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81.
P. J. Borgstein R. V. Gordijn Q. A. J. Eijsbouts M. A. Cuesta 《Surgical endoscopy》1997,11(9):923-927
Background: The aggressive surgical approach to patients suspected of having acute appendicitis for fear of perforation, and the inaccuracy of available diagnostic methods lead to an unacceptably high negative appendicectomy rate, especially in young women, in whom gynecological disorders frequently mimic appendicitis. Our objectives were to determine the value of diagnostic laparoscopy in women of child-bearing age to reduce the number of negative laparotomies and establish the correct diagnosis to allow prompt and appropriate treatment. Methods: 161 consecutive adult female patients under 50 years of age with a clinical diagnosis of acute appendicitis underwent diagnostic laparoscopy prior to the planned appendicectomy. If an inflamed appendix was found, appendicectomy was usually done through a muscle-splitting McBurney incision. Other diagnoses were treated accordingly. A normal appendix was not removed. Results were compared to a group of 42 similar patients in whom the laparoscopy was omitted for various reasons, to 23 postmenopausal women, and to all 137 male adults, directly operated by the McBurney approach. Results: After laparoscopy, 55% of the patients required appendicectomy for appendicitis while in 23% a gynecological diagnosis was made in spite of previous examination by a gynecologist. Fourteen percent had a negative laparoscopy. There were no false-negative results. The negative appendicectomy rate after laparoscopy was 5% due to two false positives and eight laparoscopy failures. In the group of fertile females who escaped laparoscopy the negative appendicectomy rate was 38%. The respective rates for postmenopausal women and men were 4% and 8%. Conclusions: All women of child-bearing age suspected of having acute appendicitis should undergo diagnostic laparoscopy prior to the planned appendicectomy, regardless of the certainty of the preoperative diagnosis. This is currently the only way to reduce the negative appendicectomy rate and establish a correct diagnosis allowing prompt and appropriate treatment. In male patients and postmenopausal women one may proceed directly to emergency appendicectomy. 相似文献
82.
The distribution of 12 different binding sites for acetylcholine, L-glutamate, GABA, 5-hydroxytryptamine, dopamine and noradrenaline was measured with quantitative receptor autoradiography in four regions of the rat basal forebrain (medial septal nucleus including vertical and horizontal limbs of the diagonal band of Broca, magnocellular preoptic nucleus, substantia innominata and basal nucleus of Meynert, ventral pallidum). L-Glutamate binding sites represent the largest portion of the analysed receptors in all regions, followed by muscarinic2, 5-hydroxytryptamine1 and GABAA receptors. Muscarinic1, dopamine1, dopamine2 and 5-hydroxytryptamine2 receptors and alpha 1-, alpha 1A- and alpha 1B-adrenoceptors represent the minor receptor populations. The largest portion of the dopamine receptors is represented by the dopamine1 subtype, and the alpha 1B subtype dominates the alpha 1-adrenoceptor group. A heterogeneity of the distribution patterns of the different receptors throughout the basal forebrain regions is found. A comparison of the patterns shows that alpha 1-adrenoceptors have a similar regional distribution to that of the muscarinic2 receptors, but both receptor types have reciprocal distributions compared with the 5-hydroxytryptamine1 receptors. The results indicate that one transmitter may exert different effects in the basal forebrain regions depending on the densities of the respective receptor subtypes. Moreover, similar or reciprocal distribution patterns of some, but not all, analysed receptors point to a non-random association (co-distribution) of the different transmitter systems in the basal forebrain regions. 相似文献
83.
ROBERT Q. MARSTON 《Medical education》1994,28(S1):105-107
The Robert Wood Johnson Commission on Medical Education focused on evidence that, in the midst of the genetic revolution in medicine, medical students all too often are not engaged by the science component of their education. Medical education is being driven by social as well as these intellectual forces to make fundamental changes. In the USA, the rich array of scientific talent can be used more effectively, and there is a new significance for the behavioural, social, probabilistic, and information sciences. The Report discusses the general changes under way in the USA and includes examples from the eight schools in the Robert Wood Johnson Foundation's Preparing Physicians for the Future: A Program in Medical Education .
Another report explores the reasons why the general changes under way in North American medical education are difficult to bring about. Educating Medical Students is the report of the Assessing Change in Medical Education: The Road to Implementation (ACME-TRI) project of the Association of American Medical Colleges. This project, funded by the Charles E. Culpeper Foundation, explored the recurring problems in medical students' education that have been reported from the 1930s. The ACME-TRI report documents that most medical schools have not solved these recurring problems, summarizes the schools' views of the barriers to solving these problems, and identifies strategies to assist schools in overcoming or minimizing the barriers they have identified.
