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1.
Technical aspects of creating an arteriovenous fistula in the mouse are discussed. Under general anesthesia, an abdominal incision is made, and the aorta and inferior vena cava (IVC) are exposed. The proximal infrarenal aorta and the distal aorta are dissected for clamp placement and needle puncture, respectively. Special attention is paid to avoid dissection between the aorta and the IVC. After clamping the aorta, a 25 G needle is used to puncture both walls of the aorta into the IVC. The surrounding connective tissue is used for hemostatic compression. Successful creation of the AVF will show pulsatile arterial blood flow in the IVC. Further confirmation of successful AVF can be achieved by post-operative Doppler ultrasound.  相似文献   
2.
长江江豚野外健康状况的调查   总被引:5,自引:0,他引:5  
对铜陵江段捕获的7头长江江豚(Neophocaena phocaenoides asiaeorientalis)进行了体征与血液学分析。结果表明,健康的个体有2头,2头个体有明显的病变,余者营养不良,患不同程度的贫血症。这可能与长江渔业资源日趋枯竭有关。  相似文献   
3.
目的 通过雌二醇诱导SD雄鼠慢性前列腺炎,探讨SD雄鼠的内环境改变的关联性作用,为前列腺炎发生机制和治疗提供一条实验性途径.方法 3%戊巴比妥麻醉,无菌条件下去势手术;术后动物恢复5 d,30只雄鼠按照体重随机分组,每组10只.第6天低剂量组皮下注射0.25 mg/kg的雌二醇,高剂量组皮下注射1.25 mg/kg的雌二醇,溶媒对照组注射橄榄油,每天1次,连续30 d.结果 与溶媒对照组比较,低、高剂量组白细胞(WBC)、红细胞(RBC)、血红蛋白(HGB)和红细胞压积(HCT)均降低(P〈0.01);前列腺酸性磷酸酶(PAP)明显降低(P〈0.01);高剂量组睾酮含量明显增加(P〈0.01),C-反应蛋白(CRP)在低、高剂量组也呈现增加的趋势,但差异没有统计学意义;溶媒对照组和给药组前列腺组织大体解剖表面未见明显差异,光学显微镜下,溶媒对照组前列腺组织结构完整、腺腔和间质无炎性细胞浸润,高剂量组和低剂量组的前列腺间质均可见炎细胞浸润;低、高剂量组大鼠脾脏均可见棕黄色颗粒沉淀,其余脏器无明显改变,胸腺、脾脏及其脏器系数均明显降低.结论 根据本实验结果,雌激素引起的慢性非细菌性前列腺炎可导致内环境血液学、血清生化,激素水平、脏器和脏器系数的一系列改变.  相似文献   
4.
The 2-picolylamine is a simplest analogue of the alkaloid that has secondary and tertiary nitrogen function in its cyclic structure like that of alkaloids that can be derivatized to a number of biologically active compounds. In connection to our previous work, in the present work, three thiourea derivatives (I = 1,3-bis(2-benzyl-3-phenyl-1-(pyridine-2-yl) propyl) thiourea, II = 1,3-bis (pyridin-2-ylmethyl) thiourea, and III = 1-(2-benzyl-3-phenyl-1-(pyridine-2-yl) propyl)-3-phenylthiourea) were synthesized using 2-picolylamine template which is a readily available synthetic analogue of naturally occurring alkaloid. The biological effect of the synthesized derivatives were monitored on the activity of glucose-6-phosphatase in Swiss albino mice (21-days). The derivatives were also tested for their potential toxicity in a 28-days sub-chronic toxicity studies by assessing their effects on different parameters like hematological, serum biochemistry and liver histology. The therapeutic effect of the safe derivative (I) was examined in streptozotocin-induced diabetic mice as well. The derivatives showed inhibition of the enzyme activity from good to an excellent degree. Compound I had the highest inhibition with 21.42 ± 5.113 mg of the released phosphate as compared to that of the positive control group (84.55 ± 3.213 mg). Only I turned out to be safe for use in animals without exerting any toxic or lethal effects on any of the assessed parameters in the used animal model. Compound I efficiently reversed the effects like hyperglycemia, hyperlipidemia and weight loss in the test animals. Out of these three-tested compounds, I was found safe to be use as therapeutic agent in diabetes complications. However, further toxicological studies in other animal models are needed as well.  相似文献   
5.
