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131.
Narrative analysis of sexual etiquette in teenage magazines   总被引:1,自引:0,他引:1  
Expanding on existing research on women's magazines, this essay examines the sexual etiquette developed in advice columns in magazines popular among teenage women. Over a span of 20 years, the advice has changed very little. Serving the rhetorical function of field guides and training manuals, teen magazines limit women's sociality and sexuality within narrowly defined heterosexual norms and practices. The rhetoric of sexual etiquette encourages young women to be sex objects and teachers of interpersonal communication rather than lovers, friends, and partners. Young women are being taught to subordinate self for others and to be contained.  相似文献   
132.
Tumor necrosis factor-alpha (TNF-alpha) is thought to be an important mediator in the pathogenesis of neonatal septicemia. To assess the role of TNF-alpha in neonatal sepsis, serum levels of TNF-alpha were measured in a group of neonates with septicemia and compared with the levels of gestational-postnatal, age-matched healthy controls. The relationships between severity of infection, the nature of causative microorganisms, and TNF-alpha levels were also investigated in this prospective study. A total of 49 infants (25 full-term, 24 preterm) with proven sepsis and 40 healthy infants (20 full-term, 20 preterm) were included. Serum TNF-alpha levels were measured using the TNF-alpha immunoradiometric assay. The median level of TNF-alpha was found to be significantly higher in infants suffering from sepsis (154 pg/mL) particularly in those with septic shock (242.5 pg/mL) as compared to healthy controls (61.5 pg/mL) (p < 0.001). No correlation was found between TNF-alpha and postnatal ages, gestational ages or birth weights of the infants. TNF-alpha levels were not different in surviving and terminal neonates. Although serum, TNF-alpha levels were found to be slightly higher in gram-negative septicemia, the difference was not significant. These findings suggest that TNF-alpha plays an important role in the pathophysiology of neonatal septicemia, but its importance as a prognostic factor is not yet clear.  相似文献   
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Monitoring the frequency of the Philadelphia (Ph) chromosome in chronic myelogenous leukemia (CML) is important in determining the effectiveness of treatment for patients during therapy. This can be done with high resolution by subjecting short-term bone marrow cultures (48 h) to 24 h of mitotic arrest before harvest and detecting Ph-positive (Ph+) metaphases by fluorescence in situ hybridization (FISH) in a procedure termed hypermetaphase FISH or HMF. Here, we compared procedures for detecting Ph+ interphase cells (interphase FISH or I-FISH) in peripheral blood polymorphonucleocytes (PMNs) with HMF results on the bone marrow of the same 26 CML patients in different stages of remission. The probes for I-FISH in these experiments were relatively large (200-300 kb) and sufficiently resolved in PMNs so that 97.5% of the cells were scorable. The correlation between the frequencies of Ph+ cells from the two different cell sources was excellent (r = 0.983, P < 0.0001); however, there was a consistently higher level of Ph+ cells observed in the cycling marrow cells than in the peripheral blood PMNs. This was discussed in terms of current theories of apoptosis in CML cells. The large number of PMNs analyzable by I-FISH (approximately 500/patient in this study) provided sufficiently narrow 99% confidence intervals to suggest the procedure as an effective and efficient method for monitoring the frequency of Ph+ cells in CML patients undergoing therapy. However, for detection and quantification of minimal residual disease, HMF is preferable to I-FISH because of the much lower frequency of false-positive readings with the former procedure.  相似文献   
137.
PURPOSE: To perform a preliminary evaluation of the diagnostic accuracy of contrast-enhanced, two-dimensional (2D) magnetic resonance (MR) digital subtraction angiography (DSA) of the lower extremity by comparison with x-ray angiography (XRA). MATERIALS AND METHODS: Forty lower extremities in 22 patients were imaged at multiple levels with both XRA and 2D MR DSA. Images were retrospectively analyzed by three radiologists in a randomized blinded manner. Seventeen vascular segments were graded as an insignificant lesion, a significant lesion, or as an occlusion. With the use of segments well depicted with XRA as the gold standard, the sensitivity, specificity, and accuracy of 2D MR DSA, as compared with XRA, were evaluated. The McNemar-Stuart-Maxwell test was performed to determine the significance of any differences found. RESULTS: Three hundred eighty-three arterial segments were evaluated with both techniques. Three hundred one segments were well depicted with XRA. There was no significant difference between 2D MR DSA and XRA for assessing the degree of occlusive disease in these 301 segments (.25 < P < .5). The sensitivity, specificity, and diagnostic accuracy of 2D MR DSA were found to be 90%, 98%, and 93%, respectively. CONCLUSION: Two-dimensional MR DSA is an accurate method for assessing arterial lesions in the lower extremity.  相似文献   
138.
