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81.
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83.
Six patients with immature teratoma of the ovary were treated with surgery and chemotherapy. Surgical management consisted of unilateral salpingo-oophorectomy, biopsy and conservation of the contralateral ovary, and biopsy of peritoneal implants. Triple-agent chemotherapy with vincristine, actinomycin D, and cyclophosphamide was given to four patients and appeared to be beneficial. Radiation therapy was not employed. Local resection of teratomatous recurrences was frequently necessary. Thorough sampling of this tumor is mandatory for establishment of an exact pathologic diagnosis. All six patients are surviving in good health at 1-8-yr follow-up. The prognosis of immature teratoma in the child or adolescent appears more favorable than previously appreciated.  相似文献   
84.
By exploiting the relatively high volatility of In etch products in CH4/H2 discharges, we were able to obtain a maximum selectivity for InGaP over GaAs of ∼20 at low ion energies and fluxes. Three different inert gas additives to CH4/H2 were examined, with Ar producing higher selectivities than He or Xe. This process is attractive for selective removal of the InGaP emitter in the fabrication of heterojunction bipolar transistors.  相似文献   
85.
Optical coatings of the high band gap oxides ZrO2, Y4Al2O9, Al2O3, MgAl2O4 and SiO2 were prepared by reactive sputtering to evaluate their potential for use in fusion lasers operating at wavelengths ranging from the UV to the near IR. The optical properties (refractive index, band gap, absorption and scattering) and materials properties (crystalline structure, grain size, stoichiometry and surface topography) of these oxides are reported and their suitability for use at 0.25 and 1.06 μm is discussed. The deposition rates and the influences of deposition conditions on the optical and materials properties are also reported.  相似文献   
86.
This paper addresses the need for detailed chemical information on the fine particulate matter (PM) generated by commercial aviation engines. The exhaust plumes of seven turbofan engine models were sampled as part of the three test campaigns of the Aircraft Particle Emissions eXperiment (APEX). In these experiments, continuous measurements of black carbon (BC) and particle surface-bound polycyclic aromatic compounds (PAHs) were conducted. In addition, time-integrated sampling was performed for bulk elemental composition, water-soluble ions, organic and elemental carbon (OC and EC), and trace semivolatile organic compounds (SVOCs). The continuous BC and PAH monitoring showed a characteristic U-shaped curve of the emission index (EI or mass of pollutant/mass of fuel burned) vs fuel flow for the turbofan engines tested. The time-integrated EIs for both elemental composition and water-soluble ions were heavily dominated by sulfur and SO(4)(2-), respectively, with a ~2.4% median conversion of fuel S(IV) to particle S(VI). The corrected OC and EC emission indices obtained in this study ranged from 37 to 83 mg/kg and 21 to 275 mg/kg, respectively, with the EC/OC ratio ranging from ~0.3 to 7 depending on engine type and test conditions. Finally, the particle SVOC EIs varied by as much as 2 orders of magnitude with distinct variations in chemical composition observed for different engine types and operating conditions.  相似文献   
87.
On the cover.     
Presents a biographical article about the artist, Mary Jane Q. Cross, whose work Morning on the Sugar River, graces the cover of this issue of American Psychologist. Portions of the article are based on an interview with the artist on April 9, 2007. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
88.
The regulatory mechanism of Bcl-2 protein expression was investigated in SH-SY5Y cells, the human neuroblastoma cell line that expresses natively Bcl-2 proteins. WHen the cells were treated with 12-O-tetradecanoylphorbol 13-acetate (TPA) or retinoic acid, the level of Bcl-2 protein was increased compared with the control. These effects were inhibited by pretreatment with a protein kinase C (PKC) inhibitor, staurosporine or calphostin C. The level of Bcl-2 protein was also increased by treatment with carbachol, a muscarinic acetylcholine receptor (mAChR) agonist, and the effect were also inhibited by pretreatment with staurosporine or calphostin C. An addition, a carbachol-induced increase in Bcl-2 protein levels and a transient elevation of [Ca2+]i were inhibited by pretreatment with 4-DAMP (4-diphenylacetoxy-N-methylpiperidine), an m3 mAChR antagonist. In contrast, the level of Bcl-2 protein was decreased by treatment with dibutyryl cAMP (diBu-cAMP), forskolin, or cholera toxin, and the effects of diBu-cAMP were inhibited by pretreatment with a protein kinase A (PKA) inhibitor, H-89. From these results, we suggest that the expression of Bcl-2 proteins is regulated by PKC and PKA in positive and negative manners, respectively, in SH-SY5Y cells. Furthermore, the nucleosomal DNA fragmentation induced by serum depletion for 4 h was observed in SH-SY5Y cells when the level of Bcl-2 protein was down-regulated by treatment with 1 mM diBu-cAMP for 3 days, although the DNA fragmentation by serum depletion for 4 h was not observed in nontreatment cells, indicating that Bcl-2 proteins whose expression is regulated by PKC and PKA play important roles in serum depletion-induced apoptosis.  相似文献   
89.
The uptake and elimination of Cr(VI) in a male volunteer who ingested 2 L/d of water containing 2 mg/L for 17 consecutive days was measured. Total chromium was measured in urine, plasma, and red blood cells (RBCs) for 4 d prior to and 2 wk after dosing (34 d total). The estimated bioavailability (2%) and the plasma elimination half-life (36 h) were consistent with our previous studies of Cr(VI) ingestion in humans. Steady-state chromium concentrations in urine and blood were achieved after 7 d of Cr(VI) ingestion. Both plasma and red blood cell (RBC) chromium concentrations returned rapidly to background levels within a few days after cessation of dosing. Since the concentration of chromium in the RBC should not decrease quickly if the chromium had entered the RBC as Cr(VI), these data support our prior work suggesting that concentrations of 10 mg Cr(VI)/L or less in drinking water of exposed humans appears to be completely reduced to Cr(III) prior to systemic distribution. Clinical chemistry data indicate that no toxicity occurred.  相似文献   
90.
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