首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献,搜索用时 265 毫秒
1.
Recently, right and left output properties exerted from specific muscle groups have been evaluated using special measurement devices such as an isokinetic dynamometer. However, it remains unclear whether the coach can properly evaluate muscle function corresponding to lateral specificity in athletes. This study aimed to examine the different output properties between the dominant (D) and nondominant (ND) upper limbs as measured by muscle function tests with various muscle contraction patterns. Fifteen right-handed young men participated in this study. Each subject carried out isometric, isokinetic, and isotonic muscle power tests by elbow flexion with right and left arms. When calculating the laterality index, the laterality of the isotonic test (1.17) was the highest. In all tests, significant correlations were found between the measurements of the D and ND limbs. The isometric test was the highest (r = 0.93), followed by the isokinetic test (r = 0.66-0.83) and the isotonic test (r = 0.55). To examine the ratio of the laterality of measurements provided by each muscle function test, each measurement was converted to a standard score (Z-score). There were significant differences between D and ND limbs in the isometric (D:ND = 55.0:45.0) and the isotonic (54.1:45.9) tests but not in the isokinetic test (60°·s?1, 51.4:48.6; 180°·s?1, 50.7:49.2; 300°·s?1, 51.8:48.2). Particularly, the D (right) limb exerted greater muscle power in the isometric and the isotonic tests than in the isokinetic test. Occupational therapists or strength and conditioning professionals should understand that the D-ND differences shown by these muscle function tests may differ because of measurement conditions.  相似文献   

2.
Monthly sexual behavior tests were carried out for 1 yr in a group of 19 male goats (10 Verata breed and 9 Malague?a breed) 12 mo of age. Simultaneously with the tests, 5 blood samples were collected, 2 before and 3 after contact with females, to determine the influence of sexual stimulus on the secretion of testosterone. By means of radioimmunoassay, it was determined that both breeds showed a significant increase in testosterone secretion as a result of the sexual stimulus during increasing daylength (Verata: P<0.01; Malague?a: P<0.05), when testosterone secretion levels prior to the stimulus were the lowest of the year. Moreover, the level of testosterone secretion was higher in the Verata than in the Malague?a breed (P<0.01). A significant though low correlation (P<0.05) between the rise of testosterone levels as a response to sexual stimulus and the degree of sexual behavior in the males was observed in the Verata breed. However, there was no correlation between these factors in Malague?a male goats.  相似文献   

3.
The identification of effective solar protectants for field application of the codling moth, Cydia pomonella (L.), granulovirus (CpGV) is of interest to improve its efficacy and commercial viability as a biological pesticide. We evaluated several materials as potential adjuvants to protect CpGV from ultraviolet degradation. In laboratory tests with a solar simulator (9.36×106 J/m2), the addition of kaolin clay (Surround® WP at 3 and 6%, w/v), a paraffin wax-based emulsion (SPLAT? at 5%, v/v), and a bark extract trans-cinnamaldehyde combined with a film agent (both at 1%, v/v) did not significantly reduce larval entries or increase larval mortality in irradiated apples that were treated with a commercial CpGV product (Cyd-X). In semi-field tests in an apple orchard, a spray-dried lignin formulation containing CpGV (6.57×1012 OBs/ha) and a lignin-based adjuvant used with Cyd-X (both applied at 4.7–5.6 kg lignin/ha) significantly improved residual activity of CpGV compared with Cyd-X alone applied at the same rate. However, the benefits were short lived and could not be detected after 7 days. In orchard tests, we evaluated two additional refined lignin-products (Lignosulfonate and Vanisperse? CB at 5.61 kg/ha) and two particle film materials (kaolin clay, ‘Cocoon?’, and calcium with boron ‘Eclipse?’) as adjuvants for UV protection of Cyd-X (6.57×1012 OBs/ha) in tests against a dense codling moth infestation. Although all virus treatments were highly effective (causing ≥90% larval mortality), no significant effects of the adjuvant treatments could be detected. In these latter tests, the use of a silicone based wetting agent at 0.025% (v/v) may have been beneficial at increasing mortality among older larvae inside the fruit.  相似文献   