A Schistosoma mansoni cercarial cDNA expression library, constructed in lambda gt11, was screened using the IgG fraction of sera taken from rabbits vaccinated with irradiated cercariae. A positive cDNA clone (1,431 base pairs) was selected and characterized. The amino acid sequence predicted from the cDNA sequence identified a polypeptide of 363 amino acids that showed significant homology to different family members of the enzyme fructose-1,6-bisphosphate aldolase (EC 1.4.2.13). The identity was 66% and 65% with human C and A isoenzymes, respectively. Active sites and substrate-binding determinant analysis suggest that the isolated enzyme in terms of function resembles type A aldolase. The recombinant protein expressed in the vector pGEX-2T was found to be active enzymatically. Antibodies raised against the purified recombinant protein recognized a 40-kDa band in extracts from cercariae, schistosomula (5 and 25 days), adult worms, and eggs. Using immunocytochemistry, aldolase localized to the tegumental region of the adult worms.  相似文献   
139.
Ventilation with nitric oxide (NO) is increasingly being used to treat pulmonary hypertension in the newborn. In the brain, NO has vasoactive properties and is involved in neurotransmission. However, the effect of inhaled NO on the cerebral blood flow (CBF) and on the cerebral activity is not known. Furthermore, there is little information on the influence of this free radical gas on the redox status in pulmonary vessels. We therefore investigated the effect of inhaled NO (2-60 ppm) on CBF, cerebral activity and redox status in blood effluent from the pulmonary circulation in 6 ventilated newborn lambs before and during group B streptococci (GBS)-induced pulmonary hypertension. Blood pressure in the pulmonary artery (P(ap)) and aorta (Pao), carotid artery blood flow (Qcar) to assess changes in CBF, and electrocortical activity were measured. Blood gases, indices of free radical status and methemoglobin were determined in blood samples obtained from the left ventricle. Inhalation of NO, before and during GBS-induced pulmonary hypertension, decreased P(ap) and PCO2 and increased PO2. Multiple linear regression revealed that Qcar was positively related to PCO2, but not to inhaled NO or PO2 before or during GBS conditions. Electrocortical activity and indices of antioxidative capacity and lipid peroxidation did not change significantly. Methemoglobin was not detected. In conclusion, inhalation of NO (up to 60 ppm) lowered P(ap) without directly affecting CBF, electrocortical activity, and redox status in the pulmonary vessels. CBF, however, can indirectly be influenced by NO-mediated changes in PCO2.  相似文献   
140.
Chronic food restriction reduces blood pressure (BP) and sympathetic support of BP in aortic coarctation hypertension. The purpose of this study was to test the hypothesis that chronic food restriction would reduce sympathetic support of BP mediated by the paraventricular hypothalamic nuclei (PVN). Hypertension was induced in male Sprague-Dawley rats (n=40) by suprarenal aortic coarctation. Rats were assigned to either an ad libitum fed (AL) group or a food restricted (FR) group that received 60% of the food consumed by AL for 3 weeks. One week prior to data collection, catheters were implanted in the left carotid artery and right jugular vein. BP was measured for 2 days prior to, and 7 days after rats in AL and FR groups received either bilateral electrolytic lesions of the PVN (PVNx) or sham lesions (SHAM). Prior to either PVNx or SHAM, FR rats had significantly lower BP (AL=152+/-5; FR=113+/-2 mmHg), less of a depressor response to ganglionic blockade (AL=-58+/-4; FR=-35+/-2 mmHg), and lower plasma norepinephrine levels (AL=758+/-71; FR=380+/-23 pg/ml) compared to AL. PVNx reduced BP in both AL and FR rats (AL-PVNx=105+/-6 mmHg, FR-PVNx=101+/-3 mmHg). PVNx also lowered the depressor response to ganglionic blockade (AL-PVNx=-28+/-5 mmHg, FR-PVNx=-29+/-4 mmHg) and plasma norepinephrine levels (AL-PVNx=372+/-74 pg/ml, FR-PVNx=248+/-31 pg/ml). FR decreased the magnitude of the reductions in resting BP and in sympathetic activity in response to PVNx. These results indicate that intact PVN are required for maintenance of aortic coarctation hypertension, and implicate the PVN as a site involved in BP reductions produced by chronic food restriction.  相似文献   
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