and noncorrelated relapses. Our data suggest that despite reports of elevated levels of IL-2 and sIL-2R in MS, neither may be a useful marker for predicting clinical disease activity in R-R MS.  相似文献   
37.
The search for ways to mitigate the effects of family breakdown on parents and children includes legislative and clinical efforts which to some extent influence each other. In the past year much public interest has been aroused in Canada, and particularly in Ontario, in the issue of legislative changes which would make joint custody the usual or "preferred" legal disposition of custody cases. This paper provides a discussion of the legislated preference, or "rebutable presumption" of joint custody from a historical, legal and clinical point of view. Definition and elaboration of what joint custody is from the legal and practical perspectives is provided with an emphasis on Canadian laws and practice. The legal rights of the non-custodial parent are explained, and relevant case law is highlighted. The relationship between joint custody, support orders and relitigation rates are elaborated. Following this is a critical overview of the empirical research on joint custody as it relates to the adjustment of children and parent satisfaction is included. It is concluded that while there is little question that shared parenting can be beneficial to children, the enthusiasm of legislators for joint custody has not been supported by empirical data. It is necessary to examine under what circumstances and for which kinds of parents and children joint custody might be beneficial since it is unlikely that one solution will fit the needs of all families and all stages of family life.  相似文献   
38.
The dominant cone-rod dystrophy gene CORD6 has previously been mapped to within an 8 cM interval on chromosome 17p12-p13. The retinal- specific guanylate cyclase gene (RETGC-1), which maps to within this genetic interval and previously was implicated in Leber's congenital amaurosis, was screened for mutations within this family and in a panel of small families and individuals with various cone and cone- rod dystrophy phenotypes. A missense mutation (E837D) was identified in affected members of the CORD6 family, as well as a second missense mutation (R838C) in three other families with dominant cone-rod dystrophy. RETGC-1 is only the fourth gene to be implicated in cone-rod dystrophy and this is the first report of dominant mutations in this gene.   相似文献   
39.
40.
1. Grating contrast sensitivities have been determined over a range of spatial frequencies for a normal subject and for subjects who are visually biased in that they have a lower resolution capacity for targets of specific orientations. The bias si only found in astigmatic subjects and the grating orientation yielding poorest acuity coincides with the most defocused astigmatic meridian. However this resolution anisotropy remains when optical factors are accounted for. 2. For the normal subject, high and low frequency attenuation is found and a typical reduction in contrast sensitivity is exhibited for oblique target orientations. 3. The biased subjects, called meridional amblyopes because they have reduced acuity for a given grating orientation, show markedly abnormal contrast sensitivity functions. Their cut-off spatial frequencies are different for various target orientations and this difference applies also to contrast sensitivity over nearly the entire spatial frequency range tested (0-5-16 cycles/deg). The differences are of about the same magnitude for most frequencies and they are found in all types of meridional amblyopes. 4. Optical explanations of these differences are ruled out by laser-interference fringe tests and by varying effective pupil size. 5. Theoretical effects of defocus have been calculated to compare predicted visual deprivation with performance. Results indicate that reduced contrast sensitivity functions can be equivalent to a small defocus effect. 6. To examine the results in the spatial domain, inverse Fourier transforms of representative contrast sensitivity functions have been computed. The optical portion of the resulting spatial weighting functions has been parcelled out to obtain neural spatial weighting functions.  相似文献   
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