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81.
JJ Lu CL Perng RY Shyu CH Chen Q Lou SK Chong CH Lee 《Canadian Metallurgical Quarterly》1999,37(3):772-774
Five different PCR methods for the detection of Helicobacter pylori were evaluated. The results of this study indicate that of the five PCR methods examined, the ureC (glmM) gene PCR is the most sensitive and specific for the detection of H. pylori in gastric biopsy specimens. 相似文献
82.
RY Liu JN Zhou J van Heerikhuize MA Hofman DF Swaab 《Canadian Metallurgical Quarterly》1999,84(1):323-327
Sleep disruption, nightly restlessness, sundowning, and other circadian disturbances are frequently seen in Alzheimer's disease (AD) patients. Changes in the suprachiasmatic nucleus and pineal gland are thought to be the biological basis for these behavioral disturbances. Melatonin is the main endocrine message for circadian rhythmicity from the pineal. To determine whether melatonin production was affected in AD, melatonin levels were determined in the cerebrospinal fluid (CSF) of 85 patients with AD (mean age, 75 +/- 1.1 yr) and in 82 age-matched controls (mean age, 76 +/- 1.4 yr). Ventricular postmortem CSF was collected from clinically and neuropathologically well defined AD patients and from control subjects without primary neurological or psychiatric disease. In old control subjects (>80 yr of age), CSF melatonin levels were half of those in control subjects of 41-80 yr of age [176 +/- 58 (n = 29) and 330 +/- 66 (n = 53) pg/mL, respectively; P = 0.016]. We did not find a diurnal rhythm in CSF melatonin levels in control subjects. In AD patients the CSF melatonin levels were only one fifth (55 +/- 7 pg/mL) of those in control subjects (273 +/- 47 pg/mL; P = 0.0001). There was no difference in the CSF melatonin levels between the presenile (42 +/- 11 pg/mL; n = 21) and the senile (59 +/- 8 pg/mL; n = 64; P = 0.35) AD patients. The melatonin level in AD patients expressing apolipoprotein E-epsilon3/4 (71 +/- 11 pg/mL) was significantly higher than that in patients expressing apolipoprotein E-epsilon4/4 (32 +/- 8 pg/ml; P = 0.02). In the AD patients no significant correlation was observed between age of onset or duration of AD and CSF melatonin levels. In the present study, a dramatic decrease in the CSF melatonin levels was found in old control subjects and even more so in AD patients. Whether supplementation of melatonin may indeed improve behavioral disturbances in AD patients should be investigated. 相似文献
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Although it is well documented that child maltreatment exerts a deleterious impact on child adaptation, much less is known about the precise etiological pathways that eventuate in child abuse and neglect. This paper reports on a multimethod ecological study of the relationship between neighborhood structural factors and child maltreatment reports in African American and European American census tracts. The study had two major components. First, in an aggregate analysis, the effects of four measures of community structure (impoverishment, child care burden, instability, and geographic isolation) on child maltreatment report rates were examined separately for predominantly African American (n = 94) and predominantly European American (n = 189) census tracts. Impoverishment in particular had a significantly weaker effect on maltreatment rates in African American than in European American neighborhoods. Second, focused ethnographies were conducted in four selected census tracts with child maltreatment report rates in the highest and lowest quartiles. Ethnographic data point to the importance of the social fabric in accounting for differences in child maltreatment report rates by predominant neighborhood ethnicity. 相似文献
85.
Vocal fold palsy is a cause of dysphonia. Due to incomplete glottic closure during phonation, patients with a unilateral vocal fold palsy present with a weak and breathy voice and recurrent aspiration. To lessen the clinical manifestations of unilateral vocal fold palsy, polytetrafluoroethylene (Teflon) paste is one agent which has been injected into the paraglottic region, thus causing the vocal fold to move more medially. One of the complications associated with Teflon paste injection is migration of the paste into the surrounding tissues. We present a patient with idiopathic left vocal fold palsy who underwent Teflon injection to the vocal fold and subsequently developed a precricoid nodule, mimicking a cartilaginous swelling. 相似文献
86.
RY Singh 《Canadian Metallurgical Quarterly》1993,41(4):188-189
Thyroid peroxidase (TPO), the enzyme responsible for thyroid hormone synthesis, is a key autoantigen in autoimmune thyroid disease. Based on the results of a study using both isotopic and nonisotopic in situ hybridization, we assign the gene coding for human TPO to chromosome region 2p25-->p24. 相似文献
87.
A new triterpenoid, squasapogenol (S-11), was isolated from the hydrolytic products of dilute ethanol (10%) extract of the roots of Glycyrrhiza squamulosa Franch, along with four known triterpenoids. The structure of S-11 was elucidated as olean-11,13(18)-diene-3 beta, 22 beta-diol on the basis of chemical and spectroscopic data. The four known compounds were identified as betulinic acid(S-8), methyl ester of macedonic acid(S-9), soyasapogenol B (S-10) and olean-13(18)-ene-22 alpha-Cl-3 beta, 24-diol(S-12). 相似文献
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