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1.
烘烤罗汉果的适宜温度探讨   总被引:2,自引:1,他引:1  
为了保证罗汉果的质量,我们对烘烤罗汉果的适宜温度进行了探讨,实验结果表明,用50—75℃温度进行加工,罗汉果的质量比较好。  相似文献   

2.
I defend a certain claim about rationing in the context of HIV/AIDS, namely, the 'priority thesis' that the state of a developing country with a high rate of HIV should provide highly active anti-retroviral treatment (HAART) to those who would die without it, even if doing so would require not treating most other life-threatening diseases. More specifically, I defend the priority thesis in a negative way, by refuting two influential and important arguments against it inspired by the Kantian principle of respect for persons. The 'equality argument' more or less maintains that prioritizing treatment for HIV/AIDS would objectionably treat those who suffer from it as more important than those who do not. The 'responsibility argument' says, roughly, that to ration life-saving treatment by prioritizing those with HIV would wrongly fail to hold people responsible for their actions, since most people infected with HIV could have avoided the foreseeable harm of infection. While it appears that a Kantian must think that one of these two arguments is sound, I maintain that, in fact, respect for persons grounds neither the equality nor responsibility argument against prioritizing HAART and hence at least permits doing so. If this negative defence of the priority thesis succeeds, then conceptual space is opened up for the possibility that respect for persons requires prioritizing HAART, which argument I sketch in the conclusion as something to articulate and defend in future work.  相似文献   

3.
Nonparametric models for sensory discrimination methods are developed. In these models, the relationship between the probability of a correct response, Pc, and the measures for sensory discriminability or sensory difference, p1 and p2 are given. On the basis of the models, different sensitivities for triadic tests were compared including 3-AFC and triangle methods with the strong stimulus as the odd sample and with the weak stimulus as the odd sample. Predictions were made which can be tested experimentally.  相似文献   

4.
The degree of vasodilatation achieved by various diagnostic methods (arterial occlusion, ganglionic block established by certain agents, lumbar sympathetic block, spinal anesthesia, and indirect heating) was studied by means of the pneumo-plethysmogram as well as through readings of skin temperature and skin resistance. The data obtained were interpreted as to their value in determining the type of patient with vascular disease for whom lumbar sympathectomy would be of noticeable benefit. Arterial occlusion proved itself a rapid and simple method which in most patients produced satisfactory results. As a rule, lumbar sympathectomy was effective in patients who preoperatively had shown a positive response upon release of arterial occlusion. A negative response, that is, absence of significant increase in blood flow, does not necessarily indicate organic disease, and cannot be taken to mean that lumbar sympathectomy would always be ineffective. Ganglionic block, using 2.6 dimethyl piperidinium bromide or tetraethylammonium ion, was generally less reliable in indicating the probable results of sympathectomy than lumbar sympathetic block or indirect heating. Lumbar sympathetic block with procaine was followed by a greater increase in skin temperature and blood flow than spinal anesthesia, and permitted far more accurate conclusions as to the probable outcome of sympathectomy. Subsequent to indirect heating the plethysmogram showed characteristic differences depending on the degree of vascular disease present. From the effect of this simple, safe and painless method upon the relative blood flow to the toe it becomes possible to arrive at a comparatively accurate estimate of the clinical benefit to be expected from lumbar sympathectomy.  相似文献   

5.
Angiocardiography is indicated in selected cases of heart disease in which a definite diagnosis cannot be made by ordinary methods or in which there is reasonable expectation that the information so obtained may influence the treatment of the patient. Whenever possible, angiocardiography should be done in conjunction with cardiac catheterization. The main indication for angiocardiography is cyanotic congenital heart disease; primarily those cases in which there is a right-to-left shunt. Angiocardiography is occasionally of value in diagnosis of other types of congenital heart disease and in acquired heart disease.  相似文献   

