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1.
Depressed levels of circulating menaquinones in patients with osteoporotic fractures of the spine and femoral neck 总被引:3,自引:0,他引:3
S.J. Hodges M.J. Pilkington T.C.B. Stamp A. Catterall M.J. Shearer L. Bitensky J. Chayen 《BONE》1991,12(6):387-389
Vitamin K1 functions in the conversion of glutamate residues, present in certain bone peptides, into the putatively active γ-carboxyglutamate form. We have shown previously that the circulating levels of vitamin K1 are depressed in osteoporotic patients. However, it is known that menaquinones (vitamin K2:MK) may be more effective than vitamin K1 in this conversion of the inactive to active form of glutamate residues. A procedure for measuring such menaquinones has now demonstrated a marked deficiency of MK-7 and MK-8 in patients with osteoporotic fractures. It is suggested that estimates of circulating levels of K1, MK-7, and MK-8 might provide a biochemical risk marker of osteoporotic fractures. 相似文献
2.
Lucille Kingston Dianne Reynolds Linda Paine Phillips 《Journal of Midwifery & Women's Health》1995,40(2):187-201
This article reviews the pertinent anatomy of each body system involved in the assessment of the head and neck (including the eyes, ears, nose, and throat) and describes the basic elements of the comprehensive health assessment. Frequently encountered chief complaints are discussed. Aspects of the health assessment that will assist the primary care provider in making a differential diagnosis and determining the need for referral are presented. This article is the first of two articles on this topic; the subsequent article will address primary care management of common conditions of the head and neck. 相似文献
3.
Dr. David M. Euhus MD Lucille Kimura PhD Bruce Arnold MD 《Annals of surgical oncology》1997,4(5):432-439
Background: Mice immunized with murine mammary carcinoma cells genetically engineered to secrete interleukin-2 (IL-2) are rendered resistant
to subsequent challenge with unmodified tumor cells, and in the case of mice bearing established tumors, the rate of development
of pulmonary metastases is reduced. Despite these encouraging animal results, little is known about the induction of antitumor
immunity by IL-2 gene transfer in human breast cancer.
Methods: Adenovirally mediated IL-2 gene transfer was performed in 12 tumor fragment cultures established from seven primary breast
cancers. Autologous tumor infiltrating lymphocytes (TILs) or peripheral blood mononuclear cells (PBMCs) were cocultured with
transduced tumor fragments, and changes in phenotype and cytotoxicity were measured.
Results: IL-2 was never detectable in the untransduced cultures, but it peaked at 5.0—1,324.8 ng/ml in the transduced cultures. Lymphocyte
counts declined in all untransduced cultures, but they increased two- to sevenfold in four transduced cultures. CD4:CD8 ratios
decreased from a mean of 2.11 at baseline to 1.27 after stimulation in coculture (p=0.03). Expansion of lymphocytes expressing
the natural killer cell phenotype (CD3−CD56+) occurred in only one culture, but the CD3+CD56+ population increased in four of six cultures. Lymphocytes from four of 10 cocultures generated significant cytotoxicity against
allogeneic breast cancer cells. Induction of cytotoxicity correlated with expansion of the CD3+CD56+ phenotype (R2=0.805, p=0.02).
Conclusions: IL-2 gene expression by human breast cancer causes expansion of CD3+CD56+ cytotoxic lymphocytes. This phenotype is consistent with that of a non-major histocompatibility complex (MHC)-restricted
cytokine induced killer cell population previously described.
Opinions, interpretations, conclusions and recommendations are those of the author and are not necessarily endorsed by the
U.S. Army.
Presented at the 49th Annual Cancer Symposium of The Society of Surgical Oncology, Atlanta, Georgia, March 21–24, 1996. 相似文献
4.
