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161.
In this work, an attempt has been made to study the subchronic effects of arsenic exposure on the biochemical composition; mainly proteins of the liver tissues of Labeo rohita fingerlings by using Fourier transform infrared (FT‐IR) spectroscopic technique. The study was carried out using a Perkin Elmer‐Spectrum Rx1 spectrometer. Because of arsenic exposure, significant reductions in the intensity as well as area of amide bands have been observed in the liver tissues. The decreased intensity of the amide bands could be interpreted as the result of alteration of the protein synthesis due to the high affinity of metal compounds towards different amino acid residues of proteins. Further, meso‐2, 3‐dimercaptosuccinic acid (DMSA) treatment shows the recovery of the protein content in the liver tissues. To confirm that the changes observed are only due to the bio‐accumulation of arsenic, the concentration of arsenic in the liver tissues of Labeo rohita was determined by using Inductively Coupled Plasma‐Optical Emission Spectrometry (ICP‐OES). It is observed that the arsenic level in the control tissues is found to be below detectable limit, whereas the arsenic exposed liver shows an accumulation of 66.68 ± 0.43 μg/g and DMSA treatment reduces the arsenic content to 17.96 ± 0.19 μg/g. In conclusion, this study gives clear evidence that the use of FT‐IR spectroscopy is a powerful approach to achieve more insight into the protein alterations caused by arsenic. © 2009 Wiley Periodicals, Inc. Environ Toxicol, 2011.  相似文献   
162.
This is the first reported case in the literature to combine the use of a well established therapy to achieve wound healing (ie hyperbaric oxygen treatment) and a novel sprayed keratinocyte suspension technique to treat a challenging wound successfully. The merits and potential issues associated with these treatments are outlined and the case is detailed.  相似文献   
163.
In a phase IIIb clinical trial of the ultrasound contrast agent Levovist® (Schering AG, Berlin, Germany), the role of Levovist® in the management of patients with clinically suspected hepatocellular carcinoma (HCC) was evaluated and its efficacy was assessed. The assessment included the duration of diagnostically usable Doppler signal enhancement, and safety and tolerance of intravenous administration. All patients with clinically suspected hepatocellular carcinoma were referred for Doppler sonographic examination over a 5-month period and lesions with absent or suboptimal Doppler signals were included in the trial. A total of 300 mg/mL in concentration (8.5 mL) of Levovist® was administered through a peripheral vein while Doppler signal intensity in the lesion, based on a visual score, was recorded. Blood pressure and pulse were recorded before and after injection. Thirty-eight patients were examined, of which 29 were included in the trial. The lesions were subsequently proven histologically to be 19 HCC, one cholangiocarcinoma, two regeneration nodules and one colonic metastasis. For six patients in whom histological proof was not available, the diagnosis of HCC was suggested based on markedly elevated serum alpha-fetoprotein levels. All but one (96%) of the 25 HCC demonstrated increased Doppler signal after Levovist®. There were no Doppler signals before and after Levovist® injection in three non-HCC lesions (two regeneration nodules and one colonic metastasis). Two patients (6.9%) suffered minor adverse reactions of nausea and vomiting. The results show that Levovist® is safe and is able to improve lesion characterization and increase diagnostic confidence of hepatocellular carcinoma by enhancing tumour vascularization Doppler signal intensity.  相似文献   
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陈佩林  彭司勋  杨祯祥 《药学学报》1992,27(12):895-902
以天然血管紧张素转化酶抑制剂(ACEI)I5B2,WF-10129为先导化合物,结合现有ACEI的结构特征,设计和合成了含缬-酪-酪(Ⅰ1~4)和缬(丙)-酪(Ⅱ1~6)肽类化合物。初步药理试验表明,Ⅱ类化合物体外均有不同程度抑制ACE的活性,其中以Ⅱ5活性最强(IC50=7.9×10-10mol/L),体内抑制血管紧张素Ⅰ(AI)的升压活性也以Ⅱ5和Ⅱ4最强,与卡托普利相仿。  相似文献   
167.
BACKGROUND: Passive transfer of antibody to hepatitis C virus (HCV) has been thought to occur after infusion of human intravenous immunoglobulin (IVIG), as anti-HCV and/or HCV RNA was commonly found in that product. Recently, however, HCV RNA was detected in the serum of recipients of IVIG. Establishment of a causal relationship between IVIG therapy and HCV infection in recipients was attempted. STUDY DESIGN AND METHODS: Anti-HCV and HCV RNA sequences were investigated in serum samples from 39 persons who received a human IVIG product in seven different hospitals in Spain. HCV RNA was also investigated in two batches of the IVIG shared by some recipients. All the viral RNA detected were characterized with a line probe assay, restriction fragment length polymorphism analysis of the 5'-noncoding and core regions, and sequencing of the nonstructural 5 region. RESULTS: On the basis of both clinical and laboratory data, a relationship could be established between the IVIG therapy and the acquisition of the HCV infection by the recipients. Several HCV strains were detected among the recipients, with most of the recipients coming from the same hospital presenting with closely related strains. Moreover, an HCV strain almost identical to the main strain detected among the recipients was found in one batch of the IVIG that probably was shared by most of them. Follow-up studies and evaluation of low-avidity anti- HCV IgG suggested that both acute primary infections and reinfections were produced. In one case, direct evidence of reinfection by a different HCV strain was obtained. CONCLUSION: The results did not exclude the possibility that a second HCV strain associated with a further, unidentified batch of the IVIG could have contributed to this outbreak.  相似文献   
168.
Prevalence of Babesia antibody in a selected blood donor population   总被引:6,自引:0,他引:6  
Human babesiosis, a parasitic disease transmitted by the tick, Ixodes dammini, was confined previously to limited areas of the northeastern United States. It is a rare but potentially life-threatening complication of transfusion. Red cells and platelets prepared from asymptomatic donors have been implicated in transfusion-transmitted cases. More cases of babesiosis are being reported as the range of the vector expands in the United States. Blood donors from an endemic area were tested for antibody to Babesia microti during the summer. Only 3.7 percent of the 779 donors were seropositive, compared with 4.7 percent (p greater than 0.05) of donors from a nonendemic area. An epidemiologic survey of seropositive and matched seronegative controls demonstrated no significant differences that would assist in screening donors.  相似文献   
169.
Extension of vessels through hepatic neoplasms: MR and CT findings   总被引:1,自引:0,他引:1  
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170.
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