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1.
Some biochemical and enzymatic constituents were determined in the small intestinal tract tissues of normal and sodium glycollate treated adult male rats. Alterations were observed with respect to certain lipids and carbohydrate fractions in the glycollate fed rats. DNA content was also elevated in this group. The functions of the cell membrane is likely to be affected as reflected in the levels of transport ATPases and orthophospho-hydrolases. The activities of the two marker enzymes in the intestinal brush border, namely alkaline phosphatase and leucylnaphthylamidase were reduced in the glycollate administered group. Administration of L(+)-tartrate, which is a mild laxative and has a regulatory influence on oxalate metabolism, lowered the activities of Na+, K(+)- and Ca(2+)-ATPases. There was a distinct lowering in the level of acid phosphatase in the tartrate treated rats. 相似文献
2.
Rajan KN Selvam TP Bhatt BC Vijayam M Patki VS Vinatha Pendse AM Kannan V 《Physics in medicine and biology》2002,47(7):1047-1058
The primary standard of low air kerma rate sources or beams, maintained at the Radiological Standards Laboratory (RSL) of the Bhabha Atomic Research Centre (BARC), is a 60 cm3 spherical graphite ionization chamber. A 192Ir HDR source was standardized at the hospital site in units of air kerma strength (AKS) using this primary standard. A 400 cm3 bakelite chamber, functioning as a reference standard at the RSL for a long period, at low air kerma rates (compared to external beam dose rates), was calibrated against the primary standard. It was seen that the primary standard and the reference standard, both being of low Z, showed roughly the same scatter response and yielded the same calibration factor for the 400 cm3 reference chamber, with or without room scatter. However, any likelihood of change in the reference chamber calibration factor would necessitate the re-transport of the primary standard to the hospital site for re-calibration. Frequent transport of the primary standard can affect the long-term stability of the primary standard, due to its movement or other extraneous causes. The calibration of the reference standard against the primary standard at the RSL, for an industrial type 192Ir source maintained at the laboratory, showed excellent agreement with the hospital calibration, making it possible to check the reference chamber calibration at RSL itself. Further calibration procedures have been developed to offer traceable calibration of the hospital well ionization chambers. 相似文献
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Varicocele is one of the major causes of male infertility and has a negative impact on spermatogenesis. The conventional semen analysis does not reveal the underlying subcellular mechanisms associated with defects in spermatozoa. Proteomics and bioinformatics analysis can be used to identify the molecular aetiologies associated with poor semen quality in varicocele patients. Mitochondrial dysfunction has been identified as the main factor affecting normal physiological functions of spermatozoa. This article discusses the proteomic studies of spermatozoa and seminal plasma in varicocele patients. Proteomics can identify potential spermatozoa and seminal plasma biomarkers in varicocele-mediated male infertility. In future, these protein biomarkers can be useful in the development of noninvasive diagnostic and therapeutic strategies for varicocele patients. 相似文献
5.
Jeffrey D Bradley Farrokh Dehdashti Mark A Mintun Ramaswamy Govindan Kim Trinkaus Barry A Siegel 《Journal of clinical oncology》2004,22(16):3248-3254
PURPOSE: To determine how often positron emission tomography with [(18)F]fluoro-2-deoxy-D-glucose (FDG-PET) detects extensive-stage small-cell lung cancer (SCLC) in patients considered to have limited-stage disease based on conventional staging procedures, and to determine the impact of PET on treatment planning for presumed limited-stage SCLC. PATIENTS AND METHODS: We prospectively performed pretreatment FDG-PET on 24 patients determined by conventional staging methods to have limited-stage SCLC (defined as disease that could be encompassed within a reasonable radiotherapy portal, excluding bilateral supraclavicular disease). PET images were evaluated for evidence of extensive-stage disease. Tumor-node-metastasis system staging was also assigned for each patient, with and without PET information. RESULTS: FDG-PET demonstrated findings consistent with extensive-stage SCLC in three of 24 patients. FDG-PET correctly upstaged two (8.3%) of 24 patients to extensive-stage disease (95% CI, 1.03% to 27.0%). PET correctly identified tumor in each SCLC mass (primary or nodal) that was suspected on computed tomography (CT) imaging, thus giving a lesion-based sensitivity relative to CT of 100%. PET identified unsuspected regional nodal metastasis in six (25%) of 24 patients, and the radiation therapy plan was significantly altered to include the PET-positive/CT-negative nodes within the high-dose region in each of these patients. Brain PET images in 23 patients disclosed no evidence of brain metastasis. CONCLUSION: FDG-PET has high sensitivity for SCLC and appears to be of value for initial staging and treatment planning of patients with presumed limited-stage disease. 相似文献
6.
