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1.
A randomized controlled trial was carried out with the purpose to determine the effectiveness of EMG-biofeedback in the treatment of chronically constipated elderly patients with dyssynergic defecation as compared to a control condition characterized by information about the bowel functioning and counseling focused on the behavioural mechanisms involved in the defecation. With this purpose, after an initial assessment period (4 weeks), 30 chronically constipated elderly patients with dyssynergic defecation (11 males, 19 females) were randomly assigned to either EMG-biofeedback group (n = 15) or control group (n = 15). The results shown significant improvements in psychophysiological measures (EMG-activity during straining to defecate and anismus index), as well as in clinical variables (frequency of defecations per week, sensation of incomplete evacuation, difficulty evacuation level and perianal pain at defecation) only in the EMG-biofeedback group. The clinical benefits of this behavioural treatment were maintained at the follow-up period 2 months later.  相似文献   

2.
Abstract The wing-fanning activation response of male Oriental fruit moths (OFM), Grapholita molesta (Busck), in the field to the three-component pheromone containing the female-produced ratio of components (Z8-12:OAc + 6% E8-12:OAc + 3% Z8-12:OH) was compared with the response to blends containing 2,10 and 20% E with 3% OH, and the 6% E blend containing 30 and 100% OH. Comparisons were made over three temperature ranges: 15–17, 20–21 and 26–28oC. Both the maximum response distance and male response specificity were significantly altered by changes in odour quality as well as temperature. For blends containing different Z/E ratios the maximum response distance increased significantly with temperature. Response specificity was most pronounced at the 20–21oC range, with males displaying a lower threshold for the natural 6% E ratio, evidenced by the fact that fewer males responded and at closer distances to the source with off-ratios. At 26–28oC response specificity for the Z/E ratios was much reduced, primarily due to more males activating to off-ratios. With blends containing different proportions of Z8-12:OH in the 6% E blend, increasing temperature increased the maximum response distance for all treatments, but in addition increasing the proportion of OH alone from 3% to 30% significantly increased the maximum response distance over the three temperature ranges tested. This increase occurred without affecting the proportion of responders or the distribution of response distances around the mean value. However, with 100% OH added to the blend, whereas male response was high at 20–21oC, the distribution of response distances was significantly more variable than with 3% or 30%, and male response was eliminated or very low at 15–17oC and 26–28oC. Our results support previous studies showing that peak response levels in this species are dependent on male perception of the natural blend of components, and that males have a high degree of specificity for the qualitative properties of the pheromone. However, the present results also extend those of previous flight tunnel tests in which response specificity was most pronounced in the upwind flight phase of the sequence, by showing that male OFM also display a  相似文献   

3.

Background

It is unclear whether response time is affected by a stimulus cue, such as a light turned on or off, or if there are differences in response to these cues during a muscle contraction task compared with a muscle relaxation task. The objective of this study was to assess the response time of a relaxation task, including the contraction portion of the task, to a stimulus of a light turned on or off. In addition, we investigated the effect of the pre-contraction level on the relaxation task.

Results

Contraction response time was significantly shorter during the light-on status than during the light-off status (P <0.01), and relaxation response time in each maximum voluntary contraction was significantly longer during the light-on status than during the light-off status (P <0.01). The relaxation response time became longer in order of 25% to 75% maximum voluntary contraction regardless of light-on or -off status, and was significantly longer than the contraction response time (P <0.05-0.01).

Conclusions

This study found that as the contraction level increased, the relaxation response time became longer than the contraction response time regardless of light status. However, contraction response time or relaxation response time findings were opposite to this during the light-on status and light-off status: contraction response time became shorter in the light-on status than in the light-off status and relaxation response time became longer in the light-on status than in the light-off status. These results suggest that the length of each response time is affected by motor control in the higher order brain and involves specific processing in the visual system.  相似文献   