4.
This study was designed to examine time-of-day effects on markers of cardiac functional capacity during a standard progressive cycle exercise test. Fourteen healthy, untrained young males (mean?±?SD: 17.9?±?0.7 yrs of age) performed identical maximal cycle tests in the morning (08:00-11:00?h) and late afternoon (16:00-19:00?h) in random order. Cardiac variables were measured at rest, submaximal exercise, and maximal exercise by standard echocardiographic techniques. No differences in morning and afternoon testing values at rest or during exercise were observed for oxygen uptake, heart rate, cardiac output, or markers of systolic and diastolic myocardial function. Values at peak exercise for Vo(2) at morning and afternoon testing were 3.20?±?0.49 and 3.24?±?0.55?L min(-1), respectively, for heart rate 190?±?11 and 188?±?15?bpm, and for cardiac output 19.5?±?2.8 and 19.8?±?3.5?L min(-1). Coefficients of variation for morning and afternoon values for these variables were similar to those previously published for test-retest reproducibility. This study failed to demonstrate evidence for significant time-of-day variation in Vo(2)max or cardiac function during standard progressive exercise testing in adolescent males.  相似文献   

5.
We consider the problem of testing for independence against the consistent superiority of one treatment over another when the response variable is binary and is compared across two treatments in each of several strata. Specifically, we consider the randomized clinical trial setting. A number of issues arise in this context. First, should tables be combined if there are small or zero margins? Second, should one assume a common odds ratio across strata? Third, if the odds ratios differ across strata, then how does the standard test (based on a common odds ratio) perform? Fourth, are there other analyzes that are more appropriate for handling a situation in which the odds ratios may differ across strata? In addressing these issues we find that the frequently used Cochran–Mantel–Haenszel test may have a poor power profile, despite being optimal when the odds ratios are common. We develop novel tests that are analogous to the Smirnov, modified Smirnov, convex hull, and adaptive tests that have been proposed for ordered categorical data. (© 2006 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)  相似文献   

6.
Although diabetic peripheral neuropathy (DPN) and chemotherapy-induced peripheral neuropathy (CIPN) are different disease entities, they share similar neuropathic symptoms that impede quality of life for these patients. Despite having very similar downstream effects, there have been no direct comparisons between DPN and CIPN with respect to symptom severity and therapeutic responses. We compared peripheral nerve damage due to hyperglycemia with that caused by paclitaxel (PAC) treatment as represented by biochemical parameters, diverse sensory tests, and immunohistochemistry of cutaneous and sciatic nerves. The therapeutic effects of alpha-lipoic acid and DA-9801 were also compared in the two models. Animals were divided into seven groups (n?=?7–10) as follows: normal, diabetes (DM), DM?+?alpha-lipoic acid 100?mg/kg (ALA), DM?+?DA-9801 (100?mg/kg), paclitaxel-treated rat (PAC), PAC?+?ALA (100?mg/kg), and PAC?+?DA-9801 (100?mg/kg). The sensory thresholds of animals to mechanical, heat, and pressure stimuli were altered by both hyperglycemia and PAC when compared with controls, and the responses to sensory tests were different between both groups. There were no significant differences in the biochemical markers of blood glutathione between DM and PAC groups (p?>?.05). Quantitative comparisons of peripheral nerves by intraepidermal nerve fiber density (IENFD) analysis indicated that the DM and PAC groups were similar (6.18?±?1.03 vs. 5.01?±?2.57). IENFD was significantly improved after ALA and DA-9801 treatment in diabetic animals (7.6?±?1.28, 7.7?±?1.28, respectively, p?p?>?.05). Sciatic nerves were less damaged in the PAC-treated groups compared with the DM groups with respect to axonal diameter and area (8.60?±?1.14?μm vs. 6.66?±?1.07?μm, and 59.04?±?15.16?μm2 vs. 35.71?±?11.2?μm2, respectively, p?相似文献   

