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991.
992.
Comparison of total phosphorus and chlorophyll-a concentration, nutrient loading, and water turn-over time in six shallow choked lagoons along the coast of the state of Rio de Janeiro, Brazil, established that water turn-over time is related to the trophic state of the lagoons with additional anthropogenic nutrient loading affecting this relationship. Turnover time was calculated as a flushing half-life from rainfall, evaporation, runoff, and tidal exchange data, and trophic state was calculated from the quantity and quality of dissolved inorganic nutrients, total phosphorus, and chlorophyll-a standing stock. Flushing half-life of the lagoons ranged between 1 and 27 days, annual phosphorus areal loading from 3 to 18 mg m–2d–1, and chlorophyll-a standing stock from 6 to 160 mg M–2  相似文献   
993.
Breast involvement by lymphoma is uncommon and poses challenges in diagnosis. Lymphomas may clinically, radiologically, and morphologically mimic both benign and neoplastic conditions. We describe two cases of lymphoid malignancies predominantly involving the breast, both presenting diagnostic dilemmas. The first case, ALK-negative anaplastic large-cell lymphoma involving a seroma associated with a breast implant, is an emerging clinicopathologic entity. Anaplastic large-cell lymphoma has been identified in association with breast implants and seroma formation relatively recently. The second case, hairy cell leukemia involving the breast and ipsilateral axillary sentinel lymph node, is, to our knowledge, the first reported case of hairy cell leukemia involving the breast at the time of diagnosis. While a localized bone lesion was present at time of diagnosis, bone marrow involvement was relatively mild in comparison to that seen in the breast and lymph node. In the first case, lymphoma occurred in a clinical setting where malignancy was unsuspected, highlighting the importance of careful morphologic evaluation of paucicellular samples, as well as awareness of rare clinicopathologic entities, in avoiding a misdiagnosis of a benign inflammatory infiltrate. In the second case, the lymphoid neoplasm exhibited classic morphologic and immunophenotypic features, but presented at an unusual site of involvement. Knowledge of the patient''s concurrent diagnosis of hairy cell leukemia involving the bone marrow and bone helped avoid a misdiagnosis of carcinoma rather than lymphoma.  相似文献   
994.
PurposeTo retrospectively evaluate biochemical control and toxicity in patients who underwent 125I seed brachytherapy (BT) for intermediate-risk prostate cancer (PCa).Materials and MethodsBetween January 2004-December 2014, 395 patients with intermediate-risk PCa underwent 125I BT. Of these, 117 underwent preoperative planning (PP; 145 Gy) and 278 real-time intraoperative preplanning (IoP; 160 Gy). All patients were followed for ≥ 6 months (> 5 years in 48% of patients and > 7 years in 13%). Median follow-up was 59 months.ResultsBiochemical relapse-free survival (BRFS) rates at 5 and 8 years were, respectively, 91.7% and 82.1%. By treatment group, the corresponding BRFS rates were 93.5% and 90% for IoP and 89% and 76.8% for PP. The maximum dose to the urethra remained unchanged (217 Gy) despite the dose escalation (from 145 to 160 Gy), without any significant increase in treatment-related toxicity (p = 0.13). Overall toxicity outcomes in the series were excellent, with only 3 cases (0.76%) of grade 3 genitourinary toxicity.ConclusionThe real-time intraoperative planning technique at 160 Gy yields better biochemical controls than the preoperative planning technique at 145 Gy. Dose escalation did not increase urinary toxicity. The excellent results obtained with the IoP BT technique support its use as the first treatment option in this patient population.  相似文献   
995.
