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41.
The extent of population diversity among GB virus C (GBV-C)/hepatitis G virus (HGV) within a persistently infected individual (Iw) was investigated by sequence analysis of multiple clones generated from polymerase chain reaction (PCR)-amplified products of cDNA analogous to fragments of 5 non-coding region (5NC), envelope region 1/2 (E1/E2) and non-structural region 3 (NS3) of viral genome. Although nucleotide substitutions were more common in coding regions than in the 5NC region, there was no region corresponding to the hypervariable region of hepatitis C virus in the E1/E2 region. Transition substitution exceeded transversion by 7 to 12-fold, and 79.4% of substitutions were synonymous. This bias against substitutions producing amino acid replacements and the use of Pfu DNA polymerase with an error rate 10 times lower than the observed frequency of substitution, suggests that most substitutions were not artefactual. This data suggests that individual genomes of HGV within an infected individual may differ from each other at 0.23–0.84% nucleotide position and at 0.42–0.61% amino acid position.  相似文献   
42.
A series of pseudo-peptide analogs of the Arg-Gly-Asp (RGD) sequence of fibronectin have been synthe-sized, and their anti-metastatic effects in mice and inhibitory effects on tumor cell invasion in vitro have been examined. The partially modified retro pseudo-peptide of RGD, Rrev-COCH2CO-D (FC-63), was more effective in inhibiting tumor metastasis than the original RGDS peptide. Replacement of the malonyl moiety of FC-63 with a carboxyethylene linkage (Rrev-COCH2CH2-D, FC-303 ) achieved more potent inhibition of lung metastasis of melanoma cells than FC-63. Among the analogs, FC-336, a p-xylylendiamine derivative having two FC-303 moieties, showed the most potent inhibitory effect on experimental lung metastasis produced by i.v. co-injection with B16-BL6 melanoma or colon 26 M3.1 cells in a dose-dependent manner. Multiple administrations of FC-336 after tumor inoculation also showed efficient therapeutic potency against spontaneous lung metastasis of B16-BL6 melanoma in mice. Furthermore, FC-336 effectively inhibited the invasion, migration and adhesion of tumor cells in vitro, but its inhibitory effects were not more than those of RGDS peptide. Zymography analysis revealed that FC-336 inhibited the degradation of gelatin substrate by matrix metalloproteinases (MMPs) produced by tumor cells, while the RGDS peptide did not affect the enzymatic degradation. These findings indicate that the pseudo-peptides of the RGD sequence, possessing the inhibitory property of the degradation by MMPs differently from original RGD-containing peptides, may be advantageous and useful in preventing tumor metastasis. © Rapid Science 1998  相似文献   
43.
BackgroundMyotubular myopathy is a rare disease sometimes accompanied by peliosis hepatis, a leading cause of fatal liver hemorrhage.Case ReportWe present a case of a 2-year-old boy with myotubular myopathy who developed liver hemorrhage because of peliosis hepatis and was successfully treated with living-donor liver transplant. The patient initially presented with fever, anemia, and liver dysfunction. A computed tomographic scan revealed hemorrhages in the liver, and the patient underwent hepatic artery embolization twice. After the second embolization, multiple peliosis hepatis cavities appeared in the left lobe of the liver that had increased in size. Therefore, the patient underwent ABO-incompatible living-donor liver transplant using a lateral segment graft from his father. The patient developed severe septic shock with an unknown focus on postoperative day 18, which resolved with antibiotic therapy. On postoperative day 62, he was discharged. Fourteen months after undergoing living-donor liver transplant, the patient showed no recurrence of peliosis hepatis.ConclusionsAlthough the long-term prognosis of peliosis hepatis due to myotubular myopathy after living-donor liver transplant remains unclear, liver transplant may be a curative treatment for patients with myotubular myopathy who have uncontrollable peliosis hepatis.  相似文献   
44.
Clinical and Experimental Nephrology - The data regarding oncological outcome in advanced renal cell carcinoma (RCC) arising in end-stage renal disease (ESRD) are limited. Patients diagnosed with...  相似文献   
45.
