史载祥治疗难治性发热三法

难治性发热病机较为复杂,肿瘤发热在难治性发热中具有代表性.史载祥教授认为,运用经方治疗难治性发热的关键在于精准辨证.临证时当从整体出发,明确邪正关系,处方之时当谨守病机,方证对应,既遵循中医学整体观念、辨证施治的基本特点,又强调更为精准的辨证与个体化治疗.史教授创立清解三阳退热法、培土生金宣热法、灌肠逐瘀导热法,治疗难...     

5种复合树脂不同水浴时间的压缩强度体外实验评价

目的　评价5种市场常用的复合树脂固化后经不同水浴时间压缩强度的变化。方法　将5种复合树脂（Nulite F,Filtek Z250,Filtek P60,Beautifil II,Charisma）分别制作24个圆柱体试件并固化,每种复合树脂再分为4组,每组6个样本,其中1组浸泡于37 ℃蒸馏水浴1 h,另外3组分别接受蒸馏水浴1 d、7 d和30 d,测试各组的压缩强度值。测试结果以One-way ANOVA和LSD法统计学检验。结果　水浴1 d后,各品牌复合树脂的压缩强度值均有明显提高。树脂试件经1 h水浴时,Filtek Z250的平均压缩强度最高,Beautifil II其次;1 d和7 d水浴后,Filtek P60 和Filtek Z250的压缩强度最高,Beautifil II居中;30 d水浴后,Filtek Z250的压缩强度最高。结论　Filtek P60和Filtek Z250具有较好的抗压性能,复合树脂充填修复一段时间后压缩强度值才能达到最大。     

Normal values for finger systolic blood pressures in males and females

Objective

To compare finger systolic blood pressures in males and females and in younger and older persons and provide normal values for all four fingers in younger and older males and females.

Methods

Eighty healthy subjects participated in the study: 20 males and 20 females aged 20–30 years, and 20 males and 20 females aged 55–65 years. Finger systolic blood pressures (FSBPs) were measured using strain-gauge plethysmography following local cooling at 30 and 10°C in accord with International Standard 14835-2. The FSBPs were measured simultaneously in the thumb and the four fingers of the dominant hand and the percentage changes in finger systolic blood pressures (%FSBPs) due to the cold provocation were calculated.

Results

The median finger systolic blood pressures increased with increasing age in both females and males, with the increase highly significant at 30°C but not at 10°C. The %FSBPs were not significantly affected by the age of males, but were significantly lower in older females than younger females. The FSBPs were lower in females than in males at 30°C but there was no significant difference between genders at 10°C. The %FSBPs were higher in younger females than younger males, but only significantly higher in the middle finger and there were no significant differences between the genders in the older age group. There were only minor differences between the four fingers in the FSBPs at 30 and 10°C. The %FSBPs across the four fingers were similar in the younger subjects and in the older females, but varied with finger in the older males.

Conclusion

Although there are some differences in the %FSBPs associated with age, gender, and finger, the differences may be sufficiently small to use a single value criterion when deciding on abnormalities in FSBP associated with cold provocation for persons aged 20–65 years.

     

A longitudinal study of finger systolic blood pressure and exposure to hand-transmitted vibration

Objectives

To investigate prospectively the relation between vibration-induced white finger (VWF), exposure to hand-trasmitted vibration (HTV) and the cold response of digital arteries in users of vibrating tools.

