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81.
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A monoclonal antibody (designated K:1-6F) generated by hybridization of mouse myeloma cells with spleen cells from mice immunized with the erythroleukemic cell line K562 was found by fluorescence-activated cell sorter analysis, dot-blot assay and electroimmunoblotting to bind to a majority of cells in the K562 and HEL erythroleukemic cell lines, to a subset of cells of the erythroid lineage from normal bone marrow, to a subset of cells in all analysed cases (total 10) of erythroleukemia, and weakly to cells from patients with myeloid leukemia. The antibody did not bind to normal erythrocytes, monocytes, T- and B lymphocytes or granulocytes, as well as a panel of human malignant cell lines of hemopoietic origin (HL60, U937, Daudi, Molt-3, RH-L4 and U266). Biochemical characterization of the antigen defined by the antibody suggests that eht epitope is defined by a carbohydrate structure alone or in combination with proteins. Four molecules with Mr 100 kD, 65 kD, 45 kD and 18 kD respectively were immunoprecipitated from Triton X-100 extract of K562 erythroleukemia cells. Neuraminidase did not affect the binding of the antibody, whereas tunicamycin reduced the K:1-6F expression. The K:1-6F Mab was in normal bone marrow found to be specific for erythroid precursor cells and may therefore be useful in examination of normal and leukemic erythropoiesis. 相似文献
83.
Jernström HC Johannsson OT Loman N Borg A Olsson H 《Breast cancer research and treatment》1999,58(3):293-299
Background: An early age at menarche, a short menstrual cycle length, and a high age at first full term pregnancy or nulliparity are known risk factors for breast cancer. These risk factors have previously been reported to differ between breast cancer patients with and without a family history of breast cancer and also between breast cancer patients and controls.
Methods: Self-administered questionnaires were filled out by 95 women belonging to 24 families with known BRCA1 mutations, 16 women belonging to nine families with known BRCA2 mutations, and 95 women belonging to 65 families with hereditary breast cancer where no BRCA1 or BRCA2 mutations could be detected. Thirty-nine women were BRCA1 mutation carriers and 56 women were BRCA1 negative, 11 women were BRCA2 carriers and five BRCA2 negative. All women were born between 1905 and 1979.
Results: Age at menarche, physiological menstrual cycle length at age 30 or at current age in younger women (when not using oral contraceptives), age at first full term pregnancy, and nulliparity did not significantly differ between BRCA1 mutation carriers and BRCA1 negative women. Too few women were BRCA2 negative to serve as a control group. BRCA2 mutation carriers were therefore compared with BRCA1 negative and BRCA2 negative women. None of the above reproductive factors did significantly differ between BRCA2 mutation carriers and from BRCA1 and BRCA2 families. Women from non-BRCA1/BRCA2 hereditary breast cancer families had a higher age at menarche, but this was no longer significant after adjustment for other factors in a multivariate model.
Conclusion: Our results suggest that reproductive risk factors of breast cancer are not related to BRCA1 or BRCA2 carrier status. There was also no indication that these factors differ in carriers of unknown susceptibility genes compared with non-carriers from BRCA1 and BRCA2 families. 相似文献
84.
Pierre Carmona Christian von Corswant Magnus Rding Aila Srkk Eva Olsson Niklas Lorn 《RSC advances》2022,12(40):26078
Porous phase-separated ethylcellulose/hydroxypropylcellulose (EC/HPC) films are used to control drug transport out of pharmaceutical pellets. The films are applied on the pellets using fluidized bed spraying. The drug transport rate is determined by the structure of the porous films that are formed as the water-soluble HPC leaches out. However, a detailed understanding of the evolution of the phase-separated structure during production is lacking. Here, we have investigated EC/HPC films produced by spin-coating, which mimics the industrial manufacturing process. This work aimed to understand the structure formation and film shrinkage during solvent evaporation. The cross-sectional structure evolution was characterized using confocal laser scanning microscopy (CLSM), profilometry and image analysis. The effect of the EC/HPC ratio on the cross-sectional structure evolution was investigated. During shrinkage of the film, the phase-separated structure undergoes a transition from 3D to nearly 2D structure evolution along the surface. This transition appears when the typical length scale of the phase-separated structure is on the order of the thickness of the film. This was particularly pronounced for the bicontinuous systems. The shrinkage rate was found to be independent of the EC/HPC ratio, while the initial and final film thickness increased with increasing HPC fraction. A new method to estimate part of the binodal curve in the ternary phase diagram for EC/HPC in ethanol has been developed. The findings of this work provide a good understanding of the mechanisms responsible for the morphology development and allow tailoring of thin EC/HPC films structure for controlled drug release.The EC/HPC/EtOH phase diagram could be estimated from the CLSM monitoring of the cross-sectional in situ phase separation. The findings of this work provide a good understanding of the structure evolution. 相似文献
85.
