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排序方式: 共有424条查询结果,搜索用时 15 毫秒
91.
92.
McDonough SM Liddle SD Hunter R 《针灸推拿医学(英文版)》2009,(5):314-314
Background: Evidence supports the use of exercise for chronic low back pain (CLBP); however, adherence is often poor due to ongoing pain. Auricular acupuncture is a form of pain relief involving the stimulation of points on the outer ear corresponding with specific body parts. It may be a useful adjunct to exercise in managing CLBP; however, there is only limited evidence to support its use with this patient group. Methods/Design: This study was designed to test the feasibility of an assessor-blind randomized controlled trial which assess the effects on clinical outcomes and exercise adherence of adding manual auricular acupuncture to a personalized and supervised exercise programme (PEP) for CLBP. No sample size calculation has been carried out as this study aims to identify CLBP referral rates within the catchment area of the study site. 相似文献
93.
OBJECTIVE: To describe associations among socioeconomic conditions and dietary patterns of Botswana elderly. DESIGN: Secondary analysis from a cross-sectional nationwide survey. PARTICIPANTS: Subjects (N = 1086, 60-99 years old) were selected after multistage sampling. MAIN OUTCOME MEASURES: Dietary patterns were dependent variables; health and socioeconomic variables were independent variables. ANALYSIS: Factor analysis with varimax rotation; least squares regression. RESULTS: The most widely consumed food items were tea (91%), sorghum (82%), and maize-meal (63%). Five dietary patterns emerged: beer; meat/fruit; vegetable/bread; seasonal produce; and milk/tea/candy patterns. Elderly women, those attending church, and those living with grandchildren were less associated with the Beer Pattern. The Vegetable and Bread Pattern was more common among grandparents living with children and those living in towns (urban). Widowed elders were less likely to consume meat/fruit (P < .005). Half had a large family size (6 to 10 children), with about 30% supporting 1 to 5 children. CONCLUSIONS AND IMPLICATIONS: Dietary patterns suggested both food to be emphasized in nutrition education programs and those who may benefit most. Nutrition education efforts in Botswana should focus on improving food diversity, with particular targeting of widowed elderly and those in rural areas, and on increasing vegetable, fruit, meat, and milk intake. 相似文献
94.
A retrospective study of pretransfusion testing records compared the utility of the antiglobulin test (AGT) phase of the crossmatch and the autologous control (autocontrol) for detecting clinically significant alloimmunization to red cells (RBCs). Of 110,780 consecutive crossmatches, 141 were positive after a negative antibody screening test; only 4 of these were due to alloantibodies of potential clinical significance, for a predictive value of a positive AGT crossmatch, after a negative antibody screen, of 2.8 percent (4/141). The frequency of potentially shortened RBC survival was 1 in 27,685 units crossmatched. During a similar period, 56,090 autocontrols were performed with the antibody screen. The autocontrol was positive on 902 samples in which the antibody screen was negative. Antibody identification performed in 684 cases generally yielded only cold or warm autoagglutinins. In 96 cases, some form of alloantibody was detected, but only 25 had potential clinical significance by our criteria. Eight of these alloantibodies had concurrently caused in vivo sensitization of RBCs and were classified as delayed hemolytic transfusion reactions. The predictive value of the autocontrol, calculated as the number of significant alloantibodies detected in autocontrol-positive, antibody-screen-negative samples, was 3.6 percent (25/684). Inspection of these cases revealed 11 in which shortened RBC survival might have resulted if the serologic abnormality had not been detected. Thus, the autocontrol had a slightly greater yield of clinically significant findings than the AGT crossmatch.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
95.
Altered glycosaminoglycan production by HL-60 cells treated with 4- methylumbelliferyl-beta-D-xyloside 总被引:2,自引:0,他引:2
Glycosaminoglycans, mainly chondroitin 4-sulfate, are located in the primary granules of human myeloid cells. These polyanionic carbohydrates are believed to play an important role in leukocyte maturation and function. To study the effect of altered chondroitin sulfate metabolism on human promyelocytic leukemia cells, we have treated HL-60 cells with 4-methylumbelliferyl-beta-D-xyloside. beta-D- Xylosides initiate the synthesis of free chondroitin sulfate chains. Cytochemical studies of treated cells demonstrated a marked increase in cytoplasmic granules stained with cationic dyes. This was confirmed by radiolabeled precursor incorporation studies that demonstrated a 344% increase in 35S-sulfate uptake into glycosaminoglycans associated with the cells and a 39% increase in incorporation into glycosaminoglycans released into the media. Chromatographic analyses of these glycosaminoglycans from treated cells demonstrated that the newly formed chondroitin sulfate chains were not attached to protein core and were of shorter length, but of greater charge density than chondroitin sulfate produced by control cells. Thus, beta-D-xyloside appears to alter the protein linkage, chain length, and sulfation of chondroitin sulfate produced by HL-60 cells, and these changes are morphologically evident. These biochemically altered cells may provide important information concerning the role of these macromolecules in myeloid development. 相似文献
96.
BACKGROUND & AIMS: Infection of epithelial cells with enteropathogenic Escherichia coli (EPEC) induces phosphorylation of the 20-kilodalton myosin light chain (MLC20). The physiological consequence of this biochemical observation, however, has not been discerned. The aim of this study was to determine if EPEC-induced phosphorylation of MLC20 was involved in the associated perturbation of intestinal epithelial barrier function. METHODS: Cultured intestinal epithelial cells, T84, were infected with EPEC. The effects of protein kinase inhibitors on EPEC-induced perturbation of barrier function were assessed using electrophysiological techniques. Alterations in MLC20 phosphorylation were correlated with functional responses. RESULTS: Inhibition of myosin light chain kinase, but not protein kinase C or tyrosine kinase, prevented the decrease in resistance caused by EPEC infection and significantly diminished EPEC-induced MLC20 phosphorylation. Epithelial cell monolayers genetically manipulated to constitutively increase MLC20 phosphorylation were relatively resistant to the effects of EPEC on barrier function. CONCLUSIONS: For the first time, these data show that a physiological consequence of the long-recognized increase in MLC20 phosphorylation by EPEC is perturbation of intestinal epithelial barrier function, which probably contributes to the diarrhea associated with this infection. (Gastroenterology 1997 Dec;113(6):1873-82) 相似文献
97.
