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51.
52.
The leaf essential oil of Eugenia zuchowskiae from Monteverde, Costa Rica, has been obtained by hydrodistillation and analyzed by GC–MS. The principal constituents of E. zuchowskiae leaf oil were α-pinene (28.3%), β-caryophyllene (13.2%), α-humulene (13.1%), and α-copaene (8.1%). The leaf essential oil of E. zuchowskiae showed pronounced in-vitro cytotoxic activity against MCF-7, MDA-MB-468, and UACC-257 human tumor cell lines. The major components showed cytotoxic activities comparable to doxorubicin (LC50 14–70 μg/ml).  相似文献   
53.
Objective. 1. To identify risk factors associated with psychiatric rehospitalization within six months, using global clinical assessments and demographic information and; 2. To determine if risk factors for a hospital in a rural region are similar to those reported for urban hospitals. Method. The setting was a psychiatric unit within a general hospital. All adult admissions for one year were assigned scores on the North Carolina Functional Assessment Scale (NCFAS) and the Global Assessment of Functioning (GAF) scale. Patients were interviewed six months after discharge to determine if they had been rehospitalized and to assign new NCFAS and GAF scores. Results. Significant risk of rehospitalization was predicted by: 1. NCFAS score >90; 2. history of prior hospitalization; 3. nursing home residence; 4. referral from a small community hospital and; 5. non-compliance with outpatient appointments. Conclusions. Global assessments and demographic information collected during an index admission can generate factors to identify patients at risk for rehospitalization within six months. History of prior admissions and non-compliance with outpatient treatment, reported as risk factors in urban settings, were found also to be risk factors in a rural region.He was formerly Assistant Professor, Center for Health Sciences Statistics, East Carolina University School of Medicine.  相似文献   
54.
Human-induced climate change threatens ecosystems and human health on a global scale. In order to withstand the worldwide threats to ecosystems, the concept of sustainable development was introduced during the 1980s. Since then, this concept has been widely applied to guide and focus policy-making. The present article reviews the health consequences of human-induced climate change on sustainable development, particularly the potential impact of such change of food supply, natural disasters, infectious diseases, ecosystems, and sea level rise. Discussed is an integrated model containing the key indicators of sustainable development. The relevance of climate change, human health, and sustainable development for international climate change policy is also examined.  相似文献   
55.
Anti-neutrophil cytoplasmic antibodies (ANCA) are a family of autoantibodies which react with components of phagocytic cells, and are associated with vasculitis and other idiopathic inflammatory disorders. However, the antigenic targets of many of these autoantibodies have not been defined yet. In this study, sodium dodecyl sulphate-polyacrylamide gel electrophoresis (SDS-PAGE) and isoelectric focusing (IEF) were evaluated for characterising the antigenic specificity of unidentified ANCA. The uncharacterised sera included those from patients with ulcerative colitis (n = 21), Crohn's disease (n = 5), cystic fibrosis (n = 16) and sarcoidosis (n = 2). In addition, sera from patients with antibodies to the phagocytic enzymes proteinase 3 (PR3) (n = 11) and myeloperoxidase (MPO) (n = 5) were also included. The sub-cellular localisation of antigens was determined by testing sera against crude neutrophil extract and sub-cellular fractions consisting of azurophilic granules, specific granules and cytosolic, fractions using enzyme-linked immunosorbent assays (ELISAs). All sera reacted with the crude and azurophilic granule extracts. The native system of IEF followed by capillary immunoblotting successfully detected anti-PR3 and anti-MPO in azurophilic granule extracts. In contrast, SDS-PAGE Western blotting failed to detect any reactivity, either to PR3 or MPO, in the crude extract or azurophilic granule extract. However, the antibody specificity of patient sera with uncharacterised autoantibodies could not be detected by IEF/capillary immunoblotting or SDS-PAGE. This study showed that the sub-cellular azurophilic granules are the antigenic target of a variety of uncharacterised ANCA. It also showed that IEF characterised both anti-PR3 and anti-MPO but failed to detect other forms of ANCA. In contrast, the majority of common ANCA were not detected by SDS-PAGE.  相似文献   
56.
We compared data from 243 patients with episodic migraine (EM) and 132 patients with chronic daily headache (CDH). We divided the matter group into those with tension-type headache only (CDH Type 1) and those with headaches having migrainous features (CDH Types 2+3) and compared each with the EM group and all three groups with one another. CDH Type l patients differed from those in the other groups by virtue of gender (more often male) and mean age at headache onset (older). The CDH Types 2+3 and EM groups differed only in that the former were more likely to have undergone a brain-imaging study. These data suggest that CDH Type 1 may represent a distinct headache syndrome, while CDH Types 2+3 closely resemble episodic migraine.  相似文献   
57.