4.
The aim of the study was to estimate efficiency of the strength training protocol designed to improve maximal voluntary contraction without development of muscle hypertrophy. The principal difference between chosen training protocol and classical strength training was that the number of training movements during training session was increased to improve the motor skill, and rest periods between the training movements were increased as well to minimize damage of muscle fibers, which is one of the factors inducing muscle hypertrophy. Knee extensors of right leg in 11 physically active males were trained 4 times a week for 4 weeks. Evaluation of force-velocity characteristics with simultaneous recording of EMG-activity was performed in both trained and untrained legs immediately before, during and several times after the 4 wks training period. Before and after training the size and contractile properties ofipsi- and contralateral knee extensors were evaluated by MRI and twitch interpolation technique. Maximum strength gains after 4 week of training were about 17% in both trained and untrained legs and did not differ significantly from each other. A noticeable increase of EMG-activity during contraction was also found for both legs after 4-wks training period. The observed changes were not accompanied by any significant changes of muscle size, demonstrating the "neural" nature of the training effects.  相似文献   

5.
目的:探讨生物反馈训练辅助治疗梗阻性便秘患者对粪便性状、排便时间与排便频度的影响。方法:选取我院收治的90例梗阻性便秘患者,根据随机数字表法分为3组,A组接受常规治疗,B组于常规治疗基础上进行固定式生物反馈训练(FBF),C组于常规治疗基础上进行自适应式生物反馈训练(ABF),比较3组治疗前后肛直肠功能、粪便性状、排便时间、排便频度和临床疗效。结果:治疗后,直肠肛门压力梯度:A组B组C组(P0.05),矛盾性收缩率:A组B组C组(P0.05),B组与C组肛管静息压、直肠肛门抑制反射阈值显著小于A组(P0.05),且肛管松弛率显著大于A组(P0.05);C组粪便性状4~7型占比明显高于其余两组(P0.05),且B组4~7型占比明显高于A组(P0.05);排便时间:A组B组C组(P0.05),排便频度:A组B组C组(P0.05);C组总有效率显著高于A组与B组(P0.05)。结论:生物反馈训练尤其是ABF可有效改善梗阻性便秘患者肛直肠功能,在改善粪便性状、缩短排便时间、增加排便频度上具有明显优势,可获得更好的临床疗效。  相似文献   

6.
The effect of the selective 5-hydroxytryptamine (5-HT)(3) receptor agonist YM-31636 (2-(1H-imidazol-4-ylmethyl)-8H-indeno[1,2-d]thiazole monofumarate) on gut motility of fed ferrets was investigated. YM-31636 (0.1 mg/kg p.o.) induced a giant migrating contraction (GMC)-like, high-amplitude, ungrouped colonic contraction although it did not change the basal colonic motility pattern. This GMC-like contraction was always accompanied by defecation. Both GMC-like contraction and defecation were inhibited with the selective 5-HT(3) receptor antagonist ramosetron. YM-31636 affected gastric, duodenal and ileal motility pattern only slightly. These results suggest that 5-HT(3) receptor agonists such as YM-31636 are useful in treating constipation since they facilitate GMC-like contractions and defecation without undesired changes in gut motility pattern.  相似文献   

7.
Two cvs of alfalfa ( Medicago sativa L.), Gilboa and Moapa 69, were inoculated in glasshouse pots with three arbuscular mycorrhizal (AM) fungi to investigate the efficacy of mycorrhizas with respect to the extent of colonization and sporulation. Paspalum notatum Flugge also was inoculated to describe fungal parameters on a routine pot culture host. Percentage root length of P. notatum colonized by Glomus mosseae (Nicol. & Gerd.) Gerdemann & Trappe, Glomus intraradices Schenck & Smith, and Gigaspora margarita Becker & Hall increased from 10 to 21 wk, and all fungi sporulated during that period. In alfalfa, only colonization by G. intraradices increased over that time period, and it was the only fungus to sporulate in association with alfalfa at 10 wk. Glomus mosseae did not sporulate after 16–21 wk despite having colonized 30–35% of the root length of both alfalfa cvs. In vitro experiments in which Ri T-DNA-transformed roots of alfalfa were inoculated with AM fungi showed normal mycorrhizal formation by G. intraradices and a hypersensitivity-like response to Gi. margarita . Colonized cells became necrotic, and HPLC analysis indicated increased concentrations of phenolics and isoflavonoids in these root segments. These data strongly support the existence of a degree of specificity between AM fungi and host that might rely on specific biochemical regulatory processes initiated in the host as a result of the attempts at colonization by the fungus.  相似文献   