保证输血时血清学方面的安全,首要的是对受血者与献血者ABO血型定型,血清学检查通常分两个步骤.正定型通常使用鼠源单克隆抗体检测红细胞表面是否存在A或B抗原.互补的实验即反定型,利用当红细胞上缺乏A或B抗原时,人群可天然产生相对应的抗体的原理,检测血清中是否存在抗-A或者抗-B抗体.确定了受血者红细胞表面的ABO抗原以及血浆中的抗体,便能确定血型,为其提供相合的血液. 相似文献
86.
Agustina Heredia-Martinez Guillermo Rosa-Diez Jorge R. Ferraris Anna-Karin Sohlenius-Sternbeck Carina Nihlen Annika Olsson Jon O. Lundberg Eddie Weitzberg Mattias Carlstrm Rafael T. Krmar 《Nutrients》2022,14(12)
Nitric oxide (NO) contributes to maintaining normal cardiovascular and renal function. This bioactive signalling molecule is generally formed enzymatically by NO synthase in the vascular endothelium. NO bioactivity can also be attributed to dietary intake of inorganic nitrate, which is abundant in our diet, especially in green leafy vegetables and beets. Ingested nitrate is reduced to nitrite by oral commensal bacteria and further to NO systemically. Previous studies have shown that dialysis, by means of removing nitrate and nitrite from the body, can reduce NO bioactivity. Hence, dietary intervention approaches aimed to boost the nitrate–nitrite–NO pathway may be of benefit in dialysis patients. The purpose of this study was to examine the kinetics of plasma nitrate and nitrite after a single intake of nitrate-rich concentrated beetroot juice (BJ) in adult hemodialysis (HD) patients and in age-matched healthy volunteers (HV). Eight HD patients and seven HV participated in this single center, randomized, single-blind, placebo-controlled, crossover study. Each participant received a sequential single administration of active BJ (70 mL, 400 mg nitrate) and placebo BJ (70 mL, 0 mg nitrate) in a random order separated by a washout period of seven days. For the kinetic analysis, blood samples were collected at different time-points before and up to 44 h after BJ intake. Compared with placebo, active BJ significantly increased plasma nitrate and nitrite levels both in HD patients and HV. The area under the curve and the maximal concentration of plasma nitrate, but not of nitrite, were significantly higher in HD patients as compared with HV. In both groups, active BJ ingestion did not affect blood pressure or plasma potassium levels. Both BJs were well tolerated in all participants with no adverse events reported. Our data provide useful information in planning dietary nitrate supplementation efficacy studies in patients with reduced NO bioactivity. 相似文献
87.
88.
Summary Cellular accumulation of sulphatides after intracerebral and endoneurial injections of the lipid was shown to occur if mesenchymal cell proliferation is induced by cold injury to the brain or by transection of peripheral nerves. The cells accumulating the sulphatide in the brain were identified as mesenchymal phagocytes and in the peripheral nerves as endoneurial phagocytic cells.Accumulation of sulphatide was found in the epithelial cells of the renal collecting tubules after intracerebral injection of the lipid. This observation indicates that part of the renal sulphatide which can be demonstrated histochemically in the kidneys from cases of metachromatic leucodystrophy may derive from the brain and is excreted via the kidneys.
Zusammenfassung Celluläre Anhäufung von Sulfatiden nach intracerebralen und endoneuralen Injektionen des Lipids konnte nachgewiesen werden, wenn eine Proliferation von Mesenchymzellen durch Kälteverletzung des Gehirns oder durch Durchschneidung peripherer Nerven induziert wurde. Die mit Sulfatiden beladenen Zellen im Gehirn wurden als mesenchymale Phagocyten und in den peripheren Nerven als endoneurale Phagocytenzellen identifiziert.Anhäufung von Sulfatiden wurde nach intracerebraler Injektion des Lipids ferner in den Epithelzellen der Sammelstücke der Nierentubuli nachgewiesen. Dieser Befund weist darauf hin, daß ein Teil des renalen Sulfatides, das histochemisch in der Niere von Fällen metachromatischer Leukodystrophie nachgewiesen werden kann, teilweise aus dem Gehirn stammen könnte und über die Nieren ausgeschieden wird.相似文献
89.
90.