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101.
帕米膦酸二钠的合成   总被引:2,自引:1,他引:2  
目的:合成二钠3-氨基-1-羟基-亚丙基-二膦酸盐(帕米膦酸二钠)。方法:有,无溶剂的两种合成路线,并对工艺进行改进,所得产物经元素分析,红外光谱,质谱等分析确证结构。结果;两种路线均可合成目标化合物。路线A收率高于路线B。结论:溶剂的加入使本反应体系均一,有利于产物生成。  相似文献   
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自绵毛马兜铃(Aristolochia mollissima Hance)根茎中分得九个化合物,其中已报道的七个化合物是尿囊素、马兜铃内酯、绵毛马兜铃内酯、β-谷甾醇、马兜铃酸A、9-乙氧基马兜铃内酯和9-乙氧基马兜铃内酰胺,本文报道结晶K_3的化学结构,经光谱分析(IR,~1H-NMR,~(13)C-NMR,2D-NMR和MS),化学反应及X-衍射晶体分析,确证K_3为一个新骨架结构的倍半萜化合物,命名为马兜铃新内酯。  相似文献   
104.
1. The plasma brain natriuretic peptide (BNP) concentration is elevated in patients with essential hypertension and normal systolic function. This may be related to left ventricular hypertrophy or diastolic dysfunction, both of which commonly occur in hypertension. 2. Echocardiography was performed on 32 patients with newly diagnosed untreated mild-to-moderate hypertension (19 men, 13 women; mean±SD age 51±15 years; diastolic blood pressure 99±12mmHg; systolic blood pressur. 153.2±18.0 mmHg; plasma creatinine 86±15 μmol/L; creatinine clearance 92.2±20.5 mL/min; left ventricular mass index 116±28 g/m2; left ventricular ejection fraction 66±9%). A 15 mL peripheral venous blood sample was obtained at the time of echocardiography for radioimmunoassay of BNP. 3. Sixteen patients had abnormal Doppler transmitral flow (E/A rati. < 1) and a higher median plasma BNP concentration compared with those patients with E/A ≥1 (12.9 vs 5.9 pmol/L, respectively; P = 0.006). The plasma BNP level correlated significantly with E/A ratio (r = -0.50; P = 0.035). Multivariate analysis showed that the E/A ratio is related to plasma BNP, independent of age and blood pressure. 4. Our results suggest that the plasma BNP level is influenced by diastolic dysfunction. Further studies are needed to determine whether assay of plasma BNP helps to identify patients with diastolic dysfunction.  相似文献   
105.
Bone marrow transplantation in animals has been shown to generate epithelial populations, a phenomenon that has also recently been suggested to take place after human hematopoietic cell transplantation. However, reports in humans are not conclusive because they still leave open the possibility that the identified donor-derived cells are not epithelial cells but intraepithelial lymphocytes. Here, we demonstrate that donor-derived CD45(+) hematopoietic cells in close contact with epithelial tissue may be falsely characterized as donor-derived epithelial cells if the three-dimensional structure of the tissue is not considered and the hematopoietic markers are not examined. By using a rigorous three-dimensional analysis on single sections of colon biopsies triple stained with donor-specific, epithelial-specific, and hematopoietic-specific markers we demonstrate that chimerism of colon epithelium is a real phenomenon occurring constantly after human hematopoietic cell transplantation. We exclude horizontal DNA transfer or cell fusion as the underlying mechanism of our findings. Tissue damage enhances the engraftment of the donor-derived epithelial cells. The physiological and therapeutical role of the donor-derived epithelial cells after human hematopoietic cell transplantation needs further investigation. However, their identification requires stringent and unequivocal detection systems.  相似文献   
106.
1对象和方法1.1 对象 本组共160例,女性146例,男性14例.72例为双侧单睑,88例为双上睑皮肤松驰,平均年龄37(18~56)岁.1.2 方法 嘱患者微闭眼下视,用美篮在睑缘上方6mm~8mm处画一条平行于睑缘的切口线,内中1/3交界处为最...  相似文献   
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Among cellular second messengers inositides play key roles in signal transduction pathways. Indeed, nuclear phosphoinositide- specific phospholipase C (PI-PLC) β1 and Akt are involved in cell cycle progression and apoptosis. Nuclear lipid metabolism has raised interest in the last years, mainly because of its link with haematopoietic progenitor cells. Myelodysplastic syndromes (MDS) are stem-cell clonal diseases characterized by an impaired hempoiesis and a differentiation defect in one or more of the bone marrow lineages, often leading to progression to acute myeloid leukaemia (AML). The MDS evolution to AML is not completely understood but, at a molecular level, the nuclear inositide signalling pathways can play an important role in this process.  相似文献   
110.
The expression of the anti-apoptotic molecules Bcl-2 and transforming growth factor-beta 1 is known to confer protective effects on the cerebral ischemia-reperfusion injury.The current study investigated the expression levels of Bcl-2 and transforming growth factor-beta 1 in response to multiple pre-ischemia electro-acupuncture at acupoints Zusanli(ST36)and Fengchi(GB20) stimulation.Rats were divided into five groups:uninjured,control,non-acupoint,GB20 and ST36. Rats in the non-acupoint,GB20 and ST36 groups received 30 minutes(3 times or 18 times)of electro-acupuncture stimulation before experimental cerebral ischemia was induced.Bcl-2 and transforming growth factor-beta 1 were found to be significantly increased in the ST36 groups with either 3 or 18 electro-acupuncture treatments(P<0.05).The production was higher with 18 electro-acupuncture treatments in the ST36 groups(P<0.05).In the GB20 groups,significant increase was only observed in transforming growth factor-beta 1 with 18 electro-acupuncture treatments(P<0.05).No significant elevation of the level of transforming growth factor-beta 1 was observed in the non-acupoint groups.However,the production of Bcl-2 increased with 18 treatments in the non-acupoint groups(P<0.05).The data suggest that multiple pre-ischemia electro-acupuncture at ST36 was effective in conferring neuroprotective effect on the brain by means of upregulation of Bcl-2 and transforming growth factor-beta 1 and the effect was increase with the number of treatment.  相似文献   
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