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1.
The purpose of this study was to evaluate a new method showing how custom foot orthoses (CFO) improve dynamics of plantar loading. The method is based on the probability distribution of peak pressure time series and is quantified using the Regression Factor (RF). RF is a least square regression slope between the experimentally observed plantar pressure magnitude probability distribution and a modeled Gaussian shape. Plantar pressure data from a randomized controlled trial of 154 participants with painful Pes Cavus were retrospectively re-analyzed. The participants were randomized to an active treatment group given CFO or a control group given sham orthoses. The location of 2(nd) Peak pressure as a percentage of stance time (P(Loc2)) and its magnitude (P(M2)) was also calculated. In addition, plantar pressure data were collected on 23 healthy volunteers with normal foot alignment and no foot pain. Results demonstrated Pes Cavus had a significantly lower RF than healthy participants (0.30 v. 0.51; p<10(-7)). P(M2) was reduced in both active and control groups. However, RF and the P(Loc2) were only changed in the active group (p<0.005) without any significant change in the control group (p>0.5). This study suggests that painful Pes Cavus alters the shape of probability distribution of plantar loading during walking and CFO are an effective therapeutic solution that can significantly improve it. Further use of the RF index and 2(nd) peak pressure location as an outcome measure for treatment of foot and ankle deformities is suggested.  相似文献   

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A new technique for the establishment of a permanent laboratory culture of Chirono-mus riparius is described. Larvae and pupae were reared in plastic tanks containing tap water, filamentous algae and a commercially prepared fishfood. The tanks were aerated, maintained at a constant temperature of 24°C and subjected to a constant lighting regime of 13 h of light followed by 11 h of darkness. Adults flew freely in a modified handling box, mated, and oviposited on strips of filter paper placed in the plastic tanks containing the aquatic stages. It has proved unnecessary to change the water or medium, which has saved both time and effort. Moreover, larvae established themselves in ail parts ofthe alga, and therefore more could be kept in each tank than when, as in previous methods, they are provided only with a substratum on the floor of the container.  相似文献   

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Based on the hypothesis that diabetic foot lesions have a mechanical etiology, extensive efforts have sought to establish a relationship between ulcer occurrence and plantar pressure distribution. However, these factors are still not fully understood. The purpose of this study was to simultaneously record shear and pressure distributions in the heel and forefoot and to answer whether: (i) peak pressure and peak shear for anterior-posterior (AP) and medio-lateral (ML) occur at different locations, and if (ii) peak pressure is always centrally located between sites of maximum AP and ML shear stresses. A custom built system was used to collect shear and pressure data simultaneously on 11 subjects using the 2-step method. The peak pressure was found to be 362 kPa ± 106 in the heel and 527 kPa ± 123 in the forefoot. In addition, the average peak shear values were higher in the forefoot than in the heel. The greatest shear on the plantar surface of the forefoot occurred in the anterior direction (mean and std. dev.: 37.7 ± 7.6 kPa), whereas for the heel, peak shear the foot was in the posterior direction (21.2 ± 5 kPa). The results of this study suggest that the interactions of the shear forces caused greater "spreading" in the forefoot and greater tissue "dragging" in the heel. The results also showed that peak shear stresses do not occur at the same site or time as peak pressure. This may be an important factor in locating where skin breakdown occurs in patients at high-risk for ulceration.  相似文献   

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A simple technique has been developed for establishing stable gradients of a substance in agar. The technique involves the creation of a spherically symmetric concentration profile in which concentration varies inversely with the distance from the source and is independent of the diffusion coefficient of the substance. It has been shown that the gradients established with this technique are stable for at least 190 h. and, on a theoretical basis, they can be kept stable for more than 1000 h. Time-variant gradients can also be established, if desired, using the same system and limiting either the source or the agar sink. It must be emphasized that a stable gradient cannot be obtained by using a shallow agar layer as a sink. The use of such conditions (e.g. the agar in a standard petri dish) can result only in time-variant gradients. The solution to the diffusion equation in a spherically symmetric system establishes the expected concentration profile, the basis for adjusting it, and the parameters that control the behavior of the system. Some useful applications for examining chemotaxis on a solid surface as well as possible further developments are discussed.  相似文献   

