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461.
Polystyrene-silica core-shell nanocomposite particles are successfully prepared via one-step Pickering emulsion polymerization. Possible mechanisms of Pickering emulsion polymerization are addressed in the synthesis of polystyrene-silica nanocomposite particles using 2,2-azobis(2-methyl-N-(2-hydroxyethyl)propionamide (VA-086) and potassium persulfate (KPS) as the initiator. Motivated by potential applications of “smart” composite particles in controlled drug delivery, the one-step Pickering emulsion polymerization route is further applied to synthesize polystyrene/poly(N-isopropylacrylamide) (PNIPAAm)-silica core-shell nanoparticles with N-isopropylacrylamide incorporated into the core as a co-monomer. The polystyrene/PNIPAAm-silica composite nanoparticles are temperature sensitive and can be taken up by human prostate cancer (PC3-PSMA) cells.  相似文献   
462.
Metaphase (M‐) and array (A‐) Comparative Genomic Hybridization (CGH) were used to investigate 40 cases of T‐ and 32 of B‐cell acute lymphoblastic leukaemia (ALL) with normal/failed cytogenetics. M‐CGH was performed in all cases and A–CGH in 10/12 T‐ALL cases with uncertain/normal M‐CGH results. M‐CGH was abnormal in 38/72 cases, with a total of 110 imbalances (60 gains, 50 losses). 25/40 patients with T‐ALL (62·5%) showed 77 imbalances, with at least 1 genomic imbalance and a mean of 3 aberrations/patient (range 1–12). 13/32 patients with B‐ALL (40·6%) presented 34 imbalances, with a mean of 2·6 imbalances (range 1–8). A‐CGH detected 4 more T‐ALL cases with genomic imbalances. A‐CGH identified NF1/17q11·2 deletion and interphase fluorescence in situ hybridization provided a 10·8% estimated overall incidence of NF1/17q11·2 deletion in T‐ALL. In all but one case (6/7) with NF1 deletion, denaturing high‐performance liquid chromatography and direct sequencing detected NOTCH1 gene mutations. Three or more imbalances in CGH‐positive cases were significantly associated with resistance to treatment and death during or after induction therapy. We suggest that the work‐up for ALL at diagnosis should include CGH investigations, particularly when cytogenetics is uninformative, because they may provide potentially valuable information with prognostic and therapeutic implications.  相似文献   
463.
To assess the effect of age on response and compliance to treatment in patients with chronic myeloid leukemia (CML) we performed a sub-analysis within a phase II trial of the GIMEMA CML Working Party (CML/002/STI571). Since the WHO cut-off age to define an older patient is 65 years, among the 284 patients considered, we identified 226 (80%) younger patients (below 65 years) and 58 (20%) older patients (above 65 years) before starting imatinib. Response rates (hematologic and cytogenetic) were lower in the older age group but the probabilities of progression-free survival and overall survival (median observation time 3 years) were the same. Moreover, among complete cytogenetic responders, no differences were found in the level of molecular response between the two age groups. As might be expected, older patients experienced more adverse events, both hematologic and non-hematologic: this worsened compliance did not, however, prevent a long-term outcome similar to that of younger patients.  相似文献   
464.
Diagnosis of hepatocellular carcinoma (HCC) is not always easy on simple hematoxylin and eosin (H&E) stain. The diagnostic problems arise when tumor shows pseudoglandular, pleomorphic or clear cell differentiation. Various tumors markers have been described with varying sensitivity and specificity. Monoclonal antibody Hep Par 1 (OCH1E5) which is specific for hepatocytes offers great help in separation of these tumors. The aim of the present study was to determine utility of Hep Par 1 (OCH1E5) in differentiating HCC from metastatic tumors and cholangiocarcinoma. Total of 62 cases of liver tumors obtained from biopsies, resected or autopsy specimens were included in the study. Slides having representative sections were subjected to immunohistochemistry with monoclonal antibody Hep Par 1 (Dako Corp) using avidin biotin technique with primary antibody dilution of 1:40. Adjacent nontumorous hepatocytes were taken as positive control. Slides were examined by experienced pathologist without any information of clinical or H&E diagnosis. Cases were considered positive for Hep Par 1 if tumor cells showed cytoplasmic brown colored granules. The intensity and distribution (diffuse/ focal) of immunoreactivity was noted. Subsequently immunohistochemistry results were correlated with histology and clinical diagnosis. Hep Par 1 antibody was positive in 26 (42 %) and negative in 36 (58 %) liver tumors. On correlating with H&E sections, out of 26 positive cases, 25 (89.2%) were HCC and one was the case of metastasis of mucin secreting adenocarcinoma. From 36 tumors with negative staining 3 were cases of HCC, 27 metastatic adenocarcinomas and 6 cholangiocarcinomas. Only one case of liver metastasis of mucin secreting adenocarcinoma showed positivity. None of the cases of cholangiocarcinoma showed positivity for Hep Par 1. The three HCCs which did not take up staining for Hep Par 1 were 2 cases of moderately differentiated HCC having pseudoglandular pattern and a case of well differentiated HCC with trabecular arrangement. In 11(44%) cases staining was diffuse while in 14 (56%) it was focal but intense. Hep Par 1 is a useful marker in differentiating HCC from metastaic tumors and cholangiocarcinoma with sensitivity and specificity of 89 % and 97 % respectively and positive predictive value of 96 %. However one should be aware of limitations of immunohistochemistry.  相似文献   
465.
