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61.
不同肝病患者外周血CD25+细胞检测的临床意义   总被引:2,自引:0,他引:2  
目的 探讨外周血CD25+细胞含量与肝病患者病情转化及预后的关系。方法 采用流式细胞术对155例肝病患者及50名正常人外周血CD25+细胞进行检测,并对68例治疗好转患者进行治疗前后比较。结果 各种肝病患者外周血CD25+细胞含量明显低于正常对照组(均P〈0.01),其下降程度依次为肝癌患者〉肝炎后肝硬化患者〉慢性活动性肝炎和慢性迁延性肝炎患者。68例肝病患者治疗后CD25+细胞含量较治疗前明显升  相似文献   
62.
Based on the fact that chemical products such as binding agents are produced by mixing three kinds of phosphates with different ratios, we mixed metaphosphate, polyphosphate and pyrophosphate. Each was made to Na-phosphate, K-phosphate, and Ca-phosphate and each was mixed with commercial feeds so that the content of P would be approximately 0.1, 0.15, 0.3, 0.4, 0.6 and 1.0%. The prepared pellets were given to ICR, CF # 1 and AKR strains of mice at 29 days of age for 680 days and observations were made through this experimental period at different stages. The observations were also carried out on the mice administered with the experimental feeds for 1.5 months from 9 to 10.5 months of age. The observations were compared with those of the control group at all times. As a result, plasma 1 α, 25 (OH)2 D3 and P levels were always significantly higher in the phosphate administered groups relative to the control. Urine P and Fe increased while urine Ca decreased in the phosphate-treated groups. The effect of phosphates on the bones was studied taking soft X-ray pictures of hind legs and applying microdensitometry to them. Through these observations we recognized thinning of the cortex of bones, reduction of marrow trabecules and development of osteophyte. Histological observations disclosed that changes in knee joint tissues were apparent; that is, a decrease in or an irregular loss of the number of cells in superficial, intermediate, and radial strata of the joint cartilage, proliferation of subchondral bone, and the development of osteophytes were noted. As for muscles, diameters of musclar fibers became smaller; in particular, type II fibers showed greater shrinkage. Regarding kidneys, swelling and atrophy of glomerular capillaries, proliferation of mesangial cells, nephroselerosis, swelling, thinning, and loss of tubular epithelium, interstitial tissue inflammation, development of cylindruria, and deposition of calcium were observed. All these changes seem to be a particularly advanced aspect of the changes which are more pronounced with increasing dose and age. These changes were found even in the group administered with the feed containing 0.1% phosphorus, and, these changes were dependent on the concentration level of P. It was observed that administration to older subjects for a short term (1.5 months) produced effects stronger than those to younger subjects administered for a long term (10.5 months). The effects of condensed Ca-phosphate on bones were similar to those of condensed Na- and K-phosphates, and, hence, it was supposed that these effects were caused by phosphate radicals. An erratum to this article is available at .  相似文献   
63.
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   
64.
Epidemiologic and experimental data support a role for 1,25-dihydroxyvitamin D3 in the growth regulation of prostate cancer. We conducted a phase II clinical trial evaluating calcitriol (1,25(OH)2D3) in patients with hormone refractory prostate cancer. We enrolled 14 patients in this study. 1,25(OH)2D3 was initiated at a daily oral dose of 0.5 μg and escalated to 1.5 μg daily. No objective responses were observed. However, in two patients decreases of 25% and 45% in prostate specific antigen levels were seen. Hypercalcemia was the predominant toxicity. We conclude that 1,25(OH)2D3 given in this manner is inactive in advanced prostate cancer. Dose escalation of oral 1,25(OH)2D3 is limited by hypercalcemia.  相似文献   
65.
探讨婴幼儿维生素D缺乏性佝偻病的早期诊断。方法应用微量末稍血测定血清25-(OH)D3和相关指标,对248名0-3岁儿童进行调查。结果25-(OH)D3、ALP、ALP3无性别差异,在每半年一个龄龄组分组中,以0-6月龄组婴幼儿的25-(OH)D3最低,而ALP、ALP明显升高。  相似文献   
66.
通过磷酸钙沉淀法将载体DNA转染Caco-2细胞。Caeo-2细胞经不同浓度1,25一二羟维生素D3处理后,测定表达的荧光素酶活性。结果;当pSG5-VDR表达载体共转染时1,25一二羟维生素D3显著地抑制Caco-2细胞荧光素酶的表达;而未使用pSG5-VDR表达载体共转染时,则无抑制作用。说明1,25一二羟维生素D3能抑制报导载体pGL2荧光素酶的表达。类似于人类PTH基因中的潜在抑制性VDRE存在于报导载体pGL2。  相似文献   
67.
