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Nurses historically have accepted the risk of contagion while caring for patients with infectious diseases. The duty to care for patients is directly related to the care the patient requires, the nurse's knowledge, and the extraordinary risk to the nurse. The current infection with human immunodeficiency virus (HIV) and acquired immunodeficiency syndrome (AIDS) highlights other factors, such as fear, ignorance, and homophobia, that influence a nurse's decision to refuse to provide care. Professional associations, nurse administrators, and educators must assist nurses to gain the knowledge and skill necessary to provide care as well as explore feelings about different life-styles.  相似文献   
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Subcutaneous tumours were induced in castrated golden Syrian hamsters by 7,12 dimethylbenz[a]anthracene (DMBA), an agent known to produce papillomas and carcinomas. The morphological characteristics of the cellular and extracellular constituents of the chemically-induced tumours were indicative of melanoma. Tumours were induced by three injections of DMBA into the jugular vein over a 3 month period. Dermal tumour development within the dorsal integument and groin region ultimately projected into the epidermis and occurred during the 3 month period subsequent to the last DMBA injection. Suspect melanoma tumours were excised and processed for light microscopic (LM) and transmission electron microscopic (TEM) studies. Histochemical staining methods facilitated the characterization of the differentiated tumour components in this hamster melanoma model. The model presented could allow observations from initial melanoma transformation events through advanced stages of metastasis within a window of 7 months.  相似文献   
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BACKGROUND: The role of intravenous (IV) albumin administration in the prevention of ovarian hyperstimulation syndrome (OHSS) and in the improvement of IVF conception outcomes was evaluated in a prospective, randomized, placebo-controlled double blind study. METHODS: Ninety-eight women were enrolled in the study and were consecutively assigned to either a treatment group or a control group. Eleven patients were lost to follow-up after assignment. Of the remaining 87 women, 46 received albumin on the day of oocyte retrieval, and 41 received 0.9% sodium chloride solution as a placebo control. Outcome measures included OHSS incidence rates and pregnancy rates in the two trial groups. RESULTS: Four of the 46 patients in the study group developed severe OHSS and six developed moderate OHSS. In the control group, one of the 41 developed severe OHSS and five developed moderate OHSS. The difference in OHSS incidence rates between the two groups was not statistically significant [relative risk (RR) = 1.49, 95% CI = 0.59-3.73]. Fourteen patients (30%) in the intervention group conceived, compared with 16 patients (39%) in the control group. The difference in conception rates between the two groups was not statistically significant (RR = 0.78, 95% CI = 0.44-1.39). CONCLUSIONS: Albumin appears to have no positive effect on OHSS or conception rates, while its use carries the risk of undesirable side effects, including exacerbation of ascites in OHSS, nausea, vomiting, febrile reaction, allergic reaction, anaphylactic shock and risk of virus and prion transmission. We suggest that this form of treatment should not be included in the prevention of OHSS.  相似文献   
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BACKGROUND: Anti-Mullerian hormone (AMH) is expressed in pre- and small-antral follicles. High serum levels are found in women with polycystic ovaries (PCO), accordant with their increased content of small follicles. To evaluate the relationship between AMH, folliculogenesis and hyperandrogenism, we compared serum AMH levels between women with PCO with and without hyperandrogenism and normal controls during controlled ovarian hyperstimulation (COH). METHODS: Nineteen women with PCO and hyperandrogenism (group A), 10 women with PCO but no hyperandrogenism (group B) and 23 ovulatory women with normal ovarian morphology (group C, controls) underwent COH with the long protocol. Serum levels of AMH, estradiol, androstenedione and follicular tracking were determined before gonadotropins treatment (day 0) and every 2-4 days up to the day of HCG administration. RESULTS: AMH levels declined gradually throughout COH in the three groups, but remained higher in groups A and B compared with the controls. Significantly higher levels were found in group A compared with group B, despite comparable numbers of small follicles. Multiple regression analysis revealed that both the number of small follicles and serum androgens were correlated to AMH. CONCLUSIONS: Women with PCO have higher serum AMH levels during COH than controls. Hyperandrogenism is associated with an additional increase in AMH. It is conceivable that hyperandrogenism may reflect more severe disruption of folliculogenesis in women with PCO or may affect AMH secretion.  相似文献   
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Background  

Painless, rapid, controlled, minimally invasive molecular transport across human skin for drug delivery and analyte acquisition is of widespread interest. Creation of microconduits through the stratum corneum and epidermis is achieved by stochastic scissioning events localized to typically 250 μm diameter areas of human skin in vivo.  相似文献   
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Electrophoretic analysis of the serum from a patient Im suffering from a multiple myeloma revealed the existence of two abnormal bands. Purification of these two fractions on a DEAE—cellulose column showed that both fractions had the same sedimentation coefficient (7S), belonged to the same class (IgG), and subclass (γl) and bore the same allotype (Gm1). However, the heavy (H) chains of one immunoglobulin were associated with type κ light (L) chains whereas those of the other were associated with type λ L chains.Three individual antigenic determinants were found in these two proteins. One was common to the H chains of both proteins and the other two were each specific to one of the L chains. These results suggest that the myeloma cells of patient (Im) were able to produce at least three polypeptide chains, one H chain and two different types of L chains.  相似文献   
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Huerta  S.  Tran  N.  Yi  B.  Pham  T. 《Hernia》2021,25(5):1289-1294
Hernia - The optimal approach for inguinal hernia repair in the obese remains elusive. Minimally invasive techniques show equivocal results compared to the open method. None of the current analyses...  相似文献   
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