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61.
Low amplitude mechanical noise vibration has been shown to improve somatosensory acuity in various clinical groups with comparable deficiencies through a phenomenon known as Stochastic Resonance (SR). This technology showed promising outcomes in improving somatosensory acuity in other clinical patients (e.g., Parkinson’s disease and osteoarthritis). Some degree of chronic somatosensory deficiency in the knee has been reported following anterior cruciate ligament (ACL) reconstruction surgery. In this study, the effect of the SR phenomenon on improving knee somatosensory acuity (proprioception and kinesthesia) in female ACL reconstructed (ACLR) participants (n = 19) was tested at three months post-surgery, and the results were compared to healthy controls (n = 28). Proprioception was quantified by the measure of joint position sense (JPS) and kinesthesia with the threshold to detection of passive movement (TDPM).The results based on the statistical analysis demonstrated an overall difference between the somatosensory acuity in the ACLR limb compared to healthy controls (p = 0.007). A larger TDPM was observed in the ACLR limb compared to the healthy controls (p = 0.002). However, the JPS between the ACLR and healthy limbs were not statistically significantly different (p = 0.365). SR significantly improved JPS (p = 0.006) while the effect was more pronounced in the ACLR cohort. The effect on the TDPM did not reach statistical significance (p = 0.681) in either group.In conclusion, deficient kinesthesia in the ACLR limb was observed at three months post-surgery. Also, the positive effects of SR on somatosensory acuity in the ACL reconstructed group warrant further investigation into the use of this phenomenon to improve proprioception in ACLR and healthy groups.  相似文献   
62.
Fish larvae abundances, diversity and trophic position across shallow seagrass, coral reef and open water habitats were examined to characterize their distribution in coastal East Africa. Larvae were identified to family and analysed for abundance differences between sites and habitats, trophic level using stable-isotope analysis and parental spawning mode. Abundances differed greatly between sites with the highest numbers of larvae occurring in the open-water and seagrass habitats. Larval fish diversity was high across habitats with 51 families identified with small differences between sites and among habitats. Notably, larvae of abundant large herbivorous fishes present in reef and seagrass habitats were almost completely absent at all sampling locations. In the seagrass, demersal spawned larvae were more abundant compared with the reef and open-water habitats. Stable-isotope analysis revealed that fish larvae have a varied diet, occupying trophic level two to three and utilizing planktonic prey. This study offers new insights into distributional aspects of fish larvae along the East African coast where such information is sparse.  相似文献   
63.
Purpose: The main objective of the present study was to evaluate the effects of laterality discrimination training on neck joint position sense and cervical range of motion (ROM) in patients with chronic non-specific neck pain (NSCNP).

Materials and methods: Forty-eight patients with NSCNP were randomly assigned to the neck group (NG) that observed neck images or the foot group (FG) that observed foot images. Response time, response accuracy, cervical ROM, and joint position error (JPE) were the main variables. The secondary outcome measures included psychosocial variables.

Results: Differences between groups in the cervical ROM for flexion (p?=?.043) were obtained, being NG group the one which obtained greater values. NG showed an improvement in right rotation (p?=?.018) and a decrease in flexion was found in the FG (p?=?.039). In JPE, differences between groups were obtained in the left rotation (p?=?.021) and significant changes were found in the NG for flexion, extension, and left rotation movements (p?<?.05). Moderate associations were found between left and right accuracy regarding to post-intervention flexion and right rotation (r?=?0.46, r?=?0.41; p?<?.05) in NG.

Conclusion: Improvements in cervical range of motion and joint position sense are obtained after the performance of the laterality discrimination task of images of the neck but not the feet. Visualization of images of the painful region presents moderate correlations with the accuracy and response time in the movements of flexion and right rotation.  相似文献   

