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31.
The identification of factors associated with breast recurrence following conservative surgery (CS) and radiation therapy (RT) is of potential use in refining patient selection criteria and treatment technique. In an attempt to define such factors we examined the relationship between various clinical, pathologic and treatment characteristics and the likelihood of breast recurrence in 783 patients with clinical stage I or II breast cancer treated between July 1968 and December 1982. Treatment consisted of complete gross excision of the primary tumor and RT to a total dose of at least 60 Gy to the primary site. During this period, pre-treatment mammograms and detailed histologic assessment of the margins of resection were not routinely performed. Median follow-up for surviving patients was 80 months. Thirteen patients (1.6%) were lost to follow-up. Ninety-one patients (12%) have developed a breast recurrence, corresponding to 5- and 10-year actuarial rates of 10 and 18%, respectively. The major feature associated with breast recurrence was the presence of an "extensive intraductal component" (EIC+). An EIC+ tumor was seen in 28% of evaluable cases with infiltrating ductal carcinoma and accounted for 60% of breast recurrences. Forty-three of 166 patients (26%) with EIC+ tumors developed a breast recurrence compared with 29 of 418 patients (7%) without an EIC (EIC-) (p = 0.0001). The 5-year actuarial rates of breast relapse were 24 and 6%, respectively (p = 0.0001). Very young age (defined as 34 years of age or younger) was also a significant factor associated with the risk of breast recurrence. Very young patients comprised 8% of the patient population and accounted for 16% of breast recurrences. Fifteen of 61 very young patients (25%) developed a breast recurrence compared with 76 of 722 older patients (11%) (p = 0.001). The corresponding 5-year actuarial rates of breast recurrence were 21 and 9% (p = 0.005). None of the other clinical or pathological factors examined by univariate analysis were significantly correlated with recurrence in the breast. A multivariate model of site of first failure (polychotomous logistic regression) also showed that EIC+ tumors and very young age were the main factors associated with a high relative risk of breast recurrence. We conclude that EIC+ tumors and very young age are associated with a high risk of breast recurrence for patients treated with limited excision prior to RT.  相似文献   
32.
Neurofibrillary tangles are described in Guamanian and post-encephalitic forms of motor neuron discase (MND) but not in sporadic MND. We report the neuropathological findings in a 79-year-old man who died after a 1-year history of MND without extrapyramidal features or dementia. There was no family history of neurological disease and he had not visited Guam. The spinal cord showed loss of anterior horn cells, and skeletal muscle typical changes of denervation. The brain appeared macroscopically normal but histology revealed many neurofibrillary tangles, particularly in medial temporal lobe structures, insula, nucleus basalis, hippocampus, oculomotor nucleus, raphe nuclei and locus ceruleus. Neurofibrillary tangles were not seen in the primary motor cortex, which appeared histologically unremarkable. Occasional tangles were present in the substantia nigra and pontine nuclei. None were seen in the cerebellum, medulla or spinal cord. The tangles were argyrophilic, and, in sections stained with thioflavin-S, both the intracellular and the extracellular tangles fluoresced strongly under ultraviolet light. The intracellular neurofibrillary tangles reacted strongly with an antibody to tau protein, and only occasional tangles showed weak ubiquitin immunoreactivity. Scattered neuropil threads were present in the cortex in the areas of neurofibrillary tangle formation. No plaques were present in any part of the brain and no A4/ protein immunoreactivity was detected. Ultrastructural examination revealed Alzheimer-type neurofibrillary tangles composed of paired helical filaments. The present findings further extend the spectrum of diverse neurological disorders associated with neurofibrillary tangles.  相似文献   
33.
