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Last year Franciscan Children's Hospital & Rehabilitation Center in Boston launched a "Kids' Care-Van" in an attempt to better serve the children of its community. That community, the city's Allston-Brighton neighborhood, is the home of many immigrants and minority group members, people likely to face economic, cultural, and linguistic barriers when seeking healthcare. A survey showed that neighborhood children especially needed better access to the Women, Infants and Children program (WIC), health education, and dental care. The Kids' Care-Van regularly tours Allston-Brighton, making stops at schools, Head Start programs, day care centers, a youth club, and the local YMCA. At those stops children are given medical and dental screenings; if needed, referrals are made to other healthcare sources. Parents, children, and adolescents are also given information about prevention and wellness. To date, 2,500 neighborhood children have been served. Approximately 70 percent have been found to be in urgent need of dental care, a serious problem because many Allston-Brighton parents cannot afford to pay for such care. Few Boston dentists accept Medicaid payment, and there are no other state or federal resources. The van program's manager is currently negotiating with area universities and lobbying local members of the State legislature in hopes of getting some assistance.  相似文献   
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The aim of this retrospective study was to document the various causes of epilepsy determined by computed tomography (CT). We studied 205 CT scans carried out in patients with symptomatic epilepsy. We identified 52 (25.36%) pathological causes: 18 cases (34.62%) of infectious lesions, predominantly toxoplasmosis, 9 cases (17.30%) of tumors, 9 cases (17.30%) of vascular lesions and 8 cases (15.39%) of post-traumatic and atrophic lesions. CT is of great value in the diagnosis of epilepsy, not only in the assessment of the disease, but also for identifying the lesion responsible for the seizures, which may be treatable. It is advisable to carry out a CT scan for any patient presenting with symptomatic epilepsy.  相似文献   
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Summary The relationships of INT2 and ERBB2 amplification and of ERBB2 overexpression in primary breast tumors to prognostic factors, recurrence, and survival have generated considerable controversy. The rationale for this study is that long-term, recurrence-free survival is a more direct criterion for testing the validity of a tumor marker than correlation either with prognostic factors or with short-term recurrence and survival. We examined the association of recurrence with INT2 and ERBB2 amplification and ERBB2 expression by comparing primary breast tumors from patients surviving without recurrence for 8.5 years after diagnosis. the LTS group, to tumors from patients recurring within two years, the RR group. The RR (N = 63) and LTS (N = 61) samples were coded and examined for amplification by Southern blotting and for expression by immunohistochemistry. Comparison between the RR and LTS groups demonstrated that INT2 amplification was associated with a significantly (P = 0.018) higher (5.6-fold) risk of recurrence, an association that remained significant after controlling for lymph node (LN), tumor size (TS), and histograde (HG) status. ERBB2 amplification and expression were not associated with a higher recurrence risk. Survival analyses within the RR group, however, demonstrated significantly shorter survival time among cases with than without ERBB2 amplification (P = 0.018, median survival 16 vs 25 months), or ERBB2 expression (P = 0.019, median survival 15 vs 25 months), but not INT2 amplification. Univariate Cox proportional hazards regression models also demonstrated significantly shorter survival among cases with ERBB2 amplification (P = 0.016) or expression (P = 0.049), that remained significant in multivariate analyses (P = 0.022) for ERBB2 amplification. These results indicate a significant positive association between INT2 amplification and risk for tumor recurrence in the RR as compared to the LTS group. The relationship of ERBB2 amplification or overexpression to patient outcome is more complex. ERBB2 amplification and expression have a significant relationship with shorter survival among patients recurrent within two years, but their occurrence in tumors from women surviving without recurrence for 8.5 years suggests that ERBB2 status is not predictive of shorter survival for all breast cancers.  相似文献   
