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61.
Samples taken from an activated sludge reactor used for the biodegradation of metal cutting fluids were studied for the presence of plasmid-containing bacteria. Twenty different bacterial isolates contained one or more plasmids. After numerous transfers of the isolates through LB broth, 55% of the plasmids were spontaneously lost as evidenced by agarose gel electrophoresis. Eighty percent of the isolates were resistant to one or more antibiotics, 65% resistant to two or more antibiotics, 40% resistant to three or more, 20% resistant to four or more and 5% resistant to five antibiotics. The isolates were also tested for their sensitivity to several common metals. This study has demonstrated that activated sludge is a natural reservoir for plasmid-containing bacteria involved in biodegradation of wastes.  相似文献   
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A pilot study was conducted of the biological characteristics of the leukemia cells of newly diagnosed patients with poor prognosis acute myelogenous leukemia (AML). This study included measurements of the pretherapy proliferative rate of the leukemia cells in vivo, assessment of differentiation in vivo during remission induction therapy, and the level of expression of the fms, myc, and IL1β genes in pretherapy leukemia cells. Short cell cycle times were characteristic of the best prognostic category and were associated with a rapid reduction in marrow leukemia cells in cytosine arabinoside (araC)-sensitive patients. Expression of c-fms was associated with rapid reduction in marrow leukemia cells during araC therapy and with a successful treatment outcome. Expression of the IL1β gene was associated with short remissions. These studies suggest that when compared to newly diagnosed standard prognosis AML, the leukemia of poor prognosis patients is more likely to exhibit long cell cycle times, low levels of fms expression, and is less likely to be associated with myeloid differentiation during remission induction therapy. © 1993 Wiley-Liss, Inc.  相似文献   
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Surgical rejuvenation of the upper face involves the correction of excess and lax forehead, eyelid, and periorbital skin. Improving the appearance by correcting the effects of aging involves a combination of blepharoplasty and open coronal foreheadplasty. Many surgeons and several reports question the safety of both procedures being performed concomitantly. The difficulty arises in precisely balancing the skin excision from the frontal forehead and upper eyelid areas. Over-resection of skin may result in incomplete closure of the eyelid and dry-eye syndrome, while an inadequate resection may produce a poor aesthetic result. There is no large series that documents the safety and effectiveness of these two procedures being performed concomitantly. Furthermore, with the recent and rapid development of complex multiplanar endoscopic facial rejuvenation techniques, the basic open forehead-plasty has become increasingly overlooked as a legitimate, efficacious technique for rejuvenation of the upper face. The technique utilized in this series is presented in detail. The consistently excellent results obtained satisfy the aesthetic goals of patients as well as the goals of surgeons, and suggest a renewed interest in the technique based upon its simplicity and easily reproducible results.  相似文献   
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The papers which follow are revised and expanded versions of presentations made at the Conference on Improving Florida's Services for the Mentally Ill: The Role of Psychiatry, held in Tallahassee, Florida on October 7–8, 1986, and organized by the Florida Mental Health Institute, University of South Florida. The conference was sponsored by the Florida Department of Health and Rehabilitative Services through the Committee on Public Psychiatry. The authors and their organizational affiliations are listed below  相似文献   
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Two hundred HIV-positive subjects were surveyed to determine their periodontal health status. Particular attention was given to the occurrence of a severe and rapidly progressing form of periodontal disease designated "HIV-associated periodontitis", which has been reported as being unique to AIDS patients. Among the subjects comprising the cohort, 85 subjects had good gingival health, 59 subjects exhibited gingivitis, 49 cases of adult periodontitis were observed, 5 subjects presented with advance adult periodontitis, and 2 cases of necrotizing ulcerative periodontitis (NUP) were found within the group. The periodontitis of the patients in this survey did not have unique or pathognomonic characteristics which could set their periodontal disease apart from the periodontal disease seen in HIV negative population.  相似文献   
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