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961.
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963.
The origins of delusional beliefs have been a question of great interest for centuries. For many years, the widely held view was that there was a fundamental defect in reasoning in the patient that gave rise to the false belief. Much effort was directed at establishing the kind of defect and the circumstances that triggered it. The search for the basic reasoning defect has met with limited success, mainly because the flaws found in the reasoning of deluded persons are also found with substantial frequency in the general population. The co-occurrence of hallucinations and delusions is consistent with findings that repeated anomalous experiences of various kinds are followed by the development of delusions. In this case, it would be reasonable to regard the hallucinations as exercising a causative role in the development of delusions.  相似文献   
964.
A new carbacephem analog of cefaclor, LY163892, was examined along with four other cephalosporins for chemical stability and for antibacterial activity under a variety of susceptibility test conditions. LY163892 was found to be markedly more stable than cefaclor during storage at 4 and 35 degrees C in human serum, human urine, and various bacteriological media. Under these conditions, LY163892 demonstrated stability equal or superior to the stabilities of cephalexin, cephalothin, and cefuroxime. Broth and agar dilution susceptibility tests did not reveal significant differences in LY163892 activity in a variety of test media, although LY163892 MICs were somewhat higher in Mueller-Hinton chocolate agar or Trypticase soy broth (BBL Microbiology Systems, Cockeysville, Md.) than in other media. The activity of LY163892 against selected pathogens was only slightly influenced by the increased or decreased pH of the test medium, in a manner similar to that of the other cephalosporins tested. Thus, the carbacephem structure of LY163892 appears to represent a more stable cephalosporin than cefaclor, while retaining a similar antimicrobial spectrum.  相似文献   
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967.
Eighty patients with upper extremity vascular trauma were treated during a 4-year period. Of 123 vascular injuries, 95 were arterial, 1 was primary venous, and 27 were associated venous injuries. Causes included penetrating (64%), blunt (27%), and iatrogenic injuries (9%). Arteries injured were ulnar (34), radial (28), brachial (22), subclavian (6), and axillary (5). Numbers of patients with associated injuries were nerve (53), vein (27), bone (23), and soft tissue injuries (60). The most common techniques of arterial repair were end-to-end anastomosis (50), followed by interposition saphenous vein grafting (40). Fasciotomy was used in 36 patients. Two arterial repairs failed during surgery and required revision (1) or thrombectomy (1). One radial artery repair thrombosed during late follow-up, with maintenance of normal extremity perfusion via the ulnar artery. No amputations were required, and 83% of all patients treated for nerve injuries resolved or improved their neurologic deficits. Two or more operations for surgical debridement and subsequent wound closure were required in 35 patients. This study supports an aggressive approach to diagnosis and treatment of complex upper extremity vascular trauma emphasizing meticulous surgical technique, liberal use of fasciotomy, and aggressive intraoperative debridement and repair of associated injuries.  相似文献   
968.
During the past decade, continuous ambulatory peritoneal dialysis has emerged as a successful alternative to hemodialysis in the treatment of chronic renal failure. Performed continuously, peritoneal dialysis achieves total transfer comparable to hemodialysis and removes peptides faster. Studies have shown that survival rates for the two techniques are similar. Peritonitis, the major complication of continuous ambulatory peritoneal dialysis, is decreasing in frequency and can usually be managed at home.  相似文献   
969.
Inherited predisposition to phaeochromocytoma is seen in multiple endocrine neoplasia type 2 syndromes, von Hippel-Lindau (VHL) disease, and neuro-fibromatosis type 1. In addition familial phaeochromocytoma alone has been reported. To investigate the genetic basis for familial phaeochromocytoma alone, we screened three affected kindreds for mutations in the RET proto-oncogene and the VHL tumour suppressor gene. We did not detect MEN 2 associated RET mutations in any family, but missense VHL gene mutations (V155L and R238W) were identified in two kindreds with no clinical evidence of VHL disease. Patients with familial, multiple, or early onset phaeochromocytoma should be investigated for germline VHL and RET gene mutations as the molecular diagnosis of multisystem familial cancer syndromes enables appropriate counselling and screening to be provided.  相似文献   
970.
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