7.
Robert S. Boyd 《Plant and Soil》2007,293(1-2):153-176
Elemental hyperaccumulation may have several functions, including plant defense against natural enemies. A total of 34 studies, including 72 experimental tests, have been conducted to date. At least some tests have demonstrated defense by hyperaccumulated As, Cd, Ni, Se and Zn, but relatively few plant taxa and natural enemies have been investigated. Defense by hyperaccumulated Ni has been shown for most leaf/root chewing herbivores and pathogens tested (20 of 26 tests) but not for herbivores of other feeding modes (1 of 8 tests). Most tests (5 of 6) using Ni concentrations below accumulator levels found no defensive effect, and the single test using plants in the accumulator range also found no effect. For Zn, mixed results have been reported for both hyperaccumulator (3 of 6 tests showed defense) and accumulator levels (3 of 4 tests showed defense). These tests have focused exclusively on leaf chewing/scraping herbivores: no herbivores of other feeding modes, or pathogens, have been tested. Both hyperaccumulator and accumulator concentrations of Se generally have shown defensive effects (12 of 14 tests). Most (75%) of these positive results used plants with accumulator Se concentrations. The three tests of Cd showed defensive effects in two cases, one for hyperaccumulator and one for sub-accumulator Cd concentrations. Arsenic has been tested only once, and was found effective against a leaf-chewing herbivore at a concentration much less than the hyperaccumulator level. Defense studies have used a variety of experimental approaches, including choice and no-choice experiments as well as experiments that use artificial diet or growth media. Investigations of hyperaccumulation as a defense against natural enemies have led to two emerging questions. First, what is the minimum concentration of an element sufficient for defense? Evidence suggests that plants other than hyperaccumulators (such as accumulators) may be defended by elements against some natural enemies. Second, do the effects of an element combine with the effects of organic defensive compounds in plants to produce enhanced joint defensive effects? Recent investigation of this “joint effects hypothesis,” using Ni and secondary plant compounds in artificial insect diet, has demonstrated joint effects. Initial answers to both these questions suggest that defensive effects of elements in plants are more widespread than previously believed. These results also suggest an evolutionary pathway by which elemental hyperaccumulation may have evolved from accumulation. In this “defensive enhancement” scenario, defensive benefits of elevated levels of elements may have led to stepwise increases in element concentrations that further magnified these benefits. This series of steps could have led to increased accumulation, and ultimately hyperaccumulation, of elements by plants.  相似文献   

8.
Models of post-traumatic osteoarthritis where early degenerative changes can be monitored are valuable for assessing potential therapeutic strategies. Current methods for evaluating cartilage mechanical properties may not capture the low-grade cartilage changes expected at these earlier time points following injury. In this study, an explant model of cartilage injury was used to determine whether streaming potential measurements by manual indentation could detect cartilage changes immediately following mechanical impact and to compare their sensitivity to biomechanical tests. Impacts were delivered ex vivo, at one of three stress levels, to specific positions on isolated adult equine trochlea. Cartilage properties were assessed by streaming potential measurements, made pre- and post-impact using a commercially available arthroscopic device, and by stress relaxation tests in unconfined compression geometry of isolated cartilage disks, providing the streaming potential integral (SPI), fibril modulus (Ef), matrix modulus (Em), and permeability (k). Histological sections were stained with Safranin-O and adjacent unstained sections examined in polarized light microscopy. Impacts were low, 17.3?±?2.7 MPa (n?=?15), medium, 27.8?±?8.5 MPa (n?=?13), or high, 48.7?±?12.1 MPa (n?=?16), and delivered using a custom-built spring-loaded device with a rise time of approximately 1 ms. SPI was significantly reduced after medium (p?=?0.006) and high (p<0.001) impacts. Ef, representing collagen network stiffness, was significantly reduced in high impact samples only (p?相似文献   

9.
The present study discusses two variants of linear logistic models for polytomous variables for ?unordered”? and for ?ordered”? categories (polydimensional and one-dimensional model). The ML-estimation equations and the possibilities to test the validity of the model are given for both. A test for goodness-of-fit (external validity) and a test for equality of the parameter estimates for split data (interval validity) are suggested. In addition, statistical tests for the significance of individual parameters on the basis of the information matrix and likelihood ratio tests for one or more parameters are described. The presentation is completed by an empirical example from the area of audiology.  相似文献   