6.
7.
《Journal of phycology》2001,37(Z3):52-52
Waaland, J. R.1 & Stiller, J. W.2 1Department of Botany, University of Washington, Seattle, WA 98195 USA; 2Department of Biology, East Carolina University, Greenville, NC 27858 USA Macroalgae are important components of aquatic ecosystems. Some are harvested or cultivated for economic uses while others are of interest for their phylogenetic or systematic positions. Although most genes known from macroalgae have been isolated for comparative evolutionary analysis, some have been the subject of more detailed molecular investigations. We examine the current state of knowledge for several macroalgae as candidates for genomic study. Selection criteria for target taxa include features such as a well known sexual life history, availability of established laboratory cultures, mutant strains, basic genetic studies, fossil records, and ecological and economic importance. Among the algae to be considered are: Porphyra, Gracilaria, Ectocarpus, Macrocystis, Laminaria, Fucus, Ulva, Chara and Nitella. A strong case can be made for each of these taxa; however, we will emphasize Porphyra yezoensis because of its importance as a food source, its well-characterized and easily manipulated reproductive biology, its relatively small genome size, and recent technical advances in genetic manipulation that should lead to fruitful exploitation of genomic information as it becomes available. Further, the genome of a red alga is an attractive target for comparison with those of other multicellular eukaryotes that have been the object of sequencing projects thus far.  相似文献   

8.
An apparatus for determining the repellency of a chemical compound is described. Its action depends upon the insects' coming into contact with the compound deposited on a glass surface. The numbers of insects settling on treated and untreated glass plates at intervals over a period of 40 min. and under conditions that minimize varying disturbing factors are counted. The quotient obtained by dividing the total numbers on the untreated plates by the total numbers on the treated plates is called the 'repellence quotient', and must reach certain given values before significance is assumed and a compound is regarded as repellent.
Typical results obtained with the apparatus are given and include the detailed determination of the repellency of butoxypolypropylene glycol (MW 800).  相似文献   

9.
害虫防治用玫烟色拟青霉分生孢子粉的干燥工艺优化*   总被引:1,自引:0,他引:1  
陈宜涛  冯明光 《菌物学报》2002,21(4):565-572
用液—固两相法生产的玫烟色拟青霉Paecilomyces fumosoroseus Pfr116菌株的分生孢子粉,在高真空冷冻干燥、高真空室温抽干、35℃下烘干和低真空低热干燥条件下进行不同程序的干燥处理,以筛选适合该菌孢子粉生产的干燥工艺条件。结果表明,低真空(0.1 MPa)低热(30℃)抽干20~24 h的干燥方法最适合用于该菌孢子粉的干燥,既能保证含水量在9.0%以下,又能保证87%以上的活孢率和1130亿~1310亿/g的含孢量,而且操作简便,成本较低,可作为高纯度孢子粉生产的首选干燥工艺。高真空(15.86 Pa)条件下无论冻干还是室温抽干,虽然孢子粉的含水量(2.2%~8.7%)和含孢量(1270亿~1360亿/g)指标符合生产要求,但活孢率仅62%,说明该菌孢子不适合在高真空条件下干燥。在35℃下烘干24 h所获孢子粉含水量、24 h萌发率和含孢量分别为9.6%、82.8%和1200亿/g,该方法也可在生产中应用,但其活孢率显著低于(P<0.05)低真空低热抽干24 h的孢子粉。  相似文献   

10.
We have introduced a device for selecting Drosophila for increased resistance to very high concentrations of ethanol fumes. This device has enabled us to: 1) select quickly and easily over a thousand flies at a time, and 2) score the knockdown time of every fly in the distribution, while causing very little injury to the flies. A sample of nine west coast populations of Drosophila melanogaster showed a significant trend toward higher knockdown resistance in more northern populations. A population's level of knockdown resistance was virtually uncorrelated with its alcohol dehydrogenase (Adh) allele frequencies. Five of the above nine populations were then subjected to selection for further knockdown resistance. Each population was divided randomly into four groups of 256 flies: two lines to be selected, and two lines to remain unselected as control lines. In every generation each selected line was measured for knockdown resistance, and the last quartile of flies to be knocked down was saved to continue the selection cycle. Population sizes of the selected and unselected lines were all maintained at 256. Realized heritability, based on the responses to selection of the first four generations, was calculated for each selected line. The five populations were significantly heterogeneous for heritability estimates; the average heritability of the five populations pooled was 0.143 ± 0.019. Over the course of twelve generations, the ten selected lines increased their knockdown times by an average factor of 2.40. Before selection, the five populations were heterogeneous for knockdown resistance, and resistance was greatest among the most northern populations. The amount of change of knockdown resistance over the course of selection was also correlated with latitude: the most southern population increased its knockdown time by a factor of 2.23, and the most northern population increased it by a factor of 2.55. After ten generations of selection, the cline of knockdown resistance was about 4.5 times as steep as that before selection. Small phenotypic differences among populations before selection were thus exaggerated by the action of selection. The differences among populations in their rates of response to selection were attributed to genetic differences that existed before selection. The pattern of change of Adh frequencies over the course of selection was very inconsistent, both among and within populations. From this inconsistency of change of Adh alleles with selection, and the lack of correlation between Adh frequencies and knockdown resistance before selection, we concluded that Adh frequency changes could not have had much effect on the responses of the selected lines.  相似文献   

