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171.
Hypoxic-ischemic encephalopathy (HIE) is a major cause of neonatal morbidity and mortality. Electroencephalography (EEG) and brain magnetic resonance imaging (MRI) are frequently performed in these infants, but the prognostic value of the combined use of EEG and MRI needs additional exploration. The purpose of this study was to investigate, in neonates with HIE, the role of early EEG and conventional MRI in the prediction of infants at risk for persistent encephalopathy at 18 months of age. Thirty-four term infants with HIE were enrolled in this prospective study. EEG was recorded within the first 72 hours after birth and a brain MRI scan was done between 1 and 4 weeks of age. Denver Developmental Screening Test II was performed at 6, 12, and 18 months of age. Three infants (9%) had mild HIE, 21 infants (62%) had moderate HIE, and 10 infants (29%) had severe HIE. The EEG background was normal, moderately, severely, and extremely discontinuous in eight (24%), three (9%), sixteen (47%), and seven (20%) neonates, respectively. EEG background activities correlated significantly with HIE severity (p = 0.0001). MRI findings significantly correlated with EEG background (p = 0.001). Normal MRI scans and minimal basal ganglia lesions were always associated with normal EEG background. Patients with severe basal ganglia and thalamic lesions in MRI (n = 2) had extreme discontinuous EEG background. For the prediction of poor outcomes, abnormal EEG background activity had a sensitivity (Sn) = 100%, a specificity (Sp) = 100%, positive predictive value (PPV) = 100%, and negative predictive value (NPV) = 100%, whereas values of abnormal MRI scans were Sn of 100%, Sp = 43%, PPV = 82%, and NPV=100%. EEG background activity is the best element to predict abnormal outcomes. Severe basal ganglia and thalamic injuries on MRI scans are associated with poor outcomes. Otherwise, MRI does not contribute to the prediction of outcomes at 18 months of age.  相似文献   
172.
STUDY OBJECTIVE: The presence of fimbrial pathology in advanced endometriosis is clearly understood. However, little is known about the prevalence of fimbrial pathology in early stages of endometriosis. The purpose of this study is to determine the prevalence of fimbrial pathology in patients with infertility with early stages of endometriosis. DESIGN: Historical cohort study (Canadian Task Force classification II/III). SETTING: Tertiary referral center. PATIENTS: The study group (Group 1) consisted of 315 infertile women who were found to have stage I or stage II endometriosis, and the control group (Group 2) consisted of 152 infertile women without endometriosis (Group 2). INTERVENTION: Laparoscopic evaluation for the presence and type of fimbrial pathology. MEASUREMENTS AND MAIN RESULTS: The prevalence of fimbrial pathology was significantly higher in infertile patients with early stages of endometriosis (50.2%) compared with infertile patients with no endometriosis (17.8%, p <.0001). CONCLUSION: These preliminary data suggest the presence of fimbrial pathology in many patients with early stages of endometriosis. Such pathology may act as a mechanical factor interfering with the ovum pick-up mechanism.  相似文献   
173.
174.
Bio-based silica, lignocellulose, and activated carbon were simply produced via the recycling of Hassawi rice biomass waste of Al-Ahsa governorate in the eastern Saudi Arabia region using a fast chemical treatment procedure. Rice husk and rice straw wastes were collected, ground, and chemically treated with sodium hydroxide to extract silica/silicate from the dried plant tissues. The liquid extract is then treated with acid solutions in order to precipitate silica/silicate at neutral medium. Lowering the pH of the supernatant to 2 resulted in the precipitation of lignocellulose. Thermal treatment of the biomass residue under N2 gas stream resulted in activated carbon production. Separated products were dried/treated and characterized using several physical examination techniques, such as FT-IR, SEM/EDX, XRD, and Raman spectroscopy in order to study their structure and morphology. Silica and lignocelluloses products were then preliminarily used in the treatment of wastewaters and water-desalination processes.  相似文献   
175.
