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991.
Endogenous opioids are present in neurons of the vagus and the intrinsic nervous system and they are colocalized with gastrin in antral G-cells. This raises the possibility that endogenous opioids modulate gastrin release. Stimulation of both cervical vagi (10V, 5Hz, 5ms) elicited an increase of arterial plasma gastrin levels at intragastric pH7 or pH2. The response at pH2 was 30% of that at luminal pH7. Atropine reduced vagally stimulated gastrin levels substantially. At luminal pH2 the small residual noncholinergic response was mediated neither by adrenergic mechanisms nor by endogenous opioids. At luminal pH 7 adrenergic blockade with phentolamine and propranolol reduced vagally stimulated gastrin by 60%. In the presence of atropine adrenergic blockade elicited only a small inhibitory effect suggesting that vagal activation of adrenergic mechanisms depends on atropine-sensitive cholinergic pathways. Blockade of opiate receptors by naloxone had no effect on vagal gastrin release, however, the noncholinergic gastrin response was reduced significantly by naloxone, suggesting that cholinergic mechanisms normally restrain activation of endogenous opioids during vagal stimulation. Naloxone had no effect on the noncholinergic, nonadrenergic stimulation of gastrin levels. These data suggest that endogenous opioids can contribute to vagal gastrin release provided the cholinergic restraint is blocked and adrenergic mechanisms stimulate endogenous opioids. In conclusion a major role of endogenous opioids in the regulation of vagal gastrin release can not be detected.  相似文献   
992.
993.
Abstract A high frequency of serum complement component C4A deficiency may explain the higher prevalence and greater severity of systemic lupus erythematosus reported in Australian Aborigines. Inherited deficiencies of serum complement components C4A, C4B, and C2 were examined in two Australian Aboriginal populations from Darwin and Alice Springs and compared with the prevalence of complement deficiencies in white Australian blood donors. The frequency of C4A deficiency alleles was 29% in Darwin Aborigines compared with 12% in Alice Springs and 17% in Canberra blood donors. Partial C4B deficiency was also higher in Darwin Aborigines than in the other populations. Inherited deficiency of serum complement component C2 was not observed.  相似文献   
994.
Authors with wide experience report that the Shouldice technique for repair of inguinal hernia is very effective. The technique has not gained widespread acceptance or notoriety. For example, the 13th edition of Textbook of Surgery, edited by Sabiston, devotes only one paragraph to this type of herniorrhaphy. Because of the excellent results reported by the Shouldice Clinic, this technique was adopted at the Augusta Veterans Administration Hospital, a teaching hospital of the Medical College of Georgia. Since 1976, a total of 604 Shouldice repairs have been performed by supervised house staff; 468 patients have been followed for up to 8 years and a recurrence rate of 1.3 per cent is reported. Although the follow-up is brief, the Shouldice hernia repair is widely applicable and good results are not dependent on wide experience alone.  相似文献   
995.
996.
997.
Summary A group of thirty children with nasal fractures was evaluated retrospectively by means of a questionnaire and hospital records. Age at the time of injury ranged from age 3 to 12 (mean = 8.6) years and mean follow-up period was 9 years. Eight patients reported some degree of nasal obstruction post reduction, but only one patient required submucous resection and two patients underwent septorhinoplasty for appearance. No patients reported class III malocclusion, or required orthodontic treatment or maxillofacial corrective surgery for maxillary hypoplasia. We concluded that a childhood nasal fracture treated by closed reduction does not have deleterious effects on facial or nasal growth.This work was supported in part by the Brigham Surgical Group Foundation, Inc., Boston, Massachusetts, USA  相似文献   
998.
Summary A new modification of microvenous anastomosis, which has increased patency rates while simultaneously decreasing the difficulty of the procedure, is presented in this paper. The primary purpose of this study was to compare the classical and the temporary stent techniques of microvenous anastomosis. Because of problems such as mixing and tangling of strings during insertion and tying of the last four sutures while applying the temporary stent technique, we decided to modify the procedure. The silastic tube was removed through an incision (venotomy), distant from the actual suture line. This modified technique and the other above mentioned techniques were carried out on rat femoral veins. The results indicate that this modification has increased patency rates, shortened the time of anastomosis and facilitated the procedure.  相似文献   
999.
W C Hsiao  P Braun  E R Becker  S R Thomas 《JAMA》1987,258(6):799-802
This article describes the design and methods of a study currently under way to develop a Resource-Based Relative Value Scale (RBRVS); an alternative basis for establishing the payment rate for the services and procedures (S/Ps) of physicians in medical and surgical specialties. Physician resource inputs to be measured include (1) S/P time, (2) pre-S/P and post-S/P times, (3) intensity, (4) practice costs, including malpractice premiums, and (5) the cost of specialty training. These five factors will be combined to produce an RBRVS denominated in nonmonetary units. In the initial phase of the study, data on time and intensity will be obtained through a national survey of physicians who perform these S/Ps. In the second, consensus phase of the project, the investigators will convene a panel of representatives of the medical profession, third-party payers, consumers, and other interested parties to examine areas of agreement and disagreement as to how an RBRVS should be used for policy purposes. The final results of this study are expected by the summer of 1988.  相似文献   
1000.
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