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91.
A multivariate study of protective effects of Zn and Cu against nephrotoxicity induced by cadmium metallothionein in rats. 总被引:3,自引:0,他引:3
X Y Liu T Y Jin G F Nordberg S R?nnar M Sj?str?m Y Zhou 《Toxicology and applied pharmacology》1992,114(2):239-245
Factorial experimental design was used to study the protective effects of Zn and Cu on cadmium-metallothionein(CdMT)-induced nephrotoxicity in male Wistar rats. In the factorial design two levels of Zn (0 and 25 mg/kg body weight), two levels of Cu (0 and 12.5 mg/kg), and two levels of CdMT (0.1 and 0.4 mg of Cd/kg) were used as varied factors. The factorial design was complemented with a center point with all three variables at an intermediate setting, i.e., Zn at 12.5 mg/kg, Cu at 6.25 mg/kg, and CdMT at 0.25 mg Cd/kg. Each of the nine combinations of settings was administered to one of nine groups with six rats in each. Zn and Cu were injected sc 24 hr prior to the injection of CdMT. The concentrations of protein and Ca in urine and Ca in renal cortex were used as effects. The relationship between the experimental design settings and the effects were modeled with multiple regression. The multiple regression analysis revealed that for the high dose of CdMT (i) the enhanced values of protein in urine caused by CdMT injection could be more efficiently reduced by Zn than by Cu, and (ii) excessive Ca in urine and renal cortex could be more efficiently reduced by Cu than by Zn. No significant synergism or antagonism between Cu and Zn was found. These models can be used to estimate the dose levels of Zn and Cu which will reduce the toxic effects of CdMT. The treatment of 20.4 mg/kg Zn, for example, will reduce the effects of 0.4 mg Cd/kg as CdMT on protein in urine, and 2.8 mg/kg Cu will reduce the Ca in urine to the levels of those caused by 0.25 mg Cd/kg (no Zn and Cu). Similarly, the effect of 0.4 mg Cd/kg on Ca level in renal cortex can be reduced to that of 0.28 mg Cd/kg as CdMT by 7.98 mg Cu/kg, which is three times as efficient as Zn. The obtained results might be of importance in understanding the mechanism of cadmium toxicity and the potential risk to the health of the population exposed to cadmium occupationally or environmentally. 相似文献
92.
A study on various symptoms of chronic hepatitis treated with radix astragali and its regulative effect to levels of serum hormone 下载免费PDF全文
Ke-zhou Liu Zhong-hang Tong Ming-tai Zhang Wei-zheng Gu Zhi-rong Huang Bi-he Shen Pei-ren Cai Gui-lang Zhu Wen-nan He Lan-sheng Feng Lie-ming Ding Zhi Chen Jian-hua Jin Xiu-zhi Zhang Qian-yan Yu Shui-jin Tong Ping Ye 《中国结合医学杂志》1995,1(2):118-121
Sixty-seven cases of chronic hepatitis were treated with Radix Astragali. After treatment (2-month course), the clinical improvement rate in 38 cases of the Stagnation of the Liver-Qi and Deficiency of the Spleen type was 92.1%, and in 26 cases of the Deficiency of Liver Yin and Kidney Yin type was 88.5%, more effective than in the control group (P<0.05). The regulative effect to the levels of serum hormone was observed in the patients of the Stagnation of the Liver-Qi and Deficiency of the Spleen type treated with this medicine. The results showed that the levels of serum triiodothyronine, estradiol (female) and testosterone (male) were increased after treatment (1.40±1.38 ng/dl, 129.30±1.23 pg/ml and 496.24±1.47 ng/dl). Pre-treatment levels were 1.22±1.49 ng/dl, 104.60±1.45 pg/ml and 398. 17±1.55 ng/dl respectively (P<0.05); however, the level of serum prolactin (2.75±4.46 ng/ml) was lower after treatment than before treatment (3.20±3.82 ng/ml,P<0.05). No obvious changes were observed in the levels of serum follicle stimulating hormone, luteinizing hormone, thyroid stimulating hormone, thyroxine, triiodothyronine uptake ratio and cortisol after treatment. 相似文献
93.
