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1.
Adjuvant immunotherapy with interferons and/or interleukin 2 (IL-2) is widely used for advanced kidney cancer. However, the results are not satisfactory so far. The purpose of this study is to evaluate the inducible activity of lymphokine-activated killer (LAK) cells against autologous human renal cell carcinoma. The effect of interleukin 7 (IL-7) on IL-2-induced LAK activity was assessed by the autologous assay system which we have established. Peripheral blood lymphocytes from patients with renal cell carcinoma were stimulated with IL-2 and/or IL-7, and tested for antitumor activity against autologous renal cell carcinoma. In all 10 cases tested, IL-7 alone induced LAK activity. Moreover, IL-2-induced LAK activity was augmented by the concomitant addition of IL-7. Flow cytometry revealed an increase in IL-2-receptor-positive lymphocytes following incubation with IL-7. These results suggest that combination therapy using IL-2 and IL-7 may be a useful treatment for patients with advanced renal cell carcinoma.  相似文献   

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We studied the mortality in three villages in the Cappadocian region of Central Anatolia, Karain, Tuzk?y, and Sarihidir, which were exposed to fibrous zeolite (erionite), a known carcinogen more potent than the amphibole asbestos. Between 1970 and 1994, there were 305 deaths in Karain, and 177 (58%) were cancer related, including 150 (49.2%) malignant pleural mesothelioma, seven (2.3%) malignant peritoneal mesothelioma, and six (1%) gastroesophageal carcinoma. Four deaths (1.3%) from lung cancer included two nonsmoking females. There were three cases (1%) of leukemia and six of other malignancies (1.9%). Between 1980 and 1994, there were 519 deaths in Tuzk?y (T) and Sarihidir (S) (T = 432, S = 87). Of these, 257 were cancer related, and included 120 cases of malignant pleural mesothelioma and 64 cases of malignant peritoneal mesothelioma. Intraabdominal carcinoma was noted in 29 patients and 14 patients had lung cancer (four of whom were nonsmoking women). There were five cases of gastroesophageal cancer, five deaths due to leukemia, and 16 cases of various malignancies. These mortality figures support the hypothesis that erionite fibers cause cancer other than mesothelioma and lung cancer. Mineralogic analyses of the tissues should be performed to demonstrate this relationship.  相似文献   

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Membrane filters with pore-size ratings of 0.22 microns and 0.45 microns were tested for their ability to recover Pseudomonas diminuta ATCC 19146 (P. diminuta), the organism typically used in bacterial retention testing of sterilizing-grade membrane filters. For each of the two pore-size ratings, filters of two membrane filter polymer materials, hydrophilic PVDF (Millipore Durapore) and mixed esters of cellulose, were tested, resulting in an evaluation of four potential recovery filters. The 0.45 microns mixed esters of cellulose filter is the currently accepted membrane for this purpose. The data show no difference in the ability of the four filters to recover freshly cultured P. diminuta. Moreover, the membrane-filter method was shown to provide a very high bacterial-recovery efficiency, equivalent to that of the spread-plate method. Thus, 0.22 micron filters, despite their ability to retain higher levels of bacteria, proved not to have an advantage over 0.45 micron membranes in terms of bacterial recovery. This result, combined with (1) the knowledge that more open membranes have been shown experimentally to more efficiently recover stressed organisms; (2) the potential to produce stressed cells in an actual bacterial retention test; and (3) the long history of the successful use of 0.45 microns mixed esters of cellulose for bacterial recovery, support the continued use of the 0.45 micron filter in this application.  相似文献   

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Isoform-specific effects of apolipoprotein E (apoE) on neurite outgrowth and the cytoskeleton are associated with higher intracellular levels of apoE3 than apoE4 in cultured neurons. The current studies, designed to determine the mechanism for the differential intracellular accumulation or retention of apoE, demonstrate that apoE3- and apoE4-containing beta-very low density lipoproteins (beta-VLDL) possess similar cell binding and internalization and delivery of cholesterol to the cells. However, as assessed by immunocytochemistry, analysis of extracted cellular proteins, or quantitation of 125I-apoE-enriched beta-VLDL, there was a 2-3-fold greater accumulation of apoE3 than apoE4 in Neuro-2a cells, fibroblasts, and hepatocytes (HepG2) after 1-2 h, and this differential was maintained for up to 48 h. ApoE2 also accumulated in Neuro-2a cells to a greater extent than apoE4. The differential effect was mediated by the apoE-enriched beta-VLDL and not by free apoE. Neither the low density lipoprotein receptor nor the low density lipoprotein receptor-related protein was responsible for the differential accumulation of apoE3 and apoE4, since cells deficient in either or both of these receptors also displayed the differential accumulation. The effect appears to be mediated primarily by cell surface heparan sulfate proteoglycans (HSPG). The retention of both apoE3 and apoE4 was markedly reduced, and the differential accumulation of apoE3 and apoE4 was eliminated both in mutant Chinese hamster ovary cells that did not express HSPG and in HSPG-expressing cells treated with heparinase. The data suggest that cell surface HSPG directly mediate the uptake of apoE-containing lipoproteins, that the differential accumulation/retention of apoE by cells is mediated via HSPG, and that there is a differential intracellular handling of the specific apoE isoforms.  相似文献   

