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1.
Papaya proteinase omega (pp omega) has been purified from dried latex both by immunoaffinity and traditional methods. Kinetic analysis revealed that (1), the pp omega-catalysed hydrolysis of N-benzoyl-L-arginine p-nitroanilide (BApNA) has a lower specificity (kcat/Km) than the same reaction catalysed by papain; (2), the pp omega-catalysed hydrolysis of a tripeptide substrate having phenylalanine at the second position (S2-site) showed a more similar specificity to that catalysed by papain; (3), the significant difference between the two enzymes is that steady state kinetics with both L-BApNA and a tripeptide enables the identification in pp omega of other ionizations affecting binding. The active sites of papain and pp omega can therefore be distinguished by pH-dependence of kcat/Km.  相似文献   
2.
We sought to examine the prevalence of self-reported multiple cardiovascular disease (CVD) risk factors (hypertension, high blood cholesterol, diabetes, overweight, and current smoking) among women in 1992 and 1995 in the United States using data from the Behavioral Risk Factor Surveillance System. In 1992, 37.5%, 34.4%, and 28.1% of women had zero, one, and two or more of the five risk factors, respectively. In 1995, the respective estimates were 35.5%, 34.3%, and 30%. In both years, the prevalence of two or more risk factors increased with age, decreased with educational level, was higher among black women (lowest among Hispanic women and women of other ethnic groups), and higher among women reporting cost as a barrier to healthcare. The percentage of women with two or more risk factors was higher in 1995 than in 1992 for 35 of 48 states, being statistically significant for 7 states. The percentage of women with at least two risk factors was not significantly lower in 1995 than in 1992 for any state. A higher percentage of women reported having multiple CVD risk factors in 1995 compared with 1992. A multifactorial approach to primary prevention and risk factor reduction should be encouraged to help reduce the prevalence and burden of CVD among women.  相似文献   
3.
PURPOSE: To examine the feasibility and reliability of ratings completed by hospital-based registered nurses of the humanistic qualities, communication skills, and selected aspects of the clinical skills of practicing internists. METHOD: In 1988-1989, registered nurses who worked in the same 175 hospitals as 232 internists with admitting privileges at these hospitals rated the internists' performances. The nurses were selected from medicine floors, specialty floors, and intensive care units and/or critical care units, using lists provided by head nurses. A total of 1,877 rating questionnaires with 13 performance categories were collected (with a mean of 8.01 nurses per internist). The ratings were analyzed to determine measurement characteristics and the relationships of the nurses' demographic characteristics to the ratings. In addition, for each of ten performance categories for 152 of the internists, the average rating each internist received from nurses was compared with the average rating each internist received from peer physicians. Statistical analysis used Pearson correlations, canonical correlations, factor analyses, Student's t-tests, analysis of variance, and stepwise multiple regression. Finally, the internists themselves, including physicians who were not actually rated by the nurses, were asked to complete a brief questionnaire that included questions about their opinions of the use of nurses' ratings. RESULTS: The nurses' ratings correlated moderately strongly with the peer physicians' ratings and had a common structure. However, the nurses' ratings were lower for several humanistic qualities, including respect, integrity, and responsibility, and their ratings were higher for medical knowledge and verbal communications. Across the 13 performance categories, approximately 10-15 ratings from nurses were needed to obtain a reliable assessment of an internist's humanistic qualities and communication skills. Many internists felt that nurses' ratings should be used equally with, or at least as a lesser contribution to, ratings by peer physicians of humanistic qualities and communication skills. CONCLUSION: Nurses' ratings appear to provide a feasible and reliable method of evaluating the internists' communication skills and humanistic qualities, when used in conjunction with ratings by peer physicians.  相似文献   
4.
5.
Based on generalization and analysis of instructions and guidelines for therapeutical and prophylactic diets of workers, ways of its optimization were proposed, by using bifide-containing acid dairy products as a preventive agent against possible occupational diseases caused by occupational factors.  相似文献   
6.
