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51.
Broiler chicks were provided choices of synthetic diets (a) adequate or low in lysine, and (b) adequate in or devoid of lysine. In each case, chicks consumed some of each diet offered, but preference was shown for the adequate lysine diet. Growth rates of chicks given choices ranged from 80% of that of chicks fed an adequate lysine diet with no choice for two weeks, then growth rates fell to about 60% of those fed adequate lysine. In another study, chicks were fed a diet devoid of lysine but were offered pure L-lysine HCl in a separate feeder. These chicks selected some of the supplementary lysine, but their body weights were only 68% of the body weight of chicks fed an adequate lysine diet after 21 days. Chicks given a choice of diets prepared with an adequate quantity of either L- or D-lysine preferred with L-lysine diet but did not select sufficient quantity to reach normal growth. These observations indicate that chicks can discern the presence of L-lysine in diets or separately, but will not select sufficient quantity for maximum growth potential. A diet prepared with D-lysine was more acceptable than one completely devoid of lysine, suggesting some sensory recognition for lysine. 相似文献
52.
Jackie Robinson Rosemary Frey Deborah Raphael Andrew Old Merryn Gott 《Health & social care in the community》2022,30(1):133-141
A generalist–specialist model of palliative care is well established as a framework for the provision of community care in resource-rich countries. However, evidence is lacking regarding how the model is experienced by family carers and the extent to which access to both generalist and specialist palliative care is equitable. A cross-sectional postal survey was undertaken to explore bereaved family's experiences of generalist palliative care and its intersection with hospice services in the last 3 months of life. A modified version of the Views of Informal Carers—Evaluation of Services survey was sent to 4,778 bereaved family. Data were collected between February 2017 and October 2018. Chi-square was utilised to identify factors that impacted on experiences of generalist palliative care; analysis of free text data comprising 45,823 words was undertaken using a directed content analysis approach. Eight hundred and twenty-six questionnaires were returned (response rate = 21%). Seventy per cent of people (n = 579) spent some time at home in the last 3 months prior to death. People who received support from hospice were more likely to receive support from multiple other services. Those who received no community services were less likely to feel supported by their general practitioner, less likely to spend the last 2 days of life or die at home. Feeling supported had a strong association with services working well together, being involved in decision-making and being aware of the poor prognosis. The provision of palliative care is complicated by a lack of integration with specialist palliative care and may be the basis of continuing inequities in the provision of community care at the end of life. The assumption at a policy level that “generalists” are willing and able to play a key role in palliative care provision needs to be further challenged. 相似文献
53.
Triplett Noah S. Woodard Grace S. AlRasheed Rashed Meza Rosemary D. Robinson Sophia Berliner Lucy Dorsey Shannon 《The journal of behavioral health services & research》2021,48(4):617-624
The Journal of Behavioral Health Services & Research - Characterizing community mental health (CMH) treatment duration and discharge is an important step toward understanding how to better meet... 相似文献
54.
Clostridium perfringens is a normal bacterial flora of the small and large intestines of humans and other animals. The current study investigates the potential use of a noncytotoxic C. perfringens as an oral vaccine vehicle for expression and intestinal delivery of a large amount of SIV antigens. Here we report the construction of a recombinant C. perfringens vaccine vector expressing high levels of SIV p27 during sporulation. Following oral administration of this recombinant C. perfringens vaccine vector to mice, large amounts of intact p27 protein were detected in the terminal ileum where the majority of Peyer's Patches (PPs) are located. Furthermore, dendritic cells (DCs) beneath the mucosal surface in the PPs were able to capture SIV p27 antigen, when PPs were exposed to C. perfringens expressing SIV p27 antigen. In addition, uptake of C. perfringens was able to induce maturation of mouse DCs. These results support the potential use of C. perfringens as an oral SIV/HIV vaccine vector. 相似文献
55.
56.
Interaction of family history of breast cancer and dietary antioxidants with breast cancer risk (New York,United States) 总被引:1,自引:0,他引:1
Christine B. Ambrosone James R. Marshall John E. Vena Rosemary Laughlin Saxon Graham Takuma Nemoto Jo L. Freudenheim 《Cancer causes & control : CCC》1995,6(5):407-415
We sought to determine if specific dietary antioxidants may be particularly effective in reducing breast cancer risk for women reporting family history (FH) of breast cancer in a first-degree relative. Interviews regarding usual diet, health, and family histories were conducted with 262 premenopausal and 371 postmenopausal women with incident, primary breast cancer from western New York (United States). These women were frequencymatched by age and county of residence with community controls. Among premenopausal women, there was a significant interaction between FH and -tocopherol; -tocopherol was associated with significantly decreased risk among FH+ women (adjusted fourth-quartile odds ratio [OR]=0.01, 95 percent confidence interval [CI]=0.0–0.3). This association was much weaker for FH-women [OR=0.7, CI=0.4–1.2]. For FH-women, a significant inverse association was observed between -carotene and premenopausal breast-cancer risk (OR=0.4, CI=0.3–0.5), but not for FH+ women (OR=0.5, CI=0.1–4.0). Similar relationships, although not as strong, were noted among postmenopausal women. Although limited by small numbers, these results suggest that biologic mechanisms of tumorigenesis may differ in FH+ and FH-women, and that -tocopherol may be a potential chemopreventive agent for women with a family history of breast cancer, particularly premenopausal women.This research was conducted by the Department of Social and preventive Medicine, State University of New York at Buffalo. This publication is supported in part by grants CA11535 and 5 R25 CA1820117 from the US National Cancer Institute and PDT-434 from the American Cancer Society. Dr Freudenheim is a recipient of a Research Career Development Award from the National Cancer Institute (CA01633). This work is solely the responsibility of the authors and does not necessarily represent the views of the NCI. 相似文献
57.