8.
The amino-acid sequences of soluble, globular proteins must have hydrophobic residues to form a stable core, but excess sequence hydrophobicity can lead to loss of native state conformational specificity and aggregation. Previous studies of polar-to-hydrophobic mutations in the β-sheet of the Arc repressor dimer showed that a single substitution at position 11 (N11L) leads to population of an alternate dimeric fold in which the β-sheet is replaced by helix. Two additional hydrophobic mutations at positions 9 and 13 (Q9V and R13V) lead to population of a differently folded octamer along with both dimeric folds. Here we conduct a comprehensive study of the sequence determinants of this progressive loss of fold specificity. We find that the alternate dimer-fold specifically results from the N11L substitution and is not promoted by other hydrophobic substitutions in the β-sheet. We also find that three highly hydrophobic substitutions at positions 9, 11, and 13 are necessary and sufficient for oligomer formation, but the oligomer size depends on the identity of the hydrophobic residue in question. The hydrophobic substitutions increase thermal stability, illustrating how increased hydrophobicity can increase folding stability even as it degrades conformational specificity. The oligomeric variants are predicted to be aggregation-prone but may be hindered from doing so by proline residues that flank the β-sheet region. Loss of conformational specificity due to increased hydrophobicity can manifest itself at any level of structure, depending upon the specific mutations and the context in which they occur.  相似文献   

9.
Genetic Analysis of Defecation in Caenorhabditis Elegans   总被引:9,自引:2,他引:7       下载免费PDF全文
J. H. Thomas 《Genetics》1990,124(4):855-872
Defecation in the nematode Caenorhabditis elegans is achieved by a cyclical stereotyped motor program. The first step in each cycle is contraction of a set of posterior body muscles (pBoc), followed by contraction of a set of anterior body muscles (aBoc), and finally contraction of specialized anal muscles that open the anus and expel intestinal contents (Exp). By testing existing behavioral mutants and screening for new mutants that become constipated due to defects in defecation, I have identified 18 genes that are involved in defecation. Mutations in 16 of these genes affect specific parts of the motor program: mutations in two genes specifically affect the pBoc step; mutations in four genes affect the aBoc step; mutations in four genes affect the Exp step; and mutations in six genes affect both aBoc and Exp. Mutations in two other genes affect the defecation cycle period but have a normal motor program. Sensory inputs that regulate the cycle timing in the wild type are also described. On the basis of the phenotypes of the defecation mutants and of double mutants, I suggest a formal genetic pathway for the control of the defecation motor program.  相似文献   

10.
The objective of this study was to evaluate people attending a primary health clinic in Rio de Janeiro, Brazil for immunoreactivity to five Mycobacterium tuberculosis antigens, as these antigens are markers of immune response and factors associated with active TB. The serum antibody titers of different categories of patients (defined by microbiological and radiological characteristics and by response to therapy on follow‐up) to 38 kDa, 16 kDa, MPT64, ESAT‐6 and MT10.3 antigens were determined blind with ELISA. Positive tests to each antigen were defined with ROC analysis. OR were calculated for factors associated with humoral response in patients with active TB. A total of 201 patients underwent serological testing. Patients with confirmed active TB responded more frequently to MPT64 (44%), 16 kDa (37.7%) and 38 kDa (36.1%). ESAT‐6 and MT10.3 were also able to distinguish people in TB groups from controls. TB infected subjects responded less frequently to ESAT‐6 and MT10.3 (3.7% and 11%, respectively). Sensitivity and specificity to all antigens combined were 58.4% and 60.7%, respectively. Reactivity to 38 kDa and to MPT64 was more likely among alcohol users OR 2.61 (95%CI;1.05–6.94) and OR 3.27 (95%CI;1.33–8.15), respectively. 16 kDa antigen elicited a more protective response among smokers, OR 0.29 (95%CI; 0.10–0.83). It was concluded that reactivity to all antigens tested represented markers of active disease. ESAT‐6 and MT10.3 could not be identified as markers of TB infection in this community. Sensitivity was higher to all antigens combined, but at a cost of lower specificity. Interestingly, among factors associated with positive immunoreactivity, alcohol use and smoking seem to polarize the humoral response in different directions. This finding deserves further investigation.  相似文献   