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Summary 2-deoxycoformycin (2-dCF; Pentostatin), a stoichiometric inhibitor of mammalian adenosine deaminase (ado deaminase), exhibits immunosuppressive and antilymphocytic activity in animal test systems. A clinical pharmacology/phase I study of 2-dCF administered as a single agent has been completed (18 patients). Dose levels ranged from 0.1 mg/kgx1 to 0.25 mg/kg/dayx5; ado deaminase and 2-dCF were measured spectrophotometrically. Plasma decay curves were bi-exponential ( and t1/2 values about 1 and 10 h respectively). Recovery of unchanged 2-dCF from urine (48 h) was 32%–48% of the administered drug. Major toxic manifestations were lymphocytopenia (all patients) and urate nephropathy (1 patient, with subsequent patients in the series receiving allopurinol, 300 mg/day). Three partial responses were seen in seven patients with acute lymphocytic leukaemia receiving 0.25 mg 2-dCF/kg/dayx5.  相似文献   
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Bergamottin (BG) and 6',7'-dihydroxybergamottin (DHB) are the most abundant furanocoumarins present in grapefruit juice and have been proposed as major intestinal CYP3A4 inhibitors contributing to grapefruit juice-drug interactions. The relative contribution of BG versus DHB to the interaction potential is unclear, in part due to inconsistencies in the literature regarding inhibitory potency. To resolve these inconsistencies, the inhibitory kinetics of each furanocoumarin toward CYP3A4 catalytic activity were systematically characterized using representative probes from two distinct CYP3A4 substrate subgroups (testosterone and midazolam). With human intestinal microsomes, DHB was a substrate-independent reversible (Ki, approximately 0.8 microM) and mechanism-based (KI, approximately 3 microM; kinact, 0.3-0.4 min(-1)) inhibitor of CYP3A4. In contrast, BG was a substrate-dependent reversible inhibitor, with a Ki (13 microM) using midazolam that was 8-fold greater than that using testosterone, but a substrate-independent mechanism-based inhibitor (KI, approximately 25 microM; kinact, approximately 0.35 min(-1)). Similar trends resulted with cDNA-expressed CYP3A4, only the KI values for BG were approximately 10-fold lower than with microsomes. This seemed to reflect a much greater degree of microsomal protein binding by BG compared with DHB. Differential inhibition kinetics and binding properties between BG and DHB could account in part for the apparent in vitro inconsistencies in the literature. Results also emphasize the importance of appropriate substrate selection when designing inhibition studies involving dietary constituents.  相似文献   
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These studies were performed to characterize the contribution of the uridine diphosphate glucuronosyltransferase (UGT) enzymes to the clearance of 3'-azido-3'-deoxythymidine (AZT) in vivo and to assess the regulation of UGT activity [including the disposition of the cofactor uridine diphosphate glucuronic acid (UDPGA)] in the placenta. Transport of AZT and the cofactor UDPGA across the human placenta and the glucuronidation capacity of the placenta for AZT were assessed using a human placental cell line (JEG-3), primary cultures of villous term placenta, placental subcellular fractions, and a recirculating perfusion model. Glucuronidation of AZT was consistently observed at approximately 2% of the dose administered. High levels of AZT in cultured primary placental cells and lines caused autoinhibition of AZT metabolism. AZT crossed the perfused placenta in a bidirectional fashion and was at equilibrium after 3 h, whereas the AZT-glucuronide metabolite was excreted preferentially into the maternal compartment. In contrast, UDPGA (10 microM) was rapidly transferred from the maternal to the fetal circulation, being complete after 4 h of perfusion. AZT is transported and glucuronidated by the human placenta, but that placental metabolism of the drug is not significant for whole-body clearance. Likewise therapeutic failure of AZT (5-15%) is not due to placental obstruction of drug passage. Finally, the activity of the UGT enzymes in the placenta is not rate-limited by the supply of UDPGA cofactor, whereas the preferential transport of UDPGA toward the fetus observed here may indicate a role in fetal development.  相似文献   
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