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101.
Stephen Girard trader, banker, millionaire, and patriot lived 81 full and exciting years. Apparently born with a blind or amblyopic right eye, he emigrated from Bordeaux. France, via Santa Domingo to the United States, and finally settled in Philadelphia, where he developed a successful maritime trade. Ultimately, Girard became the first multimillionaire in the United States. Extremely generous, he often walked from his home in the center of Philadelphia to his farm in what is now South Philadelphia distributing shoes to needy children. Probably Girard’s most heroic gestures were his gallant fight against the yellow fever epidemic in 1793 and his loan to the U.S. government during the War of 1812, which allowed the bankrupt country to continue the conflict and ultimately to win the war. Presented, in part, at the tenth annual meeting of the David G. Cogan Ophthalmic History Society, the College of Physicians of Philadelphia, March 8 and 9, 1997.  相似文献   
102.
Summary. The first theoretical reflections concerning the relation of hormone production with the ageing process stemmed from Charles Edouard Brown-Sequard (1817–1894). At the age of 72 years he experimented on himself with an injection of animal testicular extract.
The Viennese physiologist Eugen Steinach (1861–1944) gained world-wide acknowledgement for his theory of 'autoplastic' treatment of ageing. He deduced that after vasoligation, an increased incretory hormonal production would ensue following the cessation of the secretory output of the gonads. The first operation was performed in 1918 and resulted in a vasectomy boom over the next two decades.
The Russian Serge Voronoff (1866–1951), working in Paris, was one of the first to transplant testicular tissue from a monkey into a human reproductive gland in 1920. Five years later he had already performed this procedure on 300 patients and attracted patients from all over the world.
In America early efforts of human testicular transplantation were performed by Frank Lydston and V.D. Lespinasse. Steinach's vasoligation was taken over by many American doctors, e.g., Harry Benjamin and Charles H. Chetwood. Among the patients who underwent a rejuvenation operation according to Steinach's method were Sigmund Freud (1856–1939) and the Irish poet and Nobel Prize winner William Butler Yeats (1865–1939). Two caricatures from the German magazine Simplicissimus published in 1927, confirm that the rejuvenation operations were constantly in the limelight of the printed media. From 1935 onwards rejuvenation operations gradually lost their appeal due to the introduction of artificial androgens.  相似文献   
103.
We quantitatively investigated the effect of carbidopa/levodopa (25/100) on physical fatigue during finger tapping and force generation in a double-blind, placebo-controlled crossover study. Parkinson's disease (PD) subjects were randomly assigned to carbidopa/levodopa or placebo for Visit 1 or 2 and participated in the following two studies: (1) Finger tapping. Twenty-five PD patients used their index fingers to strike two keys 20 cm apart on a musical instrument digital interface (MIDI) keyboard. The slopes of the regression line of dwell time and movement time were used to assess the rate of fatigue development. (2) Force generation. Twelve PD patients contracted the wrist extensors maximally to obtain a baseline maximum voluntary contraction (BMVC) force. Then they repetitively contracted the wrist extensors at 50% of the BMVC for 7 seconds and rested for 3 seconds. An interval maximum voluntary contraction (IMVC) was measured every three repetitions. Fatigue was defined as an IMVC of less than 60% of the BMVC. The slope of the regression line of IMVC was used to assess the rate of force decline. These two studies were repeated 1 hour after carbidopa/levodopa (25/100) or placebo. Subjects filled out the Multidimensional Fatigue Inventory (MFI) at the beginning of the first visit. Results showed that the slope of dwell time decreased with levodopa but not with placebo (P = 0.004). The rate of force decline also decreased with levodopa but not with placebo (P = 0.01). The subscores in the dimension of physical fatigue in the MFI did not correlate with the rate changes in dwell time or the rate changes in force decline. We concluded that (1) levodopa improves physical fatigue in finger tapping and force generation, (2) physical fatigue in Parkinson's disease is at least partially related to dopamine deficiency, and (3) the MFI measures different aspects of physical fatigue compared with those measured by finger tapping and force generation.  相似文献   
104.