F O Risinger  M M Brown  R A Oakes  J A Love 《Alcohol》1999,18(2-3):139-145
Dopaminergic systems are thought to play an important role in the motivational effects of ethanol. The present experiments examined the effects of haloperidol (a D2 antagonist) and SCH-23390 (a D1 antagonist) on the acquisition of ethanol-induced conditioned taste aversion. In four separate experiments, adult male Swiss-Webster mice were acclimated to a 2-h/day water restriction regimen. Subsequently they received four conditioning trials consisting of 1-h access to either 0.2 M NaCl (experiments 1-3) or 0.15 % w/v saccharin (experiment 4). After flavor access on trials 1-3, subjects received either haloperidol (0.1, 0.15, or 0.3 mg/kg), SCH-23390 (0.05 mg/kg), or saline followed 30 min later by 0, 2, or 4 g/kg ethanol. Ethanol-flavor pairings reduced subsequent flavor intakes, indicating the development of conditioned taste aversion. Neither haloperidol of SCH-23390 reduced flavor intakes in the absence of ethanol. However, both haloperidol and SCH-23390 reduced ethanol-conditioned aversion depending on ethanol dose and conditioned flavor. These results are consistent with the notion that dopaminergic processes are important for the development of ethanol-induced conditioned taste aversion, and the notion that dopaminergic receptor systems influence both positive and negative motivational effects of ethanol.  相似文献   
34.
We have used different mouse strains to examine in vivo andin vitro responses to the 18 kDa protein of Mycobacterium leprae,which appears to be strongly immunogenic in both mice and humans.B and T cell stimulatory epitopes recognised by different strainsof mice have been mapped using overlapping peptides that spanthe entire 18 kDa protein. Previous work established that Immunizationof mice with the 18 kDa protein results in specific antibodyproduction to common B cell epitopes and immunization of micewith peptides containing these B cell epitopes resulted in theinduction of specific IgG to only a limited subset of epitopesin each strain. Now we report that T cells purified from miceimmunized with peptides that stimulate antibody production,proliferate in vitro when rechallenged. The proliferating Tcells produce levels of IL-2 and IFN-, that indicate antigen-specificT helper type 1 cells are present in significant numbers. Thus,a comparison of in vivo and in vitro data suggests that T cellsbearing the phenotype associated with potentially protectivecell-mediated responses can be primed in vivo by epitopes onsmall peptides. Since T cells from both strains of mice arecapable of responding to the immunogenic synthetic peptidesin vitro, but give different responses to the same peptidesin vivo, factors other than epltope structure appear to influenceT cell subset activation. This may have important implicationsfor diseases such as leprosy where a polarized T cell responseappears to develop and for the development of synthetic subunitvaccines.  相似文献   
35.
36.
Nurses providing care for individuals with eating disorders should identify and test the effectiveness of various milieu factors and nursing therapeutics employed in the treatment of these often-debilitating disorders. Nurses offer presence, role modeling, surveillance, and emotional and physiologic support while guiding reluctant patients to explore and experiment with new behaviors. Nurses provide flexibility, empathy, and rational limit setting in response to the unique and shifting needs of each patient. This interpersonal dynamic is often extremely different from that experienced in the patient's family of origin and, thus, contributes to the essential "interpersonal conditions" that are necessary for the patient to engage meaningfully in treatment. The prevalence of eating disorders suggests that nurses are likely to encounter people with eating disorders in many settings. Nurses should be skilled at spotting disordered eating among an array of clinical presentations (e.g., amenorrhea, disturbed family relationships, athletic injuries) because people engaged in disordered eating are hesitant to volunteer such information. In addition to the shame associated with disordered eating is the stigma associated with psychiatric treatment. Seeking help from a nurse may be perceived as less stigmatizing than seeking care from a psychiatrist. Thus, nurses may serve as important points of entry for the hesitant patient. The initial contact is so essential in setting the stage for the continuation and denouement of therapy. Finally, nurses and patients with disordered eating share at least one commonality. Both groups are predominantly women. The prevailing culture has been implicated repeatedly as a major factor in contributing to the prevalence of disordered eating. Nurses experience the influences of paternalism in their professional practice and confront daily the pressures of socially constructed feminine ideals. These gender-sensitive ways of knowing, which nurses bring to the treatment relationship, should be further analyzed as substantive dimensions with treatment and preventive potential.  相似文献   
37.