10.
In biological nitrogen removal, application of the autotrophic anammox process is gaining ground worldwide. Although this field has been widely researched in last years, some aspects as the accelerating effect of putative intermediates (mainly N?H? and NH?OH) need more specific investigation. In the current study, experiments in a moving bed biofilm reactor (MBBR) and batch tests were performed to evaluate the optimum concentrations of anammox process intermediates that accelerate the autotrophic nitrogen removal and mitigate a decrease in the anammox bacteria activity using anammox (anaerobic ammonium oxidation) biomass enriched on ring-shaped biofilm carriers. Anammox biomass was previously grown on blank biofilm carriers for 450 days at moderate temperature 26.0 (±0.5) °C by using sludge reject water as seeding material. FISH analysis revealed that anammox microorganisms were located in clusters in the biofilm. With addition of 1.27 and 1.31 mg N L?1 of each NH?OH and N?H?, respectively, into the MBBR total nitrogen (TN) removal efficiency was rapidly restored after inhibitions by NO??. Various combinations of N?H?, NH?OH, NH??, and NO?? were used as batch substrates. The highest total nitrogen (TN) removal rate with the optimum N?H? concentration (4.38 mg N L?1) present in these batches was 5.43 mg N g?1 TSS h?1, whereas equimolar concentrations of N?H? and NH?OH added together showed lower TN removal rates. Intermediates could be applied in practice to contribute to the recovery of inhibition-damaged wastewater treatment facilities using anammox technology.  相似文献   

11.
Adrenal masses discovered incidentally during imaging studies - adrenal incidentalomas (AIs) - are common and prompt investigations to exclude secretory lesions and malignancy. Their best management strategy is unknown. Our objectives were to identify all outcomes of AI investigation in a UK centre and to assess the performance of the 2?mg low dose (LDDST) and 1?mg overnight dexamethasone (ODST) suppression tests in this setting. Out of 125 patients referred to our centre between 2005 and 2009 with AIs, 16 (12.8%) were diagnosed with secretory adrenal adenomas. 24 patients (23%) failed to suppress on LDDST or ODST using a serum cortisol cut-off of 50?nmol/l for both tests; in 12 this was due to false positive results. 5 patients were diagnosed with adrenal Cushing's syndrome and 7 with subclinical hypercortisolism. The use of a higher post LDDST (83?nmol/l) or ODST (138?nmol/l) cortisol cut-off would have resulted in missing 1 patient with Cushing's syndrome and 4 with subclinical hypercortisolism or 2 patients with Cushing's syndrome and 1 with subclinical hypercortisolism, respectively. In patients who had both tests, the ODST systematically resulted in higher post-test cortisol values compared with the LDDST. The adenoma diameter correlated with and was predictive of the post LDDST cortisol. Our results indicate that altering the post dexamethasone cut-off in accordance to published guidelines changes the performance of the suppression tests. The ODST may result in higher post-test cortisol levels compared to LDDST when used in patients with AIs.  相似文献   

12.
The mechanical behavior of human femurs has been described in the literature with regard to torsion and tension but only as independent measurements. However, in this study, human femurs were subjected to torsion to determine if a simultaneous axial tensile load was generated. Fresh frozen human femurs (n=25) were harvested and stripped of soft tissue. Each femur was mounted rigidly in a specially designed test jig and remained at a fixed axial length during all experiments. Femurs were subjected to external and internal rotation applied at a constant angulation rate of 0.1 deg/s to a maximum torque of 12?N?m. Applied torque and generated axial tension were monitored simultaneously. Outcome measurements were extracted from torsion-versus-tension graphs. There was a strong relationship between applied torsion and the resulting tension for external rotation tests (torsion/tension ratio=551.7±283.8?mm, R(2)=0.83±0.20, n=25), internal rotation tests (torsion/tension ratio=495.3±233.1?mm, R(2)=0.87±0.17, n=24), left femurs (torsion/tension ratio=542.2±262.4?mm, R(2)=0.88±0.13, n=24), and right femurs (torsion/tension ratio=506.7±260.0?mm, R(2)=0.82±0.22, n=25). No statistically significant differences were found for external versus internal rotation groups or for left versus right femurs when comparing torsion/tension ratios (p=0.85) or R(2) values (p=0.54). A strongly coupled linear relationship between torsion and tension for human femurs was exhibited. This suggests an interplay between these two factors during activities of daily living and injury processes.  相似文献   