Immunocytochemical studies using antibodies raised against a 62-kDa membrane protein isolated from developing soybean (Glycine max (L.) Merr.) cotyledons were performed on leaf tissue of spinach (Spinacia oleracea L.). This 62-kDa protein was labeled by 6′-deoxy-6′-(4-azido-2-hydroxy)-benzamidosucrose (HABS), a photoaffinity sucrose analogue (K. G. Ripp et al., 1988, Plant Physiol.88, 1435–1445). Western-blot analysis of spinach plasma-membrane proteins indicated a cross-reactive polypeptide identical in molecular mass to that found in soybean. Indirect immunogold labeling of resin-embedded sections of fully expanded leaf tissue resulted in specific localization of colloidal gold on the sieve-tube plasma membrane. The label was uniform and, except for a few non-specific gold particles over the cell wall, all other cellular organelles and membrane systems were free of label. With the exception of occasional gold particles associated with the companion-cell plasma membrane, all other cell types of the leaf contained little or no label. Control sections treated with non-immune rabbit immunoglobulin-G were also essentially free of label. Immunogold labeling of young leaves, in which the phloem contained no mature sieve-tube members, were free of label for the 62-kDa protein. However, young leaf tissue in which mature or nearly mature sieve tubes could be identified, contained immunolabel associated with the sieve-tube plasma membranes. Similar results were obtained with mature leaf tissue of sugar beet (Beta vulgaris L.). The results of the immunocytochemical studies are consistent with the suggestion that the concentrating step in the phloem-loading process in this species may occur across the sieve-tube plasma membrane. This paper is dedicated to the memory of William A. Dungey  相似文献   
996.
《Current biology : CB》2023,33(6):1179-1184.e3
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997.
Dietary polyphenols are abundant micronutrients in our diet and paly major role in prevention of degenerative diseases. The binding efficacy of antioxidant polyphenols resveratrol, genistein, and curcumin with PAMAM-G3 and PAMAM-G4 nanoparticles was investigated in aqueous solution at physiological conditions, using multiple spectroscopic methods, TEM images, and docking studies. The polyphenol bindings are via hydrophilic, hydrophobic, and H-bonding contacts with resveratrol forming more stable conjugates. As PAMAM size increased the loading efficacy and the stability of polyphenol-polymer conjugates were increased. Polyphenol binding induced major alterations of dendrimer morphology. PAMAM nanoparticles are capable of delivery of polyphenols in vitro.  相似文献   
998.
999.
Transport of animals is a stressful procedure often resulting in significant losses for the slaughter plant. This study aimed to determine whether or not pigs would benefit from a loading density (low density (LD)) (179 kg/m2) below the normal EU standard loading density (normal density (ND)) (235 kg/m2). Eight similar, 550-km-long road journeys, were followed in which fattening pigs were transported across Germany from farm to slaughter plant. During each journey all pigs were transported at LD (n=4) or ND (n=4). Twelve female pigs per journey (total n=96) were randomly selected for measurement and monitoring of body temperature, behaviour, heart rate and blood parameters. Throughout the journeys, LD pigs displayed more resting behaviour than ND pigs. Average body temperature was lower (P<0.05) for pigs transported at LD (38.0±0.07°C) than those transported at ND (38.3±0.06°C). During loading heart rate increased in both ND and LD pigs and declined after the vehicle had been closed before departure but remained slightly elevated in ND pigs. Pigs transported at ND displayed signs of stress (elevated HR and body temperatures) during the drivers’ break. Blood parameters were only slightly (not significant) effected by loading density. Results indicate that pigs are more capable of adapting to long (550 km) transport conditions when loaded at a density below the present EU requirement.  相似文献   
1000.
Mechanical loading of the spine is a major causative factor of degenerative changes and causes molecular and structural changes in the intervertebral disc (IVD) and the vertebrae end plate (EP). Pleiotrophin (PTN) is a growth factor with a putative role in bone remodeling through its receptor protein tyrosine phosphatase beta/zeta (RPTPβ/ζ). The present study investigates the effects of strain on PTN and RPTPβ/ζ protein expression in vivo. Tails of eight weeks old Sprague-Dawley rats were subjected to mechanical loading using a mini Ilizarov external apparatus. Rat tails untreated (control) or after 0 degrees of compression and 10°, 30° and 50° of angulation (groups 0, I, II and III respectively) were studied. PTN and RPTPβ/ζ expression were evaluated using immunohistochemistry and Western blot analysis. In the control group, PTN was mostly expressed by the EP hypertrophic chondrocytes. In groups 0 to II, PTN expression was increased in the chondrocytes of hypertrophic and proliferating zones, as well as in osteocytes and osteoblast-like cells of the ossification zone. In group III, only limited PTN expression was observed in osteocytes. RPTPβ/ζ expression was increased mainly in group 0, but also in group I, in all types of cells. Low intensity RPTPβ/ζ immunostaining was observed in groups II and III. Collectively, PTN and RPTPβ/ζ are expressed in spinal deformities caused by mechanical loading, and their expression depends on the type and severity of the applied strain.  相似文献   
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