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排序方式: 共有943条查询结果,搜索用时 15 毫秒
931.
932.
In the present study, we examined the efficacy of risperidone addition on sertraline-resistant depressed patients and the effects of risperidone on the metabolism of sertraline. Ten patients (M/F: 4/6, age: 54 +/- 10 years) met the DSM-IV criteria for major depressive disorder enrolled the study. Hamilton Dating Scale for Depression (HAM-D) scores (mean +/- SD) in all 10 patients significantly decreased from 19 +/- 4 (before risperidone addition) to 11 +/- 3 (4 weeks after risperidone addition). Plasma levels of sertraline and desmethylsertraline did not change after risperidone addition. Serum BDNF levels in responders to risperidone addition were changed from 8.1 +/- 2.7 ng/ml (before risperidone addition) to 11.5 +/- 0.9 ng/ml (4 weeks after risperidone addition); in contrast, those in nonresponders changed from 7.8 +/- 2.2 ng/ml (before risperidone addition) to 7.9 +/- 2.4 ng/ml (4 weeks after risperidone addition). These results suggest that the addition of risperidone to sertraline is effective and well tolerated for sertraline-resistant depressive patients, which is accompanied with the increase in serum BDNF levels in responders to the risperidone addition, and the addition of risperidone to sertraline does not seem to influence sertraline metabolism.  相似文献   
933.
934.
A case of Behçet's disease (BD) with occlusion of both caval veins and “downhill” esophageal varices is reported. A 59-year-old male patient had esophageal varices, established as the “downhill” type by endoscopy, venography, and contrast-enhanced computed tomography (CE-CT) scan. Venography via both jugular veins did not lead to the visualization of the superior vena cava (SVC), but revealed numerous collateral veins, which formed esophageal varices en route. Venography via both femoral veins did not lead to the visualization of the inferior vena cava (IVC), but revealed numerous collateral veins, which flowed into the portal vein together with the jugular flow. CE-CT scan revealed the disappearance of the SVC and the lower part of the IVC, below the hepatic vein. The patient was diagnosed as having BD, based on his history of recurrent oral and skin lesions over the past 26 years.  相似文献   
935.
We report a case of an anti-nuclear antibody (ANA)-negative patient with systemic lupus erythematosus (SLE) accompanied with anti-phospholipid antibody syndrome (APS) and lupus nephritis (LN). Histological examination of placenta obtained by an artificially-induced abortion revealed multiple thromboses in the placental villi. Histology of biopsied kidney tissue revealed minimal change with deposits of immunoglobulin and complement. Anti-ribosomal P antibodies (anti-P) and lupus anticoagulant (LAC) were positive and anti-double stranded DNA antibody (anti-DNA) showed only a slightly positive titer in her serum. The intensity of proteinuria of the patient was correlated with the anti-P, but not anti-DNA titers.  相似文献   
936.
The ability of human deciduous tooth dental pulp cells (HDDPCs) to differentiate into odontoblasts that generate mineralized tissue holds immense potential for therapeutic use in the field of tooth regenerative medicine. Realization of this potential depends on efficient and optimized protocols for the genetic manipulation of HDDPCs. In this study, we demonstrate the use of a PiggyBac (PB)-based gene transfer system as a method for introducing nonviral transposon DNA into HDDPCs and HDDPC-derived inducible pluripotent stem cells. The transfection efficiency of the PB-based system was significantly greater than previously reported for electroporation-based transfection of plasmid DNA. Using the neomycin resistance gene as a selection marker, HDDPCs were stably transfected at a rate nearly 40-fold higher than that achieved using conventional methods. Using this system, it was also possible to introduce two constructs simultaneously into a single cell. The resulting stable transfectants, expressing tdTomato and enhanced green fluorescent protein, exhibited both red and green fluorescence. The established cell line did not lose the acquired phenotype over three months of culture. Based on our results, we concluded that PB is superior to currently available methods for introducing plasmid DNA into HDDPCs. There may be significant challenges in the direct clinical application of this method for human dental tissue engineering due to safety risks and ethical concerns. However, the high level of transfection achieved with PB may have significant advantages in basic scientific research for dental tissue engineering applications, such as functional studies of genes and proteins. Furthermore, it is a useful tool for the isolation of genetically engineered HDDPC-derived stem cells for studies in tooth regenerative medicine.  相似文献   
937.
The asialoglycoprotein receptor (AGPR) is responsible for the catabolism of acute phase proteins. The effects of inflammation-related cytokines on the expression of AGPR were investigated in HepG2 cells derived from a human hepatoblastoma cell line. Binding studies, using a [125I]-labeled asialo-orosomucoid ligand, revealed that AGPR numbers on cell surfaces were increased by interleukin-1 (IL-1), interleukin-6 (IL-6), and tumor necrosis factor (TNF). In cells treated with IL-1, IL-6, or TNF, immunohistochemical staining with an anti-AGPR monoclonal antibody demonstrated augmented expression. Pulse labeling analysis, using [35S]-labeled methionine, showed newly synthesized AGPR in both the precursor and the mature forms. When IL-1, IL-6, and TNF were added to the culture medium, total synthesis of AGPR (sum of the mature and precursor forms) was increased. In addition, the relative proportion of the synthesized precursor form of AGPR was higher in cytokine-treated than in untreated cells, suggesting that these cytokines augment the synthesis of AGPR, particularly in the stage prior to glycosylation.  相似文献   
938.
