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991.
The effect of capsaicin-induced stimulation of afferent neurons on peristalsis and the possible neural mediators involved in this action were examined in the guinea-pig isolated ileum. The intraluminal pressure threshold for eliciting peristaltic waves was used to quantify facilitation (decrease in threshold) or inhibition (increase in threshold) of peristalsis. Capsaicin (0.1–1 M) caused an initial short-lasting stimulation of peristalsis followed by a prolonged inhibition of peristaltic activity. Capsaicin (1 M) was ineffective when the gut segments had been pretreated with 3.3 M capsaicin, which is indicative of an afferent neuron-dependent action of the drug. In contrast, the abolition of peristalsis caused by a high concentration of capsaicin (33 M) was fully reversible on removal and reproducible on readministration of capsaicin, a feature characteristic of a nonspecific depression of smooth muscle excitability. Baseline peristalsis and the excitatory/inhibitory effect of capsaicin (1 M) on peristalsis remained unaltered by a combination of the tachykinin NK1 receptor antagonist ( + )-(2S, 3S)-3-(2-methoxybenzylamino)-2-phenyl piperidine (CP-99,994; 0.3 M) and the tachykinin NK2 receptor antagonist L(-)-N-methyl-N[4-acetylamino-4-phenyl-piperidino-2-(3,4-dichlorophenyl)butyl]-benzamide (SR-48,968; 0.1 M). Further experiments, performed in the presence of a low concentration of atropine (10 nM) showed that the catcitonin gene-related peptide (CGRP) antagonist human -catcitonin gene-related peptide (8–37) [hCGRP (8–37); 10 M] attenuated the delayed inhibitory effect of capsaicin on peristalsis, but did not influence baseline peristaltic activity and the capsaicin-induced facilitation of peristalsis. Blockade of nitric oxide (NO) synthesis by N G-nitro-l-arginine methylester (l-NAME, 300 M) facilitated baseline peristaltic activity and reduced the delayed inhibition of peristalsis caused by capsaicin (1 M) without affecting the initial peristalsis-stimulating action of capsaicin. The effects of l-NAME were prevented by l-arginine (1 mM). The data of the current study indicate that capsaicin-sensitive afferent neurons do not participate in the neural pathways subserving peristalsis in the guinea-pig small intestine, but modulate peristaltic activity upon stimulation with capsaicin. The initial stimulant action of capsaicin on peristalsis is independent of tachykinins acting via NK1 or NK2 receptors, while the delayed capsaicin-induced depression of peristalsis involves CGRP and NO.  相似文献   
992.
Simulation studies were conducted to assess the relative merits of different nonrandom sampling strategies for the selection of sibling pairs for genotyping in the attempt to locate individual loci (QTLs) contributing to variation in human quantitative traits. For a constant amount of variation contributed by a QTL (25% of the total) the frequencies and dominance relationships of a trait increasing allele were varied. Three strategies for selection of pairs for genotyping were based on the phenotypic values of the siblings: Concordant sib pairs (CSP) are pairs in which both individuals exceed a given threshold value; discordant sib pairs (DSP) are pairs in which one member exceeds a given upper threshold and the other is below a specified lower threshold; and most similar pairs (MSP) are pairs selected for falling below a specified percentile ranking of the within-pair mean square for the quantitative trait. Tests for linkage with markers at 1, 2, 5, 10, and 20 cM from each of the QTLs were conducted for each of the selected samples and compared with tests based on the regression, in the entire sample, of within pair variation on the proportion of alleles identical by descent (IBD) at each marker locus. Tests for the effect of the increasing allele at the QTL (candidate gene) were also conducted for the DSP pairs. No single nonrandom selection procedure yields as much as half the information realized in the total sample. However, a combined strategy which involves genotyping the 5% of MSP and DSP for the upper and lower quintiles of values of the quantitative trait (a further 3% of the sample approximately) yields lod scores which are usually more than 65% of the values realized for the entire sample. Tests comparing the proportion of increasing alleles in high- and low-scoring siblings from DSP samples are uniformly very powerful for detecting candidate loci. Even when it is not possible to measure the entire range of the phenotype with uniform precision, some attempt to differentiate among individuals in a common unaffected class of individuals can lead to considerable increase in power.  相似文献   
993.
The cerebral representation of space depends on the integration of many different sensory inputs. The vestibular system provides one such input and its dysfunction can cause profound spatial disorientation. Using positron emission tomography (PET), we measured regional cerebral perfusion with various vestibular stimulations to map central vestibular projections and to investigate the cerebral basis of spatial disorientation. We showed that the temporoparietal cortex, the insula, the putamen, and the anterior cingulate cortex are the cerebral projections of the vestibular system in man and that the spatial disorientation caused by unilateral vestibular stimulation is associated with their asymmetric activation.  相似文献   
