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排序方式: 共有572条查询结果,搜索用时 15 毫秒
21.
Alcohol problems in acute male medical admissions 总被引:2,自引:0,他引:2
22.
A method for the isolation of polytene nuclei from salivary glands cells of the Diptera Rhynchosciara americana is described. The stage-specific morphological pattern of the chromosome is maintained during the isolation. The isolated nuclei show two distinct RNA polymerase activities, namely I and II, characterized on the basis of ionic requirements and alpha-amanitin sensitivity. Studies of the product under the incubation conditions show that the system allows the synthesis of high-molecular weight RNA, beside a low molecular weight peak which may comprise pre-4S and 5S RNAs. Autoradiographic studies carried out in the presence or absence of the toxin alpha-amanitin showed that micronucleoli contain products of RNA polymerase type I activity (ribosomal RNA) and that the DNA puffs are engaged in alpha-amanitin sensitive RNA synthesis and thus are sites of polymerase type II activity. 相似文献
23.
A novel front-face flash-monitoring algorithm for remote sensing of the thermal diffusivity and the absorption coefficient
at the excitation wavelength of thin film materials is presented. The method relies on the surface transient temperature vs.
time curve initiated by a short-duration heating pulse that is followed by time intervals during which the temperature response
depends sensitively on the absorption coefficient and thermal diffusivity. An analytical solution of the problem has been
derived to solve the inverse heat-transfer problem and, by comparison with a numerical experiment, to check the accuracy of
the proposed algorithm for obtaining the absorption coefficient at the excitation wavelength and thermal diffusivity. The
uncertainty of the proposed method is better than 0.1%.
Paper presented at the 17th European Conference on Thermophysical Properties, September 5–8, 2005, Bratislava, Slovak Republic. 相似文献
24.
25.
GE O'Keefe RV Maier P Diehr D Grossman GJ Jurkovich D Conrad 《Canadian Metallurgical Quarterly》1997,132(8):920-4; discussion 925
OBJECTIVES: To estimate the expected costs for acute trauma care, to quantify the costs associated with the development of complications in injury victims, and to determine the deficit incurred by patients in whom complications develop. DESIGN: A retrospective, cohort design. SETTING: A referral trauma center. PATIENTS: A total of 12,088 patients admitted to a single regional trauma center during a period of 5 years. INTERVENTIONS: This is an observational study, and no interventions specific to this study are included in the design. MAIN OUTCOME MEASURES: (1) The expected costs for injury victims based on readily available clinical data. (2) The costs associated with the most important complications of trauma. (3) The effect of complications on inadequate reimbursement for trauma care. RESULTS: The expected costs were estimated using a linear model incorporating demographic variables and measures of injury severity. The expected costs averaged $14,567, and the observed costs averaged $15,032. Six complications were important predictors of cost. These included adult respiratory distress syndrome, acute kidney failure, sepsis, pneumonia, decubitus ulceration, and wound infections. For 1201 individuals with these complications, the predicted costs averaged $23,266 and the observed costs averaged $47,457. The mean excess costs for a single complication ranged from $6669 to $18,052. Multiple complications led to greater increases in excess cost, averaging $110,007 for the 62 patients with 3 or more complications. Costs exceeded reimbursement to a much greater degree in those in whom any of the 6 complications developed. CONCLUSION: Expected hospital costs can be estimated using admission clinical data. Each of 6 complications was associated with enormous increases in costs, indicating their importance as a cause of avoidable expenditures in injury victims and identifying situations in which reimbursement may not be adequate. 相似文献
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27.
Respiratory obstruction caused by a round worm is rate. A fatal case of the complication in a three-year-old child was encountered at the Nehru Hospital attached to the Postgraduate Institute of Medical Education and Research, Chandigarh, India. 相似文献
28.
