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1.
To determine if clinically observed disorders in heme biosynthetic enzymes, known as sporadic porphyria cutanea tarda (PCT), could be reproduced in experimental animals, male Fischer rats were treated with ethanol, estrogen and hexachlorobenzene (HCB). A series of heme biosynthetic enzymes were assayed. In the rats given free access to 8% ethanol-drinking water for 15 weeks, -aminolevulinate (ALA) dehydratase was significantly reduced in erythrocytes. In the liver, ALA synthetase and uroporphyrinogen (UROgen) decarboxylase activities remained unchanged. In bone marrow cells, these activities did not change markedly. In the rats treated with estrogen (1 mg estrioltripropionate /rat/week, IM), no body weight gain was observed during the treatment for 15 weeks and urinary ALA excretion increased to 1.7 fold over normal level. In the liver, a significant increase was observed in the activity of ALA dehydratase, but other enzymes remained within the normal level. In bone marrow cells and erythrocytes, ALA dehydratase was also increased. ALA synthetase increased only in bone marrow cells to 2.1 times higher than the control level. In rats fed 0.3% HCB-diet for 8 weeks, urinary excretion of ALA, coproporphyrin and uroporphyrin increased to 2.4, 3.3 and 3.8 times higher than the controls, respectively. In the liver, an increase was observed in ALA synthetase, while a decrease was observed in ALA dehydratase and UROgen decarboxylase. In bone marrow cells and erythrocytes, ALA dehydratase was reduced and activities of other enzymes did not show any changes.These results indicate that alcohol, estrogen and HCB do not produce phenomena similar to those observed clinically in PCT.  相似文献   
2.
目的 :评价卡马西平治疗躁狂发作的疗效和副反应。方法 :对符合 CCMD- 2 - R情感性障碍躁狂发作诊断标准的 172例患者随机分成卡马西平组 (10 2例 )和碳酸锂组 (70例 ) ,治疗 4周 ,使用Bech- Rafaelsen躁狂量表和临床疗效总评量表评定疗效 ,用副反应量表及有关实验室检查评定副反应。结果 :两组疗后 4周 BRMS总分减分率显著低于疗前 (P<0 .0 1) ,说明卡马西平能有效治疗躁狂发作 ,疗效与碳酸锂相近。卡马西平主要的副反应以消化系统为多 ,表现为恶心、呕吐 ,次之发晕、困倦、共济失调等 ,与碳酸锂相似 ,但持续时间短 ,病人易耐受。结论 :卡马西平可作为情感性障碍躁狂发作的选用药物  相似文献   
3.
Photoacoustic Fourier transform infrared (PA-FT-IR) depth profiling spectra of the enamel of an intact human tooth are obtained in a completely nondestructive fashion. The compositional and structural changes in the tissue are probed from the enamel surface to a depth of about 200 m. These changes reflect the state of tissue development. The subsurface carbonate gradient in the enamel could be observed over the range of about 10–100 m. The carbonate-to-phosphate ratio increases in the depth profile. The depth profile also reveals changes in the substitutional distribution of carbonate ions. Type A carbonates (hydroxyl substituted) increase relative to type B carbonates (phosphate substituted) with increasing thermal diffusion length. In addition to the changes in the carbonate ion distribution and content, the PA-FT-IR depth profile clearly indicates a dramatic increase in the protein content relative to the phosphate content with increased depth. The changes in the carbonate content and distribution, along with the changes in the protein content, may be responsible for the changes observed in the apatitic structure in the depth profile of the enamel.  相似文献   
4.
5.
Lead was administred to adult female rats in drinking water (0;0.1:1 and 10 ppm) for 3 weeks before mating, during pregnancy and during 3 weeks after delivery. On day 21 after delivery the mothers and their newborns were sacrified and various parameters of blood -- lead concentration on (Pb-B), hematocrit (Htc), hemoglobin (Hb), free erythrocyte porphyrins (FEP), delta0aminolevulinate dehydratase (ALAD) -- and tissue -- ALAD, free tissue porphyrins (FTP), lead concentration (Pb-T) -- were determined. In mothers a significant increase in Pb-B and Pb concentration in kidney was found in the 10 ppm group, but this increase in lead concentration was not associated with any statistically significant modification of the biochemical parameters. In newborns, lead concentration in blood and in kidney was also significantly increased in the 10 ppm group and this lead exposure was associated with a decrease of the ALAD activity in blood and an increase of FTP in kidney. On the basis of the biochemical parameters investigated one can therefore conclude that the developing organism is more susceptible to the biological action of lead than the organism of adult animals and that the "no-effect" level of lead administered during pregnancy and in the neonatal period is around 1 ppm.  相似文献   
6.
Acidic proteins are generally thought to control mineral formation and growth in biocalcification. Analysis of proteinaceous components in the soluble and insoluble matrix fractions of sclerites in Sinularia polydactyla indicates that aspartic acid composes about 60% of the insoluble and 29% of the soluble matrix fractions. We previously analyzed aspartic acids in the matrix fractions (insoluble = 17 mol%; soluble = 38 mol%) of sclerites from a different type of soft coral, Lobophytum crassum, which showed comparatively lower aspartic acid-rich proteins than S. polydactyla. Thus, characterization of highly acidic proteins in the organic matrix of present species is an important first step toward linking function to individual proteins in soft coral. Here, we show that aspartic-acid rich proteins can control the CaCO3 polymorph in vitro. The CaCO3 precipitates in vitro in the presence of aspartic acid-rich proteins and 50 mM Mg2+ was verified by Raman microprobe analysis. The matrix proteins of sclerites demonstrated that the aspartic-acid rich domain is crucial for the calcite precipitation in soft corals. The crystalline form of CaCO3 in the presence of aspartic acid-rich proteins in vitro was identified by X-ray diffraction and, revealed calcitic polymorphisms with a strong (104) reflection. The structure of soft coral organic matrices containing aspartate-rich proteins and polysaccharides was assessed by Fourier transform infrared spectroscopy. These results strongly suggest that the aspartic acid-rich proteins within the organic matrix of soft corals play a key role in biomineralization regulation.  相似文献   
7.

