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1.
While factors such as gender and SES have been studied as moderators of stress for children, their perceptions of control have received little attention. In the current study, children's domain-specific perceptions of their control during marital conflict were investigated as potential moderators of the impact of family stress on children's behavior problems, and perceptions of competence. Ninety-four children aged 6-12 years and mothers from families ranging in level of parental conflict from nondiscordant to discordant to physically violent were interviewed. Multiple regression analyses revealed that higher levels of conflict control beliefs acted as compensatory moderators of stress, being associated with lower levels of problem behaviors across stress levels. However, higher conflict control beliefs acted as vulnerability moderators with regard to children's perceptions of competence.  相似文献   
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The cytotoxicity of the anti-leukaemia drug amsacrine (m-AMSA) has been suggested to result from its oxidative metabolism to the corresponding quinonediimine, N1'-methanesulphonyl-N4'-(9-acridinyl)-3'-methoxy-2',5'-cyclohexad iene-1',4'- diimine (mAQDI). The metabolic fate of mAQDI was examined in cultured CHO cells (subline AA8) to identify the end products to be expected following oxidative metabolism of m-AMSA. [Acridinyl-G-3H]-m-AQDI was rapidly accumulated by AA8 cells in phosphate buffered saline with complete conversion in less than one minute to m-AMSA, macromolecular adducts and polar low molecular weight species, each of these three classes being formed in approximately equal amounts. Two of the polar products were chromatographically identical to those formed on reaction of m-AQDI with reduced glutathione. These were identified by 1H NMR spectroscopy as the 1,4-addition product 5'-(S-glutathionyl)-m-AMSA and the previously unreported isomeric 6'-(S-glutathionyl)-m-AMSA. These thiol adducts were also formed rapidly from m-AQDI in deproteinized cell lysates indicating a non-enzymatic process, although the possibility of enzymatic catalysis in intact cells has not been eliminated. The absence of such products in AA8 cells after treatment with m-AMSA places an upper limit of 1% per hour on the rate of its oxidative metabolism in these cells and suggests that generation of m-AQDI is unlikely to be responsible for the cytotoxicity of m-AMSA in cultured tumour cells.  相似文献   
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Abstract: For the women with early-stage breast cancer who are candidates for breast conservation therapy, re-excision of the primary tumor bed has commonly been used in patients for several indications. These indications include positive margin or uncertain margin status of the primary excision or residual microcalcifications on postbiopsy mammogram. If the pathology from the re-excision does not confirm negative margin status, mastectomy is generally recommended. This article examines patients who have undergone a second re-excision (i.e., a lumpectomy followed by two re-excisions) who have been treated with breast conservation therapy rather than a mastectomy.
From September 1977 to November 1995, 1,562 patients underwent breast conserving therapy at this institution. Seven hundred forty of these patients underwent a re-excisional biopsy because of positive or uncertain margin status or residual microcalcifications after the first excision. Four patients (0.5%) underwent a second re-excision because of positive or uncertain margin status or residual microcalcifications on mammogram after the first re-excision. The final margin status after the second re-excision of all four patients was negative. The radiation dose was 4,600–5,000 cGy to the whole breast followed by a conedown to bring the total dose to 6,400–6,800 cGy to the primary tumor bed.
Follow-up in the four patients was 13 years, 4 years, 14 months, and 8 months respectively. All four patients are clinically without disease and have not had a locoregional recurrence. Cosmesis was excellent in all four patients. One patient had an adriamycin-induced recall reaction causing a cellulitis, which resolved with antibiotics. There were no other complications.
Highly selected patients may undergo breast-conserving therapy after a second re-excision. Good outcome and cosmesis can be achieved for this small subset of patients with avoidance of a mastectomy.  相似文献   
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Tumour cells may express urokinase type plasminogen activator (u-PA). This may influence the invasive properties of the cells but has seldom been implicated in production of a systemic bleeding state. Two patients are described in whom severe bleeding occurred in association with disseminated malignancies. Thrombin generation was little disturbed and platelet numbers were insufficient to account for the bleeding. Florid plasmin generation was evident in the circulation and the fibrinolytic inhibitor tranexamic acid controlled the bleeding well. Free active u-PA was demonstrated in the circulation and u-PA antigen on the malignant cells which invaded the marrow of one of the patients. Tumour cell u-PA may occasionally be responsible for a bleeding state.  相似文献   
6.
Mobile phone social networking applications such as GRINDR are potential tools for recruitment of men who have sex with men (MSM) for HIV prevention research. Demographics and sexual risk behaviors of men recruited through GRINDR and through traditional media were compared. GRINDR participants were younger (mean age 31 vs. 42, p?<?0.0001), more White identified (44 vs. 30?%, p?<?0.01), and had more sex partners in the previous 14 days (1.88 vs. 1.10, p?<?0.05) than other recruits. Email responses were less successful for enrollment than phone calls (5 vs. 50?%). This approach resulted in successful recruitment of younger and more educated, White identified MSM.  相似文献   
7.
Liotti proposed that interactions during infancy with a parent suffering unresolved loss could lead to vulnerabilities to altered states of consciousness. Hesse and van IJzendoorn provided initial support for Liotti’s hypothesis, finding elevated scores on Tellegen’s Absorption Scale - a normative form of dissociation - for undergraduates reporting that their parents had experienced the loss of family members within two years of their birth. Here, we replicated the above findings in a large undergraduate sample (N = 927). Additionally, we investigated mother’s and father’s losses separately. Perinatal losses, including miscarriage, were also considered. Participants reporting that the mother or both parents had experienced loss within two years of their birth scored significantly higher on absorption than those reporting only perinatal, only father, or no losses. While not applicable to the assessment of individuals, the brief loss questionnaire utilized here could provide a useful addition to selected large-scale studies.  相似文献   
8.
Rejection sensitivity is a cognitive-affective processing disposition that has been linked to interpersonal difficulties. In this regard, the neuropeptide hormone, oxytocin, is thought to underlie social cognitions and behaviors that promote social affiliation. A single nucleotide polymorphism (SNP) on the oxytocin receptor gene (OXTR), in which guanine (G) is substituted for adenine (A), has been associated with less support-seeking behaviors. In the current study, among 376 undergraduate students, it was shown that the relationship between rejection sensitivity and depressive symptoms was mediated by multiple group memberships. Furthermore, the relation between rejection sensitivity and group memberships was only evident among individuals possessing the A allele on the OXTR gene. These findings further support the psychosocial deficits characteristic of individuals possessing the OXTR polymorphism, which in turn is linked to poor mood.  相似文献   
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