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91.
Khai Lai Monica Rencken Barbara L. Drinkwater Charles H. Chesnut III 《Calcified tissue international》1993,53(4):225-228
Summary The purpose of this study was to determine whether bone mineral density (BMD) measurements at the lumbar spine and femoral neck provided comparable information to women planning to use that knowledge to help them make a decision about hormone replacement therapy. Eighty-eight healthy Caucasian women, aged 44–59 and within 0 to 5 years of menopause, participated in the study. BMD measurements were performed at the lumbar spine (L1-L4) and the femoral neck by dual energy X-ray absorptiometry (DXA). Criteria suggested by the National Osteoporosis Foundation were used to categorize women as at risk for osteoporosis, bone density more than one standard deviation (SD) below the young adult mean, or as low risk, bone density at or above this level. The re that 46 women would be classified into the low risk category on the basis of spinal BMD alone. However, 28 of these 46 women would fall into the at risk category when the femoral neck BMD was measured. Sixty-one percent of women informed they were at low risk on the basis of spinal BMD would be considered at risk based on femoral neck BMD. When femoral neck BMD was used as the primary risk indicator, 14% of the women classified as low risk would be at risk if spinal BMD were added. These results suggest that both lumbar spine and proximal femur measurements should be made when women are using bone density measurements as an aid in deciding whether or not to use hormone therapy in their postmenopausal years. 相似文献
92.
R Sorcinelli A Sitzia A Figus M E Lai 《Metabolic, pediatric, and systemic ophthalmology (New York, N.Y. : 1985)》1990,13(1):23-25
Eye examination was performed in a series of 53 patients whose mean age was 19.5 years (range from 11 to 25 years), affected from Cooley's disease, in treatment with transfusions and desferrioxamine in subcutaneous infusion. The most frequent ocular change was fundus mottling appearance like "leopard skin" (15%). We found also lens opacity (11%), drusen (7%), retinal venous tortuosity (5%), without impairment of visual acuity. The pathogenic factors of the ocular change are related to abnormality of iron metabolism. These results suggest that the involvement of desferrioxamine to remove iron from the eyeball is relatively small. 相似文献
93.
毫米波辐射对白血病细胞的细胞结构、自由基和bcl-2基因表达的影响 总被引:2,自引:0,他引:2
目的 研究毫米波辐射对白血病细胞株的细胞结构、培养体系中的氧化自由基和抗氧化酶系,以及bcl-2基因表达的影响。方法 电镜显微技术研究细胞结构的变化,AnnexinV/PI双染法结合流式细胞术分析细胞株凋亡和坏死,硫代巴比妥酸(TBA)法和邻苯三酚法测定细胞株培养体系中的脂质过氧化物(LPO)和超氧化物歧化酶(SOD)的含量变化;流式细胞仪结合荧光标记抗体检测bcl-2基因表达。结果 毫米波辐射使白血病细胞株细胞结构产生显著的退行性变化,显著诱导细胞凋亡和坏死,抑制细胞活力,脂质过氧化物含量上升,SOD含量下降,bcl-2基因的表达显著下降。结论 毫米波辐射有明显的诱导白血病细胞凋亡的效应,其机制与辐射后氧化自由基水平上升、抗氧化酶系活性下降及bcl-2基因的表达下降有关。 相似文献
94.
切应力作用下联合培养的血管内皮细胞血管假性血友病因子的含量变化 总被引:2,自引:0,他引:2
目的:研究切应力对与血管平滑肌细胞联合培养的内皮细胞的抗凝血和粘附的影响。方法:对与平滑肌细胞联合培养的内皮细胞施加生理范围的切应力,用免疫组化及图像分析法检测内皮细胞的血管假性血友病因子(vWF)含量。结果:联合培养的内皮细胞vWF的变化与切应力大小及作用时间有关,随切应力增大,胞内vWF含量逐渐减少,且切应力作用的第1小时减少的最快。结论:生理范围的切应力作用,可能减少与平滑肌细胞联合培养的内皮细胞的vWF表达,或促使vWF短时释放加快,有利于增强抗凝血功能及内皮细胞的粘附。 相似文献
95.