11.
Objectives:  This prospective study was undertaken to evaluate nuclear matrix protein (NMP22) compared to urine cytology in the detection of bladder cancer and also to determine whether indexing suspicious cytology to NMP22 could enhance the clinical utility of cytology.
Methods:  Cytological findings of voided urine collected prior to a cystoscopic biopsy were correlated with urine NMP22 assay in 46 patients attending the urology clinic in Mubarak Al-Kabeer Hospital. The patients were clinically categorized into newly diagnosed cases of transitional cell carcinoma (TCC), recurrent TCC, TCC in remission and controls.
Results:  Using histological diagnosis as the gold standard the sensitivity and specificity of NMP22 were 78% and 43% respectively and of cases with malignant urine cytology were 30% and 87% respectively. If suspicious and malignant cytology were combined as positive results the sensitivity increased significantly to 87% while the specificity decreased but not significantly to 74%. Suspicious or malignant cytology enhanced by positive NMP22 gave a sensitivity of 70% and specificity of 87% neither of which was significantly different from cytology alone. There were three false positive cases on cytology and 13 false positive cases on NMP22 assay. There were three false negative cytology and five false negative NMP22 cases but only one was false negative for both, resulting in a high sensitivity (96%) but low specificity (30%) if either positive NMP22 or malignant or suspicious cytology was taken as a positive result.
Conclusion:  Combining NMP22 with malignant or suspicious cytological result improved sensitivity for the detection of bladder cancer but with a major decrease in specificity, suggesting a potential role in screening rather than diagnosis.  相似文献   

12.
We present direct evidence for a change in protein structural specificity due to hydrophobic core packing. High resolution structural analysis of a designed core variant of ubiquitin reveals that the protein is in slow exchange between two conformations. Examination of side-chain rotamers indicates that this dynamic response and the lower stability of the protein are coupled to greater strain and mobility in the core. The results suggest that manipulating the level of side-chain strain may be one way of fine tuning the stability and specificity of proteins.  相似文献   

13.
Ecological immunology attempts to explain variation in immune function. Much of this work makes predictions about how potential hosts should invest in overall immunity. However, this ‘overall’ perspective under-emphasizes other critical aspects, such as the specificity, inducibility and timing of an immune response. Here, we investigate these aspects by examining gene regulation across several immune system components in both male and female Drosophila melanogaster prior to and after mating. To elucidate potentially important temporal dynamics, we also assayed several genes over time. We found that males and females emphasized different components of their immune system, however overall investment was similar. Specifically, the sexes emphasized different gene paralogues within major gene families, and males tended to invest more in gram-negative defence. By contrast, the inducibility of the immune response was both transient (lasting approx. 24 hours) and equal between the sexes. Furthermore, mating tended to induce humoral gene upregulation, while cell-mediated genes were unaffected. Within the humoral system, gram-negative bacterial defence genes exhibited a greater inducibility than those associated with fungal or gram-positive bacterial defence. Our results suggest that variation in the effectiveness of the immune response between the sexes may be driven by differences in emphasis rather than overall investment.  相似文献   

14.
The Hoffmann (H) reflex and motor (M) response were studied in soleus and gastrocnemius during voluntary contraction in eight male volunteers. Aims: To determine if the strength of spindle input to the muscles is the same. To assess if the M response size changes during contraction. Results: The size of the maximum M response (M max) changed during contraction in each subject. Hence, all H reflex measurements were normalized to the M max at each level of contraction for each subject. The largest H/M max was bigger in soleus than gastrocnemius at every contraction level. The overall largest H/M max for soleus (97%) and gastrocnemius (55%) were achieved at 40 and 100% maximum voluntary contraction (MVC), respectively. Conclusion: Soleus receives greater spindle feedback than the gastrocnemius both at rest and during voluntary contraction.  相似文献   

15.
Lateral radiographs of the rectum and anus were taken in 90 children with chronic idiopathic constipation. A computer program was developed to obtain an objective quantitative assessment of the anorectal angle; it averaged 120° at rest, decreased during forceful anal contraction and increased during defecation. It was noted that 24% of the children, when asked to defecate, decreased their anorectal angle as normally observed during forceful anal contraction and, that 21% when asked to contract the anus, increased the angle as if they were defecating. This ‘sphincteric disobedience’ is probably of major clinical relevance to an understanding of the symptoms of these patients.  相似文献   

