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91.
We developed a thyroid hormone (TH) inducible primary screening assay for the identification and assessment of man-made chemicals that interfere with the TH-signalling pathway within target cells. The assay was developed in a Xenopus laevis cell line that was transduced with a self-inactivating (SIN) lentivirus vector (LV) containing a luciferase gene. The luciferase activation in this cell line was TH-specific: 3,3',5-L-triiodothyronine (T(3)) > 3,3'5-L-triiodothyroacetic acid (Triac) > 3,3',5-D-triiodothyronine (D-T(3)), > L-thyroxine (T(4)) > 3,3',5'-L-triiodothyronine (rT(3)). The application of the ligand-dependent luciferase assay for screening for thyroid system-disrupting chemicals revealed that three phthalates (dicyclohexyl phthalate, n-butylbenzyl phthalate, and di-n-butyl phthalate), two herbicides (ioxynil and pentachlorophenol) and a miticide (dicofol) had 3,3',5-L-triiodothyronine- T(3)- antagonist activity at concentrations ranging from 10(-6) to 10(-5) M. These chemicals also inhibited the expression of the endogenous primary T(3)-response TH nuclear receptor beta (TRbeta) gene. The inhibitory characteristics of these chemicals were similar for both assays performed, although the assay for T(3)-dependent activation of TRbeta gene was more sensitive than the luciferase assay. These results indicate that the luciferase assay was a rapid method with a small intra-assay variation for the primary screening of thyroid system-disrupting chemicals. Of the six chemicals, only n-butylbenzyl phthalate and pentachlorophenol exhibited T(3)-antagonist activity in an in vivo metamorphosis-based assay. It should be noted that chemicals elicited thyroid system-disrupting activity in the luciferase assay did not always interfere with the thyroid system in vivo.  相似文献   
92.
An 18-year-old woman presented with left elbow joint pain. Radiographs and computed tomographic scan showed a well-defined osteolytic lesion of the left ulna associated with a honeycomb appearance on the radiographs. Magnetic resonance images showed intermediate signal intensity on T1-weighted images and mixed intermediate and high signal intensities on T2-weighted images. Only the periphery of the lesion enhanced with intravenously injected gadolinium-diethylenetriamine pentaacetic acid. The lesion was curetted to avoid pathologic fracture, and a histologic diagnosis of cavernous hemangioma of bone was made. Hemangioma involving the ulna is rare, but should be included in the differential diagnosis of a radiographic osteolytic lesion with a honeycomb appearance. Received: 17 September 1999 Revision requested: 31 October 1999 Revision received: 10 December 1999 Accepted: 13 December 1999  相似文献   
93.
BACKGROUND AND AIMS: Bacterial translocation is precipitated by an increase in bacteria or endotoxin, depression of the membrane barrier, and an increase in mucosal permeability. Plaunotol is a mucosal protective agent, and observed to have a strong suppressive effect on superoxide production. In this study, the effect of plaunotol on bacterial translocation was examined using the model of ischemia and reperfusion. METHOD: Male Sprague Dawley rats were used to create the following model for evaluation of bacterial translocation: (i) the control group; (ii) the preventive dose group (plaunotol 30 mg/kg/day one week before surgery); (iii) the therapeutic dose group (plaunotol 30 mg/kg/day one week after surgery); and (iv) the full dose group (plaunotol 30 mg/kg/day one week before surgery and one week after surgery). Bacterial translocation was assessed as the blood concentration of the endotoxin. RESULTS: In the control group, the endotoxin increased significantly 3 days postsurgery (13.7+/-5.6 pg/ml) compared with before surgery (1.1+/-0.1 pg/ml). In the preventive and full-dose groups, the erndotoxin decreased significantly 3 days postsurgery (4.4+/-2.8 pg/ml, 5.7+/-2.7 pg/ml, respectively) compared with that of the control group. CONCLUSION: Plaunotol in the preventive and full-dose groups decreased the endotoxin. This suggests that plaunotol is one of the protectors for bacterial translocation.  相似文献   
94.
We report a case of preeclampsia associated with hemolysis, elevated liver enzymes, and low platelet count (HELLP) syndrome and concomitant nonbiliary acute pancreatitis and cholecystitis in the first postpartum day. A thorough investigation ruled out known etiologies of both pancreatitis and cholecystitis. Following conservative treatment, the patient's HELLP syndrome, pancreatitis, and cholecystitis resolved on the third postpartum day. Preeclampsia is associated with microvascular abnormalities that may involve the splanchnic circulation. These abnormalities may cause not only HELLP syndrome but also pancreatitis and cholecystitis. Recognizing that ischemia can damage not only the liver but also the pancreas and gallbladder, could result in improvements in the diagnosis and management of pancreatitis in patients with preeclampsia.  相似文献   
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The total number of natural teeth was related to swallowing function among older adults; however, limited information is available regarding the impact of occluding pairs of teeth on swallowing function. This study aimed to examine the association between posterior teeth occlusion and dysphagia risk in older nursing home residents. This cross‐sectional study included 238 residents aged ≥60 years from eight nursing homes in Aso City, Japan. Swallowing function was evaluated using the modified water swallowing test (MWST); the primary outcome was dysphagia risk (MWST score ≤3). Posterior teeth occlusion was assessed using number of functional tooth units (FTUs), determined based on number and location of the remaining natural and artificial teeth on implant‐supported, fixed or removable prostheses. Univariate and multivariate logistic regression analyses were performed to examine the association between posterior teeth occlusion and dysphagia risk, adjusted for the covariates of number of natural teeth, demographic characteristics, comorbidities, physical function, body mass index and cognitive function. Of the 238 subjects, 44 (18·5%) were determined to be at risk of dysphagia based on the MWST scores. The odds ratio (OR) of dysphagia risk decreased in subjects with higher total FTUs [OR = 0·92, 95% confidence interval (CI) 0·87–0·98]. After adjusting for covariates, this association remained significant (OR = 0·90, 95% CI 0·84–0·97). Loss of posterior teeth occlusion was independently associated with dysphagia risk in older nursing home residents. Maintaining and restoring posterior teeth occlusion may be an effective measure to prevent dysphagia.  相似文献   
98.
We report a 38‐year‐old male patient who presented with cutaneous lesions mimicking widespread discoid lupus erythematosus with high‐grade fever, arthralgia and lymphadenopathy. Additional lymph node and skin biopsies, however, revealed karyorrhectic debris without neutrophils and numerous CD68‐positive cells, a characteristic finding of Kikuchi's disease (KD). Comparing skin biopsies on different occasions, we could see different forms of histopathology. The histopathology of skin lesions of KD may vary during the clinical course, which may reflect the stage of the disease.  相似文献   
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