Rosemary Dziak 《Calcified tissue international》1978,26(1):65-70
Summary The vitamin D3 metabolite, 25-hydroxycholecalciferol, at concentrations of 0.01 to 10.0 g/ml, decreased calcium uptake by isolated bone cells. The effect occurred within 1 min after the simultaneous addition of metabolite and45Ca. Lactic acid and ATP production by the cells was not affected. 24(R), 25-dihydroxycholecalciferol produced a similar decrease in calcium uptake. Vitamin D3 had no effect at concentrations from 0.01 to 10.0 g/ml. No effect of 1,25-dihydroxycholecalciferol on calcium uptake was observed with concentrations from 0.1 to 100 ng/ml and various preincubation periods extending to 2 h. None of the agents had any effect on calcium efflux. The effects of 25-hydroxycholecalciferol and 24(R), 25-dihydroxycholecalciferol on calcium uptake were not seen in isolated fetal rat skin cell preparations. 相似文献
58.
Rosemary C. Baggish Amy Wheaton Sheila W. Wellington 《Administration and policy in mental health》1981,8(3):194-201
The use of short-term isolation (STI) in a children's psychiatric hospital was examined using the Joint Commission on Accreditation of Hospitals (JCAH) quality assurance mode. A Clinical Care Evaluation addressed two questions: Are we providing quality use of STI? And are we adequately documenting its use? A medical record audit of 78 discharged patients and a review of unit records provided hospital staff with utilization and demographic statistics; structured interviews with staff and inpatients were conducted that provided information about their opinions of STI. The data gathered served as the basis for recommendations that led to planned, informed program changes. 相似文献
59.
Tai K. Yeung John W. Hopewell Rosemary H. Simmonds Leonard W. Seymour Ruth Duncan Ornella Bellini Maria Grandi Federico Spreafico Jiri Strohalm Karel Ulbrich 《Cancer chemotherapy and pharmacology》1991,29(2):105-111
Summary A rat model was used to evaluate the general acute toxicity and the late cardiotoxicity of 4 mg/kg doxorubicin (DOX) given either as free drug or in the form of threeN-(2-hydroxypropyl)methacrylamide (HPMA) copolymer conjugates. In these HPMA copolymers, DOX was covalently bound via peptide linkages that were either non-biodegradable (Gly-Gly) or degradable by lysosomal proteinases (Gly-Phe-Leu-Gly). In addition, one biodegradable conjugate containing galactosamine was used; this residue was targeted to the liver. Over the first 3 weeks after the i.v. administration of free and polymer-bound DOX, all animals showed a transient reduction in body weight. However, the maximal reduction in body weight seen in animals that received polymer-bound DOX (4 mg/kg) was significantly lower than that observed in those that received free DOX (4 mg/kg) or a mixture of the unmodified parent HPMA copolymer and free DOX (4 mg/kg;P<0.01). Throughout the study (20 weeks), deaths related to cardiotoxicity were observed only in animals that received either free DOX or the mixture of HPMA copolymer and free DOX; in these cases, histological investigations revealed marked changes in the heart that were consistent with DOX-induced cardiotoxicity. Sequential measurements of cardiac output in surviving animals that received either free DOX or the mixture of HPMA copolymer and free DOX showed a reduction of 30% in function beginning at the 4th week after drug administration. The heart rate in these animals was 12% lower than that measured in age-matched control rats (P<0.05). Animals that were given the HPMA copolymer conjugates containing DOX exhibited no significant change in cardiac output throughout the study (P<0.05). In addition, no significant histological change was observed in the hearts of animals that received DOX in the form of HPMA copolymer conjugates and were killed at the end of the study. However, these animals had shown a significant increase in heart rate beginning at 8 weeks after drug administration (P<0.01). This study demonstrates that covalent binding of DOX to HPMA copolymer conjugates via both stable and biodegradable peptidyl linkages considerably reduces both the general acute toxicity and the late cardiotoxicity of DOX in the rat and could offer the potential for improving the therapeutic index in the clinical application of DOX. 相似文献
60.
A morphologic classification and incidence of spontaneous ovarian neoplasms in three strains of mice
Ovarian tumors were reviewed and classified in 5,404 control inbred BALB/c, C57BL/6, and C3H mice. In descending order of frequency, the most common types in the C3H mice were the tubular mesothelioma (adenoma), thecoma, luteoma, granulosa cell tumor, and cystadenoma. In descending order the most common types in the BALB/c mice were the luteoma, tubular mesothelioma, granulosa cell tumor, thecoma, and cystadenoma. The tubular mesothelioma was the only ovarian tumor of significance in the C57BL/6 mice. Most of the ovarian tumors were rare before 1 year of age, but they increased with age after 1 year. 相似文献