16.
The morphology of a sex pheromone-producing gland found in the abdomen of Drosophila grimshawi males was studied by light and electron microscopy. This gland, consisting of two intra-anal lobes, contains cells that resemble those of other insect pheromone glands. However, in contrast to many other insect pheromone glands that release pheromone through the cuticle, cells of the intra-anal lobes secrete into a canaliculi-duct system that empties into the anal region. The liquid secretory product flows along the surface of the intra-anal lobes and is brushed onto the substrate by fingerlike projections on the lobes' surfaces.  相似文献   

17.
Factors influencing the social acceptability of large carnivore behaviours   总被引:2,自引:1,他引:1  
A survey on attitudes toward large carnivores was conducted in a representative sample of the Norwegian population (n = 3134). People were asked about the acceptability of carnivores living in remote wilderness, close to where people live, killing livestock, killing pets, or threatening humans. Large differences in acceptability appeared across the five situations. Wolves and bears were less acceptable than lynx and wolverines when observed close to where people live. Negative associations were found between acceptability and lack of personal control, economic loss, and respondents' age. Acceptability was higher among males than among females, and higher among urban than among rural residents. The results showed that general measures of attitudes alone toward large carnivores were of limited value in wildlife management. The situational and social specificity of these attitudes should be given more attention.  相似文献   

18.
Calcium signaling represents one of the most important signaling cascades in cells and regulates diverse processes such as exocytosis, muscle contraction and relaxation, gene expression and cell growth. G protein-coupled receptors (GPCRs) are the most important family of receptors that activate calcium signaling. Since calcium signaling regulates a large number of physiological responses, it is intriguing that how changes in cytosolic calcium levels by a wide range of stimuli lead to signal-specific physiological responses in the cellular interior. In order to address this issue, we have analyzed temporal calcium profiles induced by two GPCRs, the serotonin1A and purinergic receptors. In this work, we have described a set of parameters for the analysis of calcium transients that could provide novel insight into mechanisms responsible for maintaining signal specificity by shaping calcium transients. An interesting feature of calcium signaling that has emerged from our analysis is that the profile of individual transients in a calcium response could play an important role in maintaining downstream signal specificity. In summary, our analysis offers a novel approach to identify differences in calcium response patterns induced by various stimuli.  相似文献   

19.
Immobilized Candida antarctica lipase B, Novozym® 435, was used in the esterification of adipic acid and alcohols with different chain lengths (C1–C18). Optimum conditions for the synthesis of adipate esters were obtained using response surface methodology (RSM) with respect to important reaction parameters including time, temperature, substrate molar ratio and amount of enzyme. Alcohol chain length specificity of the enzyme in the synthesis of adipate esters was also determined. Minimum reaction time (215 min) for achieving maximum ester yield was obtained for butyl alcohol. Methanol required an increased time (358 min) and enzyme amount (10.2%, w/w) for attaining maximum yield. The maximum required temperature and time of 65°C and 523 min, respectively, were obtained for the synthesis of dioctadecyl adipate. The results demonstrate that alcohol chain length is a determining parameter in optimization of the lipase-catalyzed synthesis of adipate esters. Reactions under optimized conditions yielded a high percentage of esterification (>97%). The optimum conditions can be used to scale up the process.  相似文献   

20.
The C. elegans defecation cycle is characterized by the contraction of three distinct sets of muscles every 50 s. Our data indicate that this cycle is regulated by periodic calcium release mediated by the inositol trisphosphate receptor (IP3 receptor). Mutations in the IP3 receptor slow down or eliminate the cycle, while overexpression speeds up the cycle. The IP3 receptor controls these periodic muscle contractions nonautonomously from the intestine. In the intestinal cells, calcium levels oscillate with the same period as the defecation cycle and peak calcium levels immediately precede the first muscle contraction. Mutations in the IP3 receptor slow or eliminate these calcium oscillations. Thus, the IP3 receptor is an essential component of the timekeeper for this cycle and represents a novel mechanism for the control of behavioral rhythms.  相似文献   

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