98.
Pseudo-von Willebrand disease: a mutation in the platelet glycoprotein Ib alpha gene associated with a hyperactive surface receptor 总被引:4,自引:1,他引:4
Pseudo (platelet-type)-von Willebrand disease is an autosomal dominant bleeding disorder caused by the hyperfunction of a receptor on the platelet surface. The abnormal receptor, glycoprotein Ib, displays increased affinity for its ligand, von Willebrand factor. Four members (normal mother/affected father/two affected daughters) of a family with pseudo-von Willebrand disease were studied to determine the molecular genetic basis for their congenital platelet defect. Segments of the platelet glycoprotein Ib alpha gene were amplified by means of the polymerase chain reaction, cloned, and sequenced. A point mutation (A to G, codon 239) was found in segments from the affected individuals but not from the normal. The mutation results in a single amino acid substitution (valine-mutant for methionine-normal) at residue 239 within the Ib alpha binding site for von Willebrand factor. Both the mutant and the normal sequence were found in affected individuals, suggesting a heterozygous state. Amplified DNA from family members and from 58 normal individuals was analyzed by allele-specific oligonucleotide hybridization. Only the normal sequence was found in the mother and the normal individuals, whereas both the normal and the mutant alleles were found in the affected family members. The described mutation is associated with the pseudo-von Willebrand disease phenotype seen in this kindred. The resultant single amino acid substitution in glycoprotein Ib alpha relates to increased receptor function and to excessive binding of von Willebrand factor to the platelet surface. 相似文献
99.
Todd MB; Waldron JA; Jennings TA; Rome LS; Markowitz SD; Holford TR; Gardner JP; Wolak JP; Malech HL 《Blood》1987,70(1):122-131
In order to determine whether antigenic patterns alter with disease progression and are thereby suggestive of impending blast crisis in chronic myelogenous leukemia, 50 bone marrow biopsy specimens from 32 patients were examined retrospectively using indirect immunoperoxidase labeling with three monoclonal antibodies that detect myeloid antigens. Monoclonal antibodies PMN13F6, PMN7C3, and PMN8C7 detect human neutrophil antigens that first appear at the myeloblast, promyelocyte, and metamyelocyte stages of differentiation, respectively, and persist throughout later differentiation. Percentages of antigen-positive bone marrow cells during the chronic phase were compared with percentages of antigen-positive cells at blast transformation, and time from bone marrow biopsy until blast crisis was correlated with the percentage of bone marrow cells expressing these antigens. Bone marrow biopsy samples from patients in the chronic phase who continue to remain clinically stable 4 to 106 months after biopsy expressed PMN13F6 antigen on 82% +/- 9% (mean +/- SD) of cells, PMN7C3 antigen on 62% +/- 14% of cells, and PMN8C7 on 68% +/- 14% of cells. Bone marrow biopsy specimens obtained from patients 1 or more years prior to blast transformation expressed PMN13F6 antigen on 81% +/- 12%, PMN7C3 antigen on 71% +/- 16%, and PMN8C7 on 64% +/- 16% of cells. Bone marrow biopsy samples obtained between 2 months and 1 year prior to blast crisis expressed PMN13F6 antigen on 68% +/- 15%, PMN7C3 on 51% +/- 17%, and PMN8C7 antigen on 46% +/- 18% of cells. Bone marrow biopsy specimens taken at the time of blast transformation expressed PMN13F6 antigen on 20% +/- 25%, PMN7C3 antigen on 19% +/- 25%, and PMN8C7 antigen on 13% +/- 25% of cells. The difference between the mean of antigen-positive cells from bone marrow biopsy samples obtained at the time of blast crisis was significant compared with the mean of positive cells from biopsy specimens obtained at all other phases of the disease (P less than .001 for all three antibodies). There was a positive correlation between loss of myeloid antigens and disease progression as determined by simple regression of log time and correlation analysis (PMN13F6, r = .6533, P less than .005; PMN7C8, r = .6304, P less than .005; PMN8C7, r = .5215, P less than .05). There was a negative correlation between percentage of immature cells and time to blastic crisis (r = -.6206, P less than .005).(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
100.
The initiation and maintenance of cellular differentiation for a variety of cell types has been shown to be influenced by the microenvironment. To investigate the influence of bone marrow stroma on leukemic cell differentiation, HL-60 human promyelocytic leukemia cells were grown in the presence of Triton-treated extracellular matrix derived from normal human bone marrow stromal cells. This bone marrow matrix microenvironment had a dramatic impact on the phenotypic expression of this malignant line. HL-60 cellular proliferation, morphology, nonspecific esterase activity, formation of Fc rosettes, and sensitivity to induction by 12-O-tetradecanoyl-phorbol-13-acetate (TPA) were all influenced by the presence of matrix molecules. In contrast, stromal cell-conditioned media did not alter HL-60 phenotype. Thus, HL-60 cells appear to retain responsiveness to a human bone marrow stromal cell-derived matrix despite their ability to grow autonomously. Studies of the interaction of leukemic cells and marrow stroma in vitro may provide important information concerning the regulation of leukemic cell behavior. 相似文献