Low-income minority patients from East St. Louis, Illinois, a depressed midwestern urban city, who had visited acute care settings with asthma symptoms, participated in a focus group. Questions were constructed around the Health Belief Model to characterize participants' experiences in receiving asthma care, their confidence in long-term asthma self-management, barriers they perceived to managing their asthma, and recommendations they would make for improving asthma care in their community. Analysis of comments suggests an appreciable understanding of asthma triggers, limited coping behaviors for asthma symptoms, very limited practice of active asthma management, perception of the health care system as frequently insensitive to their needs or their knowledge of their own care, exchange of well-articulated information regarding how to deal with the system, and an apparent lack of awareness of any potential contribution of patient education or support system.  相似文献   
58.
The effect of aluminum on the metabolism of glutamate and glutamine in astrocytes was studied to provide information about a possible biochemical mechanism for aluminum neurotoxicity and its potential contribution to neurodegenerative disease. Exposure of cultured rat brain astrocytes for 3–4 d to 5–7.5 mM aluminum lactate increased glutamine synthetase activity by 100–300% and diminished glutaminase activity by 50–85%. Increased glutamine synthetase enzyme activity was accompanied by an elevated level of glutamine synthetase mRNA. Alterations in glutaminase and glutamine synthetase following aluminum exposure caused increased intracellular glutamine levels, decreased intracellular glutamate levels, and increased conversion of glutamate to glutamine and the release of the latter into the extracellular space. The results of these changes may alter the availability of neurotransmitter glutamate in vivo and may be a mechanism for the aluminum neurotoxicity observed in individuals exposed to the metal during dialysis procedures and other situations.  相似文献   
59.
Prognostic significance of serum cholesterol in nursing home men   总被引:2,自引:0,他引:2  
Serum cholesterol was measured in 129 men (average age 70.6; range 41-96) of a Veterans Administration Nursing Home, and was correlated with other items in an extensive clinical data base. Serum cholesterol was less than 150 mg/dl in 13% of the subjects, and was less than 160 mg/dl in 18%. Cholesterol greater than 280 mg/dl occurred in 8%. Serum cholesterol varied directly (p less than 0.02) with: body weight, serum albumin, serum total protein, serum sodium, ability to walk, and ability to feed oneself; and indirectly (p less than 0.02) with death rate, degree of functional dependence, and serum SGOT and LDH. Nursing home men with cholesterol less than 150 mg/dl had a death rate of 63% during the 14 months after the cholesterol analysis, compared to a death rate of 9% in men with cholesterol greater than 150 mg/dl (p less than 0.05). Death rate during the year after the analysis was 52% if cholesterol was below 160 mg/dl, compared to 7% if it was above this threshold (p less than 0.05).  相似文献   
60.
A comparative study of three subgroups of meniscal transplants was undertaken in the goat model: Group 1 (autograft) involved removal and immediate reimplantation of the meniscus; Group 2, fresh meniscal allografts; and Group 3, cryopreserved (30 days) meniscal allografts. Six months after surgery, tissues were evaluated for gross degenerative changes, proteoglycan concentration (as assessed by uronic acid), water content, vascularity, histology, and cell viability. The contralateral knee served as control for all comparisons. There was no statistical difference in the amount of arthritis present and all transplants demonstrated an essentially normal peripheral vascularity compared to controls. Sections revealed reduced numbers of cells in the central portions of the transplanted menisci and these viable cells demonstrated different behavior in multiplication in tissue culture compared to contralateral controls. Grossly and microscopically, the implanted menisci differed little from the controls. The measurement of proteoglycan concentration and water content of the transplanted meniscal cartilage suggest alterations that may affect the long-term mechanical properties. The autograft specimens showed the water content was very slightly increased (3% to 6%), while the proteoglycan concentration was increased (42% in terms of uronic acid). In contrast, the water content of the fresh allograft group and the cryopreserved group was increased 12% to 24%. Proteoglycan concentration in these groups was decreased up to 56% in portions of some menisci compared to controls. Fresh and cryopreserved meniscal allografts showed peripheral healing, revascularization, cellularity, and incorporation, and grossly appeared good at 6 months in the goat model. The biochemical changes in the extracellular matrix at 6 months raises questions on the long-term function of these transplanted menisci.  相似文献   
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