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991.
992.
The craft of surgery has always relied on the use of instruments. Innovations in surgery have paralleled innovations in instrumentation.
Advances in surgical instrumentation continue today and have enabled huge strides in surgical procedures and outcomes during
this generation. Computers and related technology are now changing the interface between the surgeon and the patient, and
are poised to improve patient outcomes by enhancing the surgeon’s skills and training. The application of computer enhanced
telemanipulators, or “robots”, may specifically enhance operations, for example Heller myotomy, that require good visualization
and precise careful dissection of delicate structures. This review covers the pathophysiology of achalasia and its history
of medical and surgical treatment, leading to modern robotic telesurgical approaches. Improvements in outcome from medical
to standard surgical to robotic telesurgical approaches are discussed. Current operative technique for robotic telesurgical
treatment of achalasia is described and the authors conclude with a glimpse of where, in the future, current research endeavors
will lead us in the treatment of achalasia. 相似文献
993.
994.
Neal G Palmer James R Yacyshyn Herbert C Northcott Brian Nebbe Paul W Major 《American journal of orthodontics and dentofacial orthopedics》2005,128(2):163-167
INTRODUCTION: To plan for future acceptance and implementation of computer-related technology, it is necessary to understand orthodontists' current perceptions and attitudes toward emerging technologies. METHODS: An anonymous, self-administered, mail-out survey of Canadian orthodontists was conducted. The response rate was 45.6% (304/667). RESULTS: Most orthodontists indicated that computer technology could improve current practice efficiency and quality of patient care. Only 15% reported that digital models are quite or very useful; 73.6%, 69.1%, 55%, and 37.4% agreed or strongly agreed with using digital and electronic technology to consult with other dental specialists, other orthodontists, general dentists, and the public, respectively. Cost of the technology was reported as a significant or insurmountable obstacle by 54% of the respondents. Interprovincial legislation, unclear consultation remuneration guidelines, and lack of comfort with the technology were not perceived as significant obstacles. Only 36% reported security or privacy issues as a significant or insurmountable obstacle. CONCLUSIONS: Canadian orthodontists seem to view digital and electronic technology as useful and capable of improving their offices' efficiency and production. Although they are sensitive to some potential obstacles, they are willing to overcome these and incorporate the technology into their practices. 相似文献
995.
In vivo Intracellular Recording of Neurons in the Supraoptic Nucleus of the Rat Hypothalamus 总被引:3,自引:0,他引:3
R. E. J. Dyball J-G. Tasker J-P. Wuarin F. E. Dudek 《Journal of neuroendocrinology》1991,3(4):383-386
Intracellular recordings were made from cells in the hypothalamic supraoptic nucleus in the urethane-anaesthetized male rat using the ventral surgical approach. Impalements lasted from 5 min to 1 h and recorded cells had an input resistance of 55 to 170 megohms. Spikes of over 50 mV were recorded from 14 cells which could be antidromically activated by stimulation of the neural stalk. The spikes showed a hyperpolarizing afterpotential and the broadening characteristic of rapidly firing magnocellular neurons, which recovered rapidly (<200 ms). When depolarized, the cells showed evidence of a transient potassium current. Recurrent synaptic coupling between the recorded cell and adjacent cells would be expected to alter the hyperpolarizing afterpotential of an antidromic spike as compared with a spontaneous spike; no perceptible difference in the waveforms of the different types of spike could be detected in 11 spontaneously active cells. Application of just subthreshold stimuli to the neural stalk did not evoke depolarizing or hyperpolarizing potentials. Suprathreshold shocks to the neural stalk, when the antidromic spike was prevented by collision, also had no discernible effect on membrane potential. Thus intracellular recordings from magnocellular neurons in vivo revealed electrophysiological properties similar to those seen in vitro. No evidence for synaptic interconnection between magnocellular neurons was found in male rats. 相似文献
996.
Utility of the dexamethasone suppression test in the diagnosis of poststroke depression. 总被引:1,自引:0,他引:1
S E Grober W A Gordon M J Sliwinski M R Hibbard E G Aletta P L Paddison 《Archives of physical medicine and rehabilitation》1991,72(13):1076-1079
The utility of the dexamethasone suppression test (DST) in the diagnosis of depression was examined in an outpatient sample of 29 stroke patients. Results indicated that the DST's sensitivity was 15%, its specificity was 67%, and its positive predictive value was 48%. These findings suggest that the DST yields no more information than would be gained from random assignment of the diagnosis of depression. Therefore, it is not a useful measure of mood in these patients. 相似文献
997.
Boom F. A. Van der Heijden Van Beek M. A. E. Paalman A. C. A. Stout-Zonneveld A. 《International journal of clinical pharmacy》1991,13(3):130-136
International Journal of Clinical Pharmacy - In order to calculate the minimum sterilization process conditions to obtain the generally accepted sterility level (less than 1·10?6... 相似文献
998.
999.
L Padeletti A Michelucci T Giovannini A Mezzani A Monopoli F Franchi 《Giornale italiano di cardiologia》1989,19(5):411-416
Programmed atrial stimulation at five atrial sites was performed to evaluate electrophysiologic atrial properties in 17 control patients (14 M, 3F, mean age 61 +/- 9 years) (Group A) and in 18 patients with paroxysmal atrial fibrillation (13 M, 5 F, mean age 61 +/- 5 years) (Group B) with normal sinus node function. The mean value of the P wave duration was similar in both groups. Programmed atrial stimulation was performed at five atrial sites: high, medium and low lateral wall, and high and low medial wall. We evaluated the following parameters: A) local conduction delay measured at the functional refractory period as the difference between A1-A2 and S1-S2 intervals; B) widening of local electrogram measured at the functional refractory period as the difference between A1-A2 interval measured at the end of each local electrogram and A1-A2 interval measured at the beginning of each local electrogram. We evaluated the mean and the maximum value of the two above-mentioned parameters; C) dispersion of effective refractory period and functional refractory period, determined as the longest minus the shortest refractory period from the range of refractory periods measured in each patient; D) the mean of effective refractory periods and functional refractory periods observed at five atrial sites. Mean and maximum local conduction delay, mean effective and functional refractory periods did not present significant differences in both groups.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
1000.