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991.
Weight gain by adult cat fleas, Ctenocephalidesfelis (Bouché), was influenced primarily by the concentrations of protein and sodium chloride in the feeding solution. After 48 h of feeding, fleas fed whole blood weighed almost twice as much as fleas fed plasma or hemolyzed blood and 1.25 times as much as fleas fed 0.15 M sodium chloride. When fleas were fed sodium chloride solutions ranging from 0 to 0.5 M, weight gain was greatest on the 0.15- or 0.2-M solutions. Weight gain decreased significantly when fleas were fed plasma, hemolyzed blood or 0.3 or 0.5 M sodium chloride in place of whole blood, but improved when plasma was diluted 100% and when hemolyzed blood was diluted 10% with distilled water. Adenosine-5'-triphosphate did not appear to stimulate weight gain in cat fleas; weight gain was unchanged in fleas fed hemolyzed blood or 0.15 M sodium chloride to which 0.005 M ATP was added. Insemination did not occur in starved fleas or those fed protein-free diets. When fleas were starved or fed distilled water, sodium chloride, or other salt solutions, sperm was transferred from the testes to the vas deferens in 91-94% of males, but no females were inseminated. In contrast, when fleas were fed whole blood, hemolyzed blood, plasma, or bovine serum albumin (3.5 or 7.0 g/deciliter) dissolved in 0.15 M saline, 80, 80, 10, and 10% of the females were inseminated, respectively.  相似文献   
992.
993.
Various diluents, stabilizers, buffers, and storage conditions were assessed for their efficacy in stabilizing cold-adapted influenza virus vaccine. Frozen liquid vaccine formulations, comprised of a normal uninfected allantoic fluid diluent and an SPG (sucrose-phosphate-glutamate) stabilizer, generated complete stability of H1N1, H3N2, and Type B strains for at least 1 year of storage at -20 degrees C. The ability to store live influenza virus frozen liquid vaccines, at the moderate temperature of -20 degrees C, has not been demonstrated previously. This significant advance could facilitate influenza vaccine storage and administration in the clinic, and subsequently increase marketability. The stability of lyophilized formulations was also augmented by the addition of 2% Casitone and the control of pH with 0.066 M phosphate in the SPG stabilizer. This alternative formulation may be useful in markets where freezing is not feasible or short-term room temperature storage is necessary.  相似文献   
994.
The Continence Product Evaluation Network (CPE network) is funded by the Medical Devices Agency (MDA) of the Department of Health, to undertake comparative evaluations of continence products. There are a wide variety of continence products on the UK market and very little information is available to aid product selection. The aim of this study was to evaluate washable pants with integral pads for women with light incontinence. A randomized multiple cross-over design was used. Seventy-two women tested each of the 10 products that were available on the UK market at the time of the evaluation. Both subjective and objective outcome measures were used to evaluate the products. Products performed similarly in terms of leakage but there were statistically significant differences in other performance aspects, e.g. fit and discreteness. This study should be valuable in enabling purchasers, carers and users to make informed decisions when purchasing products.  相似文献   
995.
Dean A 《Nursing times》2002,98(43):34-35
Patients use many different coping mechanisms when they are facing a terminal diagnosis, but it should not be assumed that they want to talk to nurses about the terminal nature of their illness. Research shows that a proportion of patients may want to, so this article suggests that best practice with regard to communication in palliative care could be achieved by using a sensitive assessment of how each patient chooses to cope with his or her situation rather than a uniform approach to care.  相似文献   
996.
