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Many synthesized semiconductor QDs materials are formed using trioctylphosphine oxide (TOPO) but it requires high temperature, is very expensive and is also hydrophobic. Our study deals with selective syntheses of CdSe and core–shell CdSe/ZnS quantum dots (QDs) in aqueous solution by a simple heating and refluxing method. It is more hydrophilic, needs less temperature, is economically viable and is eco-friendly. Bio-ligands, such as thioacetamide, itaconic acid and glutathione, were used as stabilizers for the biosynthesis of QDs. A simplified aqueous route was used to improve the quality of the colloidal nanocrystals. As a result, highly monodisperse, photoluminescent and biocompatible nanoparticles were obtained. The synthesized QDs were characterized by XRD, FTIR, confocal microscopy, ultraviolet (UV) absorption and photoluminescence (PL). The size of synthesized QDs was observed as 5.74 nm and the core–shell shape was confirmed by using XRD and confocal microscopy respectively. The QD nanoparticles showed antibacterial activity against pathogenic bacteria. The QDs could be applied for biological labelling, fluorescence bio-sensing and bio-imaging etc.

Mystristic capped CdSe QDs with schematic diagram and formation mechanism of bio-taggable CdSe@ZnS QDs.  相似文献   
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The present study is designed to evaluate the efficacy of heptoplus a polyherbal formulation as an oral supplementary agent for isoniazid and rifampicin induced hepatotoxicity in rats. 50 and 100 mg/kg of heptoplus supplement were fed orally to the rats along with isoniazid and rifampicin and compared to rats treated with 100 mg/kg Liv 52 standard drug. Rats treated with isoniazid and rifampicin suffered from severe oxidative stress by the virtue of free radicals induced lipid per oxidation. As a result abnormal index of serum biochemical markers for liver function and increased liver lysosomal enzymes activity was observed. However rats nourished with 100 mg/kg of heptoplus and Liv 52 protected the liver from oxidative damage by maintaining normal antioxidant profile status and restored normal serum liver biochemical markers. Increased liver lysosomal enzymes activity is prevented in the rats supplemented with heptoplus and Liv 52. Histopathological analysis also revealed severe vascular changes and lobular necrosis in the treatment of isoniazid and rifampicin. Heptoplus (100 mg/kg) and Liv 52 supplemented rats liver apparently revealed normal architecture of liver. This study confirms that heptoplus has liver protective activity against Isoniazid and Rifampicin induced liver injury in rats, in par with Liv 52.  相似文献   
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The present studies were carried out to compare the low density lipoprotein (LDL) metabolism by freshly isolated immature porcine granulosa cells with that by luteal cells. Furthermore, we have examined the effect of serum used for plating of granulosa cells on lipoprotein degradation and utilization. In incubation studies, addition of LDL as an exogenous substrate had a mild stimulatory effect on progesterone accumulation by granulosa cells, while it exhibited a dose-dependent stimulatory effect on luteal cells. When granulosa and luteal cells were incubated with 125I-labelled LDL, membrane binding of LDL occurred in both cell types, but only luteal cells were capable of internalizing the bound LDL. Granulosa cells in incubation degraded LDL much less in comparison with luteal cells, and the amount varied with the maturity of the cells. When granulosa cells were plated with graded amounts of serum which was withdrawn for 48 h following plating, they exhibited enhanced LDL degradation in a serum concentration-dependent fashion. Addition of serum for plating selectively enhanced utilization of LDL, but not high density lipoprotein (HDL) for progesterone accumulation by the cells in culture. Time-course studies on LDL degradation by granulosa cells following serum withdrawal indicate that the ability of cells to degrade LDL decreased in a time-dependent fashion. Serum withdrawal selectively decreased utilization of LDL but not HDL for progesterone secretion. It is concluded that immature granulosa cells have a limited capability to utilize cholesterol carried by LDL.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
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A third of patients with multiple myeloma (MM) have a preceding diagnosis of plasma cell proliferative disorder (PCPD), mostly monoclonal gammopathy of undetermined significance (MGUS), smoldering MM (SMM) or plasmacytoma. While autologous stem cell transplantation (SCT) improves survival in MM, it is not clear if patients with preceding PCPD have a different outcome. We identified 151 patients with preceding PCPD from among 804 patients undergoing SCT, and their outcomes were compared. The response rates, including complete responses, were similar between the groups. Patients with a preceding diagnosis of MGUS had longer time to progression (TTP; 27·5 months vs. 17·2 months, P  = 0·01), and longer overall survival (OS) from transplant (80·2 months vs. 48·3 months, P  = 0·03) compared to those with de novo myeloma. However no differences were seen among those with a preceding diagnosis of SMM or plasmacytoma in terms of TTP or OS from transplant when compared to those with de novo myeloma. Multivariate analysis indicated that the presence of MGUS prior to myeloma was prognostic for post-transplant relapse independent of other known risk factors. Patients with pre-existing MGUS prior to myeloma diagnosis have a better outcome following HDT, reflecting more indolent disease and a favourable biology than those presenting with de novo myeloma.  相似文献   
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Muscle infaction is a rare complication in patients with diabetes mellitus, probably because of the rich vascular supply of this tissue. We describe a patient with type 1 diabetes who had infarction of the muscles in her right thigh. We report, for the first time, that the patient, in addition to an advanced microvascular disease in the muscle, had increased plasma total homocysteine levels and increased platelet aggregation. These pathologies might have a synergistic effect on the development of this rare complication and should be treated aggrssively to prevent further episodes.  相似文献   
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A 48-eight-year-old female patient came with prolapse of small intestines per rectum (Fig. 1) due to impalement injury with iron rod at a construction site. As the patient was hemodynamically unstable, she was taken for emergency laparotomy. A large rent in the intraperitoneal rectum was found (Fig. 2), with prolapse of intestines. Luckily for the patient, there was no other intra-abdominal organ injury. As there was no fecal contamination at all, a decision against proximal colostomy was made. The rent was closed in two layers after re-placing the small bowel contents with thorough lavage. Patient made a swift recovery thereafter.Open in a separate windowFig. 1Patient presented with prolapse of bowel contents per rectum due to injuryOpen in a separate windowFig. 2Intraoperative picture showing the perforation involving the rectum  相似文献   
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Bortezomib, a potent and reversible proteasome inhibitor, affects the myeloma cell and its microenvironment, resulting in down-regulation of growth and survival signaling pathways and durable responses in patients with relapsed and refractory myeloma. Potential associations between baseline parameters and outcomes with bortezomib were explored in 202 patients who received bortezomib 1.3 mg/m2 twice weekly for 2 weeks every 3 weeks for up to 8 cycles in a phase 2 trial. Using European Group for Blood and Marrow Transplantation criteria, the response rate (complete or partial response) to bortezomib alone was 27% and was not associated with sex, race, performance status, isotype, chromosome 13 deletion, number or type of previous therapies, or concentration of hemoglobin or beta2-microglobulin. By multivariate analysis, factors associated with lower response were being age 65 or older versus younger than 65 (19% vs 32%; P < .05) and plasma-cell infiltration in bone marrow greater than 50% versus 50% or less (20% vs 35%; P < .05). Factors that may be indicative of tumor burden (bone marrow plasma-cell infiltration greater than 50%, hypoalbuminemia, thrombocytopenia) were predictive of overall survival. Chromosome 13 deletion and elevated beta2-microglobulin, generally considered poor prognostic factors, were not predictive of poor outcome with bortezomib in this study.  相似文献   
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