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Myocarditis and progression to cardiomyopathy is associated with focal spasm and reperfusion of the coronary microcirculation. Experimental autoimmune myocarditis (EAM), induced with cardiomyosin peptide-specific T cells in Lewis rats, was hypothesized to cause acute hemodynamic and coronary vasculature changes. Fifteen experimental animals (5 each at 1, 2, and 3 weeks after T-cell injection) and eight controls were studied using the constant pressure variant of the isolated heart. Coronary resistant decreased while coronary flow increased (P < 0.05) in EAM hearts after the first week. Rate-pressure product, +dP/dt and -dP/dt, decreased while the heart/body weight ratio increased (P < 0.05) compared with controls at 1 week but not at 2 or 3 weeks. Mean local myocardial PO2, which reflects local oxygen delivery and consumption, and MVO2 were not different for EAM hearts. However, compared with controls EAM myocardial PO2 varied more widely and was often beyond the usual range, suggesting the occurrence of localized hypoxic and hyperoxic areas. In summary, after the first week there was a significant decrease in coronary resistance in the EAM animals, which required higher flow to maintain a similar perfusion pressure. These changes in coronary resistance and flow along with the heterogeneity and extremes of local myocardial PO2 levels without a significant change in MVO2 may be explained by postulating development of low-resistance, high-flow hyperoxic areas which steal flow, thus causing hypoxia in other areas.  相似文献   

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MDL 74,721 (R)-2-(N1,N1-dipropylamino)-8-methylaminosulfonylmethyl-1,2,3,4-te trahydronaphthalene, a sulfonamidotetralin, has been found to exhibit a 10,000-fold greater potency in neurogenic versus vascular models of migraine. Sumatriptan, a relatively pure 5-HT1D/5-HT1B receptor agonist, also showed higher potency versus neurogenic inflammation. However, for sumatriptan the potency difference (100-fold) in the two pathophysiological models was less pronounced than seen for MDL 74,721. The affinity profile of MDL 74,721 at 5-HT1 receptor subtypes may in part explain its ability to differentiate these two physiological responses. MDL 74,721 demonstrated nanomolar affinity for 5-HT1A (12.7 +/- 0.3 nM) and 5-HT1D (41.3 +/- 10.9 nM) but considerably lower affinity for 5-HT1B receptors (> 1000 nM). Serotonin-like activity was seen in in vitro functional assays including inhibition of forskolin-stimulated cAMP accumulation in human 5-HT1D receptor-transfected fibroblasts or eliciting vasoconstriction in isolated human pial arteries. The intrinsic activity (relative to 5 - HT[E(Amax)]) and affinity (pD2) for the human cerebrovascular 5-HT receptors were: 5-HT (100%, 7.51 +/- 0.09), sumatriptan (94%, 6.85 +/- 0.1) and MDL 74,721 (66%, 5.70 +/- 0.23). In anaesthetised cats, treatment with MDL 74,721 resulted in a dose-related reduction in the percentage of carotid flow going through the arteriovenous anastomoses to the lungs, with an ED50 of 0.3 mg/kg i.v., the same as sumatriptan. However, in the guinea-pig neurogenic model, MDL 74,721 inhibited plasma protein extravasation with an ED50 of 0.023 microg/kg compared to 2.5 microg/kg for sumatriptan. MDL 74,721 was also effective in this model (in rats) after oral administration. In conclusion, MDL 74,721 demonstrates a preclinical profile consistent with anti-migraine efficacy. Its marked preference for inhibiting neurogenic inflammation makes this compound a useful tool for assessing the relative contribution of this pathophysiological mechanism to the human disease state.  相似文献   

