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81.
82.
This paper describes a novel LOCOS (LOCal Oxidation of Silicon) technology that uses nitrogen in-situ doped amorphous-Si as a buffer layer instead of the undoped poly-Si used in conventional Poly Buffered LOCOS (PBL). This technology makes it possible to use a thin 6-nm pad oxide by preventing the formation of voids in Si buffer layer and improves edge morphology and effective dimension loss. Therefore, the technology will be used in advanced LSI fabrication with KrF lithography, notwithstanding that the number of processing steps is the same as conventional PBL. This new LOCOS technology is the most promising isolation technology for the deep-submicron era due to its simplicity and scalability  相似文献   
83.
An autopsy case of Sj?gren-Larsson syndrome (SLS), an 8-year-old boy, is presented with neuropathological investigations. Widespread deposition of 2 different types of unusual substances, stained lightly or strongly with periodic acid Schiff (PAS) was most conspicuous in this case. The first type of them, lightly stained with PAS at room temperature, was widely distributed in the central nervous system (CNS): the white matter of cerebrum and brainstem, subpial and subependymal glial layers, subpial space, perivascular space of small blood vessels, and their adjacent nervous tissue. The second type, strongly stained with PAS, small round or ellipsoid bodies, was found in the subpial, subependymal and perivascular glial layers. The first type of PAS-positive substances might be fatty alcohols or their metabolites, and the second type, some degraded products of lipids in astrocytic processes. Lipofuscin-like substances were accumulated in perivascular macrophages located around small blood vessels. Spheroid bodies (axonal swellings) were frequently observed in relay nuclei: lateral geniculate body (LGB), pontine nuclei, inferior olivary nuclei, posterior funicular nuclei, or cerebellar dentate nuclei. A lot of PAS-positive fine granules were contained in a spheroid body of LGB. Scarcity of myelinated nerve fibers was recognized in the cerebral and cerebellar white matter and the corticospinal tracts of spinal cord. Focal cortical dysgenesis, resembling that of unlayered polymicrogyria, was observed in bilateral insular cortices. Further histochemical studies are needed to explore the exact pathogenesis, but widespread deposition of PAS-positive substances in CNS may support the supposition that SLS is one of congenital errors of lipid metabolism.  相似文献   
84.
伦潭水利枢纽工程项目建议书阶段采用了按效益比例和按替代工程投资比例两种分摊方法进行投资分摊 经分析比较 ,选择按效益比例分摊得到的各部门投资作为经济评价的依据  相似文献   
85.
An intermittent and cyclic regimen with All-Trans Retinoic Acid (ATRA) and intensive chemotherapy was conducted due to pharmacokinetic studies on ATRA for acute promyelocytic leukemia (APL) in children. We have treated 17 children with APL using ATRA for remission induction followed by an intermittent schedule of ATRA plus intensive chemotherapy (APL-ATRA protocol). There were 10 males and 7 females. The median age was 9.0 years old. The median baseline white blood cell count was 12.1 x 10(3)/microliter, hemoglobin 7.8 g/dl, platelet 4.5 x 10(4) microliters at diagnosis. Sixteen patients showed t(15; 17) translocation. RT-PCR analysis was available in 15 patients and showed PML/RAR alpha rearrangement in all patients. Overall, 13 or 17 newly diagnosed patients (88%) achieved complete remission and EFS was 67%. Compared to the control (same chemotherapy without ATRA regimen), remission induction and EFS were significantly increased. The toxicity of ATRA consisted of retinoic acid syndrome in 1 and pseudotumor cerebli in another. Other toxicities included headache, chelitis, gastrointestinal trouble and bone pain. These results suggest that intermittent and cyclic regimen with ATRA and intensive chemotherapy (APL-ATRA protocol) is highly effective for APL patients.  相似文献   
86.
The GT1-1 GnRH neuronal cell lines exhibit highly differentiated properties of GnRH neurons. We have used GT1-1 cells to study the roles of norepinephrine (NE), membrane depolarization, calcium influx, and phorbol esters in the regulation of mitogen-activated protein (MAP) kinase. NE, which is known to stimulate the release of GnRH, induced MAP kinase activity, the tyrosine phosphorylation of MAP kinase, and MAP kinase kinase activity. Forskolin led to activation of MAP kinase comparable with that induced by NE, and a selective inhibitor of cAMP-dependent protein kinase, H8, attenuated the NE-induced activation of MAP kinase. On the other hand, elimination of extracellular calcium by EGTA completely blocked NE-induced tyrosine phosphorylation of MAP kinase, and a selective inhibitor of calcium/calmodulin-dependent protein kinase, KN-62, attenuated the NE-induced activation of MAP kinase. Furthermore, depolarization of GT1-1 cells with 75 mM KCl, 10 microM BayK 8644, or 1 microM calcium ionophore (A23187) induced rapid tyrosine phosphorylation of MAP kinase. The omission of calcium from the extracellular medium completely abolished these effects of tyrosine phosphorylation of MAP kinase. Phorbol 12-myristate 13-acetate (PMA) also induced MAP kinase activity, but pretreatment of the cultured cells with PMA to down-regulate protein kinase C did not abolish the activation of MAP kinase by NE. In addition, although phosphorylation of Raf-1 kinase was stimulated by PMA, this phosphorylation was not induced by either NE or A23187. These results demonstrate that NE activates MAP kinase directly in GT1-1 cells, and that the effect of NE is mediated by increase in the cAMP level and by calcium influx, but not by PMA-sensitive protein kinase C or Raf-1 kinase.  相似文献   
87.