Several studies on babies have shown that the type of delivery can influence the hematological and immune status of the newborn. In bovine medicine, some authors reported the hematological pattern of the newborn calf, but never related it with the calving process or other perinatal factors. The purpose of the present study was to evaluate the hematological profile in newborn calves in relation to the type of delivery. A total of 41 healthy calves were enrolled; 16 Friesian calves which were born by vaginal delivery without assistance (VD), and 25 Belgian Blue calves that were born by elective Caesarean section (CS). As soon as the calves were born, a complete clinical examination was performed to verify viability and maturity. At 10 min after birth, 2 mL venous blood was collected to perform the blood gas and acid-base evaluation. Blood samples were subsequently collected from the jugular vein within 30 min after birth, and at 1, 2, 3, 7, and 14 days of age. An automatic analyzer was used to determine hemoglobin concentration (Hb), hematocrit (Ht), and red and white blood cell counts, while differential leukocyte count was performed microscopically. Statistical analysis was applied to assess differences between the groups and within the group for all parameters between each sampling time (P ≤ 0.05). All the calves were born alive, viable, and mature. There were no acidotic calves, but statistical analysis revealed many differences, as higher pH, base excess (BE) (P ≤ 0.05), PO2 (P < 0.001), and sO2 (P < 0.0001) in the VD group. Levels of hemoglobin concentration, hematocrit, and red blood cell number were constantly higher in CS calves (P < 0.001). In comparison with the VD calves, white blood cell and neutrophil absolute number were higher at birth and at 14 days of age in the CS group (P < 0.001 and P ≤ 0.05). The mode of delivery, therefore, seems to have an influence on the oxygenation levels and on the hematological and nonspecific immunity profile of the newborn calf.  相似文献   
6.
Mutations in the erythroid-specific aminolevulinic acid synthase gene (ALAS2) cause X-linked sideroblastic anemia (XLSA) by reducing mitochondrial enzymatic activity. Surprisingly, a patient with the classic XLSA phenotype had a novel exon 11 mutation encoding a recombinant enzyme (p.Met567Val) with normal activity, kinetics, and stability. Similarly, both an expressed adjacent XLSA mutation, p.Ser568Gly, and a mutation (p.Phe557Ter) lacking the 31 carboxyl-terminal residues also had normal or enhanced activity, kinetics, and stability. Because ALAS2 binds to the β subunit of succinyl-CoA synthetase (SUCLA2), the mutant proteins were tested for their ability to bind to this protein. Wild type ALAS2 bound strongly to a SUCLA2 affinity column, but the adjacent XLSA mutant enzymes and the truncated mutant did not bind. In contrast, vitamin B6-responsive XLSA mutations p.Arg452Cys and p.Arg452His, with normal in vitro enzyme activity and stability, did not interfere with binding to SUCLA2 but instead had loss of positive cooperativity for succinyl-CoA binding, an increased K(m) for succinyl-CoA, and reduced vitamin B6 affinity. Consistent with the association of SUCLA2 binding with in vivo ALAS2 activity, the p.Met567GlufsX2 mutant protein that causes X-linked protoporphyria bound strongly to SUCLA2, highlighting the probable role of an ALAS2-succinyl-CoA synthetase complex in the regulation of erythroid heme biosynthesis.  相似文献   
7.