994.
目的 探讨上肢机器人虚拟情景训练联合头针对脑卒中后认知功能障碍的影响。 方法 选取脑卒中后认知功能障碍(PSCI)患者90例,按照随机数字表法分为对照组、头针组、综合组,每组30例。对照组给予常规认知和康复训练,头针组给予常规认知和康复训练联合头针治疗,综合组给予常规认知和康复训练、头针治疗和上肢机器人虚拟情景训练。治疗前和治疗4周后(治疗后),采用简易精神量表(MMSE)和蒙特利尔认知评估量表(MoCA)评估3组患者认知功能,同时采用改良的Barthel指数(MBI)评估3组患者日常生活活动能力。 结果 治疗后,3组患者的MMSE评分、MoCA评分和MBI评分较组内治疗前均明显改善(P<0.05)。头针组治疗后,仅MMSE评分和MBI评分显著优于对照组治疗后(P<0.05)。综合组治疗后的MMSE评分为(22.03±0.96)分,MoCA评分为(15.07±1.48)分,MBI评分为(73.10±8.45)分,均显著优于头针组和对照组治疗后(P<0.05)。 结论 上肢机器人虚拟情景训练联合头针可显著改善PSCI患者的认知功能,并提高其日常生活活动能力。  相似文献   
995.
目的 通过分析郑州大学附属郑州中心医院参加过腹腔镜技能培训的普外科青年医师的腹腔镜胆囊切除术学习曲线,探讨腹腔镜虚拟现实模拟培训的意义。方法 将青年外科医师50人分为两组,干预组参加虚拟现实模拟培训,对照组参加传统腹腔镜临床培训。培训完成后,在高年资拥有丰富腹腔镜手术经验医师的监督下完成30例腹腔镜胆囊切除术。应用CUSUM分析法,根据完成率、手术评分和手术时间绘制学员的手术学习曲线。x为手术例数,k为斜率。计算k=0时的x值,比较两组学员的手术学习曲线和术中评分。采用SPSS 23.00进行t检验和卡方检验。结果 干预组与对照组分别在x=19.24±0.39、x=21.72±0.73时跨过手术学习曲线,差异有统计学意义(P<0.01);干预组与对照组显露胆囊部分得分分别为(10.82±2.73)、(9.71±2.69)(t=4.61,P<0.01);解剖胆囊三角得分分别为(12.59±3.12)、(8.87±2.99)(t=6.21,P<0.01);剥离胆囊得分分别为(10.69±3.38)、(8.80±3.55)(t=3.10,P<0.01)。结论 虚拟现实模拟培训可以促进腹腔镜培训的基本技能转化为临床操作技能,可促进普外科青年医师成长。  相似文献   
996.
该文提出了当前涉及整个卫生工作的十大关系,并就如何正确认识、正确处理这十大关系发表了自己的见解。  相似文献   
997.
本文回顾了国内护理人员信息系统研究的背景和现状,介绍了作者自行研制的护理人员信息管理系统的结构和功能,并将其用于护士继续教育和规范化培训的管理过程,已取得较好成果。护理人员信息管理系统的开发与应用旨在适应未来护理的发展需求,促进护理管理的现代化。  相似文献   
998.
此专家系统在修善顾博士行医经验和治疗原则的基础上 ,利用多媒体技术 ,结合声频、视频、图片和文本以治疗乳腺增生病。在医疗设计中 ,着重于顾博士的类型识别要点和乳腺增生病的自然规律。尤其 ,此医疗设计阐明了顾博士所总结的有价值的治疗经验 ,以突出此专家系统的科学性、实用性和可操作性。笔者曾将此专家系统应用于临床 1 30份病例的治疗中。其结果表明此专家系统的临床治疗正确率与顾博士临床治疗相对照达 98%。  相似文献   
999.
ObjectiveTo determine the circadian influence on sound sensitivity produced by temporal hearing deprivation in healthy normal human subjects.DesignParticipants underwent bilateral earplugging before completion of anthropometry, the author's developed questionnaire, the Hamilton Anxiety and Depression Inventory, pure tone audiometry (PTA), stapedial reflex thresholds (SRT), distortion products otoacoustic emissions input/output (DPOAE-I/O), and uncomfortable loudness levels (ULLs). Afterward, the participants were randomly divided into group A, starting at 8:00 a.m. and finishing at 8:00 p.m., and group B, starting at 4:00 p.m. and ending at 4:00 a.m. Serum cortisol levels and audiological test results were obtained at the beginning and end of the session and 24-h free urinary cortisol levels were measured.Study sampleThirty healthy volunteers.ResultsPTA was 2.68 and 3.33 dB HL in groups A and B, respectively, with no statistical difference between them. ULLs were significantly lower in group A compared to group B, with an average of 8.1 dB SPL in group A and 3.3 dB SPL in group B (p < 0.0001). A SRT shift was observed in group A, with no difference in group B, and a night shift in DPOAE-I/O in group B.ConclusionsReduced loudness tolerance is demonstrated during daytime hearing deprivation in contrast to nighttime; this may be due to increased central gain in the awake cortex.  相似文献   
1000.
A new multidimensional movement analysis system was used to record limb tremor over six degrees-of-freedom, and signal processing techniques were explored to develop a suitable classification method to distinguish between different types of tremor. The specific aims were to investigate the ability of the system to screen for differences between normal subjects and a group of neurological patients, and then to differentiate between three diagnostic groups of patients.

Postural tremor at the hand was recorded in normal subjects (n=24) and patients with essential tremor (n=21), multiple sclerosis (n=17) and parkinsonism (n=19). Data were collected using a 3Space Fastrak® (Polhemus, Inc.) over six degrees-of-freedom (three translational directions and three rotations). Spectral estimates produced measures of tremor frequency and amplitude. Mathematical models of the data, using autoregressive modelling and K-nearest neighbour classification, produced parameters used to classify, (1) the normal subjects and 24 patients (using the three rotational movements), and (2) the three patient groups (using all six movement directions). Results were given in terms of the probability of each subject belonging to the groups being classified.

Tremor frequency and amplitude showed large overlap between the groups. The screening classification produced high probabilities of correctly classifying normal subjects (>70%) and patients (>70%). The diagnostic classification produced clear differences between the patient groups (60% for essential tremor, 80% for multiple sclerosis and 60% for parkinsonism).

The ability of this assessment technique to distinguish between postural tremor in normal subjects and neurological patients suggests that it could be developed as a screening tool. Classification of tremors between the patients groups, with a high degree of sensitivity, indicates the potential for further development of the system as a diagnostic aid.  相似文献   

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