STUDY OBJECTIVE: To determine the effect of adding the nebulized anticholinergic drug ipratropium bromide to standard therapy compared with standard therapy alone for acute severe asthma (peak expiratory flow rate [PEFR] < 50% of predicted) in children presenting to the emergency department. METHODS: Ninety children aged 6 to 18 years were randomly assigned to two groups in a prospective, double-blind, placebo-controlled study performed in the ED of an urban children's hospital. All children received nebulized albuterol solution (.15 mg/kg) every 30 minutes, and all received oral steroids with the second dose of albuterol. Children in group 1 received ipratropium bromide (500 micrograms/dose) with the first and third dose of albuterol those in group 2 received saline placebo instead of ipratropium. Pulmonary functions (PEFR and 1-second forced expiratory volume [FEV1]) and physiologic measurements were assessed every 30 minutes up to 120 minutes. By chance, the baseline values for percent of predicted PEFR and FEV1 differed between the two groups. Therefore a multivariate model accounting for both time and baseline effects was used to compare the response between groups. RESULTS: On average, and adjusting for baseline measures, children in the ipratropium group had a significantly greater improvement in percent of predicted PEFR than did children in the placebo group at 60 minutes (P = .02), 90 minutes (P = .002), and 120 minutes (P < .0001). The improvement in percent predicted FEV1 was significantly greater for children in the ipratropium group only at 120 minutes (P = .013). Nine children (20%) from the ipratropium group and 14 (31.1%) from the control group were admitted (P = .33, chi 2). There were no significant adverse effects attributable to the ipratropium, and there was no relation between ipratropium use and changes in pulse, respiratory rate, blood pressure, or oxygen saturation. CONCLUSION: We detected significant improvement in pulmonary function studies over 120 minutes in children with severe asthma who were given nebulized ipratropium combined with albuterol and oral steroids, compared with children who received the standard therapy. Further study is needed to determine whether early use of ipratropium decreases the need for hospitalization.  相似文献   
88.
89.
The aim of this study was to compare hemodynamic responses to intubation and pin head-holder application in two groups of neurosurgical patients given oral clonidine (3 microg/kg) or oral temazepam (10-20 mg) 90 min before the induction of anesthesia. Fifty patients undergoing elective craniotomy were randomized to either group. Anesthesia was induced with i.v. propofol 1500 mg/h, fentanyl 4 microg/kg, vecuronium 0.15 mg/kg, and lidocaine 1.5 mg/kg and was maintained with propofol 6 mg x kg(-1) x h(-1). Mean arterial blood pressure (MAP) and heart rate were recorded before the induction of anesthesia and before and after intubation and application of the pin head holder. Interventions required to maintain hemodynamic stability were compared between groups. Preinduction sedation scores and MAP values were similar between groups. MAP was significantly lower (P = 0.031) in the clonidine group after pin head-holder application. Interventions to stabilize MAP were not significantly different between groups (P = 0.11). We conclude that clonidine is effective in reducing the MAP increase with pin head-holder application in patients undergoing craniotomy. Implications: In this study, we investigated an approach to the prevention of increased blood pressure often seen during the early part of anesthesia for brain surgery. Oral clonidine was effective in reducing the mean arterial blood pressure increase resulting from pin head-holder application. Clonidine, a blood pressure-reducing drug, was given to 25 patients before anesthesia. Their blood pressure measurements were then compared with those of 25 patients not given clonidine.  相似文献   
90.
Acetaldehyde present in the blood of bull, chicken, hamster, horse, human, monkey, pig, rabbit, rat and sheep, was quantitatively analyzed by a newly developed gas chromatographic method. Acetaldehyde in a blood sample was reacted with cysteamine to give 2-methylthiazolidine, which was extracted with dichloromethane and subsequently analyzed by gas chromatography with a fused-silica capillary column and a nitrogen-phosphorus detector. The quantities of acetaldehyde found in blood ranged from 2.04 micromol/ml (hamster) to 14.8 micromol/ml (pig). The quantity of acetaldehyde recovered from human blood was 6.17 micromol/ml.  相似文献   
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