13.
An original ligand (Lac-10-Chol) designed to interact with asialoglycoprotein receptors to potentially target hepatocyte was synthesised by grafting a lactose head to a cholesteryl structure, which was then included in liposomes. Preliminary formulation tests led to the selection of conventional formulations based on soybean phosphatidylcholine/cholesterol/DOTAP (± DOPE) (± Lac-10-Chol) that present reproducible absolute entrapment value (1.45?±?0.10%), with a size of 109?±?7?nm and a slight positive charge (3.77?±?1.59?mV). Cell viability (via the MTT test), expressed as the percentage of nontreated cells in HepG2 cells, was very close to the control. Internalization tests evidenced an intracellular penetration of fluorescent liposomes, but no specific ligand effect was demonstrated (P?>?0.05). Nevertheless, regarding the adenosine triphosphate (ATP) assay, a slight increase was obtained with liposome loaded with ATP incorporating Lac-10-chol after 24 hours (P?<?0.05).  相似文献   

14.
Defined serological blood tests of deceased cornea donors are required to minimize the risk of viral infections of a transplant recipient as much as possible. Haemolysis, autolysis and bacterial contamination, may produce significant changes of post-mortem blood samples, which may lead to false serological test results. Pre- and post-mortem findings from the same cornea donors of the University Tissue Bank of the Charité in the years 2004-2009 (n?=?487) were retrospectively analyzed and compared. The test results from pre-mortem blood samples were defined as the reference for the post-mortem blood test. Of 487 cornea donors, there were a total of 21 cases (4.3?%) with discrepancies between serological test results from pre- and post-mortem blood samples. Of these, 7 values referred to the HBsAg-testing, 3 to the anti-HBs-, 1 to the anti-HBcIgG?+?IgM-, 1 to the anti-HCV-, 4 to the anti-HIV 1/2- and 5 to the TPLA-findings. False negative results within post-mortem serology occurred in 4 of 487 cases (0.8?%). False positive results within the post-mortem blood samples occurred at a much more frequent rate, with 17 of 487 cases (3.5?%). Discrepancies between serological pre- and post-mortem blood tests occur mainly due to the use of non-validated test systems. Therefore, it seems reasonable to test pre- and post-mortem blood samples serologically, whenever possible, at the same time, regardless of the sample age. Positive results, regardless of the sample type, should always be retested with validated confirmation tests (e.g. NAT), in order to differentiate between false and true positive results.  相似文献   

15.
Who owns your body and parts removed from it? Can you legally sell your bodily material – or information derived from it? Can you legally prevent other people gaining access to your excised bodily material, including your blood relatives who might need your tissue or genetic information for their own genetic tests? What legal remedies are there if people take or use your bodily material without your consent? And why are the answers to these questions vitally important for scientists?  相似文献   

16.
? Apart from their antifungal role, plant defensins have recently been shown to be involved in abiotic stress tolerance or in inhibition of root growth when added in plant culture medium. We studied the subcellular localization of these proteins, which may account for these different roles. ? Stable and transient expression of AhPDF1.1::GFP (green fluorescent protein) fusion proteins were analysed in yeast and plants. Functional tests established that the GFP tag did not alter the action of the defensin. Subcellular localization of AhPDF1.1 was characterized: by imaging AhPDF1.1::GFP together with organelle markers; and by immunolabelling AhPDF1.1 in Arabidopsis halleri and Arabidopsis thaliana leaves using a polyclonal serum. ? All our independent approaches demonstrated that AhPDF1.1 is retained in intracellular compartments on the way to the lytic vacuole, instead of being addressed to the apoplasm. ? These findings challenge the commonly accepted idea of secretion of defensins. The subcellular localization highlighted in this study could partly explain the dual role of plant defensins on plant cells and is of major importance to unravel the mechanisms of action of these proteins at the cellular level.  相似文献   

