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21.
构建Loa22基因去信号肽片段原核重组表达载体   总被引:1,自引:0,他引:1  
目的:构建赖型钩端螺旋体OmpA膜蛋白Loa22基因去信号肽片段的原核表达载体,并对其进行克隆表达。方法:实验于2004—12/2005—12在四川大学华西医学中心感染免疫研究室完成。以赖型钩端螺旋体017株基因组DNA为模板,PCR扩增Loa22基因去信号肽片段,亚克隆至原核表达载体pGEX-4T-1,经双酶切、PCR鉴定,筛选出阳性重组质粒克隆。经DNA测序正确后,转化大肠杆菌,利用IPTG进行诱导表达,通过SDS—PAGE鉴定表达产物。结果:PCR获得长516bp的片段。Loa22基因去信号肽片段与pGEX-4T-1的重组质粒构建成功。重组质粒经IPTG诱导后能在大肠杆菌中表达Mr45000的融合蛋白。结论:制备了Loa22基因去信号肽片段原核重组表达载体,为钩体新型疫苗的研究奠定基础。  相似文献   
22.
Wright  DG; Kenney  RF; Oette  DH; LaRussa  VF; Boxer  LA; Malech  HL 《Blood》1994,84(4):1257-1267
Recombinant human granulocyte colony-stimulating factor (G-CSF) treatment has been shown to increase average neutrophil counts substantially in patients with childhood-onset cyclic neutropenia (or "cyclic hematopoiesis"), but not to eliminate the cyclic oscillations of neutrophil counts or those of other blood elements (monocytes, platelets, eosinophils, and reticulocytes) that are characteristic of this hematopoietic disorder. Indeed, oscillations of neutrophil counts are amplified during G-CSF treatment. We have compared the effects of recombinant granulocyte-macrophage-CSF (GM-CSF) with those of G-CSF in three patients with this disease (2 men and 1 woman, 17, 30, and 32 years of age). These patients were treated with GM-CSF (2.1 micrograms/kg/day, subcutaneously) for 6 weeks, preceded and followed by 6 to 13 weeks of detailed observation to document changes in the cyclic oscillations of blood neutrophils and other blood elements; two of the patients were subsequently treated with G-CSF (5.0 micrograms/kg/d, subcutaneously) and observed for comparable periods of time. Unlike G-CSF treatment, which increased average neutrophil counts more than 20-fold, GM-CSF increased neutrophil counts only modestly, from 1.6- to 3.9-fold, although eosinophilia of varying prominence was induced in each patient. However, at the same time, GM-CSF treatment dampened or eliminated the multilineage oscillations of circulating blood elements (neutrophils, monocytes, platelets, and/or reticulocytes) in each of the patients. In contrast, G-CSF treatment of the same patients markedly amplified the oscillations of neutrophil counts and caused the cycling of other blood elements (monocytes in particular) to become more distinct. These findings support the conclusion that the distinctive cycling of blood cell production in childhood-onset cyclic neutropenia results from abnormalities in the coordinate regulation of both GM-CSF-responsive, multipotential progenitor cells and G-CSF-responsive, lineage-restricted, neutrophil progenitors.  相似文献   
23.
ABSTRACT. In general, prostanoids act as local mediators, not as circulating hormones. A specific exception to this rule is the infusion of prostaglandin E1 in patients with ductus arteriosus-depend-ent pulmonary or systemic blood flow associated with congenital heart disease. We therefore measured prostaglandin E, plasma levels by gas chromatography-mass spectrometry during effective infusion of prostaglandin E1 in 10 neonates. Prostaglandin E1 plasma levels ranged from 22 to 530 (median 56) pg/ml in these patients. Since prostaglandin E1 is not synthesized endogenously to any significant extent, these plasma concentrations constitute genuine circulating levels not confounded by the common problem of e vivo artifacts. If endogenous prostanoids (e.g. prostaglandin E2) are suspected as circulating mediators, plasma levels detected by reliable methods ought to be in the same range as prostaglandin E1 plasma levels in the present investigation.  相似文献   
24.
