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121.
John-Paul Jones G. K. Surya Prakash George A. Olah 《Israel journal of chemistry》2014,54(10):1451-1466
With rising levels of CO2 in our atmosphere, technologies capable of converting CO2 into useful products have become more valuable. The field of electrochemical CO2 reduction is reviewed here, with sections on mechanism, formate (formic acid) production, carbon monoxide production, reduction to higher products (methanol, methane, etc.), use of flow cells, high pressure approaches, molecular catalysts, non-aqueous electrolytes, and solid oxide electrolysis cells. These diverse approaches to electrochemical CO2 reduction are compared and contrasted, emphasizing potential processes that would be feasible for large-scale use. Although the focus is on recent reports, highlights of older reports are also included due to their important contributions to the field, particularly for high-rate electrolysis. 相似文献
122.
Conformational properties of the molecules of angiotensin II and some of its analogs are analysed with regard to the quantitative characteristics of their biological activities. Connections between low-energy conformations of angiotensin II and its biological functions are established. The hormone's spatial structures plausible in terms of interactions with the specific receptors located in smooth muscles and adrenal cortex tissues have been identified. 相似文献
123.
OBJECTIVE: This paper identifies specific data items for use by state and local agencies in a maternal and child oral health needs assessment model. METHODS: A modified Delphi approach was used to develop consensus on items for inclusion in the data set and their relative importance. Initially, 31 data items were chosen from several national sources. All state dental directors, along with other selected administrators and advisory committee members for this process, were asked to categorize each of the data items as core (essential), important but optional, or of lesser importance. Short comments about each data item were accepted, as were additions to the list of data items. Two rounds of comments were held. RESULTS: Eleven data items/types of information were selected as core items to be included in all needs assessments. All but one of these items were determined by the scores of the respondents. The advisory committee strongly recommended that at least one core item relate to the public's perception of oral health. Some differences in perceived importance of several items existed among the state dental directors, local dental directors, and the advisory committee. Twenty-one items were identified as being important, but optional, and seven were considered less than important and not included in the model data set. CONCLUSIONS: A modified Delphi approach facilitated the development of core and optional data items for a model oral health needs assessment. This model has potential for a common reporting mechanism so that states and local dental programs can share data. 相似文献
124.
OA Stafejeva LS Khailova AG Katrukha TV Bulargina 《Canadian Metallurgical Quarterly》1995,37(1):167-173
It has been shown that monoclonal antibody (mAb) F7F10 raised against pyruvate dehydrogenase component (E1) of pigeon breast muscle pyruvate dehydrogenase complex (PDC) has no influence on the E1 activity, measured in the system with artificial oxidants. However it inhibited the full NAD+ and coenzyme A dependent activity of PDC. The competition of the F7F10 antibody with the E2 component of PDC for the binding with E1 was revealed by immunoenzymatic and kinetic analysis. It is suggested that F7F10 mAb interacts with an antigenic determinant, located in the immediate vicinity of or overlapping with the E1 region, responsible for the interaction with the E2 component of PDC. 相似文献
125.
GJ Crawford TV Chirila S Vijayasekaran PD Dalton IJ Constable 《Canadian Metallurgical Quarterly》1996,12(4):525-529
BACKGROUND: We developed a core-and-skirt keratoprosthesis, with both components made from poly(2-hydroxyethyl methacrylate) (PHEMA) hydrogels. The identical chemical nature of both spongy skirt and transparent core assures a permanent union between them. We have previously shown that PHEMA sponges, within a certain range of pore size, can support cellular invasion and neovascularization when implanted into the rabbit cornea. The present study is the first to evaluate the behavior of the whole prosthesis after implantation into the rabbit cornea. METHODS: Hydrogel keratoprostheses were inserted intrastromally into the corneas of seven rabbits and histologically examined by light microscopy in five eyes enucleated at 8, 12, and 14 weeks. RESULTS: None of the implants extruded over this period. Both clinical and histopathologic examination showed that the keratoprostheses were well tolerated by the host tissue. The porous skirt was fully integrated into the stroma by fibrovascular invasion, and no capsule formed around the implants. Stromal melting anterior to the implant occurred in two cases, but this did not affect the fixation of the keratoprostheses. CONCLUSIONS: This study indicates that our keratoprosthesis can prevent extrusion in the short term when inserted into an intrastromal pocket of the rabbit eye. 相似文献
126.
127.
本文主要阐述了微处理机磁通测量数据处理装置的原理以及硬件电路设计。文中对测量电路进行了详细分析,给出了软件程序设计框图。 相似文献
128.
129.
TM Archakova IR Baryliak TV Nikitchyna TD Zadorozhna 《Canadian Metallurgical Quarterly》1998,32(1):96-107
Perinatal pathology and morbidity takes the leading role in children pathology and morbidity today. These indices are of significance for the pregnant women of high risk group pregnant women in the age of 35 and above occupying peculiar place in this group. In this connection the morphological studies of chorion and placenta biopsies in this group of patients are important and urgent. The cytogenetical analysis of these tissues allows one to solve completely the problems of the presence or absence of chromosome fetal malformations in terms of 8-24 weeks, when the elimination of fetus is still possible. 相似文献
130.
TV Cacciarelli M Green R Jaffe GV Mazariegos A Jain JJ Fung J Reyes 《Canadian Metallurgical Quarterly》1998,66(8):1047-1052
BACKGROUND: Posttransplant lymphoproliferative disease (PTLD) after pediatric liver transplantation has been associated with high mortality rates. METHODS: The present study examined 282 consecutive pediatric liver transplant recipients from October 1989 to June 1996 who received primary tacrolimus immunosuppression. The aim was to determine the incidence of PTLD, management strategies, and patient outcome. RESULTS: The incidence of PTLD was 13% (361282) with a mean age of 5.5+/-0.7 years (range 0.6 to 15) at diagnosis. The average time from transplantation to PTLD was 10.1+/-2.1 months. Initial treatment of PTLD consisted of reduction (3 patients) or discontinuation (33 patients) of tacrolimus and initiation of antiviral therapy (intravenous ganciclovir, 14 patients; intravenous acyclovir, 22 patients; or both, 5 patients). Alpha-interferon was used in four patients (two successfully). One patient also received gamma-interferon, chemotherapy, and radiation for a central nervous system lesion. Chemotherapy was also used in one patient with Burkitt's, whereas one patient with a pulmonary lesion received additional radiation therapy. Three patients received supportive surgery for gastrointestinal involvement, and one patient had a splenectomy for hemolysis. Overall mortality was 22% (8/36) with 5 (14%) PTLD-related deaths (disseminated disease, 4 patients; bowel perforation, 1 patient). Of 31 survivors, 23 had acute rejection at a median time of 24 days after PTLD, with 2 patients developing chronic rejection. One patient required retransplantation. Present immunosuppression consists of tacrolimus monotherapy in 14 patients, tacrolimus/prednisone in 8 patients, and none in 6 patients. CONCLUSION: In summary, PTLD can be successfully treated with reduction of immunosuppression and administration of antiviral agents in most patients. The management of rejection after PTLD requires reassessment of disease status and judicious reintroduction of immunosuppression therapy. 相似文献