17.
The aim of this study was to examine the intraobserver reliability of a posturographic assessment in patients with low back pain. We investigated 24 symptomatic subjects with defined low back pain (mean: 57.9?years) and a pair-matched control group including 24 asymptomatic persons (mean: 58.1?years). Each participant underwent two measurements on a posturographic device (32?Hz sampling rate) based on the Interactive Balance System (time interval: 7?d). Test procedure consisted of tests on solid ground with eyes open (1) and eyes closed (2). Data analysis included parameters of motor output and a frequency band analysis. Reliability tests were realized using by intraclass correlations (ICC). Coefficients of ICC ranged from 0.36 (95% CI: 0.01–0.73) to 0.94 (95% CI: 0.86–0.97) in both test positions. For 69% (11/16) of the investigated parameters a high level (ICC?>?0.75) of intraobserver reliability was reached. Based on the results, the posturographic measurement system used in this study seems to be appropriate for use in longitudinal study designs in an orthopaedic setting.  相似文献   

18.
Texture and Microstructure of Gelatin/Corn Starch-Based Gummy Confections   总被引:3,自引:0,他引:3  
Texture of gummy gels prepared with gelatin and acid modified corn starch (AMCS) was quantified by instrumental techniques and the gel microstructure was examined by confocal laser scanning microscopy (CLSM) and scanning electron microscopy (SEM). Gelatin:AMCS gummy gels were divided in two groups: Group 1, containing different gelatin (0?C10?wt%) and AMCS (0?C10?wt%) concentrations, totalizing 10?wt% solids; and Group 2, which was prepared with a fixed gelatin concentration (8?wt%) and varied AMCS concentrations (0?C5?wt%). All gummy gels were formulated with maltitol syrup and xylitol, shaped in cylindrical molds and submitted to instrumental texture profile analysis (TPA) tests and colorimetric analysis. Group 1 pure starch gels (10?% AMCS) presented the highest stringiness and adhesiveness. In samples of Group 2 the introduction of AMCS dramatically changed the structure of the gelatin gels. Thermodynamic incompatibility was evident even at the lowest AMCS concentration. Moreover, increasing AMCS concentrations lead to an increase in the number of hollow zones including starch granules inside them. In addition, introduction of AMCS in the samples of Group 2 caused an increase in hardness and opacity and a decrease in stringiness and adhesiveness. On the other hand, results from TPA tests showed that the addition of AMCS to gelatin gels in suitable proportions can be a feasible alternative in the formulation of gummy confections.  相似文献   

19.
Why review statistical tests of neutrality at a time when pan-selectionists and pan-neutralists alike seem to have been replaced by weak selectionists? First, we still don't actually know how variation is maintained at the molecular level; and second, tests of neutrality have a utility for evolutionary biologists beyond the neutralist/selectionist debate. New tests and variations on the existing tests are arising practically every month. From the complementary viewpoints of an empiricist and a theoretician, we sample the recent literature on tests of statistical neutrality and discuss the motivations, applications, assumptions, interpretations and future directions of these tests.  相似文献   

20.
Microbiologically influenced corrosion (MIC) is a major problem in various industries such as oil and gas, and water utilities. Billions of dollars are lost to microbiologically influenced corrosion (MIC) each year in the US. The key to MIC control is biofilm mitigation. Sulfate-reducing bacteria (SRB) are often the culprits. They are also involved in souring and biofouling. SRB biofilms are notoriously difficult to eradicate. Due to environmental concerns and increasing costs, better biocide treatment strategies are desired. Recent studies suggested that D: -tyrosine and some other D: -amino acids may signal biofilm dispersal. Experimental results in this work indicated that D: -tyrosine is an effective biocide enhancer for tetrakis hydroxymethyl phosphonium sulfate (THPS) that is a green biocide. Desulfovibrio vulgaris (ATCC 7757) was used in biofilm prevention and biofilm removal tests. It was found that 100?ppm D: -tyrosine alone and 50?ppm THPS alone were both ineffective against the SRB biofilm. However, when 1?ppm D: -tyrosine was combined with 50?ppm THPS, the synergy between the two chemicals successfully prevented the establishment of the SRB biofilm on C1018 mild steel coupon surfaces in batch treatment tests. It also eradicated established SRB biofilms from coupon surfaces in both 1 and 3-h shock treatment tests.  相似文献   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号