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The impact of sexual harassment on girls' and women's developing concept of their body and self has rarely been examined with the goal of expanding our understanding of weight and shape preoccupation. In this paper we examine how this pervasive form of violence contributes to young women's uneasiness about their developing bodies and results in a disruption of healthy female development that often gets played out in disordered patterns of eating and intense body monitoring.  相似文献   
23.
Retinoblastoma. The relationship of proliferating cells to blood vessels   总被引:1,自引:0,他引:1  
In 150 retinoblastomas the authors found a uniform thickness of the cuff of viable retinoblastoma cells that surrounds blood vessels. The mean thickness was 98.7 microns with a standard deviation of 11.9 microns. The cross-sectional area of the cuff was negatively correlated with the mitotic activity in the cuff and positively correlated with the diameter of the central vessel. The mitotic activity in the cuff of cells was inversely related to the distance from the central blood vessel. When the cuff was divided into three concentric rings, the inner ring contained a mean of 6.2 mitotic figures, the middle ring contained a mean of 2.9 mitotic figures, and the outer ring contained a mean of 0.6 mitotic figures. This pattern of growth is similar to that observed in other rapidly growing neoplasms in humans and experimental animals. In these tumors this pattern results from reduction in oxygen tension with increased distance from the central blood vessel.  相似文献   
24.
An analysis of hospital discharge data showed that Brampton children 4 years and under had higher rates of hospital admissions for asthma, bronchitis and upper respiratory infections than children in the same age group living in Mississauga and other Ontario municipalities. The present study was done to compare the prevalence and treatment of wheezing and coughing between Brampton and Mississauga children 4 and 5 years of age. The study showed that increased use of pediatricians on the part of Mississauga children in comparison to Brampton children resulted in a higher proportion being placed on anti-asthmatic medications even though the underlying prevalence rate of wheezing and coughing was the same in the two samples. Further study is required to determine whether differences in primary care between the two samples can explain a two-fold increase in hospital admission rates for lower respiratory illness among Brampton preschool children in comparison to their counterparts in Mississauga.  相似文献   
25.
LY354740 is a potent mGlu2/3 agonist with a limited oral bioavailability. Its alanyl prodrug, LY544344, showed high affinity to the intestinal peptide transporter PEPT1, and improved the oral bioavailability of LY354740 in various animal models. The aim of the present study was to investigate the mechanism of in vivo absorption of the dipeptidic prodrug LY544344. The permeabilities of LY544344 and LY354740 were examined in the rat in situ single‐pass intestinal perfusion model. The intestinal absorptive flux of LY354740 was shown to be very low in comparison with LY544344. The absorptive flux of LY544344 could best be described by a Michaelis–Menten process in parallel with a linear process. The estimated parameters were: Jmax = 26.7 × 10?5 µmol/(cm2‐s), Km = 2.6 mM. The absorptive permeability of LY544344 was reduced to approximately 5% of control in the presence of excess Gly‐Sar, a known PEPT1 substrate. Intracellular accumulation of LY354740 and LY544344, estimated postperfusion, showed high levels of LY354740 over LY544344 at all perfusate concentrations studied. However, there was a decline in the intracellular ratio of LY354740 to LY544344 at higher concentrations, suggesting that the metabolic activation to release LY354740 is saturable. © 2009 Wiley‐Liss, Inc. and the American Pharmacists Association J Pharm Sci 99: 1574–1581, 2010  相似文献   
26.
We investigated whether structural white matter abnormalities, in the form of disruption of axonal coherence and integrity as measured with diffusion tensor imaging (DTI), constitute an underlying pathological mechanism of idiopathic dystonia (ID), independent of genotype status. We studied seven subjects with ID: all had cervical dystonia as their main symptom (one patient also had spasmodic dysphonia and two patients had concurrent generalized dystonia, both DYT1‐negative). We compared DTI MR images of patients with 10 controls, evaluating differences in mean diffusivity (MD) and fractional anisotropy (FA). ID was associated with increased FA values in the thalamus and adjacent white matter, and in the white matter underlying the middle frontal gyrus. ID was also associated with increase in MD in adjacent white matter to the pallidum and putamen bilaterally, left caudate, and in subcortical hemispheric regions, including the postcentral gyrus. Abnormal FA and MD in patients with ID indicate that abnormal axonal coherence and integrity contribute to the pathophysiology of dystonia. These findings suggest that ID is not only a functional disorder, but also associated with structural brain changes. Impaired connectivity and disrupted flow of information may contribute to the impairment of motor planning and regulation in dystonia. © 2006 Movement Disorder Society  相似文献   
27.
Summary   Epileptic psychoses reflect a fundamental disruption in the fidelity of mind and occur during seizure freedom or during or after seizures. The psychotic symptoms in epilepsy share some qualities with schizophrenic psychosis, such as positive symptoms of paranoid delusions and hallucinations. Psychotic syndromes in epilepsy are most common but not exclusively associated with temporal lobe epilepsy. De Novo psychosis following epilepsy surgery is rare. Forced normalization—psychosis associated with dramatic reduction of epileptiform activity or seizures is described in small series only. Ictal and postictal psychosis can be prevented with seizure control, but postictal and chronic interictal psychoses require multidisciplinary and psychopharmacologic management.  相似文献   
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A woman with severe cicatricial conjunctival changes secondary to allopurinol-induced Stevens-Johnson syndrome developed bilateral palpebral conjunctival cysts. Pathologic examination of these lesions revealed respiratory-like pseudostratified ciliated epithelium in the walls of several cysts of one eye. To our knowledge, this is the first report of this phenomenon.  相似文献   
30.
We report an unusual large, multicystic, posterior fossa neuroepithelial neoplasm involving the cerebellum, brain-stem, and quadrigeminal cistern of a 9-month-old girl. The neoplasm consisted of variably sized, sharply demarcated nests of small cells with a high nuclear-cytoplasmic ratio and moderately basophilic nuclei, embedded in a desmoplastic, immature-appearing, mesenchymal stroma. The nests contained mitoses but none were seen in the stroma. Glial fibrillary acidic protein (GFAP), neurofilament protein, synaptophysin, and cytokeratin (AE-1) were expressed in the nests. Mesenchymal cells were negative for neural markers but positive for vimentin and desmin. The neoplasm was interpreted as a mixed mesenchymal and primitive neuroectodermal tumor (PNET) with histologic features reminiscent of a recently described intraabdominal desmoplastic small cell tumor. The tumor responded poorly to chemotherapy and a second operation was performed 1 year later. The second specimen bore no resemblance to the original and consisted of epithelial-like nests and clusters of neoplastic cells frequently interrupted by sinusoidal vessels. Tumor cells had medium-sized vesicular nuclei with small nucleoli, and a granular cytoplasm. Occasional less cellular islands of neuropil-like tissue contained larger cells having eccentric, vesicular nuclei with prominent nucleoli and abundant pink cytoplasm. Mitoses were not conspicuous. Many cells expressed synaptophysin, neurofilament protein, and GFAP. Neurofilament protein was strongly positive in the larger, neuron-like cells and synaptophysin stained the neuropil-like areas strongly but was less prominent in the neuronal perikarya. Unexpectedly, the neuropil-like areas expressed epithelial membrane antigen, whereas the neuronal cells were negative for chromogranin A. The peculiar histologic picture, combination of phenotypic markers, and remarkable biologic behavior of this unusual tumor defies classification according to existing nomenclature and exemplifies the broad range of phenotypes expressed by primitive neuro-epithelial neoplasms.  相似文献   
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