本文应用“冷沉淀”法制备纤维组织粘合剂。对纤维组织粘合剂中主要成份和含量进行了测定,并测定了主要理化性质,建立了动物实验模型,观察了实验兔对纤维粘合剂的反应。  相似文献   
105.
Summary: Summary. A study was conducted to determine whether the attitudes of medical students to death and caring changed during the 3 months following exposure to cadaver dissection. All first-year students were invited to complete a questionnaire immediately before their initial cadaver dissection experience, after 6 weeks, and after a further 3 months. The questionnaire reflected attitudes to death, violent death, death of someone known to the respondent and caring when someone known to the respondent is seriously injured. Ethnicity and previous exposure to dying has no effect on responses, but overall men students' reactions were significantly less than for women ( P < 0.001). The responses given on the final part of the questionnaire after 3 months were significantly lower than those to most questions in the first part of the questionnaire. The exceptions were those questions where the subject in the given scenario was known to the respondent, where reactions were rated significantly greater ( P < 0.001) in the follow-up questionnaire and can be explained on the basis that they were a personal referent.
Students rapidly develop a coping mechanism which enables them to view cadaver dissection as an occupation quite divorced from living human beings. During these early months of training solicitude decreases for those who die who are unknown to them, but concern for personal referents increases. Educators should be aware of the dramatic change of attitudes among students and the process of professionalization which might influence their caring of future patients.  相似文献   
106.
AStudyonExtension-FlexionDynamicLumbarSpineRadiographsinPatientswithLumbarIntervertebralDiscHerniationAStudyonExtension-Flexi...  相似文献   
107.
This article suggests that the United States educational system needs significant changes. The goal of the article is to present a basic educational philosophy that would facilitate this reform. Specifically, education should be viewed as not only a means to an end that teaches basic skills for employment, but also as a process that enhances social development and self-actualization. Recommendations are offered to achieve this important goal.  相似文献   
108.
Self-directed learning is a natural way for adults to learn. Vocational training for general practice is a preparation for unsupervised clinical work that will be supported, in the main, by continuing medical education. This study uses the Self-Directed Learning Readiness Scale to investigate factors influencing readiness for such learning among a sample of general practice trainees. Three principal factors emerged from analysis: enjoyment and enthusiasm for learning; a positive self-concept as a learner and a factor suggesting the possibility of a 'reproducing' orientation to learning. These factors may reflect approaches to learning in general rather than these adopted for professional learning, but offer helpful pointers for the development of both vocational training and of continuing medical education.  相似文献   
109.
From birth onwards, auditory stimulation directs and intensifies visual orientation behaviour. In deaf children, by definition, auditory perception cannot take place and cannot, therefore, make a contribution to visual orientation to objects approaching from outside the initial field of view. In experiment 1, a difference in catching ability is demonstrated between deaf and hearing children (10-13 years of age) when the ball approached from the periphery or from outside the field of view. No differences in catching ability between the two groups occurred when the ball approached from within the field of view. A second experiment was conducted in order to determine if differences in catching ability between deaf and hearing children could be attributed to execution of slow orientating movements and/or slow reaction time as a result of the auditory loss. The deaf children showed slower reaction times. No differences were found in movement times between deaf and hearing children. Overall, the findings suggest that a lack of auditory stimulation during development can lead to deficiencies in the coordination of actions such as catching which are both spatially and temporally constrained.  相似文献   
110.
All-Union Surgical Research Center, Academy of Medical Sciences of the USSR, Moscow. (Presented by Academician of the Academy of Medical Sciences of the USSR N. N. Malinovskii.) Translated from Byulleten' Éksperimental'noi Biologii i Meditsiny, Vol. 112, No. 12, pp. 653–657, December, 1991.  相似文献   
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