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91.
Environmental exposure has been linked to non-Hodgkin's lymphoma (NHL). Toxic volatile compounds were found in groundwater downstream of an industrial site in southern Israel. The risk of NHL and clinical characteristics of NHL patients were analyzed in relation to their proximity to the site.  相似文献   
92.
OBJECTIVE: It is widely held that there is a delayed onset of antipsychotic action and that any early effects represent nonspecific behavioral effects. Recent research has shown that antipsychotic action begins within the first week. The authors tested the hypothesis that psychosis improves within the first 24 hours of antipsychotic treatment. METHOD: In this multicenter, double-blind, placebo-controlled study, 311 patients with a diagnosis of schizophrenia spectrum disorder and an acute exacerbation were randomly assigned to receive 10 mg i.m. of olanzapine, 7.5 mg i.m. of haloperidol, or intramuscular placebo. Subjects were rated with structured rating scales (Positive and Negative Syndrome Scale and Clinical Global Impression) at baseline, 2 hours, and 24 hours. RESULTS: The olanzapine and haloperidol groups showed greater resolution of overall symptoms than the placebo group; for the olanzapine group, this effect was evident at 2 hours. A factor analysis showed that an independent change in psychosis (which included conceptual disorganization, hallucinatory behavior, unusual thought content) was evident within the first 24 hours for both drugs. This improvement in core psychosis was not mediated unidirectionally by changes in nonspecific behavioral effects or other psychopathology. CONCLUSIONS: These data suggest that the onset of antipsychotic action is early and that the magnitude of this action grows with time. This clinical reality calls into question some prevailing hypotheses regarding the mechanism of action of antipsychotics and suggests that antipsychotic action may be more proximally related to the blockade of dopamine transmission than was originally thought.  相似文献   
93.
BACKGROUND AND PURPOSE: Low molecular weight antioxidants (LMWA), which reflect tissue reducing power, are among the endogenous mechanisms for neutralizing reactive oxygen species (ROS). Ischemic preconditioning (IPC) was associated with decreased oxidative stress. We examined the effect of focal ischemia on LMWA and on prostaglandin E(2) (PGE(2), a product of arachidonic acid oxidation) in the brain, heart, liver, and lungs of rats subjected to 90 min of ischemia and in IPC rats subjected to similar insult. METHODS: Transient right middle cerebral artery occlusion (MCAO) was performed for 90 min and at 0, 5, 30, 60, or 240 min of reperfusion, LMWA and PGE(2) were evaluated by cyclic voltametry (CV) and radioimmunoassay, respectively. IPC was induced by 2 min of MCAO, 24 h prior to the major ischemic episode. RESULTS: LMWA decreased at 5 min of reperfusion in the brain, heart, liver, and lung and rose 4 h later only in the brain. PGE(2) levels increased three to fivefold in all tissues examined. Surprisingly, in IPC rats a dramatic increase of LMWA occurred at 5 min of reperfusion in the brain and in the peripheral organs. Uric acid, but not ascorbic, is the major LMWA increased. CONCLUSIONS: We propose that after ischemia, ROS rapidly consume the antioxidants reserves in the brain and also in peripheral organs, suggesting that the whole body is under oxidative stress. Moreover, part of the neuroprotection afforded by IPC is mediated by the brain's ability to mobilize antioxidants, especially uric acid, that attenuate the massive ROS-mediated oxidative stress.  相似文献   
94.
OBJECTIVE: This study was conducted to examine the relation between iron status and neurobehavioral development in premature infants. STUDY DESIGN: Infants born before 34 weeks postmenstrual age and who were medically stable were studied. Anemia was defined as hemoglobin < or =10 g/Dl and low iron stores as a serum ferritin concentration < or =75 microg/l. The infants were classified as anemic with low ferritin (Group 1; n=18), anemic with normal ferritin (Group 2; n=14), and nonanemic with normal ferritin (Group 3; n=21). A total of 18 reflexes were behaviorally evaluated at 37 weeks postmenstrual age and "reflex scores" were compared between the groups. Higher scores reflect a greater percentage of abnormal reflexes. RESULTS: Infants in group 1 (anemia/low ferritin) had a significantly higher reflex score (51.45+/-18.32%) than infants in Group 3 (38.32+/-17.75%). Group 2 had an intermediate score (45.40+/-21.70%), but not different from the other two groups. CONCLUSION: These data indicate that low iron status, both measured by anemia and ferritin levels, is related to poorer neurobehavioral status in premature infants.  相似文献   
95.
96.
Amir O  Kishon-Rabin L 《The Laryngoscope》2004,114(6):1021-1026
OBJECTIVES/HYPOTHESIS: The objective was to extend our knowledge of the effect of birth control pills on voice quality in women based on various acoustic measures. STUDY DESIGN: A longitudinal comparative study of 14 healthy young women over a 36- to 45-day period. METHODS: Voices of seven women who used birth control pills and seven women who did not were recorded repeatedly approximately 20 times. Voice samples were analyzed acoustically, using an extended set of frequency perturbation parameters (jitter, relative average perturbation, pitch period perturbation quotient), amplitude perturbation parameters (shimmer, amplitude average perturbation quotient), and noise indices (noise-to-harmonics ratio, voice turbulence index). RESULTS: Voice quality and stability were found to be better among the women who used birth control pills. Lower values were found for all acoustic measures with the exception of voice turbulence index. Results also provided preliminary indication for vocal changes associated with the days preceding ovulation. CONCLUSION: In contrast to the traditional view of oral contraceptives as a risk factor for voice quality, and in keeping with the authors' previous work, the data in the present study showed that not only did oral contraceptives have no adverse effect on voice quality but, in effect, most acoustic measures showed improved voice quality among women who used the birth control pill. The differences in the noise indices between groups may also shed light on the nature of the effect of sex hormones on vocal fold activity. It was suggested that hormonal fluctuations may have more of an effect on vocal fold regulation of vibration than on glottal adduction.  相似文献   
97.