Pharyngeal cancer patients treated with intensity-modulated proton therapy (IMPT) using a model-based approach were retrospectively reviewed, and acute toxicities were analyzed. From June 2016 to March 2019, 15 pharyngeal (7 naso-, 5 oro- and 3 hypo-pharyngeal) cancer patients received IMPT with robust optimization. Simulation plans for IMPT and intensity-modulated X-ray therapy (IMXT) were generated before treatment. We also reviewed 127 pharyngeal cancer patients with IMXT in the same treatment period. In the simulation planning comparison, all of the normal-tissue complication probability values for dysphagia, dysgeusia, tube-feeding dependence and xerostomia were lower for IMPT than for IMXT in the 15 patients. After completing IMPT, 13 patients completed the evaluation, and 12 of these patients had a complete response. The proportions of patients who experienced grade 2 or worse acute toxicities in the IMPT and IMXT cohorts were 21.4 and 56.5% for dysphagia (P < 0.05), 46.7 and 76.3% for dysgeusia (P < 0.05), 73.3 and 62.8% for xerostomia (P = 0.43), 73.3 and 90.6% for mucositis (P = 0.08) and 66.7 and 76.4% for dermatitis (P = 0.42), respectively. Multivariate analysis revealed that IMPT was independently associated with a lower rate of grade 2 or worse dysphagia and dysgeusia. After propensity score matching, 12 pairs of IMPT and IMXT patients were selected. Dysphagia was also statistically lower in IMPT than in IMXT (P < 0.05). IMPT using a model-based approach may have clinical benefits for acute dysphagia.  相似文献   
46.
The in vitro cytotoxic properties of a newly synthesized demethylpodophyllotoxin derivative, 4-o-butanoyl-4-demethylpodophyllotoxin (BN 58705), were determined by using several human tumor cell lines of different histological origin and of different sensitivity to conventional chemotherapeutic drugs (Adriamycin andcis-diammine-dichloride platinum). BN 58705 is shown to be cytotoxic against various human tumor cell lines as assessed by the MTT assay. Furthermore, BN 58705 is shown to be cytotoxic against several drug-resistant tumor cell lines. BN 58705 is cytotoxic at concentrations 100- to 1000-fold lower than those of Adriamycin orcis-diammine-dichloride platinum required to achieve similar cytotoxicity. BN 58705 did not mediate DNA fragmentation of target cells, whereas the epipodophyllotoxin-like etoposide induced DNA cleavage by stabilizing the DNA-enzyme intermediate. Like vinca alkaloids, BN 58705 induced a block in the mitotic phase of the cell cycle. By comparison, BN 58705 exerted a stronger cytotoxic activity in vitro than did either etoposide, an epipodophyllotoxin, or vincristine, a vinca alkaloid. When BN 58705 was applied in vivo in mice, it resulted in low toxicity (50% lethal dose, 150 mg/kg). These results demonstrate than BN 58705 is cytotoxic to drug-resistant human tumor cell lines and is manyfold more potent than conventional drugs. The cytotoxic potency and low toxicity of BN 58705 are important criteria to establish its potential chemotherapeutic efficacy in vivo.Abbreviations cpm counts per minute - BN 58705 4-o-butanoyl-4-demethylpodophyllotoxin - MTT 3-(4,5-dimethyl-thiazoyl-2-yl)-2,5-diphenyl-tetrazolium bromide - OD optical density - TRIS TRIS (hydroxymethyl) aminomethane - EDTA ethylenediaminetetraacetic acid - FITC fluoresceinisothiocyanate - PI propidium iodide This work was supported by a grant from Institut Henri Beaufour, France  相似文献   
47.