肺癌脑转移的CT研究 总被引:1,自引:0,他引:1
目的:研究分析肺癌脑转移瘤的CT特征和规律。材料与方法:回顾总结并分析经病理证实的74例肺癌脑转移病例,就其转移灶的CT特征和规律做出评价。结果:肺癌脑转移以顶、额叶为好发部位,转移灶主要表现为结节状均一强化和环状强化中心低密度,可单发或多发。瘤周水肿以腺癌和低分化癌较明显。环状强化中心低密度灶周水肿较结节均一强化灶周水肿明显。结论:CT增强扫描能清楚地显示转移灶的大小、部位、形态、边缘状况和密度变化,是肺癌脑转移的首选检查方法。 相似文献
94.
用二甲苯所致的急性炎症模型观察了神效止痛膏的抗急性炎症作用.用扭体法、热板法观察了神效止痛膏对小鼠的镇痛作用.结果表明,神效止痛膏有很好的镇痛作用. 相似文献
95.
目的 :研究低氧对体外培养的口腔鳞癌细胞系血管内皮生长因子 (vascularendothelialgrowthfactor ,VEGF)和明胶酶 A(matrixmetalloproteinase 2 ,MMP 2 )的影响。 方法 :分别用酶联免疫吸附实验 (ELISA)和半定量逆转录聚合酶链反应 (RT PCR)测定了低氧处理不同时间段时口腔鳞癌细胞系TSCCa和GNM细胞的细胞中VEGF和MMP 2的活性和mRNA表达情况。结果 :低氧处理 4h时 ,VEGF和MMP 2的活性便显著增加 ,8h时达到最高 ,GNM细胞中VEGF和MMP 2分别增加 2倍和 2 .5倍 ;而TSCCa细胞中VEGF和MMP 2增加的更为明显 ,分别增加了 6倍和 4倍。RT PCR结果显示GNM细胞VEGF和MMP 2mRNA表达水平均较TSCCa细胞高 (P <0 .0 5 ) ,低氧处理时在TSCCa细胞中VEGF和MMP 2增加的尤为明显。结论 :低氧可通过调节口腔鳞癌细胞VEGF和MMP 2的活性和mRNA的表达在口腔鳞癌血管形成中起重要作用 相似文献
96.
We investigate the role that the superior colliculus (SC) and the cerebellum might play in generating gaze shifts. The discharge of cells in the intermediate layers of the SC is tightly linked to the occurrence of saccades. Many studies have demonstrated that the cerebellum is involved in both eye and head movements. When the head is unrestrained, large amplitude gaze shifts are composed of coordinated eye and head movements. In this study, we propose that the gaze saccades system is controlled by a feedback loop between the SC and the cerebellum. The SC only encodes retinal coordinates and controls the eye displacement (to move the fovea to the target), while the cerebellum deals with the gaze programming and controls the head displacement. When a target appears in space, the buildup cells within the SC decode the target signal in the retina before the saccade onset, and input the signal of the gaze displacement to the cerebellum. The cells in the cerebellum vermis encode the initial position of the eye in the orbit. The gaze displacement is decomposed into the head amplitude and the eye amplitude within the cerebellum. There are two output signals from the cerebellum. One signal controls the head movement. The other is projected back to the SC, and forms a component of the saccade vector to control the eye movement. The sum of the vectors provided by the cerebellum and the vector provided by the burst cells in the SC indicates the direction and the amplitude of the desired movement of the eye during the saccade. We propose a cerebellum model to predict the displacements of the eye and head under the condition that the position of the target signal in the retina and the initial position of the eye in the orbit are known. The results from the model are close to that observed physiologically. We conclude that before gaze shift onset, the cerebellum may play an important role in decomposing the gaze displacement into an eye amplitude and head amplitude signal. 相似文献
97.
