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1.
M M Archuleta J L Born R M Montano S W Burchiel 《Toxicology and applied pharmacology》1992,113(1):133-137
Previous studies have shown that 7,12-dimethylbenz[a]anthracene (DMBA) is cytotoxic to various murine lymphoid tissues, including the spleen, thymus, mesenteric lymph nodes (MLNs), and Peyer's patches (PPs). In the present studies, we measured the amount of covalent binding of [3H]DMBA to lymphoid and nonlymphoid tissues and correlated these findings with the overall levels of [3H]DMBA (and derived substances) present in various tissues following a single oral administration to mice. Results show that [3H]DMBA was taken up relatively rapidly from the GI tract and that it was nearly completely eliminated within 24 hr via the feces. Peak plasma levels were obtained approximately 6 hr after gavage, and most organs (including brain, heart, liver, lung, kidney, spleen, and thymus) achieved their peak level of DMBA at this time. Maximal concentrations of DMBA were detected in gut-associated lymphoid tissues (i.e., PPs and MLNs) at 4 hr, during which time covalent binding of [3H]DMBA was also maximal. The time course for covalent binding was different in the liver, lung, thymus, and spleen, peaking at 6-12 hr. The amount of covalent binding of [3H]DMBA and derived metabolites in the spleen was more than twice that seen in the other tissues examined. Since the spleen has previously been found to be less sensitive to DNA fragmentation induced by DMBA than the PPs, these results suggest that covalent binding may not be the primary determinant of lymphotoxicity in these organs. 相似文献
2.
The authors present 50 cases of cervical spondylotic myelopathy treated by anterior or posterior approach. To assess the severity of the pre- and postoperative neurological symptoms, they define an original ten-point classification scale taking into account gait and urinary disturbance, ability to manipulate objects and pain. With C2-C7 laminectomy, 60% of the patients are improved, essentially for walk. A few cases only (14%) are upgraded for upper limbs function. The authors conclude that this surgical treatment should be applied only when there is a multi-level narrowed canal and predominant lower limbs deficits. The efficacy of the anterior approach depends on complete removal of osteophytes. In cases with complete osteophytectomy, this surgical treatment can improve both the upper and lower limbs function and 77.8% good results are obtained. In a few cases it may be necessary to use both approach successively. Discriminant analysis applied to 12 factors shows that pre-operative scores of upper and lower limbs and sagittal diameter of spinal canal are the most important factors for neurological prognosis. 相似文献
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Almir Moojen Nácul Andrea Prestes Nácul Antônio Greca de Born 《Aesthetic plastic surgery》1998,22(6):444-450
This research presents reports of cases where a biocompatible and alloplastic biomaterial—Bioplastique—was used, associated
with conventional plastic surgery or as a complement to it, with the aim of achieving a better final aesthetic result. Four
cases are presented where Bioplastique was used in association with rhytidoplasty, rhinoplasty, and other surgical techniques.
This material has shown itself to be appropriate to complement surgery; achieving a final result which would not be possible
without any resort to a complement or any other hard procedure by the surgeon and is not more traumatic for the patient. 相似文献
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Public and professional debate over what, if any, action should be taken by state regulatory agencies regarding AIDS and the HIV status of dentists has increased in recent months. To determine if state boards had workable policies in place or were considering such policies, a telephone survey of all state boards was undertaken. All boards participated, although three provided only limited information. As of early 1992, only two boards required evidence of immunity to HVB for relicensure and none require evidence of seronegativity to HIV for relicensure. Twelve percent of the boards anticipate such requirements within two years. None have mandatory HIV testing, but 13 percent anticipate such requirements in the near future. The authors conclude that while few agencies have taken more than tentative steps toward rigorous HIV testing or restrictions, most are aware of much closer public scrutiny. More restrictions seem likely as these agencies attempt to balance public and professional rights and responsibilities. 相似文献
8.
The effect of acute administration of nicotine on the secretory function of the human parotid gland was investigated in 4 male volunteers. After intravenous infusion of 20 micrograms nicotine/kg b.w. within 10 min in all subjects an increased salivary amylase activity and protein concentration was observed. This phenomenon is believed to be caused by a stimulation of parotid beta-adrenoceptors secondary to a nicotine-induced release of catecholamines from the adrenals. 相似文献
9.
Thrombosis of the internal jugular and subclavian vein is often caused by central venous catheters. We report on a 39-year-old patient suffering from clinically suspected thrombosis of the internal jugular and subclavian veins. Thrombosis was confirmed by B-mode-sonography. The development of thrombosis in this case as a consequence of a central venous catheter and of an additional continuous i.v. treatment with human granulocyte/macrophage colony-stimulating factor (GM-CSF) is discussed. 相似文献
10.
Leiomyosarcomas arise rarely in the head and neck. We report a 41-year-old woman with an extremely rare leiomyosarcoma of the floor of the mouth extending to the oropharynx. This article stresses the value of imaging methods such as CT, MRI and ultrasound for preoperative diagnosis, and emphasises histopathological findings. The therapeutic principles and prognostic factors of leiomyosarcomas are illustrated on the basis of this case. 相似文献