微囊藻细胞抽提液对小鼠血液的亚慢性毒性   总被引:1,自引:1,他引:0  
本文研究了注射含微囊藻毒素的微囊藻细胞抽提掖对小鼠血液以及免疫系统的亚慢性毒性作用。实验分为3个处理组和1个对照组(每组10只昆明小鼠,雌雄各半),采用腹腔注射的染毒方法对3个处理组进行暴露,剂量分别为2.4、4.8 和 9.6 μg microcystin-LR/kg body weigh,对照组注射等量的生理盐水,连续注射14d。实验结果表明,14d 染毒后,小鼠的肝体比和脾体比都明显增大(p < 0.05), 同时在9.6 μg/kg处理组,血清丙氨酸转移酶、天冬氨酸转移酶、乳酸脱氢酶和碱性磷酸酶活性与对照相比明显升高,但血清总蛋白、白蛋白和白蛋白/球蛋白比率下降。这些指标的变化说明,含微囊藻毒素的微囊藻细胞提取液对处理组小鼠肝脏造成了损伤,肝组织学观察也印证了这个结果,在处理组小鼠肝组织有明显的水样变性。另外,9.6 μg/kg处理组小鼠血液白细胞数量比对照组明显减少。组织细胞学观察发现,处理组小鼠脾脏也有明显的损伤。该实验结果说明,含微囊藻毒素的微囊藻细胞抽提液对小鼠的血液和免役系统都产生了一定程度的损伤。  相似文献   
8.
目的观察戊巴比妥钠、水合氯醛、氨基甲酸乙酯三种麻醉药物对雌性SD大鼠血液学指标的影响。方法选用戊巴比妥钠(40mg/kg)、水合氯醛(400mg/kg)、氨基甲酸乙酯(1g/kg)腹腔注射麻醉雌性SD大鼠,麻醉20min后眼眶静脉丛取血测定大鼠血液细胞学指标及血液生化指标。结果三种不同药物麻醉雌性SD大鼠20min后,某些血液细胞学指标及血液生化指标与生理盐水对照组相比均有不同程度的差异。结论麻醉药物可对雌性SD大鼠的血液学指标产生影响。  相似文献   
9.
Various human Burkitt lymphoma and LCL lines established in vitro and their derived somatic cell hybrids were tested for their comparative EBV receptor levels in a virus binding assay. Their graded C3b and C3d complement receptor expression was estimated simultaneously by means of isotope labeled rosette marker cells. The receptor concentration of each cell line was related to Raji as the standard of comparison, K 562, P3HR-1, and YACUT were used as negative controls. In general, the charging curves for EBV and C3d receptors parallelled each other (r = 0.97) while C3b receptor charging showed no correlation (r < 0.60). In the Raji hybrids between the C3b receptor positive Raji parent and various patents that were negative for this receptor, C3b receptor expression was low or negative. In contrast, the C3d negative P3HR-1 line gave rise to hybrids, after fusion with receptor-positive cells, that were intermediate with regard to their C3d receptor expression. The host range restriction of the Epstein-Barr virus is determined at the receptor level. The close relationship between the EBV receptor and the C3d receptor, a B-lymphocyte-specific moiety, suggests that the moderate interaction with EBV with the B lymphocytes may have had a selective advantage, favoring the presence of EBV. Since EBV causes lytic infections after artificial introduction into nonnatural host cells, it may represent a B-lymphocyte-specific host range mutant, derived from an originally lytic herpesvirus with a much broader target cell range.  相似文献   
10.
The carbohydrate structure of human thrombin has been determined by direct probe mass spectrometry of the oligosaccharides released by trifluoroacetolysis from the asialo glycoprotein. The free oligosaccharides were studied as permethylated and N-trifluoroacetylated oligosaccharide alditols. The structure was confirmed by sequential exoglycosidase digestion of intact thrombin and sugar and methylation analysis of the oligosaccharides by gas-liquid chromatography-mass spectrometry. The results indicate the following structure:
with Fuc present on only about 50% of the oligosaccharides.  相似文献   
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