Nucleos(t)ide analogs (NAs) cannot completely suppress the risk of hepatocellular carcinoma (HCC) in patients with chronic hepatitis B (CHB). This study aimed to identify the risk factors for HCC development in naïve CHB patients treated with current NA. Patients receiving NA (n = 905) were recruited retrospectively from the 17 hospitals of the Japanese Red Cross Liver Study Group. All treatment-naïve patients had been receiving current NA continuously for more than 1 year until the end of the follow-up. We analyzed the accuracy of predictive risk score using the area under receiver operating characteristic curve. The albumin–bilirubin (ALBI) score was significantly improved by NA therapy (−0.171 ± 0.396; p < 0.001 at Week 48). A total of 72 (8.0%) patients developed HCC over a median follow-up of 6.2 (1.03–15.7) years. An independent predictive factor of HCC development was older age, cirrhosis, lower platelet counts at baseline and ALBI score, and alpha-fetoprotein (AFP) at 1 year after NA therapy according to multivariate analysis. The accuracy was assessed using the PAGE-B, mPAGE-B, aMAP, APA-B, and REAL-B scores that included these factors. Discrimination was generally acceptable for these models. aMAP and REAL-B demonstrated high discrimination with 0.866/0.862 and 0.833/0.859 for 3- and 5-year prediction from the status of 1 year after NA therapy, respectively. Baseline age and platelet count, as well as ALBI and AFP one year after NA, were useful for stratifying carcinogenesis risk. The aMAP and REAL-B scores were validated with high accuracy in Japanese CHB patients.  相似文献   
48.
Health is one of the basic requirements for improvement in the quality of life. Since Bangladesh became independent, a policy for providing essential minimum health care to all has been actively pursued. An overview of Public Health Services in Bangladesh is presented in terms of: (1) a profile of the country, (2) an overview of public health, (3) medical care, and (4) environmental health. Under each of these headings observations are included on recent trends based upon relevant data and information. Finally the authors describe the importance of (1) promotion of health care and planning at the national, divisional, local, and community levels, (2) promotion of medical services at all levels, and (3) effective decentralization of health services to enhance the services of health facilities.  相似文献   
49.
The incidence, distribution, time of appearance, and radiologic findings of bone metastases from soft tissue sarcomas, exclusive of lymphomas, were evaluated in 320 patients with soft tissue sarcomas. Thirty patients (9.4%) had evidence of 58 bone metastases. Five of 30 patients presented with metastases, and 25 of 30 patients developed metastases up to 66 months after presentation with a mean time interval of 21.3 months. The incidence of skeletal metastases differed among histologic subtypes of sarcomas; alveolar soft part sarcoma (5 of 8), dedifferentiated liposarcoma (2 of 4), angiosarcoma (2 of 4), and rhabdomyosarcoma (5 of 16) tended to show a higher incidence of bone metastases. The sarcomas metastasized to the regional bones close to the primary tumor in 16 (53%) of 30 patients and to the axial bones in 18 (60%). On conventional radiographs, the osseous metastases demonstrated predominantly osteolytic changes, and evidence of pathological fracture was observed in 31% of 58 metastases.  相似文献   
50.
To elucidate the necessity of pyloroplasty for the gastric tube through the posterior mediastinum in esophageal surgery, gastric emptying and duodenogastric reflux (DGR) were evaluated in 16 cases undergoing an anterior pylorectomy (group P) and in 16 cases treated by the finger bougie method (group F). First, the obstruction and reflux symptoms were examined based on a patient questionnaire using a brief scoring system. The median value of the symptom score showed the patients in P to have more symptoms than those in F; however, the difference was not significant (8.0 vs 6.0). Secondly, the swallowed Tc O4 (85 MBq) was counted using a gamma camera at three sites on the sternal bone in the upright position based on a gastric transit scintigram. Both the descending time of the RI peak and the clearance rates were similar between the two groups. Thirdly, intragastric 24-h pH monitoring was carried out. Antimony pH sensors were anchored 5 and 15 cm below the esophagogastrostomy. We could not find any difference between the two groups in both the % time pH>4 and %time pH>7. These findings thus revealed no big difference between groups P and F. The finger bougie method to drain the vagotomized posterior mediastinal stomach was found to achieve results similar to conventional pyloroplasty, while it was also simpler and safer.  相似文献   
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