Methods

Two-hundred and sixteen HTV workers and 133 control men of the same companies underwent initially a medical examination and a standardised cold test with measurement of the change in finger systolic blood pressure (FSBP) after finger cooling from 30 to 10°C. They were re-examined 1 year later. Tool vibration magnitudes were expressed as frequency-weighted and unweighted r.m.s. accelerations. From the vibration magnitudes and exposure durations, alternative measures of cumulative vibration dose were calculated for each HTV worker, according to the expression: $ \text{dose} = \sum a_i^m t_iObjectives To investigate prospectively the relation between vibration-induced white finger (VWF), exposure to hand-trasmitted vibration (HTV) and the cold response of digital arteries in users of vibrating tools. Methods Two-hundred and sixteen HTV workers and 133 control men of the same companies underwent initially a medical examination and a standardised cold test with measurement of the change in finger systolic blood pressure (FSBP) after finger cooling from 30 to 10°C. They were re-examined 1 year later. Tool vibration magnitudes were expressed as frequency-weighted and unweighted r.m.s. accelerations. From the vibration magnitudes and exposure durations, alternative measures of cumulative vibration dose were calculated for each HTV worker, according to the expression: , where a _i is the acceleration magnitude on tool i, t _i is the lifetime exposure duration for tool i, and m = 0, 1, 2 or 4. Results Among the HTV workers, the initial prevalence and the 1-year incidence of VWF were 18.1 and 1.7%, respectively. At the first examination, the HTV workers with moderate or severe score for VWF showed a significantly increased cold reaction in the fingers when compared with the controls and the HTV workers with no vascular symptoms. At the follow-up, the controls, the asymptomatic HTV workers, and the prevalent cases of VWF did not show significant changes in the cold response of digital arteries. A deterioration of cold-induced digital vasoconstriction was found in the incident cases of VWF. In the HTV workers, vibration doses with high powers of acceleration (i.e., with m > 1) were major predictors of the vasoconstrictor response to cold at the follow-up examination. Conclusions The measurement of FSBP after local cooling may be a helpful objective test to monitor prospectively the change in vibration-induced vascular symptoms. The findings of this longitudinal study suggest a dose–effect relationship between cold-induced digital arterial hyperresponsiveness over time and measures of cumulative vibration exposure. In the controls, the cold response of the digital arteries was stable over 1-year follow-up period. Work presented at the second International Workshop 2006 on Diagnosis of Hand–Arm Vibration Syndrome in G?teborg, Sweden.     

Eye bank issues: II. Preservation techniques: warm versus cold storage

Most of the tissue used for penetrating keratoplasty is issued through eye banks that store the corneoscleral button either in hypothermic storage at 2–6°C or in organ culture at 31–37°C. These two preservation techniques differ in technical aspects, tissue evaluation possibilities, storage time and microbiological safety. Hypothermic storage is simple and requires little expensive equipment. In general a pre-storage evaluation of the endothelium is performed by specular microscopy and storage time is usually around 7–10 days. Organ culture is a relatively complicated technique requiring more expertise and well-equipped facilities. Evaluation of the endothelium is not only performed before storage, but is routinely performed after storage through the use of light microscopy. With organ culture the allowed storage period is longer, up to four weeks. The vulnerability of organ culture to microbial contamination can be turned into an advantage because it allows the detection of residual micro-organisms on the cornea before surgery. Both preservation techniques seem to result in similar graft survival. The method of choice for preservation of the donor cornea is dictated by a number of factors mentioned in this review and this helps to explain the geographical differences in the use of the different techniques.     

TFOS DEWS II pain and sensation report

Pain associated with mechanical, chemical, and thermal heat stimulation of the ocular surface is mediated by trigeminal ganglion neurons, while cold thermoreceptors detect wetness and reflexly maintain basal tear production and blinking rate. These neurons project into two regions of the trigeminal brain stem nuclear complex: ViVc, activated by changes in the moisture of the ocular surface and VcC1, mediating sensory-discriminative aspects of ocular pain and reflex blinking. ViVc ocular neurons project to brain regions that control lacrimation and spontaneous blinking and to the sensory thalamus. Secretion of the main lacrimal gland is regulated dominantly by autonomic parasympathetic nerves, reflexly activated by eye surface sensory nerves. These also evoke goblet cell secretion through unidentified efferent fibers. Neural pathways involved in the regulation of meibomian gland secretion or mucin release have not been identified.In dry eye disease, reduced tear secretion leads to inflammation and peripheral nerve damage. Inflammation causes sensitization of polymodal and mechano-nociceptor nerve endings and an abnormal increase in cold thermoreceptor activity, altogether evoking dryness sensations and pain. Long-term inflammation and nerve injury alter gene expression of ion channels and receptors at terminals and cell bodies of trigeminal ganglion and brainstem neurons, changing their excitability, connectivity and impulse firing. Perpetuation of molecular, structural and functional disturbances in ocular sensory pathways ultimately leads to dysestesias and neuropathic pain referred to the eye surface. Pain can be assessed with a variety of questionaires while the status of corneal nerves is evaluated with esthesiometry and with in vivo confocal microscopy.     

角膜保存方法现状及进展

角膜内皮细胞(corneal endothelial cell, CEC) 是保证角膜正常生理功能的基础,角膜移植术后患者的视力恢复与角膜内皮细胞的活性有很大关系,保持供体角膜正常的自净状态和角膜内皮细胞的功能状态具有重要的临床意义.国内外目前有多种经典的角膜保存方法,明显延长了角膜保存的时间,提高了供体角膜的质量.本文将就供体角膜的保存方法的现状及其进展进行综述.