Veerappan Muthuviveganandavel Inho Hwang Vanattayen Anita Pattabiraman S. Malarani Chandrasekar Selvam Moorthy Hemalatha Muthuraman Pandurangan 《International journal of experimental pathology》2013,94(2):104-108
Alpha‐cypermethrin is an isoform of cypermethrin; it is an active pyrethroid used extensively to control a wide range of pests in agriculture and animal breeding. In this study four groups of six fish were examined. The first group served as a control in fresh water alone, with no pyrethroid. The second, third and fourth groups were exposed to alpha‐cypermethrin for 4, 8 and 96 h respectively. At the end of the each exposure period, the fish were sacrificed, and the required muscle tissues were collected for histological examination. The blood was drawn with heparinized needles and processed for serum enzymatic studies. Serum enzymes such as aspartate transaminase (AST), alanine transaminase (ALT), amylase, acid phosphatase (ACP) and gamma‐glutamyl transpeptidase (GGT) were measured at 4, 8 and 96 h. AST enzyme activity was significantly increased at 4 h, whereas ALT and amylase enzyme activities were significantly reduced at all the time points. ACP enzyme activity was significantly reduced at 4 and 8 h, whereas GGT enzyme activity was significantly increased at all the time points. Hepatocyte cytoplasmic vacuolisation and degeneration, rupture of blood vessels, and necrosis was found at all time points. Congestion of blood vessels, bulging, distortion of filaments, erosion and disintegration of blood corpuscles and hyperplasia of epithelium were found in treated gills at 4, 8 and 96 h. Breakdown of muscle fibres, vacuolation and accumulation of lipids and melanin in white muscle were observed in treated fish muscle at 4, 8 and 96 h. 相似文献
7.
The preterm very low birth weight infants are at high risk of developing neurodevelopmental delay despite little or no medical complications at the time of birth. The care and interventions of such infants have an impact on the pre-existing risk. The Developmental Care Interventions (DCI) are the range of treatment strategies aiming to alleviate the risk thereby improving neuro-developmental outcomes. The objective of this review is to appraise the range of such interventions for preterm very low birth weight infants reported in the literature. This review will help clinicians to adopt developmental intervention strategy to improve the neuro-developmental outcomes of their NICU graduates. 相似文献
8.
Hui Yu Zhengming Chen Karla V. Ballman Mark A. Watson Ramaswamy Govindan Irena Lanc David G. Beer Raphael Bueno Lucian R. Chirieac Michael Herman Chui Guoan Chen Wilbur A. Franklin David R. Gandara Carlo Genova Kristine A. Brovsky Mary-Beth M. Joshi Daniel T. Merrick William G. Richards Fred R. Hirsch 《Journal of thoracic oncology》2019,14(1):25-36
Objectives
Anti–programmed cell death 1 (PD-1)/programmed death ligand 1 (PD-L1) immunotherapy has demonstrated success in the treatment of advanced NSCLC. Recently, PD-1/PD-L1 blockade also has demonstrated interesting results in small trials of neoadjuvant treatment in stage IB to IIIA NSCLC. In addition, several clinical trials using anti–PD-1/PD-L1 immunotherapy as an adjuvant or neoadjuvant treatment in patients with resectable stage NSCLC are ongoing. However, few analyses of anti–PD-1/PD-L1 immunotherapy–related biomarkers in early-stage squamous cell lung carcinoma (SqCLC) have been reported. In this study, we evaluated PD-L1 protein expression, tumor mutation burden, and expression of an immune gene signature in early-stage SqCLC, providing data for identifying the potential role for patients with anti–PD-1/PD-L1 treatment in early-stage SqCLC.Methods
A total of 255 specimens from patients with early-stage SqCLC were identified within participating centers of the Strategic Partnering to Evaluate Cancer Signatures program. PD-L1 protein expression by immunohistochemistry was evaluated by using the Dako PD-L1 22C3 pharmDx kit on the Dako Link 48 auto-stainer (Dako, Carpinteria, CA). Tumor mutation burden (TMB) was calculated on the basis of data from targeted genome sequencing. The T-effector and interferon gamma (IFN-γ) gene signature was determined from Affymetrix gene chip data (Affymetrix, Santa Clara, CA) from frozen specimens.Results
The prevalence of PD-L1 expression was 9.8% at a tumor proportion score cutoff of at least 50%. PD-L1 mRNA and programmed cell death 1 ligand 2 mRNA positively correlated with PD-L1 protein expression on tumor cells (TCs) and tumor-infiltrating immune cells. PD-L1 protein expression on tumor-infiltrating immune cells was correlated with the T-effector and IFN-γ gene signature (p < 0.001), but not with TMB. For TCs, all of these biomarkers were independent of each other and neither PD-L1 protein expression, TMB, or T-effector and IFN-γ gene signatures were independently prognostic for patient outcomes.Conclusions
Evaluation of PD-L1 expression, TMB, and T-effector and IFN-γ gene signatures in the cohort with early-stage SqCLC found them to be independent of each other, and none was associated with overall survival. Our results also support the hypothesis that PD-L1 expression is regulated by an intrinsic mechanism on TCs and an adaptive mechanism on immune cells. 相似文献9.
10.