11.
12.
Antarctic phocid seals and particularly the crabeater (Lobodon carcinophagus) have been observed to display a diurnal cycle in their propensity to haul out on pack ice where they are visible for census. The fact that they are not visible for much of the 24-h period means that density estimates made over broad geographic areas at various times of the day statistically confound this cycle with geographic variability. Limitation of census observations to times of peak haulout results in extreme logistical difficulties and/or considerable reduction in sample size upon which to base population estimates. Reduced sample size results in high variability in population estimates and broad confidence bands. To develop a model with which to correct density estimates for variability due to diurnal cycle, a series of stationary censuses at fixed locations in the Antarctic continental ice pack was made over significant fractions of several days. A unimodal polynomial model for the observed density variation in any one location was statistically significant; a similar model combining multiple locations with densities standardized to peak daily values was also significant. The latter model was used to make corrections for time of day to density estimates in three test data sets taken over broad geographic areas of the Antarctic. Statistical simulation (bootstrap) methods were used to determine if variances of corrected density estimates were lower than those based on uncorrected observations taken only during the peak haulout times of the day. Results were that 95% interval estimates for corrected densities were narrowed to between 40% and 61% of the uncorrected estimates. While there are additional possible sources of variation in haulout tendency, pending further data collection and analyses, the model developed represents a considerably more precise methodology than either averaging over haulout variability or limiting observations to peak daily periods.  相似文献   

13.
STATISTICAL ANALYSES FOR R-INDEX   总被引:1,自引:0,他引:1  
R‐index is an important statistic for testing and measuring product effects. The validation and merits of R‐index are to a great extent due to the fact that it is closely related to the famous Mann–Whitney U statistic. Based on this fortunate relationship, statistical analyses for R‐index are explored. The statistical analyses include estimations of R‐index and its null and nonconditional variances with and without assuming continuity of data; difference and similarity tests using R‐index; powers and sample sizes for the tests; linking R‐index with Thurstonian δ (or d′). The new techniques developed in the paper extend greatly the original R‐index analysis for categorical ratings data. It is expected that the recognition of the profound theoretical origin of R‐index and the available statistical analyses for R‐index will provide the impetus for the resurgence of interest in using R‐index in sensory and consumer researches.  相似文献   

14.
A review of the use of blood transfusions used in a small community hospital over a two-year period revealed a high incidence of instances in which the clinical record did not show essential need for the procedure. Educational efforts in hospital staff meetings resulted in some improvement in this respect during the two-year period. Of single unit transfusions given during the first year, 80 per cent were deemed to have been nonessential; during the second year, 52 per cent.Methods which will reduce the use of blood except when it is essential are (1) continuation of staff education; (2) providing the staff with accurate methods of measurement of blood volume and of monitoring blood loss; (3) use of a separate blood transfusion chart in the patient''s hospital record; and (4) establishment of a hospital transfusion committee to review the criteria in all cases in which blood is transfused.  相似文献   

15.
目前一般较大的湖泊水库放养鱼类的回捕率颇低,逃鱼是重要原因之一。为了确定拦鱼用的网和栅所应采取的规格,测量了2,227尾(3—16厘米)鲢、鳙、草、青鱼种的全长,最大周长、头宽、颅宽的各个数值,推算出全长与最大周长、头宽、颅宽的迥归方程式及它们的95%的可信限。通过实验,观察到在流水条件下,鱼种能溯水穿越较自身最大周长为小的拦网网目或较头宽为小的拦栅栅距而逃逸。作者称这种能力为“穿拦系数”(用Kg 或Kp 表示)。并测出在武昌东湖某些生活污水进水口处,1973年3—4月份白鲢鱼种的穿拦系数按Kg 计算为1.5,按Kp 计算为1.2。作者建议在静水或出水口处,设置拦鱼用的拦网的网目长度不得超过所投放色种的最大周长的95%的可信限的下限的1/2,各种拦栅的栅距不得超过鱼种的头宽的95%可信限的下限。而在流水条件下,在确定所应采取的拦网网目或拦栅栅距时,还应该考虑“穿拦系数”在内。文末附有检索表,列举了鲢、鳙、草、青鱼种(3—16厘米)相应于全长值的最大周长值、头宽值、颅宽值以及它们的95%可信限的上限和下限的各个数值,供确定拦网网目和拦栅栅距的规格时参考。    相似文献   