HIV continues to affect African American populations in the United States at disproportionate levels. Recent reports have described potentially high-risk behaviors of African American men who identify as heterosexual but who engage in secretive sex with other men. These men have been referred to as being “on the Down Low,” and this terminology has been used to label subgroups of African American men and explain sexual risks for HIV infection in the African American community. In this paper, we argue that an uncritical use of this terminology for guiding public health and HIV prevention strategies can be problematic and counterproductive because it (a) stigmatizes and exoticizes secretive same-sex sexuality as a unique issue among African American men, and (b) ignores the social conditions under which HIV transmission occurs. We explore some historical roots contributing to current perspectives on African American men's sexuality, describe the use of the term “on the Down Low” and its application to same-sex behavior among African American men, and explain how this term can both clarify and potentially ambiguate efforts to address HIV risk among African American men. Recommendations for research and HIV prevention strategies are also provided.  相似文献   
176.
This work describes the preparation of an analytical microextraction sorbent using a simple and versatile sol–gel hybrid composite, i.e., aramid oligomers wrapping multi-walled carbon nanotubes (CNTs) covalently bonded to a porous silica network. To overcome the inherent shortcomings of the CNTs'' solubility and dispersion in both organic phases and in the sol–gel solution, the outer surface of the CNTs was initially functionalized with carboxylic acid groups and then reacted with both aramid oligomers and 3-aminopropyl triethoxysilane (APTES). The obtained sorbent was characterized by FT-IR, scanning electron microscopy (SEM), and thermogravimetric analysis (TGA). Using sol–gel chemistry, the functionalized CNTs were coated onto SPME fibers and used in conjunction with GC-MS for the analysis of polycyclic aromatic hydrocarbons (PAHs) in water and soil samples. Excellent repeatability (run-to-run RSD% ∼ 8) and reproducibility (fiber-to-fiber RSD% ∼ 6) were achieved in addition to low LODs (0.10–0.30 ng mL−1) and noticeable recovery%. The present method of sorbent preparation led to enhanced thermal and chemical stabilities, a long sorbent lifetime and good affinity towards PAHs. Moreover, the present sorbent enhanced the extraction capability by more than 30% compared to that of commercially available PDMS counterparts.

This work describes the preparation of an analytical microextraction sorbent using a simple and versatile sol–gel hybrid composite, i.e., aramid oligomers wrapping multi-walled carbon nanotubes (CNTs) covalently bonded to a porous silica network.  相似文献   
177.
Moyamoya disease is an unusual occlusive cerebrovascular condition commonly seen in children, marked by stenosis of the internal carotid artery and circle of Willis, causing, cerebral ischemia. Moyamoya syndrome is a Moyamoya-like arteriopathy with risk factors including autoimmune disorders, thyroid disease, sickle cell disease, or Down syndrome. Trisomy 21 is a genetic disorder consistent with specific physical and behavioral characteristics, with intellectual impairment. We describe a rare case of Moyamoya syndrome manifesting as ischemic stroke in an adult with Down syndrome  相似文献   
178.
A series of statistically‐based models have been developed for predicting the formation of individual trihalomethane (THM) species, ranging from chloroform to bromoform, as a function of various reaction conditions. These equations allow a quantitative assessment of bromide effects on overall THM formation as well as THM speciation.  相似文献   
179.
1背景由马来西亚卫生部和马来西亚国民大学(UKM)联合承担的研究项目,主要研究者是Dr·Syed Mohamed AI Junid,研究中心是吉隆坡总医院(GHKL)儿童研究所、UKM医院儿科病房及乌鲁冷岳区(Hulu Langat)医疗中心,研究时间自2004年1月~2006年6月。研究开始前分别获得了马来西亚卫生部  相似文献   
180.
The influence of a single dose of aspirin on the pharmacokinetics of the synthetic progestogen norethindrone was studied in rabbits. It was found that neither the 24-hr plasma levels nor the pharmacokinetic parameters of norethindrone following intravenous dosing were significantly altered by aspirin. However, after oral administration of norethindrone, the area under the plasma norethindrone versus time curve was significantly decreased by aspirin from 0.72 ± 0.058 ng/ml × hr to 0.49 ± 0.046 ng/ml × hr (mean ± S.E) and the oral bioavailability was reduced from 56 ± 4.2% to 38 ± 3.6%, perhaps due to increased gut wall metabolism of norethindrone by aspirin.  相似文献   
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