96.
天麻丸中天麻的显微定量研究 总被引:2,自引:0,他引:2
目的 :制定天麻在天麻丸中的显微定量标准。方法 :用显微定量法 ,以天麻的木化厚壁细胞为显微特征物 ,对天麻丸中的天麻进行测定。结果 :天麻含量与每mg特征数呈显著的线性正相关。回归方程为 y =6 2 35x 1 80× 10 -3 (γ =0 9999,a =0 0 5 )。结论 :显微定量法测定天麻丸中天麻的含量是可行的 ,结果可靠。 相似文献
97.
Savaraj N Xu R Landy H Lai S Sternau L Solomon J Wu C Lampidis T Feun L 《Oncology reports》1997,4(4):857-861
Topoisomerase I (TOP I) and II (TOP II) activities and their corresponding levels were analyzed in 27 primary brain tumors and 32 lung cancers (28 NSCLC, 4 SCLC). The TOP I and II activities in primary brain tumors varied from 500-2,000 units/mg and 100-3,000 units/mg respectively. Their corresponding levels varied from <0.01-3.30 (TOP I) and 0.24-8.30 (TOP II) arbitrary units. In lung cancer, the TOP I and II activities ranged from 1,000-4,000 and 500-4,000 units/mg respectively with their levels ranging from 0.30-61.60 and 0.2-14.2 arbitrary units respectively. These parameters were compared in both tumors using the Wilcoxon rank sums test, the difference were statically significance for all four parameters with a p<0.0001 for TOP I and II activities and TOP I levels and p<0.09 for TOP II levels. Using linear regression analysis, there was no correlation between TOP I and II activities and their corresponding levels in primary brain tumor. However, in lung cancer, the relationship between TOP I activities and levels were linear with r(2)=0.2 and p<0.0094, but not for TOP II activity and their levels. There was no relationship between TOP I and TOP II levels in the same tumor for both types of cancer. The future clinical implication of these findings are discussed. 相似文献
98.
Nishio M Xu L Sasaki M Haga S Okumoto M Mori N Sarkar NH Acha-Orbea H Enami J Imai S 《Breast cancer (Tokyo, Japan)》1994,1(2):89-94
Mammary tumors of a newly isolated strain of Chinese wild mouse (JYG mouse) harbor exogenous mouse mammary tumor virus (MMTV). The complete nucleotide sequence of exogenous JYG-MMTV was determined on the proviral 5' long terminal repeat (LTR)(partial)-gag-pol-env-3' LTR (partial) fragment cloned into a plasmid vector and the cDNA sequence from JYG-MMTV producing cells. Similarly to the other MMTV species the LTR of JYG-MMTV contains an open reading frame (ORF). The amino acid sequence of the JYG-MMTV ORF resembles that of SW-MMTV (92% identity) and endogenous Mtv-7 (93% identity) especially at the C-terminal region. Thus, a functional similarity in T-cell receptor V beta recognition as a superantigen is implicated among these MMTV species. Analysis of the viral gag nucleotide sequence revealed that this gene is not disrupted by the bacterial insertion sequence IS1 or IS2, which have been reported to be present in the majority of the plasmids containing the gag region. Comparison of amino acid sequences of JYG-MMTV with those of BR6-MMTV showed that over 96% of the amino acids of gag, pol, protease and env products are identical. These results suggest the intact nature of the nucleotide sequence of the near full-length MMTV genome cloned in the plasmid. 相似文献
99.