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In this article, three cases in which free medial plantar perforator flaps were successfully transferred for coverage of soft-tissue defects in the fingers and foot are described. This perforator flap has no fascial component and is nourished only by perforators of the medial plantar vessel and a cutaneous vein or with a small segment of the medial plantar vessel. The advantages of this flap are minimal donor-site morbidity, minimal damage to both the posterior tibial and medial plantar systems, no need for deep dissection, the ability to thin the flap by primary removal of excess fatty tissue, the use of a large cutaneous vein as a venous drainage system, a good color and texture match for finger pulp repair, short time for flap elevation, possible application as a flow-through flap, and a concealed donor scar.  相似文献   

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A method for recovering dermatoglyphic data from tamarin cadavers is described. The method involves the complete removal of the palmar and plantar pads with no destruction to the underlying skeletal elements. Once recovered, the pads are stored in a formalin solution. The stored pads of 213 individuals have remained in a good state of preservation for dermatoglyphic analysis for over four years.  相似文献   

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A wide range of habitats, both terrestrial and marine littoral, were sampled in an area between Pensacola and Tallahassee. Enchytraeids were present in all moist or wet soils and in marine habitats enriched by organic matter but were absent or rare in very dry soils, saturated or flooded substrates and clean intertidal sand. Between 70 and 75 species were distinguished of which 50–55 are new to North America and about 25 are probably new to science. The genera represented are the same as those occurring in Western Europe but their relative importance differs and there are some tropical elements. The number of species occurring in terrestrial sites was greater than recorded in similar surveys in southwestern France and Ireland (approximately the same-sized area, number of sites and size of sample), but the number of species per sample was lower than in either of the other countries. It is concluded that species distribution in western Florida is very patchy. Possible reasons for this patchiness are discussed.  相似文献   

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Critical oxygen pressure (P(C)) is used in respiratory physiology to measure the response to hypoxia. P(C) defines the partial pressure of oxygen (Po(2)) at which an oxygen regulator switches to a conformer. However, not all animals show such clear patterns in oxygen consumption rate (Mo2), and there are many methods for determining P(C). This study assesses two methods that determine regulatory ability and four that calculate P(C). A new method, the regulation index (RI), assigns to an animal a relative measure of regulatory ability by calculating the area under the Mo2 versus Po(2) curve that is greater than a linear trend. The six methods are applied to developmental Mo2 data of two amphibians, Pseudophryne bibronii and Crinia georgiana. The four methods used to determine P(C) produced similar results but failed to identify the increase in regulation on hatching in C. georgiana or the greater regulation in larval C. georgiana compared with P. bibronii. Of the two methods that evaluated regulation, only the RI satisfactorily represented the entire range of Po(2). The RI is advantageous because it has clearly defined limits and does not constrain data to fit any single pattern. The RI can be used in concert with P(C), which can be easily calculated during the RI analysis, to provide a clearer definition of the Mo2 response to environmental Po(2).  相似文献   

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Prolactin (PRL) has been reported to be a possible mediator in the estradiol (E2)-induced inhibition of the pituitary-testicular axis. In order to better characterize the role of PRL, we studied the action of chronic hypoprolactinemia on this E2 inhibitory effect, using a genetically hypoprolactinemic rat (IPL nude). Normal and IPL nude adult male rats were injected either with vehicle or with E2 valerianate (4 mg/rat) once a week for 2 weeks. Rats were decapitated 7 days after the last injection. Results showed that E2 increased, similarly in both strains, pituitary weight and serum PRL levels. Serum testosterone values were reduced by 96% in both strains. However, testis weight was significantly reduced by 30% in normal rat, while in IPL nude rat, no significant decrease was observed. PRL binding sites, expressed as fmol/mg protein, were reduced in normal rat by 40%. No decrease was found in IPL nude rat. The dissociated E2 action observed in IPL nude rat suggested that only testicular growth inhibition could be mediated by PRL and confirm that testosterone level decrease could be due to a direct action of E2 on Leydig cells.  相似文献   