64.
The vertical foliage distribution of Castanopsis cuspidata (Thunb.) Schottky was examined in trees of various sizes to clarify its variation in relation to tree size and the light environment in a stand. As indices of these parameters, we analyzed crown social position (CSP: percent of stand height) and specific leaf area (SLA). The vertical foliage distribution of trees was expressed by a Weibull function. The variation in the vertical foliage distribution of C. cuspidata could be categorized into three types using crown social position and light environment. In the first type, leaves were concentrated to the top 20% of the tree; such trees are canopy trees that can receive full sunlight. The second type had a large relative crown depth and an asymmetric distribution with the maximum foliage located near the top of the tree; such trees are suppressed trees whose crowns do not receive sufficient light. The third type had a large relative crown depth and a symmetric distribution; such trees occur in high light environments, although their crowns are in the understory layer. The differences in the vertical foliage distribution are related to the strategies used to capture light. Multiple regression analysis showed that CSP and SLA at the top layer of the tree explained successive changes in the vertical foliage distribution. These results will contribute to scaling-up the vertical foliage distribution to the community level in pure stands of C. cuspidata using an individual-based model.  相似文献   
65.
66.
BACKGROUND: Nonsyndromic cleft lip with or without cleft palate, CL(P), is a common human birth defect with a complex unknown genetic cause. The mouse model is the "A/-" strains. Our previous studies mapped two loci: clf1 on Chr11 and clf2 on Chr13--with a strong genetic maternal effect on the level of risk. Here we test the hypothesis that CL(P) is digenic and identify candidate genes for clf1 and clf2. METHODS: We observed E14 CL(P) frequencies in backcross (BC1) embryos from a new cross of A/WySn to AXB-4/Pgn and from test crosses of three new "congenic RI" lines. Using new polymorphic markers from genes and our mapping panels of segregants and RI strains, we identified the candidate genes for clf1 and clf2. We sequenced the coding region of Ptch in A/WySn cDNA. RESULTS: Seventy new BC1 CL(P) segregants (4%) were obtained, as predicted. All three new congenic RI lines homozygous for both clf1 and clf2 had A/WySn-level CL(P) frequencies (10-30%) in test crosses. The clf1 region contains 10 known genes (Arf2, Cdc27, Crhr1, Gosr2, Itgb3, Mapt, Myl4, Nsf, Wnt3, and Wnt9b). The clf2 region contains 17 known genes with human orthologs. Both regions contain additional potential genes. No causal mutation in Ptch coding sequence was found. CONCLUSIONS: In A-strain mice, nonsyndromic CL(P) is digenic, suggesting that nonsyndromic human CL(P) may also be digenic. The orthologous human genes are on 17q (clf1) and 9q, 8q and 5p (clf2), and good candidate genes are WNT3 or WNT9B (17q), and PTCH (9q) or MTRR (5p).  相似文献   
67.
To probe the dynamics and size of lipid rafts in the membrane of living cells, the local diffusion of single membrane proteins was measured. A laser trap was used to confine the motion of a bead bound to a raft protein to a small area (diam < or = 100 nm) and to measure its local diffusion by high resolution single particle tracking. Using protein constructs with identical ectodomains and different membrane regions and vice versa, we demonstrate that this method provides the viscous damping of the membrane domain in the lipid bilayer. When glycosylphosphatidylinositol (GPI) -anchored and transmembrane proteins are raft-associated, their diffusion becomes independent of the type of membrane anchor and is significantly reduced compared with that of nonraft transmembrane proteins. Cholesterol depletion accelerates the diffusion of raft-associated proteins for transmembrane raft proteins to the level of transmembrane nonraft proteins and for GPI-anchored proteins even further. Raft-associated GPI-anchored proteins were never observed to dissociate from the raft within the measurement intervals of up to 10 min. The measurements agree with lipid rafts being cholesterol-stabilized complexes of 26 +/- 13 nm in size diffusing as one entity for minutes.  相似文献   
68.
本文根据系统学原理,提出了建立新类元的依据;并据此从分类和系统发育上论证了近金线属AnchicyclocheilusLietLan独立成属的可能性,认为应将近金线属归于金线属;修订了金线属SinocyclocheilusFang的鉴别特征。  相似文献   
69.
大花黄牡丹分类学地位的研究   总被引:9,自引:0,他引:9  
李嘉珏  陈德忠 《植物研究》1998,18(2):152-155
通过野外调查、引种试验,对大花黄牡丹与黄牡丹的形态特征、生长和繁殖特性进行了综合比较研究,结果表明,二者之间在植株高度、心皮数目、花色、花瓣基部有无棕红斑及繁殖特性等存在明显差异;同时,染色体组型、带型及蛋白亚基构成分析也表明二者之间有明显差异,因此我们认为,大花黄牡丹应上升为种的等级:Paeonia ludlowii(Stern et Taylor)J.J.Li et D.Z.Chen,stat  相似文献   
70.
The fitness costs and benefits at different positions in fishshoals, bird flocks, and insect swarms can be asymmetric; agroup's edge may provide more feeding opportunities, but alsogreater predator risk. Animals make trade-offs between theseselection pressures based on individual differences in traitsincluding satiation level, ability to avoid predators, and sex.Previous studies did not evaluate the impact of sex on grouppositioning in these types of nonhierarchical, nonmating groupscalled congregations. A controlled laboratory experiment wasconducted, using marked whirligig beetles (Coleoptera: Gyrinidae),to test for sexual segregation and why different sexes mightchoose different positions. Soon after a disturbance, malesoften were found at the periphery and females at the centerof groups. There was also an overlying influence of feedingon position; satiated individuals moved toward the center andhungry individuals toward the periphery. Several minutes aftera disturbance, sexual segregation disappeared, but segregationdue to hunger persisted. Sexual segregation in this study wasbest explained by the predator avoidance hypothesis, not theenergy needs hypothesis. Females weighed less than males; thismay make them more at risk to predation because of reduced swimmingspeed or less mechanical protection from their exoskeleton.No difference between the sexes was found in the volume of theirdefensive chemicals. This is one of the first studies to showthat sex influences position of individuals within simple nonmatinggroups (congregations) and suggests that more attention shouldbe given to positional sex differences within shoals, flocks,herds, and swarms.  相似文献   
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