Together, the Robert Wood Johnson Commission report and the ACME-TRI report provide a context in which to consider the complex issues facing medical education in the 21st century. 相似文献
Another report explores the reasons why the general changes under way in North American medical education are difficult to bring about. Educating Medical Students is the report of the Assessing Change in Medical Education: The Road to Implementation (ACME-TRI) project of the Association of American Medical Colleges. This project, funded by the Charles E. Culpeper Foundation, explored the recurring problems in medical students' education that have been reported from the 1930s. The ACME-TRI report documents that most medical schools have not solved these recurring problems, summarizes the schools' views of the barriers to solving these problems, and identifies strategies to assist schools in overcoming or minimizing the barriers they have identified.
Together, the Robert Wood Johnson Commission report and the ACME-TRI report provide a context in which to consider the complex issues facing medical education in the 21st century. 相似文献
84.
Tetraethylammonium (TEA) effects on K currents were examined on either side of the membrane of hippocampal CA1 neurons by means of whole-cell voltage-clamp recording and intracellular perfusion. Recording media contained ion channel blockers to allow the selective activation of voltage-dependent K currents which consisted of a rapidly decaying component (A-current) and a delayed component. Voltage protocols were applied to separate the A-current from the delayed component. Results show that 10 mM extracellular TEA suppressed 50 +/- 11% (S.D., n = 4) of the delayed current at different levels of depolarization but had little effect on the A-current. In contrast 10 mM TEA applied by intracellular perfusion suppressed the A-current by 42 +/- 10% (S.D., n = 4) in addition to inhibiting the delayed currently 55 +/- 15% (S.D., n = 4). Both the intracellular and extracellular actions of TEA on K currents showed no voltage- nor time-dependency. The results suggest that voltage-dependent transient current (A-current) is mediated through a separate group of ionic channels distinct from those that sustained the delayed current. Furthermore, the asymmetrical effects of intracellular and extracellular TEA on the transient current are similar to those described for the A-current in molluscan neurons. This observation supports the notion that the structure of the ion channel mediating the A-current is closely conserved across different species. 相似文献
85.
86.
87.
M Hettiarachchi E Q Colquhoun J M Ye S Rattigan M G Clark 《International journal of obesity (2005)》1991,15(1):37-43
d,l-Norephedrine (phenylpropanolamine) which is both a demethylated analogue and a metabolite of d,l-ephedrine, is a reputed anorectic agent. In the present study the proposed most active isomer of this mixture, l-norephedrine has been assessed as a peripherally acting thermogenic agent in the isolated perfused rat hindlimb. l-Norephedrine produced a dose-dependent increase in oxygen uptake and perfusion pressure and increased lactate production. Whereas propranolol potentiated the increase in oxygen uptake and perfusion pressure produced by l-norephedrine, prazosin significantly and nitroprusside totally inhibited both of these changes. Nitroprusside also completely inhibited the increase in lactate production. We conclude that norephedrine has a hitherto unrecognized peripheral thermogenic activity in the perfused rat hindlimb resulting from its interaction with alpha 1 adrenergic receptors that control vasoconstriction in this tissue. 相似文献
88.
Through a critical study of herbalogy, it is concluded that the mature seeds of Alpinia zermubet were used as caodoukou in ancient times. The original plant of Yutao recorded in Zhiwu Mingshi Tukao may be the species of Alpinia katsumadai. Baidukou used in ancient times may be the seeds of Alpinia katsumadai found in the south of China, or Amomum compactum and Am. kravanh imported from foreign countries. 相似文献
89.
H S al-Rimawi A A al-Rashied K C Aboo-Backer Q A al-Saleh M F Jallad S Malik 《Annals of tropical paediatrics》1991,11(3):301-303
We report two successful pregnancies in a 17-year-old Arab girl who had received modern combination chemotherapy and central nervous system minimal disease therapy for childhood acute lymphoblastic leukaemia at the age of 9.5 years. 相似文献
90.
S P Brown E R Anderson Q He S Liu Q Wu H Li R Whittle 《The Journal of sports medicine and physical fitness》1992,32(3):288-292
To compare the oxygen cost of submaximal exercise on the Stairobic stepping (SS) machine with bench stepping (BS), 12 healthy men and women (mean age 23 years) underwent six different five minute exercise bouts that were randomly assigned. Tests were conducted using standard open circuit calorimetry. SS at 40 and 60 st/min was equal to BS at 20 st/min and SS at 80 st/min was equal to BS at 30 st/min for VE and RER. VO2 was equal at 20 st/min (BS) and 60 st/min (SS), and 30 st/min (BS) and 80 st/min (SS). Stairobic MET (SM) displayed values over-estimated actual MET (AM) values at the two lowest SS rates and under-estimated the AM value at the highest SS rate. Forty-eight observations of the MET response of SS were conducted and analyzed (BMDP2R) in a forward stepping solution. The multiple regression equation calculated for AM was: AM = -0.567 + -0.012 (WT) + 0.063 (rate) + 0.612 (SM) with an adjusted R2 of 0.82 and a SEE of 0.90. The physiologic cost of BS was approximately equal to SS at two to three times the BS rate of stepping. 相似文献