G. Mantovani A. Macciò R. Versace M. Pisano P. Lai S. Esu M. Ghiani D. Dessì E. Turnu M. C. Santona R. Cherchi G. S. Del Giacco 《Journal of molecular medicine (Berlin, Germany)》1995,73(8):409-416
This work was designed to study the proliferative response of tumor-associated lymphocytes (TAL) from neoplastic effusions against autologous tumor cells and the immunophenotype pattern of TAL from neoplastic effusions and that of PBMC of the same patients. We also compared the serum levels of the cytokines interleukin (IL) 1, 2 and 6, tumor necrosis factor- (TNF) and soluble IL-2 receptor (sIL-2R) with those present in neoplastic effusions of the same patients. Moreover, we examined the ability of TAL and peripheral blood mononuclear cells (PBMC) to produce and release the cytokines and sIL-2R and to express membrane CD25 following their stimulation with phytohemagglutinin (PHA) in vitro. Finally, we compared the cytokines/sIL-2R production and membrane CD25 expression by PHA-stimulated PBMC of the patients with neoplastic effusions with a series of 90 cancer patients without neoplastic effusions and 20 normal healthy subjects. Thirteen neoplastic pleural and eight peritoneal effusions were collected from 11 patients with primary lung cancer, 7 with primary epithelial ovarian cancer, 1 with breast cancer, 1 with pleural mesothelioma, and 1 with pancreatic cancer. The proliferative response of TAL from neoplastic effusions against autologous tumor cells was lower than the response to PHA, IL-2, and anti-CD3, but significant. The percentage distribution of CD3+ and CD8+ lymphocyte subpopulations was higher in peritoneal than in pleural effusions, while the CD16+ subset was higher in pleural than in peritoneal effusions. The percentage distribution of CD16+ was significantly lower in pleural effusions than in PBMC of patients with pleural effusions. The CD39 antigen was higher on TAL from peritoneal effusions than on PBMC of the same patients. The levels of IL-1 and sIL-2R in peritoneal effusions did not differ from those measured in the sera of the same patients, while the levels of IL-2, IL-6, and TNF were higher in the peritoneal effusions. The levels of IL-2, IL-6, TNF, and sIL-2R, but not IL-1, in pleural effusions were significantly higher than those found in the sera of the same patients. The amounts of IL-2 and IL-6 produced by TAL were generally higher than those released by PBMC. The secretion of cytokines IL-1, IL-2, and sIL2R by PHA-stimulated PBMC was lower, but IL-1 and IL-6 secretion was higher in cancer patients with neoplastic effusions than in either cancer patients without neoplastic effusions or normal subjects. The CD25 expression on PHA-stimulated PBMC derived from cancer patients with neoplastic effusions was in the same range as that of cancer patients without neoplastic effusions and normal subjects. These findings suggest that TAL may be able to produce cytokines and may be amenable to immune manipulation.Abbreviations
FITC
Fluorescein-isothiocyanate
-
IL
Interleukin
-
mAb
Monoclonal antibody
-
MHC
Major histocompatibility complex
-
NK
Natural killer
-
PBMC
Peripheral blood mononuclear cells
-
PHA
Phytohemagglutinin
-
TAL
Tumor-associated lymphocytes
-
TIL
Tumor-infiltrating lymphocytes
-
TNF
Tumor necrosis factor-
-
sIL-2R
Soluble interleukin-2 receptor 相似文献
100.
Quartu M Lai ML Del Fiacco M 《Italian journal of anatomy and embryology = Archivio italiano di anatomia ed embriologia》1995,100(Z1):205-211
By means of immunohistochemistry the presence of the growth-associated protein GAP-43 and its codistribution with substance P (SP) and calcitonin gene-related peptide (CGRP) are studied in the human spinal trigeminal, gracile, and cuneate nuclei at perinatal and adult life stages. The results obtained show that the distribution pattern of GAP-43 in the areas examined varies with age and that the immunohistochemical detectability of the protein persists in discrete subregions of the trigeminal and cuneate nuclei of the adult, where its localization closely matches that of SP and CGRP. It is suggested that neuronal plasticity may be pronounced throughout life in areas of the human nervous system involved in the neurotransmission of protopathic stimuli at the first synaptic level. Discrete subregions of the cuneate nucleus, bearing neurochemical characteristics strikingly similar to those of the substantia gelatinosa of the trigeminal subnucleus caudalis are pointed out. 相似文献