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21.
Summary The cat gastrocnemius muscles of one hind leg were stretched sinusoidally with amplitudes between 10 m and 2.5 mm and frequencies between 1 and 30 Hz. The stretch response of deefferented muscle spindle afferents and of Ia-activated cells within Clarke's column were investigated by means of extra-cellular recordings of action potentials. The responses to 20–50 cycles were displayed in impulse patterns (raster diagrams) of the responding action potentials. The impulse patterns of Ia afferents exhibited a high degree of phase-locking (regularity) on the stretch cycle of amplitudes of about 50 m at 3 Hz and all higher amplitudes or frequencies. At comparable stretch parameters the regularity in Ia afferents was 4–6 times larger than in Ia-activated DSCT neurons. The regularity in the DSCT patterns increased with an increase in stretch frequency. The impulse patterns of DSCT cells exhibited a high negative correlation between successive interspike intervals (–0.4 to –0.6) at low stretch frequencies (<3 Hz), which decreased with an increase in stretch frequency.  相似文献   
22.
脑电(Electroencephalography, EEG)和功能磁共振(Functional magnetic resonance imaging, fMRI)技术的结合,可以实现两者优势的互补,获得更加合理的源定位结果.本文报道的是一种将fMRI先验信息结合到脑电源定位中的新方法.在该方法中,先利用SPM方法计算获得fMRI的统计映射参数,然后将基于计算获得的统计参数构造的权矩阵结合到FOCUSS的迭代过程中,对脑电的反演提供具有fMRI先验空间位置信息的约束,提高脑电的源空间定位精度,从而获得更加合理的定位结果.通过对一形状知觉实验fMRI和脑电数据的结合定位分析,结果初步证实了改进方法能获得和生理更加一致的结果.  相似文献   
23.
Multimodal soma diameter spectra for neurones of the cat retinal ganglion cell layer have been represented by three subpopulations of independent, normal diameter distribution. Recurrent computation according to the technique of Vibert and Caille (1978) has extracted best fit populations for samples from various regions of central and peripheral retina. The model subpopulations from all these regions did not differ significantly in their relative proportions or variance. Significant progressive variation between subpopulations representing different regions of retina were observed only in the mean diameter of the and mode cells. The parameters of the mode population were statistically uniform across the retina. The cat retina thus appears to be more homogeneously organized than has been suggested elsewhere.  相似文献   
24.
The incidence of pancreatic adenocarcinoma is increasing and it is usually unresectable at the time of diagnosis. Consequently, fine-needle aspiration biopsy (FNAB) is being used more frequently for diagnosis. The reported sensitivity of diagnosing pancreatic adenocarcinoma by FNAB has varied between 50% and 100%. In an attempt to increase the diagnostic sensitivity, we retrospectively reviewed a series of pancreatic FNABs. Fifteen cytologic criteria were evaluated in 78 patients who had pancreatic FNABs. Of these patients, 49 had primary adenocarcinomas and 29 had benign, non-neoplastic lesions. Using a stepwise logistic regression analysis we identified three key cytologic criteria for this diagnosis. Our study identified anisonucleosis (P = 0.001), large nuclei (P = .007), and nuclear molding (P = .03) as the significant cytologic features for diagnosing pancreatic adenocarcinoma. In combination, these three criteria had a sensitivity of 98% and a specificity of 100%.  相似文献   
25.
Publication Guidelines for Heart Rate Studies in Man   总被引:1,自引:0,他引:1  
Publication guidelines are provided for the collection, quantification, and analysis of heart rate data.  相似文献   
26.
SAGE是集多功能于一体的医学遗传学群体与家系资料计算机分析系统。本文概述SAGE系统的主要功能及应用环境。重点介绍了FCOR2和TDTEX两个功能模块的数学原理和使用方法。应用TDTEX模块 ,我们发现微卫星标记 85ca与小儿失神症存在连锁不平衡 ,提示在该位点附近存在小儿失神症的易感基因  相似文献   
27.
《Value in health》2022,25(1):10-31
Health economic evaluations are comparative analyses of alternative courses of action in terms of their costs and consequences. The Consolidated Health Economic Evaluation Reporting Standards (CHEERS) statement, published in 2013, was created to ensure health economic evaluations are identifiable, interpretable, and useful for decision making. It was intended as guidance to help authors report accurately which health interventions were being compared and in what context, how the evaluation was undertaken, what the findings were, and other details that may aid readers and reviewers in interpretation and use of the study. The new CHEERS 2022 statement replaces the previous CHEERS reporting guidance. It reflects the need for guidance that can be more easily applied to all types of health economic evaluation, new methods and developments in the field, and the increased role of stakeholder involvement including patients and the public. It is also broadly applicable to any form of intervention intended to improve the health of individuals or the population, whether simple or complex, and without regard to context (such as healthcare, public health, education, and social care). This Explanation and Elaboration Report presents the new CHEERS 2022 28-item checklist with recommendations and explanation and examples for each item. The CHEERS 2022 statement is primarily intended for researchers reporting economic evaluations for peer-reviewed journals and the peer reviewers and editors assessing them for publication. Nevertheless, we anticipate familiarity with reporting requirements will be useful for analysts when planning studies. It may also be useful for health technology assessment bodies seeking guidance on reporting, given that there is an increasing emphasis on transparency in decision making.  相似文献   
28.