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粒径≤2μm的超细粉体颗粒分散方式探讨   总被引:5,自引:0,他引:5  
超细粉体随其颗粒粒度减小,自发团聚趋势更加明显.改善粉体的分散性是实现超细粉体分级的前提,也是实现工业化应用的关键.论文作者探讨了粉体团聚和分散的作用机理,分析、比较了超细粉体在空气中和液相中的分散方法及适用范围,认为对于粒径≤2 μm的超细粉体,因颗粒间的范德华引力比重力大几百倍,因而不会因重力而分离,只宜采用在液相中分散的方法使之分散,其分散途径有:通过改变分散相与分散介质的性质来调控HAMAKER常数,使其值变小,颗粒间吸引力下降;调节电解质及定位离子的浓度,促使双电层厚度增加,增大颗粒间的排斥力;选用与分散颗粒和分散介质均具有较强亲和力的聚合物电解质,通过空间位阻和静电协同作用来达到优异的分散效果.  相似文献   

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选用SE-30大口径毛细管色谱柱和氢火焰离子化检测器(FID),使用N2000色谱工作站,采用峰面积归一法,建立了气相色谱分析乙硫氨酯的方法。当乙硫氨酯的体积分数为95%~98%时,采用该方法与《YS/T 357—1994乙硫氨酯的技术条件》中硝酸汞滴定法的分析结果进行比较,相对标准偏差为0.04%~0.06%。该气相色谱分析方法适用于以异丙基黄药、氯乙酸、纯碱和一乙胺为原料而合成的乙硫氨酯分析。  相似文献   

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Exogenous and indigenous cases of zoonotic cutaneous leishmaniasis are reported in several Egyptian Governorates particularly those in the Nile Delta, Phlebotomus paptasi (Scopoli) is the only proven insect vector. This paper was intended to study the seasonal abundance, nocturnal activity and breeding sites as well as other relevant behaviour aiming to throw some light on this insect vector. The results showed that: (a) the seasonal activity started in April and ended in November or beginning of December. (b) female outnumbered male indoors (7.4:1) and V.V. outdoors (0.14:1). (c) blood fed females were 97.7% indoors and 29.4% outdoors. (d) the nocturnal activity ranged between 6 p.m. to 6 a.m. indoors and 8 p.m. to 6 a.m. outdoors. (e) the immature stages of Phlebotomus were successfully recovered from rodent burrows and poultry sheds.  相似文献   

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LargeT 2 (Al6Li3Cu) crystals which display apparent five-fold symmetry have been studied using several different electron microscopy techniques. Electron microprobe X-ray analysis was used to determine the phases present in two different alloys cast with bulk compositions close to stoi-chiometricT 2. Convergent beam electron diffraction (CBED) of these crystals indicates that they do not display five-fold rotational symmetry, and TEM images and selected area diffraction from thin foil specimens indicate a microcrystalline or twinned structure is responsible for the apparent five-fold symmetry ofT 2. Microdiffraction patterns obtained from the thinnest regions of the crystals are consistent with a cubic structure having a lattice parameter of ≈0.40 nm.  相似文献   

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The volume-mass properties of unwoven fibrous needle-pierced materials in and outside of the zones created as a result of the action of needles were calculated. The properties were determined using a volume approach. Equations were derived for calculation of the masses, the volume and mass concentrations of all and type 1 fibers, and other properties in the regions mentioned. Both single and multiple needle piercings were considered. A program was developed to carry out the indicated calculations.  相似文献   

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Two kinkajous (Potos flavus), which were separately owned as pets and fed an inappropriate diet consisting almost exclusively of succulent fruits developed cystic fibrous osteodystrophy of the jaw. In both cases there was a prominent enlargement of the chin and lower jaw, decalcification of facial bones, softening of the gingiva, and severe malocclusion, but no other relevant changes. Clinical, radiographic and histological findings were consistent with cystic fibrous osteodystrophy. The findings suggest that kinkajous with this condition are particularly prone to developing a bulbous enlargement of the chin as the main clinical sign, and that this change is histologically similar to the cystic form of the disease observed in man and monkeys.  相似文献   

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BACKGROUND: The rarity of pancreatic tumours other than nesidioblastosis in children is such that the experience of any one surgeon or institution is small. As a consequence, there is limited information on the appropriate management and outcome of these tumours. For this reason a review was conducted of the experience of a large paediatric surgical institution. METHODS: During a 23-year period, six patients with pancreatic tumours other than nesidioblastosis were treated at the Royal Children's Hospital, Melbourne. RESULTS: Despite the varied modes of presentation and surgery undertaken, all six patients with surgery alone, with follow-up from 1 to 18 years. Two of the tumours were malignant; the remaining four being islet cell adenomata. No form of adjuvant treatment (chemotherapy or radiotherapy) was used. CONCLUSION: These rare paediatric tumours appear to have a good prognosis, even when malignant, and respond well to radical surgical ablation. Adjuvant therapy appears to be unnecessary.  相似文献   

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