Background The purpose of this study was to assess frequency, risk factors, treatment, and complications of very young patients with acute myocardial infarction (MI) at the University of Michigan Medical Center (UMMC). Methods From a database of 976 consecutive patients admitted to the UMMC with acute MI between 1995 and 1998, we compared care and outcomes of patients divided into 3 age categories: <46 years, 46-54 years, and >54 years. Risk factors, presenting symptoms, type of MI, management, complications, and hospital outcomes of the 3 groups were evaluated. Results Young patients represented >10% of all patients with acute MI, and >25% of these individuals were women, a number considerably higher than seen in previous studies. This group of young patients was more likely to have Q-wave MI and risk factors such as family history and tobacco use and less likely to have a history of angina. Although all 3 groups received similar inpatient treatment, there was more attention paid to risk factor modification such as smoking cessation and referral to cardiac rehabilitation in younger individuals. Young patients had fewer in-hospital complications and a lower mortality rate. Conclusions At the University of Michigan, >1 in 10 with acute MI is <46 years old. Data suggest that current management and aggressive risk factor modification are quite good in this particular group, and overall the mortality rate is very low. (Am Heart J 2002;143:56-62.)  相似文献   
997.
We studied 18 patients with myelodysplastic syndrome (MDS), measuring clonality and T-cell receptor Vbeta (TCRBV) expression of CD4 and CD8 T cells by polymerase chain reaction and by flow cytometric analysis of TCRBV families. The CD4 and CD8 T-cell repertoire in most MDS patients is characterized by an abnormal TCRBV-restricted expansion of T cells in CD4 and CD8 cells, and increased expression of the CD8 effector marker CD57 of multiple TCRBV in CD8 cells. Clonality analysis of CD4 and CD8 cells showed that seven of 10 patients analysed had a major clone in the CD8 cells but not in CD4 cells. Furthermore, in one patient we found that both the CD57- and CD57+ fraction contained the clone (which was absent from the TCRBV-negative fraction). These data suggest that, in MDS, multiple T-cell expansions can be found in both helper and cytotoxic T cells, and that, in the CD8 cells, T cells functionally differentiate in vivo from memory to effector T cells. Together, these data support the hypothesis of the involvement of T cells in the pathogenesis of MDS.  相似文献   
998.
999.
This study investigates a complex task in which rhythmic and discrete components have to be combined in single-joint elbow rotations. While previous studies of similar tasks already reported that the initiation of the discrete movement is constrained to a particular phase window of the ongoing rhythmic movement, interpretations have remained contradictory due to differences in paradigms, oscillation frequencies, and data analysis techniques. The present study aims to clarify these findings and further elucidate the bidirectional nature of the interaction between discrete and rhythmic components. Participants performed single-degree-of-freedom elbow oscillatory movements at five prescribed periods (400, 500, 600, 800, 1000 ms). They rapidly switched the midpoint of oscillation to a second target after an auditory signal that occurred at a random phase of the oscillation, without stopping the oscillation. Results confirmed that the phase of the discrete movement initiation is highly constrained with respect to the oscillation period. Further, the duration, peak velocity, and the overshoot of the discrete movement varied systematically with the period of the rhythmic movement. Effects of the discrete-onto-rhythmic component were seen in a phase resetting of the oscillation and a systematic acceleration after the discrete movement, which also varied as a function of the oscillation period. These results are interpreted in terms of an inhibitory bidirectional coupling between discrete and rhythmic movement. The interaction between discrete and rhythmic movement elements is discussed in comparison to sequential and gating processes suggested previously. Electronic Publication  相似文献   
1000.
This paper describes the history, current status, and objectives and potential impact of the new National Institute of Biomedical Imaging and Bioengineering (NIBIB). Three of the authors (Hendee, Chien, and Maynard) have been involved over several years in the effort to raise the identity of biomedical imaging and bioengineering at the National Institutes of Health. The fourth author (Dean) is the Acting Director of the newly formed NIBIB. These individuals have an extensive collective knowledge of the events that led to formation of the NIBIB, and are intimately involved in shaping its objectives and implementation strategy. This special report provides a historical record of activities leading to establishment of the NIBIB, and an accounting of present and potential advances in biomedical engineering and imaging that will be facilitated and enhanced by NIBIB. The National Institute of Biomedical Imaging and Bioengineering represents a coming of age of biomedical engineering and imaging, and offers great potential to expand the research frontiers of these disciplines to unparalleled heights. © 2002 Biomedical Engineering Society. PAC2002: 8762+n, 8759-e, 0178+p, 0165+g, 8761-c  相似文献   
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