Experimental studies conducted earlier have proved that Phyllanthus emblica (Pe), Plumbago zeylanica (Pz) and Cyperus rotundus (Cr), plants from the medohara group of Ayurveda possess antiatherosclerotic activity. As inflammation is also one of the pathophysiological factors, it was of interest to evaluate whether these drugs exhibit any antiinflammatory activity. Two models of acute inflammation, namely carrageenan induced rat paw edema and acetic acid induced peritonitis in mice were used. In the model of carrageenan induced paw edema Pe, Pz and Cr showed a trend to reduce the edema while the combination of Pe + Pz (PI: 20.64%) showed results comparable to aspirin (23.74%). Whereas in a model of acetic acid induced peritonitis, all the plant drugs i.e. Pe, Pz, Cr and a combination of Pe + Pz showed a significant decrease in the protein content of the peritoneal exudates compared with the disease control group (p < 0.05), however, only Pe + Pz exhibited activity comparable to aspirin.  相似文献   
466.
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468.
The aim of the present paper was to describe the mechanisms and management of antipsychotic-induced weight gain in schizophrenia patients. A comprehensive literature review of all available articles on the mechanisms and management of antipsychotic-induced weight gain was done by searching databases PsychINFO and PubMed. A summary of the available guidelines for monitoring of antipsychotic-induced weight gain and metabolic syndrome is also provided. There has been a substantial increase in the number of studies investigating the mechanisms and management of antipsychotic-induced weight gain after 2002. These include advances in the understanding of pharmacogenomics of weight gain and several randomized controlled trials (RCTs) evaluating pharmacological and psychological treatments to promote weight loss. The most effective strategy for prevention of weight gain is the choice of antipsychotic medication with low weight gain potential. In individuals with established weight gain and metabolic issues, switching to an antipsychotic agent with lower weight gain potential and/or lifestyle modifications with physical activity are most effective in promoting weight loss. Pharmacological agents such as orlistat and sibutramine are effective in general obesity but have not been sufficiently evaluated in antipsychotic-induced weight gain. The case to prescribe routine pharmacological treatment to promote weight loss is weak. Long-term, pragmatic studies are required to inform clinical practice. Weight gain in schizophrenia is associated with significant physical and psychological morbidity. Achieving an optimal trade-off between effectiveness and side-effects of antipsychotic agents, although difficult, is achievable. This should be based on three main principles: (i) a shared decision-making model between the patient, clinician and carer(s) when choosing an antipsychotic; (ii) a commitment to baseline and follow-up monitoring with explicit identification of the responsible individual or team; and (iii) the adoption of clear structured protocols for clinicians to follow in case of clinically significant weight gain and metabolic issues, which should incorporate greater collaboration between various health professionals from psychiatric and medical specialist services.  相似文献   
469.
470.
Abstract Background: Classic risk factors for candidemia include use of total parenteral nutrition (TPN), hospital location, use of central venous catheter, and others. Unfortunately, most of these variables are now also risk factors for antibiotic-resistant bacteria. Thus, use of these risk factors to identify patients at high risk for candidemia is difficult. The purpose of this study was to compare these classic risk factors for candidemia in patients with bloodstream infections to determine the relative strength of these predictors in differentiating patients with candidemia and bacteremia. Methods: Clinical data were collected from the medical charts of patients who had been hospitalized between 2002 and 2004. Patients with their first episode of candidemia or bacteremia during their hospital stays were included. Risk factors were assessed using a multivariate logistic regression model and internally validated using a bootstrap analysis. A p-value < 0.05 was considered significant. Results: A total of 164 patients (82 with candidemia) were evaluated. According to the logistic analysis, patients who had stayed in the intensive care unit (ICU) (OR = 6.24; 95% CI: 2.58–15.09) or had been using TPN (OR = 4.69; 95% CI: 1.76–12.48) were more likely to have candidemia than bacteremia. While patients with pulmonary (OR = 0.15; 95% CI: 0.055–0.39) or cardiac disease (OR = 0.21; 95% CI: 0.086–0.51) had a greater chance to have bacteremia than candidemia (p < 0.01 for all variables). These results were further validated using bootstrap analysis. Conclusion: Among classic risk factors for candidemia, the ICU location at the time of culture and TPN use were most predictive of candidemia while certain medical disorders predicted patients at the highest risk for bacteremia. These results can be used to help identify patients most likely to benefit from empiric antifungal therapy. This paper was presented in part at the 10th annual meeting of the International Society for Pharmacoeconomics and Outcomes Research (ISPOR), Washington, DC, USA, on May 17th, 2005.  相似文献   
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