Plasma glucose concentrations at birth and at two hours of age were measured in 53 infants of insulin-dependent mothers (IDMs). The plasma glucose concentrations at delivery were measured in the mothers of 17 IDMs and in the remaining 36 mothers, glucose was estimated by interpolation from concentrations achieved just before and after delivery. Clinical and laboratory data from the two groups were otherwise similar, so the groups were combined for further analyses. The maternal plasma glucose at delivery correlated positively with the glucose concentration of the IDMs at birth (Q=0.82, p <0.001) and negatively with the glucose concentration at two hours of age (Q= -0.46, p <0.001). Maternal plasma glucose concentration was higher in mothers delivered by caesarean section than in vaginally delivered mothers ( p <0.05). Eleven IDMs became hypoglycaemic at two hours of life (plasma glucose ≥1.7 mmol/1). These infants had higher cord plasma glucose concentrations at birth than those who remained normoglycaemic; the maternal glucose concentration was also higher. None of the IDMs became hypoglycaemic if the maternal glucose concentration at delivery was less than 7.1 mmol/l. In 28 IDMs the simultaneous plasma concentrations of non-antibodybound immunoreactive insulin (IRI) were recorded. Cord plasma IRI correlated with glucose and IRI at two hours of age (Q=-0.73, p <0.001 and Q=0.77, p <0.001, respectively). Cord plasma IRI was higher in IDMs who became hypoglycaemic than in the remaining infants. The results suggest that among the factors which may be responsible for neonatal hypoglycaemia in IDMs a major factor may be the maternal plasma glucose concentration at the time of delivery.  相似文献   
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27.
Neonatal screening for phenylketonuria (PKU) has created a problem as females with PKU are reaching child-bearing age. Surveys have revealed that maternal phenylalanine blood concentrations greater than 1200 μmol/l are associated with fetal microcephaly, congenital heart defects and intrauterine growth retardation. It is estimated that as many as 3000 hyperphenylalaninemic females may be at risk of producing these fetal abnormalities. To examine this problem, the international maternal PKU collaborative study was developed to evaluate the efficacy of a phenylalanine-restricted diet in reducing fetal morbidity. Preliminary findings have indicated that phenylalanine restriction should begin before conception for females with PKU planning a pregnancy. Dietary control should maintain maternal blood phenylalanine levels between 120 and 360 μmol/l and should provide adequate energy, protein, vitamin and mineral intake. Pregnant hyperphenylalaninemic females who achieved metabolic control after conception or by the 10th week of pregnancy had a better offspring outcome than anticipated. The results of 402 pregnancies are reviewed.  相似文献   
28.
Controversies in transfusion medicine. Perioperative hemodilution: pro   总被引:4,自引:0,他引:4  
Hemodilution can obviate the need for allogeneic transfusion in some patients. However, it is only one component of a comprehensive blood conservation program and should be combined with other techniques whenever possible. While most often employed in teenagers and healthy young adults, ANH has been used in small children, the elderly, and patients of all ages who are undergoing cardiac surgery. Extreme caution should be exercised if ANH is used in patients with coronary artery disease or aortic stenosis who are undergoing noncardiac surgery, because their normal compensatory mechanisms are impaired. What usually is a safe and relatively simple procedure can become a disaster if employed in inappropriately selected patients. Careful hemodynamic monitoring and maintenance of normovolemia are critical.  相似文献   
29.
引用违法传递概念设计合成了11个C-末端含氧代赖氨酸二肽,进行抗深部致病菌-白念珠菌活性试验,体外实验结果显示极强的抑菌活性,MIC在12.5~0.8μg/disk之间,较母体氧化赖氨酸大50~135倍(克分子比。  相似文献   
30.
ABSTRACT. We examined whether the abnormal regulation of the cardiovascular system and plasma noradrenaline observed after oral glucose in insulin-dependent diabetic patients could be normalized by intravenous infusion of insulin. Eight patients with type 1 (insulin-dependent) diabetes were examined after an oral glucose load with and without simultaneous infusion of insulin. Insulin infusion increased plasma insulin from 0.07 to 0.31 nmol/1. In the control experiment (glucose only), mean heart rate and mean arterial systolic blood pressure remained unchanged and plasma noradrenaline (NA) decreased (p < 0.05). After oral glucose plus intravenous insulin, mean heart rate increased by 11 % and mean systolic blood pressure by 5 % (p < 0.05, p < 0.01), whereas plasma NA did not change significantly. The present study indicates that physiologic increments in plasma insulin concentration are of importance in the regulation of the cardiovascular system and plasma NA following an oral glucose load.  相似文献   
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