BackgroundThe greatest risk of infectious disease undernotification occurs in settings with limited capacity to detect it reliably. World Health Organization guidance on the measurement of misreporting is paradoxical, requiring robust, independent systems to assess surveillance rigor. Methods are needed to estimate undernotification in settings with incomplete, flawed, or weak surveillance systems. This study attempted to design a tuberculosis (TB) inventory study that balanced rigor with feasibility for high-need settings.ObjectiveThis study aims to design a hybrid TB inventory study for contexts without World Health Organization preconditions. We estimated the proportion of TB cases that were not reported to the Ministry of Health in 2015. The study sought to describe TB surveillance coverage and quality at different levels of TB care provision. Finally, we aimed to identify structural-, facility-, and provider-level barriers to notification and reasons for underreporting, nonreporting, and overreporting.MethodsRetrospective partial digitalization of paper-based surveillance and facility records preceded deterministic and probabilistic record linkage; a hybrid of health facilities and laboratory census with a stratified sampling of HFs with no capacity to notify leveraged a priori knowledge. Distinct extrapolation methods were applied to the sampled health facilities to estimate bacteriologically confirmed versus clinical TB. In-depth interviews and focus groups were used to identify causal factors responsible for undernotification and test the acceptability of remedies.ResultsThe hybrid approach proved viable and instructive. High-specificity verification of paper-based records in the field was efficient and had minimal errors. Limiting extrapolation to clinical cases improved precision. Probabilistic record linkage is computationally intensive, and the choice of software influences estimates. Record absence, decay, and overestimation of the private sector TB treatment behavior threaten validity, meriting mitigation. Data management demands were underestimated. Treatment success was modest in all sectors (R=37.9%–72.0%) and did not align with treatment success reported by the state (6665/8770, 75.99%). One-fifth of TB providers (36/178, 20%) were doubtful that the low volume of patients with TB treated in their facility merited mastery of the extensive TB notification forms and procedures.ConclusionsSubnational inventory studies can be rigorous, relevant, and efficient in countries that need them even in the absence of World Health Organization preconditions, if precautions are taken. The use of triangulation techniques, with minimal recourse to sampling and extrapolation, and the privileging of practical information needs of local decision makers yield reasonable misreporting estimates and viable policy recommendations.  相似文献   
29.
Interventions from randomised controlled trials can only be replicated if they are reported in sufficient detail. The results of trials can only be confidently interpreted if the delivery of the intervention was systematic and the protocol adhered to. We systematically reviewed trials of anaesthetic interventions published in 12 journals from January 2016 to September 2019. We assessed the detail with which interventions were reported, using the Consolidated Standards of Reporting Trials statement for non-pharmacological treatments. We analysed 162 interventions reported by 78 trials in 18,675 participants. Detail sufficiently precise to replicate the intervention was reported for 111 (69%) interventions. Intervention standardisation was reported for 135 (83%) out of the 162 interventions, and protocol adherence was reported for 20 (12%) interventions. Sixty (77%) out of the 78 trials reported the administrative context in which interventions were delivered and 36 (46%) trials detailed the expertise of the practitioners. We conclude that bespoke reporting tools should be developed for anaesthetic interventions and interventions in other areas such as critical care.  相似文献   
30.
The differential diagnosis of prostatic atypical large gland proliferations includes several benign and malignant entities. This review focusses on issues relevant to the practising pathologist, particularly around areas of controversy such as high-grade prostatic intraepithelial neoplasia (HGPIN) and intraductal carcinoma of the prostate (IDCP). HGPIN is a putative precursor of prostate cancer, but its clinical relevance is as a surrogate marker of unsampled prostate cancer, thereby identifying patients who would benefit from a prompt repeat biopsy. The incidence of missed prostate cancer is much lower in contemporary practice due to pre-biopsy MRI and extended sampling protocols so HGPIN is currently less important. It is however important to distinguish HGPIN from PIN-like carcinoma and IDCP. PIN-like carcinoma is considered a histological subtype/variant of acinar prostate carcinoma and should be graded as Gleason pattern 3. A diagnosis of cribriform HGPIN should not be made in needle biopsies as such a proliferation may represent IDCP. This review discusses controversies related to the diagnosis, reporting and management of IDCP. A personalized approach to management of patients with isolated IDCP in needle biopsies that is based on the histological and radiological features of an individual case is outlined.  相似文献   
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