PURPOSE OF REVIEW: Sex hormone fluctuations were shown to affect female vocal folds and laryngeal function. Laryngeal changes are evident throughout the span of life, starting at puberty with the arousal of the hormonal system, fluctuating systematically during the reproductive years with the menstrual cycle, and then changing again with the decline of hormonal activity at menopause. This paper reviews recent developments in this field. RECENT FINDINGS: Early studies that explored this relation were based merely on subjective impressions of voice quality, recent studies have used more objective tools for examining this relation, including histologic observations, stroboscope, electroglottography (EGG), and computerized acoustic analyses. In these studies, the larynx was shown to be a hormonal target organ and, as such, sex hormones affect its morphology, histology, and function, similar to their effect on the genitals and other organs. SUMMARY: Examining the relation between sex hormones and the larynx could assist in understanding the mechanisms of voice production, and it could provide the clinician with supplemental diagnostic information on different medical conditions.  相似文献   
98.
BACKGROUND: The incidence of ovarian metastasis in women with clinical stage I endometrial carcinoma is generally reported to be 5%, leading to the practice of removing the ovaries at surgery even in young patients. METHODS: A retrospective study of 84 patients with clinical stage I endometrial cancer was carried out. Patients were excluded if the pathologic study revealed any evidence of extrauterine, apart from adnexal, spread or if the peritoneal cytology was positive. Patients with serous papillary or clear cell tumor histology were also excluded. RESULTS: Sixty-seven patients fulfilled the inclusion criteria. Only three (4%) patients were found to be in surgical stage IIIA, all three had grade 3 tumors. Of these patients, two had uterine serosal involvement and one had a microscopic tumor implant in a fallopian tube; none had ovarian metastasis. CONCLUSIONS: The risk of ovarian metastasis in women with well to moderately differentiated endometrial cancer, myometrial invasion limited to less than one half of the myometrium, negative peritoneal cytology and no evidence of metastatic lymph node spread is negligible. Young patients with a preoperative histological diagnosis of well to moderately differentiated endometrial carcinoma may be surgically staged, leaving the final decision regarding removal of the ovaries pending a thorough pathological review of the surgical specimens.  相似文献   
99.
To determine the extent to which electrophysiologic tests of the afferent visual pathway are affected by vitrectomy, the procedure was performed in 15 eyes of 11 adult Dutch-belted rabbits. An electroretinogram (ERG), visually evoked cortical potential (VECP), and electrically evoked cortical potential (EECP) were obtained preoperatively and sequentially after surgery. For electrical stimulations, biphasic impulses were delivered to the retina. Post-vitrectomy declines of 49, 25, and 41% from the median baseline amplitudes and increases of 13, 18, and 17% from the median baseline latency values were found for ERG, VECP, and EECP, respectively. At 90 min, 13 to 30% of eyes still had an amplitude more than 10% below baseline on at least one of the three tests, whereas 10 to 47% of eyes had an abnormal latency more than 10% above baseline on at least one of the three tests. Amplitudes were more likely than latencies to return to near baseline, but for eyes that remained subnormal, the decline was greater for amplitudes than latencies. Significant alterations in retinal function, manifested by declines in amplitudes and increases in latencies of the ERG, VECP, and EECP, persist in a large proportion of eyes up to 90 min post-vitrectomy.  相似文献   
100.
BACKGROUND: Apoptosis (i.e., programmed cell death) plays a major role in the development of astrocytic tumors, which are the most common tumors of the central nervous system. ARTS, a proapoptotic protein that is localized in the mitochondria, promotes apoptosis by functioning as an XIAP antagonist and a caspase activator. METHODS: To investigate the role of ARTS in astrocytoma, the authors examined protein expression and apoptotic activity in 72 astrocytic tumors, which included low-grade astrocytomas, anaplastic astrocytomas, and glioblastomas. RESULTS: Whereas normal astrocytes did not express the ARTS protein, astrocytoma cells strongly expressed ARTS, and the expression of this protein increased with increasing tumor grade. Furthermore, increased levels of ARTS were significantly associated with higher rates of apoptosis (as measured using the terminal deoxynucleotidyltransferase-mediated deoxyuridine triphosphate nick end-labeling [TUNEL] assay as well as an immunohistochemical staining assay for active caspase-3) in these tumors. Levels of two other apoptosis-related proteins, p53 and Bcl-2, also were examined using immunohistochemical methods; ARTS expression was found to be positively correlated with expression of the former and negatively correlated with expression of the latter, which is known to possess antiapoptotic activity. CONCLUSIONS: The results of the current study suggest that ARTS levels reliably reflect the ability of cells to undergo apoptosis, which serves as a defense mechanism against the development and progression of astrocytoma. Furthermore, ARTS expression, when taken into consideration in combination with tumor grade, was the only independent predictor of survival identified in the current analysis. Thus, the authors conclude that ARTS may possess utility as a prognostic marker, as well as a therapeutic tool, for patients with astrocytoma.  相似文献   
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