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991.
Children with cerebral palsy associated with periventricular leukomalacia frequently develop unprovoked epileptic seizures. This article reports an analysis of risk factors for epilepsy in children with radiologically confirmed periventricular leukomalacia. This cohort was screened for epilepsy and for an array of clinical and demographic factors. Of 154 subjects with radiologically confirmed periventricular leukomalacia, 40 (26.0%) had epilepsy. In the epileptic group, radiologic pathology other than periventricular leukomalacia was uncommon. Significant associations were found between epilepsy and cerebral palsy patterns other than spastic diparesis, mental handicap, cortical visual impairment, neonatal seizures, and severe periventricular leukomalacia. Only the presence of neonatal seizures was significantly associated with epilepsy once other risk factors were controlled in the regression model. Some previous studies have shown an association between neonatal seizures and later epilepsy for cerebral palsy in general. This is the first report of such an association for a single predominant type of cerebral pathology.  相似文献   
992.
Papillary carcinoma, a rare malignant tumor of the breast, accounts for only 1–2% of breast tumors. It predominantly affects elderly women in the sixth decade to the eighth decade of life. The incidence of bilateral papillary carcinomas is very low, with only one case reported in the literature. However, there has been no report of a case of bilateral invasive papillary carcinoma. A case of bilateral invasive papillary carcinoma of the breasts, along with mammography and ultrasound findings, is reported here.  相似文献   
993.
BACKGROUND: The aim of this study was to evaluate the characteristic features of the mechanical responses and membrane potential changes induced by remifentanil in human umbilical arteries (HUAs). The ionic mechanisms underlying the electrophysiological responses were pharmacologically assessed using two K(+) channel blockers. METHODS: Thirty-eight HUAs were obtained. Contraction-relaxation, membrane potential changes and electrical responses of the HUAs were recorded. RESULTS: Remifentanil produced concentration-dependent relaxation in both endothelium-intact and endothelium-denuded HUA rings. Remifentanil produced a significantly greater relaxation response in intact than in denuded HUA rings. In endothelium-intact rings, pre-treatment with L-nitroarginine [N(w)-NITRO-(L)-ARGININE (L-NO-ARG)] or indomethacin decreased the degree of remifentanil-induced relaxation. Remifentanil (10(-9)-10(-6) mol/l) produced a transient concentration-dependent membrane hyperpolarization, which was not decreased by pre-treatment with L-NO-ARG or indomethacin. It also produced a small concentration-dependent hyperpolarization in the presence of charybdotoxin or tetraethylammonium. CONCLUSION: In both endothelium-intact and endothelium-denuded HUAs, remifentanil induces concentration-dependent vasorelaxation and simultaneously releases nitric oxide, prostaglandins and possibly an endothelium-derived hyperpolarizing factor. In addition, it produces hyperpolarization in a dose-dependent manner. Hyperpolarization induced by remifentanil involves the activation of Ca(2+)-dependent and Ca(2+)-independent potassium channels regulated by intracellular Ca(2+).  相似文献   
994.
Tularemia is a zoonotic disease caused by Francisella tularensis. Francisella tularensis is transmitted to humans by direct contact or ingestion of infected animal tissues, through the bite of infected arthropods, by consumption of contaminated food or water, or from inhalation of aerolized bacteria. In this report we describe 2 cases with oropharyngeal tularemia who presented with tonsillopharyngitis and cervical lymphadenitis.  相似文献   
995.

Background

Higher exposure to outdoor air pollution is associated with increased cardiopulmonary deaths, but there is limited evidence about the association between outdoor air pollution and diagnosed cardiovascular disease. Our study aimed to estimate the size of the association between long term exposure to outdoor air pollution and prevalent cardiovascular disease.

Methods

We carried out a cross-sectional analysis of data on more than 19,000 white adults aged 45 and older who participated in three representative surveys of the English population in 1994, 1998 and 2003, examining the relationship between self-reported doctor-diagnosed cardiovascular disease and exposure to outdoor air pollutants using multilevel regression techniques and meta-analysis.

Results

The combined estimates suggested that an increase of 1 μg m-3 in concentration of particulate matter less than 10 microns in diameter was associated with an increase of 2.9% (95% CI -0.6% to 6.5%) in prevalence of cardiovascular disease in men, and an increase of 1.6% (95%CI -2.1% to 5.5%) in women. The year-specific analyses showed strongly positive associations in 2003 between odds of cardiovascular disease in both men and women and exposure to particulate matter but not in 1994 or 1998. We found no consistent associations between exposure to gaseous air pollutants and doctor-diagnosed cardiovascular disease.