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On soils differing in total Cd concentration, organic matter content and pH, but with the same compost treatment, a significant linear relation was found between the calculated Cd2+ concentration of the soil solution and the Cd concentration of lettuce grown under field conditions. The Cd2+ concentration was calculated with the equation for the exchange reaction between Cd2+ and Ca2+.  相似文献   

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Considering the recent advances in and the benefits of DNA microarray technologies, many gene filtering approaches have been employed for the diagnosis and prognosis of diseases. In our previous study, we developed a new filtering method, namely, the projective adaptive resonance theory (PART) filtering method. This method was effective in subclass discrimination. In the PART algorithm, the genes with a low variance in gene expression in either class, not both classes, were selected as important genes for modeling. Based on this concept, we developed novel simple filtering methods such as modified signal-to-noise (S2N') in the present study. The discrimination model constructed using these methods showed higher accuracy with higher reproducibility as compared with many conventional filtering methods, including the t-test, S2N, NSC and SAM. The reproducibility of prediction was evaluated based on the correlation between the sets of U-test p-values on randomly divided datasets. With respect to leukemia, lymphoma and breast cancer, the correlation was high; a difference of >0.13 was obtained by the constructed model by using <50 genes selected by S2N'. Improvement was higher in the smaller genes and such higher correlation was observed when t-test, NSC and SAM were used. These results suggest that these modified methods, such as S2N', have high potential to function as new methods for marker gene selection in cancer diagnosis using DNA microarray data. AVAILABILITY: Software is available upon request.  相似文献   

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A field study of mandrill was carried out from 1979 to 1983 in Cameroon for 27 months. Group size of mandrills ranged from 15 to 95 and composition was estimated by direct and indirect observations. The ratio of group size to one adult male was 13.9, larger than other baboon species except the drill. Solitary males were seen. The mandrill may have two types of groups: one-male and multi-male. The multi-male group was observed to split into subgroups, one of which was sometimes a one-male group. The multi-male subgroup was assumed to be composed of several one-male groups. The home range area of mandrills was estimated to be at least 5 km5 to 28 km2. Their large home range size could be related to their characteristic feeding pattern in the forest.  相似文献   

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In this study, an automated surface plasmon resonance (SPR)-based biosensor was compared with a quartz crystal microbalance (QCM) biosensor. The two biosensor systems were used for characterizing a site-directed monoclonal antibody (mAb), raised against the C-terminal heptapeptide ET-115–21 of the human endothelin (ET-1). The mAb was characterized by its capacity for binding to ET-1, ET-3, Big.ET-122–38, the C-terminal (ET-115–21, ET-116–21, ET-117–21), and six derivates of ET-116–21, each containing a substitution with alanine (Ala) of a single aminoacid from position 16–21, respectively. The mAb reacted well with ET-1 and its fragments ET-115–21, ET-116–21, ET-117–21, but showed only a partial cross-reaction with ET-3, and did not bind human Big.ET-122–38. The Ala substitution on position 16,17, or 19 of ET-116–21 did not affect the antibody binding capacity of the hexapaptide ET-116–21. On the contrary, Ala substitution or Asp18, Ile20 and particularly Trp21, inhibited its immunoreactivity. Thus the C-terminal represents an immunodominant epitope in ET-1 and is important for antibody binding. The SPR and QCM response signals were similar in shape but differing in time scales, reflecting differences in detection mechanisms. With regard to the fundamental problem of comparing different measurement principles, we found a good correlation between results obtained using the BIA technology and the QCM.  相似文献   

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本文以苹果叶螨为研究材料,阐述了应用‘虫(螨)日’建立时间动态经济受害水平的方法。研究表明:第一,由于虫(螨)日指数概括了害虫(或害螨)危害的基本过程,故由虫(螨)日与产量损失率作出的EIL和ET模型将更为可靠;其次,所得EIL和ET不是某时刻的单一虫(螨)口密度指标,而是时间动态的虫(螨)口密度和累积虫(螨)日指数综合指标;第三,这种建模方法不必考虑虫(螨)的自然存活率。  相似文献   

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