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601.
AIMS: To evaluate the prevalence of congenital hypothyroidism (CH) in a screening program performed for the first time in Isfahan, Iran. METHODS: From May 2002 to December 2002, T4 and TSH serum concentrations of 20,000 3- to 7-day-old newborns, born in all 17 hospitals of the city, were measured by radioimmunoassay and immunoradiometric assay, respectively. The newborns with abnormal screening results (TSH >20 mIU/l, T4 <6.5 microg/dl and based on the weight) were re-examined. RESULTS: Of 531 recalled subjects (recall rate 2.6%), 54 were confirmed to be hypothyroid, showing a prevalence of 1:370 for CH. CONCLUSION: Considering the high frequency of CH, the necessity of implementing a routine screening program in the healthcare system of Isfahan Province is emphasized.  相似文献   
602.
Prekallikrein (PK) activation on human umbilical endothelial cells (HUVEC) presumably leads to bradykinin liberation. On HUVEC, PK activation requires the presence of cell-bound high-molecular-weight kininogen (HK) and Zn(2+). We examined the Zn(2+) requirement for HK binding to and the consequences of PK activation on endothelial cells. Optimal HK binding (14 pmol/10(6) HUVEC) is seen with no added Zn(2+) in HEPES-Tyrode buffer containing gelatin versus 16--32 microM added Zn(2+) in the same buffer containing bovine serum albumin. The affinity and number of HK binding sites on HUVEC are a dissociation constant of 9.6 +/- 1.8 nM and a maximal binding of 1.08 +/- 0.26 x 10(7) sites/cell (means +/- SD). PK is activated to kallikrein by an antipain-sensitive mechanism in the presence of HK and Zn(2+) on HUVEC, human microvascular endothelial cells, umbilical artery smooth muscle cells, and bovine pulmonary artery endothelial cells. Simultaneous with kallikrein formation, bradykinin (5.0 or 10.3 pmol/10(6) HUVEC in the absence or presence of lisinopril, respectively) is liberated from cell-bound HK. Liberated bradykinin stimulates the endothelial cell bradykinin B2 receptor to form nitric oxide. Assembly and activation of PK on endothelial cells modulates their physiological activities.  相似文献   
603.
Patients with pancreatic ductal adenocarcinomas (PDAC) have one of the poorest survival rates of all cancers. The main reason for this is related to the unique tumor stroma and poor vascularization of PDAC. As a consequence, chemotherapeutic drugs, such as nab-paclitaxel and gemcitabine, cannot efficiently penetrate into the tumor tissue. Non-invasive radiofrequency (RF) mild hyperthermia treatment was proposed as a synergistic therapy to enhance drug uptake into the tumor by increasing tumor vascular inflow and perfusion, thus, increasing the effect of chemotherapy. RF-induced hyperthermia is a safer and non-invasive technique of tumor heating compared to conventional contact heating procedures. In this study, we investigated the short- and long-term effects (~20 days and 65 days, respectively) of combination chemotherapy and RF hyperthermia in an orthotopic PDAC model in mice. The benefit of nab-paclitaxel and gemcitabine treatment was confirmed in mice; however, the effect of treatment was statistically insignificant in comparison to saline treated mice during long-term observation. The benefit of RF was minimal in the short-term and completely insignificant during long-term observation.  相似文献   
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Strawberry anthracnose, caused by Colletotrichum nymphaeae, is mainly controlled by the application of synthetic chemical fungicides. The present study assessed the antimicrobial activity of essential oils (EOs) from dill (Anethum graveolens L.) seed against C. nymphaeae. The antifungal effects of dill seed EO on C. nymphaeae was initially evaluated in vitro and further extended as in vivo condition. The results indicate that in the contact and volatile assays, dill seed EO significantly inhibited mycelial growth of C. nymphaeae at all concentrations tested. Conidia germination was also significantly inhibited at concentrations of 250 – 1000 ppm. Disease incidence and severity of anthracnose on strawberry fruits were significantly reduced compared with infected control, from concentrations of 500 and 50 ppm, respectively. The results confirm the efficacy of dill seed EO against C. nymphaeae, which may represent an alternative to synthetic chemical fungicides to control strawberry anthracnose pre- and post-harvest.  相似文献   
609.
Lead(II) nitrate complex with nicotinamide has been synthesized and characterized by elemental analysis, IR, 1H NMR, 13C NMR, UV-Vis spectroscopy and X-ray crystallography. The Pb2+ centres linked through nicotinamide and nitrate(V) ligands form a two-dimensional polymeric structure defining a double layer and each layer is also stabilized by hydrogen bonds of N-H?O and C-H?O type.  相似文献   
610.
To understand the complex nature of the atherogenic response initiated by oxidative stress in vascular smooth muscle cells (vSMCs), computational prediction methodology was employed to define putative gene-gene and gene-environment interactions in vSMCs subjected to oxidative chemical stress. Computational relationships were derived from the global gene expression profiles of murine cells challenged with a chemical pro-oxidant to cause oxidative stress or cells treated with anti-oxidant prior to oxidative injury. Target clones were chosen based on their biological relevance within the context of the atherogenic response and included lysyl oxidase, matrix metalloproteinase 2, insulin like growth factor binding protein 5, and lymphocyte antigen 6c. Established biological relationships were derived computationally confirming the usefulness of the algorithm in uncovering novel biological relationships worthy of future investigation. Thus, the predictive algorithm can be a useful tool to advance the frontiers of biological discovery.  相似文献   
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