Conclusion

The associations of prevalent cardiovascular disease with concentration of particulate matter less than 10 microns in diameter, while only weakly positive, were consistent with the effects reported in cohort studies. The results provide evidence of the size of the association between particulate air pollution and the prevalence of cardiovascular disease but no evidence for an association with gaseous pollutants. We found strongly positive associations between particulate matter and cardiovascular disease in 2003 only, which highlights the importance of replicating findings in more than one population.  相似文献   
996.
997.
Aim: To determine whether two episodes of acute urinary retention lead to additional ischemia-reperfusion injury due to decompression of the bladder, or not. Materials and methods: Sham, retention and recurrent retention groups consisting of 5, 8 and 8 Wistar Albino male rats were randomized, respectively. After the bladders of rats were emptied with 3F catheter, penile urethras were clamped with aneurism clamp and waited for 30 min after diuresis was forced. At the end of this period, penile clamps were removed and the bladder was again decompressed with 3F catheter and after 30 min removed for examination. In the recurrent retention group, the same process was repeated after an interval of one week. Malonedialdehyde (MDA) levels, indicator of lipid peroxidation and myeloperoxidase (MPO) levels, indicator of leukocyte activation, were examined biochemically in the tissues of the removed bladders. Results: In the retention and recurrent retention groups, the average increase in bladder MDA and MPO values was higher than the values of sham group (P < 0.05), however, no significant difference was determined between retention and recurrent retention groups (P > 0.05). Conclusion: In the bladder tissue, due to acute urinary retention and following decompression process, ischemia-reperfusion injury occurs. Two episodes of acute urinary retention do not lead to additional the ischemia-reperfusion injury that develops in the bladder.  相似文献   
998.
Centaurea species are used for the treatment of various ailments in the popular medicine in some countries. This study was designed to examine antioxidant potentials and fatty acid profiles of five Centaurea species from Turkey flora. Antioxidant properties of methanolic extracts from these species were evaluated by six different methods: phosphomolybdenum assay, free radical scavenging assay, β-carotene/linoleic acid test system, metal chelating activity, ferric and cupric reducing power. Total phenolic and flavonoid concentrations of each extract were also determined using the Folin–Ciocalteu reagent and aluminum chloride. The results of these assay showed a significant antioxidant capacity in all researched extracts. Centaurea cheirolopha extract, with the highest amount of total phenolic and flavonoids, showed the highest antioxidant activities in all assay, except for metal chelating. Fatty acid profiles of these species were examined by GC–FID and 30 fatty acids were identified. Palmitic, linoleic, oleic, and linolenic acid were detected as the main components. The results of the study indicated that the Centaurea species can be considered as a source of new natural antioxidants and unsaturated fatty acids for food, cosmetic and pharmaceutical industries.  相似文献   
999.
OBJECTIVE: The principal aim of this study was to assess the current prevalence rate of panic disorder (PD) in pregnant women during the third trimester of pregnancy. The second aim of the present study was to investigate the clinical characteristics of PD in pregnant and nonpregnant women. METHOD: The study data were gathered from 512 consecutive women in the third trimester of pregnancy who were admitted to the obstetric outpatient clinics of 2 university research centers. The diagnosis of PD was determined by means of the Structured Clinical Interview for Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition Axis I disorders in the third trimester of pregnancy. Within the same period, the Panic and Agoraphobia Scale was used to determine the severity of PD. In addition, we compared the clinical characteristics of PD in gravid subjects (n = 13) with their control group. A control group was composed of 19 consecutive nonpregnant female outpatients diagnosed with PD who presented to the psychiatric outpatient clinics of the same hospitals. RESULTS: The prevalence rate of PD was found to be 2.5% (n = 13) among the subjects in the third trimester of pregnancy. Of these 13 pregnant, 7 subjects reported that PD developed during the 6th to 28th weeks of their gestation, and the number of subjects who experienced PD symptoms before pregnancy was 6. In addition, there was no statistically difference between gravid and nongravid PD cases with regard to the severity of panic symptoms. CONCLUSION: Our study suggests that PD may be common among pregnant females during the third trimester of pregnancy and seems to be associated with similar clinical features during gestation and nongestation.  相似文献   
1000.
The ErbB2 receptor is a proto-oncogene associated with a poor prognosis in breast cancer. Trastuzumab, a humanized anti-ErbB2 antibody currently in clinical use, has proven to be an essential tool in the immunotherapy of breast carcinoma. Additionally, ErbB2 is involved in the growth and survival pathway of adult cardiomyocytes which accounts for the trastuzumab-induced cardiotoxicity. Moreover, in metastatic breast cancer patients treated with trastuzumab, endomyocardial biopsy documented focal vacuolar changes, pleomorphic mitochondria, myocardial cell hypertrophy, and mild interstitial fibrosis on electron microscopy without accompanying light microscopic abnormalities, a finding consistent with a reversible pattern of cardiac injury. On the other hand, aldosterone and mineralocorticoid receptor (MR) researches have experienced a revival after the discovery that aldosterone and MR are not only involved in the electrolyte and volume balance but also in the pathophysiological processes of the reno-cardiovascular system. Aldosterone has both genomic and nongenotropic effects on epidermal growth factor receptor (EGFR) expression. Genomic effect induces genomic up-regulation of the EGFR protein expression via EGFR promoter, whereas nongenotropic effect leads to the EGFR transactivation resulting in persistent pathophysiological effects including formation of extracellular matrix and myocardial hypertrophy. Spironolactone, an aldosterone receptor antagonist, is known to ameliorate the cardiac damage. The underlying mechanism for the genomic interactions seem to be the stimulation of the EGFR promoter by aldosterone-bound MR, which then dose-dependently enhances the EGFR protein levels, which may be successively inhibited by spironolactone. By the light of these findings, we hypothesize that spironolactone may ameliorate trastuzumab-induced cardiotoxicity via inhibition of transactivation of the EGFR by aldosterone and reversing myocardial hypertrophy. This issue warrants further studies.  相似文献   
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