Bcl-2, a cell death suppressor protein, is expressed during brain development but is largely down-regulated in the adult central nervous system. We previously reported strong expression of bcl-2 in small, "oligodendrocyte-like" cells (OLC) found in glioneuronal hamartias. These hamartias are microscopic cell rests found in temporal lobe resections from patients with intractable epilepsy and are considered a form of cerebral microdysgenesis. However, a causative relationship between these rests and seizures is not clear. We now report the identification, lineage characterization, and postnatal ontogeny of hamartia-like cell rests in temporal lobes of nonepileptic humans. Postmortem temporal lobes from 28 patients without history of neurologic disease (mean age = 53 years; range = 20 to 83 years) were studied. Microscopic cellular aggregates containing immature-appearing, bcl-2-immunoreactive cells (BIC) (identical to OLC) were observed in 23 of 28 (82%) temporal lobes from nonepileptic individuals. BIC were strongly immunoreactive for neuronal-specific class III beta tubulin, neuronal nuclear antigen, and MAP-2, but were consistently negative for neurofilament proteins and Ki67. Such cells were localized to subventricular regions of the caudal amygdala and often extended into the adjacent subcortical white matter and periamygdaloid cortex. BIC became less abundant with advancing age. These findings suggest that hamartia-like rests containing immature postmitotic neurons are normally present in the human brain and that glioneuronal hamartias may not always represent a maldevelopmental lesion associated with epilepsy.  相似文献   
38.
OBJECTIVE: Because the survival rate has increased for extremely low birth weight neonates, many have raised the concern that the rate of developmental disability among survivors will also increase. To address this concern, we analyzed changes over time in survival and major neurosensory impairment in a sample of extremely low birth weight infants born between July 1, 1979, and June 30, 1994. METHODS: The study sample included 513 infants with birth weights of 501 to 800 g who were cared for in either of the two neonatal intensive care units that serve a 17-county region in northwest North Carolina and who were born to mothers residing in that region. At 1 year of age (corrected for gestation), survivors were examined by a pediatrician and were tested using the Bayley Scales of Infant Development. Major neurosensory impairment was defined as cerebral palsy, a Bayley Mental Developmental Index <68, or blindness. A total of 209/216 (97%) of survivors were examined at 1 year of age. Epoch of birth was defined as follows: epoch 1, July 1, 1979 to June 30, 1984; epoch 2, July 1, 1984 to June 30, 1989; and epoch 3, July 1, 1989 to June 30, 1994. RESULTS: Survival rates for epochs 1, 2, and 3 were, respectively, 24/120 (20%), 63/175 (36%), and 129/218 (59%). In contrast, the proportions with a major neurosensory impairment did not increase over time; rates for successive epochs were 6/24 (25%), 17/61 (28%), and 26/124 (21%). Rates of cerebral palsy were 3/24 (13%), 12/61 (20%), and 9/124 (7%); rates of delayed mental development were 4/24 (17%), 12/61 (20%), and 17/124 (14%); and rates of blindness were 2/24 (8%), 0/62, and 5/124 (4%), respectively. CONCLUSIONS: This analysis suggests that the increasing survival of extremely low birth weight neonates since the late 1970s has not resulted in an increased rate of major developmental problems identifiable at 1 year of age.  相似文献   
39.
Three patients with patent ductus arteriosus and moderate aortic stenosis had a marked reduction in aortic valve gradient following transcatheter ductal occlusion. The hemodynamic effects of an aortopulmonary shunt on the severity of left ventricular outflow obstruction and the implications on intervention are discussed.  相似文献   
40.
McKeown-Eyssen (Cancer Epidemiol. Biomarkers Prevent., 3, 687-695, 1994) and Giovannucci (Cancer Causes Control, 6, 164-179, 1995), noting the striking similarity in lifestyle risk factors for colorectal cancer and insulin resistance, proposed that the hyperinsulinemia, glycemia and hypertriglyceridemia associated with insulin resistance promotes colon cancer. To compare the effect of diet on colon cancer promotion and insulin resistance in the F344 rat, we assessed the effect of fat, n-3 fatty acids and energy in pairwise comparisons on average size of aberrant crypt foci (ACF) and on glucose intolerance in the same animals in a single experiment. Diets high in fat and energy increased and diets with increased n-3 fatty acids and calorie restriction decreased both ACF growth and glucose intolerance compared with control diets. The measures of promotion of colon cancer and insulin resistance were strongly correlated (n = 98, r = 0.67, P < 0.001). In addition, both were highly correlated with daily energy intake (r = 0.62 and 0.66) and were also correlated with basal (post-prandial) insulin, glucose and triglycerides (r = 0.31-0.53, P < 0.01). We concluded that ACF growth and glucose intolerance are correlated for a wide range of diets and that increased circulating energy (glucose and triglycerides) may lead to both colon cancer promotion and insulin resistance.   相似文献   
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