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This paper details the indications, operative technique and results of perineal proctectomy in the management of complete rectal prolapse in a high risk, elderly and debilitated group of patients. Eighteen procedures were performed by one surgeon (A.L.P.) on 16 consecutive patients over a 5 year period. Data collection was via: (i) retrospective analysis of hospital and office records; and (ii) response to a postal questionnaire by the patient, a relative or attending nursing staff. There were 14 females and two males with a mean age of 81 years. All patients had significant associated medical conditions. The interval from the time of a surgical procedure until review varied from 3 to 37 months with a mean follow-up period of 16 months. Total hospital stay varied between 6 and 20 days with a mean of 7 days. Eleven procedures were performed under general anaesthesia and seven under spinal anaesthesia. There was no postoperative mortality. One patient suffered an anastomotic haemorrhage that required operative intervention and another patient suffered a rectal stricture that necessitated dilatation. Two patients were re-operated for recurrent symptomatic prolapse at 34 and 36 months after the initial procedure. Continence improved in seven patients, worsened in one and was unchanged in the remaining patients. Fifteen of 16 patients were considered to have had a successful result from the operation with satisfactory control of the symptom of rectal prolapse. Perineal proctectomy is a low risk operative procedure for the elderly and debilitated group of patients in controlling complete rectal prolapse. If the condition recurs, the procedure can be repeated with equally low morbidity.  相似文献   
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Helms  CA; Kaban  LB; McNeill  C; Dodson  T 《Radiology》1989,172(3):817-820
Magnetic resonance (MR) imaging has been used in the temporomandibular joint (TMJ) primarily to define the disk position. This report examines altered morphology and signal intensity characteristics of the TMJ disk as they relate to the severity of internal derangement. Two hundred sixteen joints in 133 patients with a history of such derangement. were imaged with MR. Disk position, signal intensity, morphology, and the presence of osteoarthritis were determined for each joint. The normal disk was not anteriorly displaced and had a normal "bow-tie" shape. A grade 1 disk was anteriorly displaced and had a normal shape; a grade 2 disk was anteriorly displaced and had an abnormal shape. Forty (19%) joints were considered normal; none of these exhibited osteoarthritis. One hundred thirty-nine (64%) joints were grade 1; osteoarthritis was found in 17%. Thirty-seven (17%) were grade 2; osteoarthritis was found in 95%. All forty normal joints had high or intermediate signal intensity in the disk. Osteoarthritic joints had a higher percentage of disks with diminished intensity (P less than .0001). Severe or untreated osteoarthritis is known to be a complication of TMJ internal derangements; hence this grading system seems to correlate with the severity of internal derangement.  相似文献   
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Demonstration of a capsule plasmid in Bacillus anthracis   总被引:30,自引:16,他引:30       下载免费PDF全文
Virulent and certain avirulent strains of Bacillus anthracis harbor a plasmid, designated pXO2, which is involved in the synthesis of capsules. Two classes of rough, noncapsulated (Cap-) variants were isolated from the capsule-producing (Cap+) Pasteur vaccine strains ATCC 6602 and ATCC 4229. One class was cured of pXO2, and the other class still carried it. Reversion to Cap+ was demonstrable only in rough variants which had retained pXO2. Proof that pXO2 is involved in capsule synthesis came from experiments in which the plasmid was transferred by CP-51-mediated transduction and by a mating system in which plasmid transfer is mediated by a Bacillus thuringiensis fertility plasmid, pXO12. Cells of Bacillus cereus and a previously noncapsulated (pXO2-) strain of B. anthracis produced capsules after the acquisition of pXO2.  相似文献   
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