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71.
I.M. Kapetanovic J.A. Crowell R. Krishnaraj A. Zakharov M. Lindeblad A. Lyubimov 《Toxicology》2009,260(1-3):28-36
Standardized green tea extract was evaluated for exposure and toxicity in Beagle dogs following oral dosing by capsules. The main component (−)-epigallocatechin gallate (EGCG) accounted for 56–72% of the material. A 9-month chronic study (0, 200, 500, and 1000 mg/kg/day) was done in fasted dogs to take advantage of the reported improved catechin bioavailability with fasting. Extensive morbidity, mortality, and pathology of many major organs led to its early termination at 6.5 months and prevented identification of the toxicity mechanisms. A follow-up 13-week study examined the exposure to and toxicity of the extract. In general, toxicities were less severe than in the chronic study during the same interval. Dosing in a fed state resulted in considerably lower and less variable exposure than found under fasted conditions. Toxicity was less frequent and of lesser severity with lower exposure but limited sample size and large variability prevented reaching that definitive conclusion. Differences in mortality and morbidity between the preliminary terminated chronic and follow-up subchronic studies with the same dose of the same drug lot and similar exposure were not fully resolved as there may be other as yet unclear confounding factors. 相似文献
72.
PL Kogon Jerry Tchoryk Owen Fleming 《The Journal of the Canadian Chiropractic Association》1987,31(4):191-192
Pellegrini-Stieda disease is a condition occasionally observed on routine radiographic examinations of the knee. A literature survey revealed little in the way of explanation or therapeutic management of this disorder. An overview of this condition with an emphasis on etiological theory and treatment is offered along with two classic radiographic examples. 相似文献
73.
M L Auber J I DeHaven P C Raich J S Rogers E B Crowell P Romero E J Mahin J T Sosnowski D L Lamm 《The West Virginia medical journal》1991,87(8):344-346
Interleukin-2 (IL-2) is a substance produced by activated blood cells called helper T-lymphocytes and has been shown to stimulate the body's immune system. IL-2 may cause certain tumors to regress when administered intravenously to laboratory animals and humans. Lymphokine activated killer (LAK) cells are white blood cells that have been stimulated with IL-2 in vitro. LAK cells are capable of killing tumor cells both in vitro and in vivo, especially when given along with IL-2. Although this form of treatment has been found to be effective in patients with certain cancers who no longer benefit from standard forms of therapy, the anti-cancer effects of IL-2/LAK cell treatment are limited by the serious, life-threatening side effects of high-dose intravenous administration, and by the high cost. A treatment program with low-dose, intralymphatically-administered LAK/IL-2 in patients with advanced cancer is a promising alternative which circumvents these major problems and concerns, while maintaining high response rates. 相似文献
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Three examples of human plasma-derived concentrates, intermediate- purity factors VIII and IX, and fibrinogen were spiked with tissue culture-grown human immunodeficiency virus type 1 (HIV-1) strain RF. All examples were freeze-dried and heated at 80 degrees C for 72 hours by using validated production process models. HIV-1 infectivity was measured by a syncytial infectivity assay in C8166 cells and then compared with levels determined by nested HIV polymerase chain reaction (PCR). The infectivity assay demonstrated a reduction index of at least 4.5 log10, while PCR showed an average 1.7 log10. Large amounts of HIV- 1 RNA (10(5)) were still detectable by PCR in samples in which infectivity assays failed to detect any HIV-1. These data suggest that HIV-1 PCR levels do not parallel HIV-1 infectivity levels during virus- inactivation procedures involved in coagulation factor concentrate production. PCR was able to detect the RNA associated with inactivated HIV-1 particles in the factor concentrates, which allows the conclusion that PCR is not a useful test with which to monitor virus-inactivation procedures such as heating at 80 degrees C for 72 hours. This judgment contrasts with the more definite and sensitive role of PCR in diagnosing HIV-1 infection in patients in whom a positive HIV-1 PCR result correlates with active HIV-1 infection and with PCR's usefulness in monitoring virus removal. 相似文献
80.
Bibb SC Malebranche M Crowell D Altman C Lyon S Carlson A Miller S Miller T Rybarczyk J 《Journal of continuing education in nursing》2003,34(1):39-45
BACKGROUND: Focus groups were used to determine what factors need to be considered when designing a professional development program for RNs practicing at a military community hospital. METHOD: Six focus groups were formed with RNs from multiple directorates and settings within various specialties. FINDINGS: Five thematic groupings were identified: 1) specific professional development needs for leadership, clinical/specialty practice, competence development, and maintenance, 2) methods for providing continuing education, 3) methods for evaluating the effectiveness and efficiency of continuing education, 4) barriers to professional development, and 5) professional development issues impacting retention of military nurses. CONCLUSION: The professional development needs of RNs practicing in military hospitals are complex and multifaceted. The thematic groupings identified guided the design of a professional development program for RNs. 相似文献