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351.
Palsy of the suprascapular nerve may be easily overlooked in the differential diagnosis of the painful shoulder. Although the diagnosis is well documented in the literature, opinion is still divided regarding its etiology and treatment. This case report offers an example of successful nonoperative management of a suprascapular nerve palsy which followed an acute episode of muscular stress in a young male athlete.  相似文献   
352.
Studies of estrogen effects on growth hormone (GH) and its pulsatile release in postmenopausal women have typically utilized estrogen replacement therapy (ERT) of relatively short duration (days to weeks). The purpose of this study was to compare GH measures from healthy postmenopausal women who were on oral ERT for 3 years or more (n = 24; mean ERT duration = 16.1 years) with women not on ERT (NERT; n = 40). Blood samples were drawn remotely every 20 min for 24 h and then analyzed for mean 24-h GH, mean GH during sleep, and mean 24-h insulin-like growth factor-I (IGF-I). GH peak analyses were also performed. Mean 24-h GH and GH during sleep were significantly higher and IGF-I was significantly lower in ERT women compared with NERT women. In addition, use of long-term ERT was associated with more GH peaks relative to women not on ERT, but no change in GH peak amplitude or area. GH was not related to age in either group. GH was strongly and negatively correlated with measures of adiposity in NERT women but not in ERT women. In conclusion, long-term oral ERT is associated with increased circulating GH and decreased IGF-I levels, even after many years of treatment.  相似文献   
353.
Gays and lesbians are becoming increasingly visible to the healthcare professional as a result of the AIDS epidemic and the growing number of lesbian mothers. Ethical practice requires that nurses have an understanding of diverse cultures but focus has historically been on racial and ethnic minorities; little research exists on those with minority sexual or affectional preferences. Heterosexism, the promotion of a heterosexual orientation as the only viable option, has much the same effect as racism. Individuals experience feelings of shame, self-hatred, and lowered self-esteem. The purpose of this article is (1) to present the current state of knowledge regarding individual identity formation and couple development in the gay and lesbian community and (2) to describe the impact of heterosexism. Implications for nursing practice and research will be explored.  相似文献   
354.
A mathematical model integrating the roles of cyclin D, cdk4, cyclin E, cdk2, E2F and RB in control of the G1 phase of the cell cycle is described. Experimental results described with murine embryo fibroblasts (MEFs), either Rb+/+ or Rb-/-, and with the RB-deficient osteosarcoma cell line, Saos-2, served as the basis for the formulation of this mathematical model. A model employing the known interactions of these six proteins does not reproduce the experimental observations described in the MEFs. The appropriate modelling of G1 requires the inclusion of a sensing mechanism which adjusts the activity of cyclin E/cdk2 in response to both RB concentration and growth factors. Incorporation of this sensing mechanism into the model allows it to reproduce most of the experimental results observed in Saos-2 cells, Rb-/- MEFS, and Rb+/+ MEFs. The model also makes specific predictions which have not been tested experimentally.  相似文献   
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Immunohistochemistry was used to examine the expression of p53 in pre-malignant oral lesions and oral squamous-cell carcinomas (SCCs) from Swedish and Sudanese snuff-dippers, as well as in pre-malignant oral lesions and oral SCCs from non-snuff-dippers from the Sudan, Sweden and Norway. Of the 14 SCCs from Sudanese snuff-dippers, 21% (3/14) expressed p53. Of the 14, 60 and 41 SCCs from non-snuff-dippers from the Sudan, Sweden and Norway, 64% (9/14), 65% (39/60) and 68% (28/41) expressed p53, respectively. A statistically significant difference in expression of p53 was found in SCCs from Sudanese snuff-dippers compared to those from non-snuff-dippers from all/or any of the 3 countries. None of the suspected pre-malignant oral lesions from Sudanese snuff dippers or non-snuff-dippers expressed p53. Only 2 out of the 15 oral fibro-epithelial hyperplastic lesions from Swedish snuff-dippers expressed p53. Some of the oral epithelial dysplastic lesions, as well as the carcinoma in situ lesions from Norwegian non-snuff-dippers, expressed p53, while the oral fibro-epithelial hyperplastic lesions did not. The low relative frequency of p53 expression found in oral SCCs from snuff-dippers compared to those from non-snuff-dippers might suggest differences in mechanisms of oncogenic action induced by snuff. Alternatively, the pathogenesis of malignant oral lesions from snuff-dippers may follow a p53-independent pathway. In view of the unusually high levels of the tobacco-specific nitrosamines (TSNA) found in the type of snuff used in the Sudan, investigations of p53 mutations or oncogenes are needed.  相似文献   
357.
358.
We investigated the mechanism of resistance in murine L1210 leukaemia cells selected after treatment with FCE 23762 methoxymorpholinyl doxorubicin: (MMRDX), a methoxymorpholinyl derivative of doxorubicin active in vitro and in vivo on multidrug-resistant (mdr) cells, currently undergoing phase I clinical trials. The resistant subline obtained after repeated in vitro treatments, L1210/MMRDX, is resistant in vitro and in vivo to all tested methoxymorpholinyl derivatives and to cyanomorpholinyl doxorubicin, but shows resistance to morpholinyl derivatives only in vivo or following their activation with rat S9-liver fractions in vitro. L1210/MMRDX cells are sensitive to classic mdr- and altered topoisomerase (AT)-mdr-associated drugs. These cells do not appear to overexpress the mdr1 gene, nor do they exhibit impaired intracellular drug accumulation and efflux or altered levels of glutathione and glutathione S-transferase. The extent of DNA single-strand break formation and, after microsomal activation, of DNA interstrand cross-links after treatment with MMRDX was similar in the parent and the resistant subline. The mechanism of resistance in L1210/MMRDX cells remains to be identified but may prove a novel one, highly specific for this class of mdr-active anthracyclines.  相似文献   
359.
360.
The authors found several common themes in intensive interviews with 20 prominent psychiatric administrators. The decision to go into administrative work resulted from strong interest in public service, frustration in other roles, and/or situational factors. Administration was learned by doing and by interaction with colleagues in the field or other knowledgeable individuals. The job of administrator is often perceived as stressful, but it offers rewards such as increased autonomy, opportunities for self-growth, prestige, and the potential for a broader contribution to mental health.  相似文献   
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