Corporate influence on threshold limit values

Investigations into the historical development of specific Threshold Limit Values (TLVs) for many substances have revealed serious shortcomings in the process followed by the American Conference of Governmental Industrial Hygienists. Unpublished corporate communications were important in developing TLVs for 104 substances; for 15 of these, the TLV documentation was based solely on such information. Efforts to obtain written copies of this unpublished material were mostly unsuccessful. Case studies on the TLV Committee's handling of lead and seven carcinogens illustrate various aspects of corporate influence and interaction with the committee. Corporate representatives listed officially as "consultants" since 1970 were given primary responsibility for developing TLVs on proprietary chemicals of the companies that employed them (Dow, DuPont). It is concluded that an ongoing international effort is needed to develop scientifically based guidelines to replace the TLVs in a climate of openness and without manipulation by vested interests.     

绝经后骨质疏松症患者运动干预的最佳证据总结

背景 运动为防治绝经后骨质疏松症经济有效的干预措施之一,但目前其相关证据内容广泛且分散,临床尚无规范、全面的运动指导方案。目的 检索、评价并总结绝经后骨质疏松症患者运动干预的最佳证据。方法 系统检索BMJ Best Practice、Up To Date临床顾问、Dyna Med,英国国家临床医学研究所指南网、国际指南网、苏格兰学院间指南网、美国指南网,加拿大安大略注册护士协会、国际骨质疏松症基金会、英国皇家骨质疏松协会、美国骨质疏松症基金会、澳大利亚皇家全科医师学院、美国妇产科医师学会、加拿大妇产科医师协会、医脉通、澳大利亚乔安娜循证研究所网站,Cochrane Library、CINAHL、Web of Science、PubMed、Embase、中国知网、中国生物医学文献服务系统中关于绝经后骨质疏松症运动干预的临床实践指南、临床决策、证据总结、专家共识、系统评价。检索时限为建库至2022年1月。采用临床指南研究与评价系统(AGREEⅡ)对指南进行质量评价,采用证据总结评价工作表(CASE)对临床决策进行质量评价,采用澳大利亚JBI循证卫生保健中心专家共识的真实性评价工具(2016...     

方剑乔教授针药结合治疗类风湿性关节炎的临床思辨特色与治疗经验

[目的] 介绍方剑乔教授针药结合治疗类风湿性关节炎的临床思辨特色及其临证经验。[方法] 通过整理、回顾、分析方教授治疗类风湿性关节炎的相关文献及医案,从中医病因病机和治则治法等方面,总结归纳方教授治疗类风湿性关节炎的学术经验,并列举医案一则予以佐证。[结果] 临床思辨上,方教授认为“痰、瘀、虚交错”为该病的基本病机,治疗宜针药结合,主要起到同效相须、异效互补和反效制约的作用。临证治疗上,方教授强调,针刺宜整体治疗与局部穴位兼顾,须重视经络辨证。合理应用电针,疼痛急性发作期电针频率多选择“先高后低”,先100 Hz/10～15 min,后2 Hz/30 min;慢性疼痛期电针治疗多选择疏密波(2/100 Hz)。用药强调精准辨证,在该病四种基本证型的基础上提出了阴虚湿热兼证的概念,确立了滋阴清热、通络止痛的治疗大法。倡导适时采用经皮穴位电刺激治疗,其操作简单,携带方便,在镇痛方面具有明显的优势。所举病案采用西药甲氨蝶呤片抑制免疫,稳定病情;中药以祛风除湿为主,佐以藤类药通络行窜、祛风止痛;电针治疗选择频率为2/100 Hz的疏密波调和气血、通络止痛。经治疗后,患者症状缓解,相关指标趋于正常。[结论] 方剑乔教授根据本病的病因病机及临床特点进行辨证论治,针药并重,中西医取长补短,临床特色鲜明,治疗效果显著,值得临床借鉴和推广。     

Changing patterns of binocular visual connections in the intertectal system during development of the frog,Xenopus laevis

Summary In the frog, Xenopus laevis, a system of intertectal connections underlies the visual projection from an eye to its ipsilateral tectal lobe and is involved in the topographic representation of binocular visual space. Rotation of one eye in early life may be followed by a radical rearrangement of the connections in this system. The modified pattern which later emerges is that which keeps the visual projection through the ipsilateral eye in topographic registration with the direct visual projection from the contralateral eye to the same tectal lobe. This plasticity requires visual experience.In this paper we describe the time-course and sequence of events by which this plasticity is effected. Following rotation of one eye in larval animals or in animals undergoing metamorphic climax, the earliest evidence of intertectal modification was found 3–4 weeks after metamorphosis. With increasing intervals after metamorphosis an increasing proportion of animals displayed modified intertectal systems. At intermediate intervals many animals showed partial modifications, which were interpreted as transitional stages in the modification process. Analysis of these transitional stages indicated that the sequence of events involved in the elaboration of a modified intertectal system following the experimental alteration of eye alignment exhibits features in common with rearrangements of the system that occur during normal development in response to growth-related alterations in eye alignment.     