16.
RECOGNITION MEMORY FOR ODORS   总被引:2,自引:2,他引:0  
Recognition tests demonstrated unique features of odor memory.The forgetting curve over a span of one month showed a veryslow decay from an initial performance of 85% correct recognition,a finding that contrasts with the rapid decay for stimuli presentedto other sense modalities. The variables of labelling, codability,serial position, and retention interval had little or no effecton performance. Even the variables of familiarity and pleasantness,salient aspects of odor experience, had no effect on recognition.Hence, the connection between linguistic processing and odorrecognition is weak. * This research supported by grant ES-00592 from the NationalInstitutes of Health.  相似文献   

17.
—A specific radioimmunoassay (RIA) for myelin basic protein is described which is sensitive to 10−9 g of basic protein. The amount of basic protein detected in isolated myelin by the RIA and by SDS-gel electrophoresis and spectrophotometric quantitation agree to within experimental error. In contrast to isolated myelin, the major portion of the basic protein in fresh tissue is not accessible to its antibody. It is shielded from its antibody in a complex which is disrupted by heat, organic solvents, and various detergents. Maximum antibody binding was obtained with tissue heated to 100°C for 10 min. It is possible to calculate that the RIA quantitatively detects basic protein in boiled tissue. Boiled adult rat brain contains approximately 2·5 μg of basic protein/mg wet wt of cerebral cortex. The antibody to basic protein has no capacity to bind non-neural tissues.  相似文献   

18.
Using a model system of 3mM NaCl and purified water, predictions were made for subjects’ability to discriminate the odd sample in a set of nine triadic tasting sequences associated with the triangle test. With such individual triads rather than triangular testing protocols which involve more than one triad, it was found necessary to modify the regular Sequential Sensitivity Analysis. The modification required a consideration of sensory adaptation effects caused by repeated tasting of the same stimulus in some of the sequences. Further confirmation was also obtained for the order of magnitude of signal strengths of water and NaCl stimuli tasted after water or NaCl prerinses.  相似文献   

19.
To help ensure the ethical conduct of research, many have recommended educational efforts in research ethics to investigators and members of research ethics committees (RECs). One type of education activity involves multi‐day workshops in research ethics. To be effective, such workshops should contain the appropriate content and teaching techniques geared towards the learning styles of the targeted audiences. To ensure consistency in content and quality, we describe the development of a curriculum guide, core competencies and associated learning objectives and activities to help educators organize research ethics workshops in their respective institutions. The curriculum guide is divided into modular units to enable planners to develop workshops of different lengths and choose content materials that match the needs, abilities, and prior experiences of the target audiences. The content material in the curriculum guide is relevant for audiences in the Middle East, because individuals from the Middle East who participated in a Certificate Program in research ethics selected and developed the training materials (e.g., articles, powerpoint slides, case studies, protocols). Also, many of the activities incorporate active‐learning methods, consisting of group work activities analyzing case studies and reviewing protocols. The development of such a workshop training curriculum guide represents a sustainable educational resource to enhance research ethics capacity in the Middle East.  相似文献   

20.
A line-transect survey specifically designed to estimate vaquita (Phocoena sinus) abundance over its entire range was carried out by three boats in the summer of 1997. There was a total of 125 sightings of vaquita groups, mainly due to the use of large 25 ± 150 binoculars, which were seven times more effective in detecting vaquitas than hand-held 7 ± binoculars. Results confirmed that the range of the vaquita is restricted to the northwestern corner of the Gulf of California, Mexico, but that the boundaries of the Upper Gulf of California and Colorado River Delta Biosphere Reserve do not correspond well with the distribution of vaquitas. The shallow water north of the town of San Felipe was found to have a higher density of animals than had been indicated by previous surveys. The total population size was estimated to be 567 animals, with a 95% confidence interval from 177 to 1,073. This estimate is an improvement over previous estimates, which had low numbers of sightings, relied on parameters taken from other species, and/or did not cover all areas where vaquitas could potentially be found. The 1997 estimate was more than twice the 1993 estimate, but there are several reasons why the numbers cannot be directly compared, and it should not be concluded the population is increasing. This first complete estimate of vaquita abundance can be a beginning for the recovery of this highly endangered species.  相似文献   

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