The paper presents the results of treating patients with chronic nonspecific diseases of the lung by the use of extracorporeal ultraviolet autoblood irradiation (EUVABI). The marked clinical effect recorded after an EUVABI course coincided with the normalization of an erythrocytic membrane morphoform, which suggests that the severity of allergic and inflammatory reactions was liquidated and blood viscosity was improved. EUVABI led to positive changes in the pattern of morphotypes in the crystallogram of plasma, except the patients who showed no clinical effect, which indicates that plasma crystallography can be used as a diagnostic test in predicting the results of EUVABI application.  相似文献   
7.
The development of control strategies for loiasis is of crucial importance in endemic areas and depends heavily on the accurate identification of occult-infected individuals. A polymerase chain reaction (PCR) and nested polymerase chain reaction (nested PCR) were developed and based on sequences of the repeat 3 region (15r3) of the gene encoding a Loa loa 15-kD protein. The assays was performed on 20 blood samples from occult-infected subjects and 30 from field-collected amicrofilaremic individuals. The size of the initial PCR product was 396 basepairs (bp). When this initial amplification using primers 15r3(1) and 15r3(2) was carried out for 30 cycles, the PCR products from three of the 20 occult-infected and five of the 30 amicrofilaremic individuals were visualized after electrophoresis by staining the gel with ethidium bromide. Subsequent Southern blotting and hybridization with the specific probe revealed hybridization in 19 of 20 occult-infected and 23 of 30 amicrofilaremic samples but only after two days of exposure of the blot to the x-ray film. When the nested PCR was carried out (product size = 366 bp, primers 15r3(3) and 15r3(4)), 19 of 20 occult-infected and 23 of 30 amicrofilaremic samples that were positive by Southern hybridization of the initial PCR products were strongly positive by staining with ethidium bromide. Qualitative Southern blotting of the nested PCR products using the same probe previously described confirmed the ethidium bromide staining results after a very short exposure time of 4 hr. These results demonstrate that the nested PCR amplification product is specific and that its sensitivity in detecting occult loiasis is 95%. This approach has significant promise for the screening of large human populations for active loiasis without the requirement for blotting and hybridization of the PCR products.  相似文献   
8.
Isocyanate-based materials have been used for decades as the basis for high performance adhesives, coatings, and primers. The origin of the excellent adhesion of these materials to metals such as steel has been generally assumed to derive from the condensation of isocyanates with metal hydroxyls to form metal oxide-cyanate esters analogous to urethanes. In this work Fourier transform infrared reflection (FTIR) was used to demonstrate that these esters do indeed form, but that the esterification is preceded by the formation of carbamate salts between the isocyanate and the hydrated metal oxide.

Isocyanate pMDI Polyurethane Steel Adhesion Interface  相似文献   
9.
The goal of this investigation was to determine the effects of allelochemicals on plant respiration that thereby may be responsible for their role in growth inhibition. We have tested the effects of juglone, quercetin, cinnamic acid, and-pinene on respiration rates, and electron partitioning through the cytochrome and alternative respiratory pathways, by measuring on-line oxygen consumption and oxygen isotope fractionation in soybean cotyledon tissue. Cinnamic acid and-pinene decreased the oxygen consumption rate and increased the relative partitioning of electron transport to the alternative pathway. Possible biochemical mechanisms of these effects are discussed.  相似文献   
10.
The viscoelasticity of blood is quantified by studying the oscillatory flow of suspensions of RBC in plasma in 218 μm and 400 μm glass capillary tubes. The flow conditions are chosen to reflect normal physiological flow in small arterial vessels. Data are obtained for suspension hematocrits between 35 and 80 percent, and at physiological temperature (37°C) The results indicate that the elastic component of the viscoelasticity of blood is effectively negligible for the conditions of this study; the measured pressure gradient-flowrate relationship is dominated by the viscous component of blood viscoelasticity.  相似文献   
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