Autoimmune hepatitis overlapping with primary sclerosing cholangitis   总被引:2,自引:0,他引:2  
A case of autoimmune hepatitis (AIH) complicated by primary sclerosing cholangitis (PSC) in a 36-year-old woman is reported. AIH overlapping with PSC has been rarely reported, and to the best of our knowledge, there have been no reports in Japan. Based on the criteria for diagnosis of AIH and on typical endoscopic retrograde cholangiograph (ERC) findings, the patient was diagnosed as having AIH overlapping with PSC. Her transaminase levels normalized within 1 month after administration of prednisone, azathioprine and ursodeoxycholic acid, but her cholestatic enzyme level remained elevated. The effect of treatment on the cholestatic features is thought to be an important factor for predicting the prognosis of AIH overlapping with PSC.  相似文献   
939.
Aim: Activated hepatic stellate cells (HSC) play a critical role in liver fibrosis. Suppressing abnormal function of HSC or reversion from activated to quiescent form is a hopeful treatment for liver cirrhosis. The interaction between platelets and HSC remains unknown although platelets go through hepatic sinusoids surrounded by HSC. This study aimed at clarifying the hypothesis that platelets control activation of HSC. Methods: We used human platelets, platelet extracts, and primary or immortalized human HSC. We examined the effect of platelets on the activation, DNA synthesis, type I collagen production, and fibrosis-relating gene expressions of HSC. We investigated what suppressed activation of HSC within platelets and examined the mechanism of controlling activation in vitro. Results: Platelets and platelet extracts suppressed activation of HSC. Platelets decreased type I collagen production without affecting DNA synthesis. Platelets increased the expression of matrix metallopeptidase 1. As platelet extracts co-cultured with an enzyme of degrading adenosine 5'-triphosphate (ATP) suppressed activation, we detected adenine nucleotides within platelets or on their surfaces and confirmed the degradation of adenine nucleotides by HSC and the production of adenosine. Adenosine and platelets increased the intracellular cyclic adenosine 5'-monophosphate (cAMP), which is important in quiescent HSC. A great amount of adenosine and ATP also suppressed activation of HSC. Conclusion: Activation of human HSC is suppressed by human platelets or platelet-derived ATP via adenosine-cAMP signaling pathway in vitro. Therefore, platelets have the possibility to be used in the treatment of liver cirrhosis.  相似文献   
940.
Esophageal squamous cell carcinomas (ESCCs) as well as adenocarcinomas (EACs) were developed in rat duodenal contents reflux models (reflux model). The present study aimed to shed light on the mechanism by which bile acid stimulation causes cancer onset and progression. Metabolomics analyses were performed on samples of neoplastic and nonneoplastic tissues from reflux models, and K14D, cultivated from a nonmetastatic, primary ESCC, and ESCC‐DR, established from a metastatic thoracic lesion. ESCC‐DRtca2M was prepared by treating ESCC‐DR cells with taurocholic acid (TCA) to accelerate cancer progression. The lines were subjected to comprehensive genomic analyses. In addition , protein expression levels of glucose‐6‐phosphate dehydrogenase (G6PD), nuclear factor kappa B (NF‐κB) (p65) and O‐linked N‐Acetylglucosamine (O‐GlcNAc) were compared among lines. Cancers developed in the reflux models exhibited greater hexosamine biosynthesis pathway (HBP) activation compared with the nonneoplastic tissues. Expression of O‐GlcNAc transferase (OGT) increased considerably in both ESCC and EAC compared with nonneoplastic squamous epithelium. Conversely, cell line‐based experiments revealed the greater activation of the pentose phosphate pathway (PPP) at higher degrees of malignancy. G6PD overexpression in response to TCA exposure was observed. Both NF‐κB (p65) and O‐GlcNAc were expressed more highly in ESCC‐DRtca2M than in the other cell lines. Moreover, ESCC‐DRtca2M cells had additional chromosomal abnormalities in excess of ESCC‐DR cells. Overall, glucose metabolism was upregulated in both esophageal cancer tissue and cell lines. While bile acids are not mutagenic, chronic exposure seems to trigger NF‐κB(p65) activation, potentially inducing genetic mutations as well as facilitating carcinogenesis and cancer progression. Glucose metabolism was upregulated in both esophageal cancer tissue and cell lines, and the HBP was activated in the former. The cell line‐based experiments demonstrated upregulation of the pentose phosphate pathway (PPP) at higher degrees of malignancy. While bile acids are not mutagenic, chronic exposure seems to trigger G6PD overexpression and NF‐κB (p65) activation, potentially inducing genetic mutations as well as facilitating carcinogenesis and cancer progression.  相似文献   
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