Cytokines predict coronary aneurysm formation in Kawasaki disease patients   总被引:5,自引:0,他引:5  
In this study, we measured serially the serum levels of cytokines including interleukin-6 (IL-6), IL-8, soluble IL-2 receptor (sIL-2R) and tumour necrosis factor (TNF-) in 60 patients with Kawasaki disease (KD) and evaluated the clinical significance of these cytokines in predicting coronary aneurysm formation. Of the 60 patients, 12 were complicated with coronary aneurysm. Blood samples were collected within the 1st week after onset of fever, then once a week for the 1st month, and once a month for another 5 months. The serum levels of IL-6, IL-8, sIL-2R and TNF were measured using an ELISA or RIA method. Our results show that the changes in serum IL-6 and IL-8 were faster than those of sIL-2R and TNF. Within the 1st week, the serum levels of IL-6 and IL-8 were significantly higher in the patients with than in those without coronary aneurysm (P<0.001). In addition, the serum levels of IL-6 and IL-8 obtained in the 1st week were highly correlated (P<0.001) with those of C-reactive protein and erythrocyte sedimentation rate, and the serum levels of sIL-2R and TNF were also increased at the 1st week reaching the highest level in the 2nd week. In the 2nd week, the serum levels of sIL-2R and TNF were significantly higher in the patients with than in those without coronary aneurysm (P<0.05). These findings suggest that the serum levels of IL-6 and IL-8 obtained in the 1st week may serve as useful parameters in predicting coronary aneurysm formation in KD patients.  相似文献   
68.
In the human hair follicle, outer root sheath (ORS) cells constitutively express the hyperproliferation-associated keratins 6, 16 and 17 instead of keratins 1 and 10 found in interfollicular epidermis. In organotypic cultures, ORS cells form a stratified epithelium which in many respects resembles psoriatic skin: it has a hyperplastic tissue architecture and a poorly developed granular layer, and expresses hyperproliferation-associated keratins. Therefore, we studied the effects of the antipsoriatic compounds 1,25-dihydroxy-vitamin D3 (1,25-(OH)2-D3) and its synthetic derivative calcipotriol on cultured ORS cells. In monolayer cultures, 10–6 M 1,25-(OH)2-D3 or calcipotriol completely blocked ORS cell proliferation. This inhibitory effect was substantially reduced at 10–8 M. Incubation of organotypic ORS cultures with both vitamin D analogues resulted in a marked thinning of the living cell compartment concomitant with a thickening of the horny layer. A reduced expression of differentiation markers such as keratins 10,16 and 17, involucrin and filaggrin paralleled the thinning of the stratum Malpighi. As determined by quantification of BrdU-positive cells, ORS cell proliferation was apparently not affected by the vitamin D analogues, indicating that these compounds mainly operate by accelerating the differentiation pathway within the suprabasal living cell compartment. No alteration in the expression of the 6- and 1-integrin chains was found.  相似文献   
69.
The oral administration for 5 days of excess 1,25-dihydroxychole-calciferol [1,25(OH)2D3] at doses of 1, 5, and 25 g/kg to rats, beginning at the age of 2 or 10 days, produced dose-dependent reductions in weight development and additional calcification near the skeleton. Alizarin red S stained skeleton revealed calcific deposits near the bones of the head, near the neural arches, between the ribs, along the bones both of the fore limbs and, to a lesser extent, of the hind limbs.Historically, the deposits appeared to be localized primarily in the subepithelial connective tissues. Starting treatment with 1,25(OH)2D3 (25 g/kg for 5 days) at the age of 20 days produced additional calcification in 1 of 8 rats at only 1 location (lower jaw). Additional calcification as described above could no longer be induced by 1,25(OH)2D3 in 30-day-old rats using doses up to 25 g/kg and 10 daily treatments. We conclude that the sensitivity of young rats to 1,25(OH)2D3-induced additional calcification, which differs in localization from that observed in adult rats, decreases with the maturation of the animals.  相似文献   
70.
Midgut volvulus with extensive intestinal necrosis in the newborn period and in early infancy and childhood presents a difficult therapeutic dilemma of how to control sepsis and preserve a maximum and life-sustaining amount of large and small intestine. This problem is similar to that faced in cases of necrotizing enterocolitis with extensive intestinal ischemia and necrosis. The successful use of the patch, drain, and wait approach in necrotizing enterocolitis suggested its potential usefulness in midgut volvulus with similarly extensive necrosis in early life [7]. The basic principles of this approach involve maximum bowel salvage by avoidance of both resection and enterostomy; extensive bilateral Penrose drainage of the peritoneal cavity to provide an exit for sepsis and debris for peritonitis control; and de facto enterostomies for potential enteric fistula capture, gastrostomy for upper gastrointestinal tract venting and decompression, and Broviac catheter placement for long-term hyperalimentation. Three cases involving the successful use of this approach are reported.  相似文献   
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