RV Farese M Standaert B Yu H Hernandez DR Cooper 《Canadian Metallurgical Quarterly》1993,268(27):19949-19955
In rat adipocytes and soleus muscles, 2-hydroxypropyl-beta-cyclodextrin (CD) was found to have a relatively small or no effect on basal or insulin-stimulated hexose uptake, but markedly enhanced hexose uptake effects of phorbol esters and/or diacylglycerol. In rat adipocytes, the CD-induced enhancement of hexose uptake during concurrent phorbol ester treatment was not associated with an increase in GLUT4 glucose transporter translocation to the plasma membrane, which was stimulated comparably by insulin and phorbol esters. Moreover, CD appeared to activate or facilitate the activation of glucose transporters subsequent to their translocation to the plasma membrane during ongoing phorbol ester treatment. In rat adipocytes, CD also enhanced the translocation of protein kinase C (PKC)-beta to the plasma membrane during the action of phorbol esters, which alone had little or no effect on this specific PKC translocation. Although it is uncertain how CD alters the function of plasma membranes to enhance the translocation of PKC-beta to, and the activation of glucose transporters within, this subcellular fraction during phorbol ester treatment, our findings provide direct support for a two-step model in the activation of glucose transport. In addition, it seems clear that, at least in some cell types, simple phorbol ester treatment does not necessarily serve as a ubiquitous activator of all activable PKC pools and all potential PKC-mediated responses. 相似文献
29.
The control of hemorrhage in hypothermic patients with platelet and clotting factor depletion is often impossible. Determining the cause of coagulopathic bleeding (CB) will enable physicians to appropriately focus on rewarming, clotting factor repletion, or both. Objective: To determine the contribution of hypothermia in producing CB and ascertain if simultaneous hypothermia and dilutional coagulopathy (DC) interact synergistically. Method: Prothrombin time, partial thromboplastin time, and platelet function were determined at assay temperatures of 29 degrees to 37 degrees C on normal and critically ill, noncoagulopathic (NC) individuals. Dilutional coagulopathy was created using buffered saline and the assays repeated. Results: Hypothermic assay at < or = 35 degrees C significantly prolonged coagulation times. The effect of hypothermia on NC and DC samples was not different. Conclusion: Assays performed at 37 degrees C underestimate coagulopathy in hypothermic patients. The effect of hypothermia on NC and DC is not different, indicating the lack of a synergistic effect. Normalization of clotting requires both rewarming and clotting factor repletion. 相似文献
30.
D Perrotti S Bonatti R Trotta R Martinez T Skorski P Salomoni E Grassilli RV Lozzo DR Cooper B Calabretta 《Canadian Metallurgical Quarterly》1998,17(15):4442-4455
The leukemogenic potential of BCR/ABL oncoproteins depends on their tyrosine kinase activity and involves the activation of several downstream effectors, some of which are essential for cell transformation. Using electrophoretic mobility shift assays and Southwestern blot analyses with a double-stranded oligonucleotide containing a zinc finger consensus sequence, we identified a 68 kDa DNA-binding protein specifically induced by BCR/ABL. The peptide sequence of the affinity-purified protein was identical to that of the RNA-binding protein FUS (also called TLS). Binding activity of FUS required a functional BCR/ABL tyrosine kinase necessary to induce PKCbetaII-dependent FUS phosphorylation. Moreover, suppression of PKCbetaII activity in BCR/ABL-expressing cells by treatment with the PKCbetaII inhibitor CGP53353, or by expression of a dominant-negative PKCbetaII, markedly impaired the ability of FUS to bind DNA. Suppression of FUS expression in myeloid precursor 32Dcl3 cells transfected with a FUS antisense construct was associated with upregulation of the granulocyte-colony stimulating factor receptor (G-CSFR) and downregulation of interleukin-3 receptor (IL-3R) beta-chain expression, and accelerated G-CSF-stimulated differentiation. Downregulation of FUS expression in BCR/ABL-expressing 32Dcl3 cells was associated with suppression of growth factor-independent colony formation, restoration of G-CSF-induced granulocytic differentiation and reduced tumorigenic potential in vivo. Together, these results suggest that FUS might function as a regulator of BCR/ABL leukemogenesis, promoting growth factor independence and preventing differentiation via modulation of cytokine receptor expression. 相似文献