Programming life histories: Effects of maternal and environmental variables upon open-field behavior

Open-field behavior was studied as a function of three classes of variables: maternal characteristics, rearing environment, and sexual experience. Mothers of experimental subjects were either handled or nonhandled in infancy. Subjects were born and reared to weaning either in maternit cages or in Hebb-type free environments and were placed after weaning into either a laboratory cage or free enviroment. Sexual experience consisted either of bearing and raising a litter or no sexual experience. The results confirmed previous findings that offspring of mothers handled in infancy arc significantly less active in the open field than the offspring of nonhandled mothers. The maternal handling variable also interacted significantly with breeding experience: for rats which had not been bred, those raised by nonhandled mothers were more active than those raised by handled mothers; for females with breeding experience the reverse was true. Overall, thosc femalcs which had reared a litter were more active and defecated more than their nonbred littermates.     

Age,experience, and rare-male mating advantages inDrosophila pseudoobscura

Because published experiments documenting frequency-dependent sexual selection have exclusively used young virgins, we endeavored to test for this same phenomenon in females who differed in age and in previous mating experiences. Direct observation tests were conducted employingDrosophila pseudoobscura females of the previously described Arrowhead (AR) and Chiricahua (CH) homokaryotypes. Four-day-old virgin females confer mating advantages on all tested rare males, i.e.,or. AR, and CH. Females who had a previous mating experience when younger award a rare-male advantage only when the rare male is of the same genotype of karyotype as their first mate, and matings are random when the first-mate type males are common. Equivalently aged (11 days) virgin females mate significantly more than expected with minority males if they are of the same karyotype as the females themselves. whereas matings are near random when the males are different. Frequency-dependent mating, therefore, is both age and experience dependent.A. P. is supported by funds from the Biopsychology Program, Hunter College and C.U.N.Y. L.F. is the recipient of USPHS Career Award 2KO3 HD 0903308: work supported by NIH Grant 5RO1 18907-02.Paper presented at the third annual meeting of the Behavior Genetics Association, Chapel Hill, North Carolina, April 7, 1973.     

Effect of early outdoor experience on the activity of wild and semi-domestic deermice

The gross activity of wild and semi-domestic strains of prairie deermice was measured in two kinds of novel test apparatus (tilt-cage and activity wheel). Differences in strain activity were not obtained in either apparatus. Activity was significantly decreased in both strains by early experience in the field and by rearing wild genotype subjects in large laboratory cages. It was suggested that differential early sensory experience associated with both qualitative and quantitative aspects of the early rearing environment may be responsible for the treatment effect. Whereas no daily changes in activity were noted in the tilt-cages, activity in the wheels was sipnificantly higher on day 1 for all groups. In contrast to recent literature, wheel running activity did not change with total water deprivation.     

Employing Empirically Supported Treatments: A Research-Informed Clinical Practitioner Perspective

Ruscio and Holohan (2006 ) offer many excellent ideas for improving research on empirically supported treatments (ESTs) applied to complex cases. They hope that, as more empirical findings are accumulated, clinical practitioners will be more willing to use ESTs in their clinical work with such patients. This commentary suggests additional research strategies that are necessary to acquire information more useful and relevant to clinical practitioners. These include (a) integrating information from research on empirically supported relationship factors with findings from EST outcome research, (b) studying longer term therapies attempting to address issues beyond the symptoms of diagnostic and statistical manual of mental disorders (DSM)-defined disorders, and (c) investigating the efficacy and effectiveness of integrative forms of psychotherapy. The author's successes and difficulties of incorporating ESTs in his integrative therapy for anxiety disorders are highlighted.     

Neonatal social isolation alters both maternal and pup behaviors in rats

The development of emotional behavior is dependent on the early experiences of the infant and the quality of maternal care. In these experiments, the effects of social isolation during the preweaning period on both pup behavior and maternal responsivity were examined. In the first study, the number of ultrasonic vocalizations (USVs) emitted after brief maternal separation was measured in neonatal rats with differing histories of social isolation. The social isolation procedure consisted of 5 days of daily separation from the dam and littermates for either 3 or 6 hr. At both ages tested, socially isolated pups vocalized significantly less than control pups. In the second study, the effects of prior isolation either daily for 5 previous days (Chronic Isolation) or for 4 hr prior to testing (Acute Isolation) were examined in a T-maze choice test. Pup vocalizations in the presence of the dam and dams' maternal behavior were assessed. When the dam was confined to the start box or during the maternal free access period, both Chronic and Acute Isolates vocalized less than pups that had never left the home nest. Dams spent more time with and licked and groomed more frequently and for a longer time both Chronic and Acute Isolates compared to pups that had always been with dams in the home nest. These results suggest that early isolation experience can alter subsequent responses to separation stress in neonatal rats and that maternal behavior is sensitive to the prior experiences of offspring.     

The effects of separation and reunion on the behavior of mother and infant squirrel monkeys

Mother and infant squirrel monkeys that lived together in a socially restricted environment were separated for a period of seven days after the infants had become relatively independent, and were then reunited. Behavioral observations before, during, and after separation indicated that (1) female infants became independent of their mothers earlier than males, (2) neither mothers nor infants were severely affected by separation, and (3) an increase in attachment occurred following reunion only when the mother had a limited history of maternal experience. These results suggest that (1) certain characteristics in the maternal behavior of the squirrel monkey facilitate readjustment in mothers and infants following maternal separation, (2) maternal experience can influence the mother-infant relationship following a period of separation, and (3) the independence of infants from their mothers may be a function of both sex and species.