INTRODUCTION: Health care workers have long been recognized as having a high risk of work-related assault. In response to a growing threat of violence in hospitals, California implemented the Hospital Security Act (AB508) in 1993. This study compares surveys of emergency nurses before and after implementation of AB508. METHODS: In 1990, the CAL/ENA surveyed emergency departments in California to enumerate violent events and describe security programs. Using the CAL/ENA membership directory, hospitals were resurveyed in 2000 to identify changes from the original survey. Surveys were mailed to the ED nurse manager or equivalent. Survey responses were anonymous. RESULTS: Most hospitals reported fewer violent episodes after the implementation of AB508. However, 32% of hospitals reported that 5 or more verbal threats occurred monthly, and 5% reported that 5 or more violent injuries occurred monthly. Overall, hospitals reported improvements in security programs. The most notable increase was in employee training, which rose from 34% to 95.6% of reporting hospitals. However, almost a quarter of hospitals reported not having general violence prevention policies, and many believed that security personnel were inadequate. DISCUSSION: Although results reported here cannot be directly attributed to AB508, the increase in security program components suggests that hospitals are responding positively to reduce violence. The high prevalence of threats and violent events reported indicates a persistent risk of violence against health care workers. 相似文献
5.
6.
Primm BJ Perez L Dennis GC Benjamin L Clark W Keough K Leak WD Payne R Smith D Sullivan LW;National Medical Association 《Journal of the National Medical Association》2004,96(9):1152-1161
ISSUE: Inadequate pain management is a serious public health problem that affects a wide cross-section of Americans. Patients are often denied sufficient medication, because physicians lack training and fear scrutiny from federal and state regulatory agencies. In addition, even the state-financed system of care, Medicaid, has been increasingly denying payment for the best treatment for pain management. These factors are complicated by physician bias about various subgroups and poor physician-patient communication. Comprehensive patient assessment plays a crucial role in determining appropriate treatment and identifying potential abuse problems. Physicians must routinely document medications analgesic effects and screen for potential ill effects and drug abuse. OBJECTIVE: To examine the prevalence of the undertreatment of pain, particularly among African Americans, and to recommend relevant proactive policy and practice changes to aid in eliminating this health problem. CONSENSUS PROCESS: In July 2002, the NMA convened the "Managing Pain: The Challenge in Underserved Populations: Appropriate Use versus Abuse and Diversion" Consensus Meeting in Washington, DC. The country's most renowned experts in the area of pain management and substance abuse reviewed substantial information regarding pain management and substance abuse including the following: --A draft summary paper on pain management and substance abuse that served as briefing material for consensus members; --Annotated bibliographies; --Articles on pain management and substance abuse; and --Key presentations on pain management and substance abuse. 相似文献
7.
A new technique for the quantitative estimation of glycolytic and respiratory enzyme activity in intact and unfixed bone marrow and peripheral blood cells is described. The method gives a two- to three-fold increase in demonstrable enzyme activity per cell compared with existing techniques using fixed marrow film preparations, and is particularly applicable to the study of relatively fragile cells such as the leukaemic lymphoblast. 相似文献
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10.
Debra K. Newton-Nash David Tollerud Lucille Guevarra & Joan C. Gill 《British journal of haematology》1996,95(3):554-560
The outcome of developing immune responses is influenced by interactions among a large and complex network of secreted cytokines. T-cell secretion of interferon-γ (IFN-γ), tumour necrosis factor α (TNF-α) and TNF-β, or lymphotoxin contributes to the development of cell-mediated immunity, whereas secretion of interleukin (IL)-4, IL-5 and IL-6 contributes to development of humoral immunity. Humoral immunity to factor VIII (FVIII) develops in approximately 25% of severe haemophilia A patients. The aim of our research was to understand the underlying immune response to FVIII in patients with FVIII inhibitors. We report a defect in IFN-γ secretion by peripheral blood mononuclear cells (PBMC) derived from haemophilia A patients, which was accompanied by a low level of mitogen-induced proliferation and a significant decrease in the percentage of natural killer (NK) cells. All of the observed defects were found in haemophilia A patients, both with and without FVIII inhibitors, who were free of viral infection and had been treated predominantly or exclusively with monoclonal antibody-purified or recombinant FVIII. 相似文献