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91.
92.
Jack T. Trevors 《Environmental toxicology》1987,2(3):283-291
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
93.
Is neurogenesis reparative after status epilepticus? 总被引:1,自引:0,他引:1
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A multi-institutional study 'Pathobiological Determinants of Atherosclerosis in Youth' (PDAY) was initiated to document the natural history of atherosclerosis, its relationship to risk factors, and pathobiology of lesion development in young subjects. Pathology laboratories in nine centers collected arteries and tissues from over 2000 persons from 15 through 34 years of age whose deaths were attributed to homicides, accidents, or suicides. Arteries were evaluated for lesions, and risk factors were analyzed in a central laboratory. Postmortem risk factors included serum lipoproteins, serum thio-cyanate (smoking), glycohemoglobin (diabetes), thickness of panniculus adiposus (obesity), small renal artery changes (hypertension) and apoprotein isoforms. This study documents the development of atherosclerosis at an early age. It also shows that the recognized risk factors for coronary heart disease are associated with lesion development in the arteries of these young subjects. The PDAY study has a counterpart in Japan where the development of atherosclerosis has been studied in young subjects. This Japanese study, in a population in which coronary heart disease has not yet become a major epidemic, has findings quite similar to the findings from the PDAY study. Studies of atherosclerosis in both Japan and the USA provide strong justification for reducing risk factors in young persons. 相似文献
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97.
Azra Raza Harvey D. Preisler Ya Qin Li Richard A. Larson Jack Goldberg George Browman John Bennett Hans Grunwald Ralph Vogler Cathi Kukla 《American journal of hematology》1993,42(4):359-366
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
98.
Rainer Hofmann Reynaldo Gomez Marshall L. Stoller Emil A. Tanagho Jack W. McAninch 《Urological research》1993,21(5):333-337
Summary Mechanisms for maintaining passive continence in the efferent limb of urinary diversions include compression of tissue, peristalsis, equilibration of pressure and use of valves. Motor activity and pressure in the ileum, ileocecal valve (ICV) and the colon were evaluated in dogs. Spontaneous activity and pressure were compared with stimulated pressure response and activity. Stimulation was performed at the pelvic nerve and the small nerves in the mesenterium, as well as direct neurostimulation of the bowel. Resting pressure at the ICV was 12.7±0.4 cmH2O rising to 26.4±2.2 cmH2O during spontaneous depolarization. Stimulation of the pelvic nerve resulted in increased colonic motor activity with unchanged pressure. Electric stimulation of small mesenterical nerves to the ICV increased pressure in the ICV to 35.0±4.1 cmH2O, while direct myoelectric stimulation of the ICV zone increased the intraluminal pressure to 75.0±3.2 cmH2O. Termination of the electric stimulation was followed by a slow decrease of pressure to the resting level a period of 30–45 s. Maintaining continence at the ICV with long-term constant or intermittent stimulation seems feasible. 相似文献
99.
Jack A. Friedland M.D. William M. Jacobsen M.D. Sarvam TerKonda M.D. 《Aesthetic plastic surgery》1996,20(6):453-462
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
100.