Objectives

To investigate and clarify physical and chemical properties of enamel affected by molar incisor hypomineralisation (MIH).

Methods

A series of in vitro studies were performed on extracted molars affected by MIH and sound teeth for controls. Tooth sections underwent Vickers microhardness testing before lapping and subsequent transverse microradiographic analysis and examination under polarised light microscopy. Carbonate content was determined by CO2 release from acid digestion. Unprepared and fractured surfaces were examined under scanning electron microscopy.

Results

MIH-affected molars demonstrated a severe degree of hypomineralisation with an average mineral content of only 58.8% vol% mineral. Vickers microhardness was significantly reduced in MIH compared with controls (1.8 ± 1.1 v 4.4 ± 1.0 GPa, p < 0.05) and polarised light microscopy revealed the bulk of MIH lesions had a porosity of ≤5% but also substantial areas of ≥10% and smaller areas exceeding 25% porosity. A surface layer was frequently observed on both intact and broken-down lesions and cervical regions of MIH teeth were typically spared. Carbonate content of MIH enamel was higher than control samples (6.6 ± 2.1 v 4.4 ± 1.1 wt%, p < 0.05). Scanning electron microscopy showed that both the enamel rod and surface ultrastructure were defective. Clinical characteristics did not consistently correlate with all properties.

Conclusions

The properties of MIH-affected enamel significantly differ from those of normal enamel and were highly variable, however some common characteristics were observed. Implications for aetiology and clinical management are discussed.  相似文献   
8.
目的 探讨烟酰胺片联合碳酸司维拉姆片治疗血液透析高磷血症的临床疗效。方法 选取2016年3月—2017年3月在云阳县人民医院肾内科维持血液透析的高磷血症患者100例作为研究对象,所有患者随机分为对照组和治疗组,每组各50例。对照组患者餐中口服碳酸司维拉姆片,用量根据具体血磷水平进行调整(当血磷≥2.41 mmol/L,口服剂量为1 600 mg/次;当血磷<2.41 mmol/L,口服剂量为800 mg/次),3次/d;治疗组患者在对照组治疗的基础上口服烟酰胺片,500 mg/次,1次/d。两组患者均连续治疗2个月。观察两组患者的临床疗效,比较治疗前后的血清学指标、冠状动脉钙化积分(CACS)、白细胞介素-6(IL-6)和甲状旁腺激素(PTH)水平。结果 治疗后,对照组和治疗组的临床总有效率分别为78.00%、94.00%,两组比较差异具有统计学意义(P<0.05)。治疗后,两组患者的血磷、钙磷乘积水平均显著降低,血钙水平显著升高,同组治疗前后比较差异具有统计学意义(P<0.05);且治疗后治疗组血清学指标显著优于对照组,两组比较差异具有统计学意义(P<0.05)。治疗后,两组患者的CACS、IL-6、PTH水平均显著降低,同组治疗前后比较差异具有统计学意义(P<0.05);且治疗后治疗组患者CACS、IL-6、PTH水平显著低于对照组,两组比较差异具有统计学意义(P<0.05)。结论 烟酰胺片联合碳酸司维拉姆片治疗血液透析高磷血症患者疗效显著,可显著降低血磷水平,减轻炎性反应,安全性较高,具有一定的临床推广应用价值。  相似文献   
9.
目的探讨药用炭片联合碳酸镧治疗血液透析高磷血症的临床疗效。方法选取2014年5月—2016年5月在驻马店市中心医院治疗的血液透析高磷血症患者160例,随机分为对照组(80例)和治疗组(80例)。对照组口服碳酸镧咀嚼片,1 g/次,3次/d;治疗组在对照组基础上口服药用炭片,1.5 g/次,3次/d。两组患者均经过12周。观察比较治疗前后两组患者临床疗效和血清学指标。结果治疗后,对照组和治疗组临床总有效率分别为81.25%、93.75%,两组比较差异具有统计学意义(P0.05)。治疗后,两组血磷、血钙、血甲状旁腺激素(PTH)、超敏C反应蛋白(hs-CRP)、成纤维生长因子23(FGF-23)和钙磷乘积水平均明显降低,同组治疗前后比较差异具有统计学意义(P0.05);且治疗组血清学指标低于对照组,两组比较差异具有统计学意义(P0.05)。结论药用炭片联合碳酸镧治疗血液透析高磷血症可有效改善患者生存质量,具有一定的临床推广应用价值。  相似文献   
10.
目的:评价碳酸钙、碳酸镧和盐酸司维拉姆三者在治疗高磷血症方面的经济性。方法:通过构建马尔可夫模型进行成本效果评价。结果:碳酸镧降磷效果最好,盐酸司维拉姆次之,碳酸钙最差,但考虑成本之后碳酸钙为最优方案。结论:在3倍人均GDP为支付阈值的条件下碳酸钙是最具有成本效果优势的方案。  相似文献   
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