149例围产儿死亡原因分析 总被引:2,自引:0,他引:2
目的:探讨围产儿死亡原因及降低围产儿死亡率的措施。方法:对1994年1月-2001年12月在我院住院分娩的149例死亡围产儿的临床资料进行回顾性分析。结果:围产儿死亡率为22.74‰,死胎率为9.77‰,死产率为3.36‰,早期新生儿死亡率为9.62‰,占42.28%。围产儿死亡原因:缺氧占47.65%,早产占21.15%,出生缺陷占12.08%。结论:加强孕期保健、规范系统产前检查及监护、积极预防治疗妊娠并发症、防治早产、实施正确的新生儿窒息复苏方法、建立NICU等是降低围产儿死亡率的重要环节。 相似文献
98.
R F Lai A Fat M Harboe J C Chan Pin Jin M M Diesselhoff-den Dulk R van Furth 《International journal of leprosy and other mycobacterial diseases : official organ of the International Leprosy Association》1988,56(4):552-558
For the detection of the synthesis in vitro of anti-Mycobacterium leprae antibodies in various tissues of leprosy patients, biopsy specimens of skin lesions, nasal mucosa, larynx, lymph nodes, and bone marrow were cultured in a medium containing 14C-labeled lysine and isoleucine. The culture fluids were analyzed by crossed immunoelectrophoresis with intermediate gel and autoradiography. The results show that synthesis of anti-M. leprae antibodies occurs at the investigated sites of leprosy patients and that the specificities of the synthesized antibodies differ between sites in individual patients. It is conceivable that these antibodies play a role in the local defense against M. leprae. 相似文献
99.
本文报导了1983~1984年北京市城区(宣武区),近郊区(西红门)和远郊区(大皮营)母乳脂质成分的测定结果,并结合乳母营养状况给予评价。 共测定了207例母乳比重,平均范围在1.018~1.023之间;测定了216例母乳的脂肪含量(g/100g乳),城区平均值为3.78,近郊区为3.31,远郊区为3.08,城区的显著较高;测定了194例母乳胆固醇含量,初乳的最高(23.4mg/100g乳),以后逐渐减低,到第三个月后达稳定水平(约10mg/100g乳),三个调查点的情况相同,测定了221例母乳的脂肪酸组成,其主要成分为油酸(29~37%),棕榈酸(17~25%)和亚油酸(12~25%),远郊区母乳中所含的必需脂肪酸显著较高。 统计分析证明三个地区的乳脂含量(%)与乳胆固醇含量(mg/100g乳)间有显著性相关(P<0.01);188例乳母的膳食脂肪摄入量(g/日或%kcal)与乳脂含量间也有显著性相关(P<0.05),此结果表明,北京城乡母乳的乳脂含量可能受膳食脂质与量的影响,其脂肪酸组成的特点是亚油酸含量高,反映了我国人民以素食为主的饮食习惯。乳中的必需脂肪酸供给量可满足婴儿所需,胆固醇供给量为70~85mg/d,可作为同龄婴儿自母乳摄入量的参考。 相似文献
100.
载银磷酸锆纱布对烧伤创面常见细菌作用的实验研究 总被引:1,自引:1,他引:0
目的 了解载银磷酸锆纱布对烧伤大鼠创面感染常见细菌的抗菌效力。方法制作Wistar大鼠烫伤(以下称烧伤)感染模型,采用试管双倍稀释法测定载银磷酸锆及磺胺嘧啶银的最低抑菌浓度(MIC)及最低杀菌浓度(MBC)。观察大鼠创面用磺胺嘧啶银纱布、普通尢菌纱布、载银磷酸锆纱布(小水洗及水洗20次)后痂下组织的细菌计数和对创面愈合的作用。结果载银磷酸锆对金黄色葡萄球菌、铜绿假单胞菌、大肠竹菌的MIC各为8、8、16mg/L,MBC各为16、8、32mg/L,为磺胺嘧啶银的2~8倍?大鼠创面用未水洗的载银磷酸锆纱布覆盖后,痂下细菌计数比用磺胺嘧啶银纱布低91%,比普通无菌纱布低99%未水洗的载银磷酸锆纱布对创面愈合的作用明显优于其他两种纱布,且其痂下组织细菌计数与水洗20次的效银磷酸锆纱布比较,差异无显著性意义(P>0.05)。结论载银磷酸锆埘烧伤创面感染常见细菌有较强的抑制和杀灭作用,其敷料可作为治疗措施中新的选择。 相似文献