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331.
Systems studies of DDT transport 总被引:1,自引:0,他引:1
H L Harrison O L Loucks J W Mitchell D F Parkhurst C R Tracy D G Watts V J Yannacone 《Science (New York, N.Y.)》1970,170(957):503-508
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333.
Joye SB Leifer I MacDonald IR Chanton JP Meile CD Teske AP Kostka JE Chistoserdova L Coffin R Hollander D Kastner M Montoya JP Rehder G Solomon E Treude T Villareal TA 《Science (New York, N.Y.)》2011,332(6033):1033; author reply 1033
Kessler et al. (Reports, 21 January 2011, p. 312) reported that methane released from the 2010 Deepwater Horizon blowout, approximately 40% of the total hydrocarbon discharge, was consumed quantitatively by methanotrophic bacteria in Gulf of Mexico deep waters over a 4-month period. We find the evidence explicitly linking observed oxygen anomalies to methane consumption ambiguous and extension of these observations to hydrate-derived methane climate forcing premature. 相似文献
334.
Thoesen MS Berg-Foels WS Stokol T Rassnick KM Jacobson MS Kevy SV Todhunter RJ 《American journal of veterinary research》2006,67(10):1655-1661
OBJECTIVE: To analyze a centrifugation-based, point-of-care device that concentrates canine platelets and bone marrow-derived cells. ANIMALS: 19 adult sexually intact dogs. PROCEDURES: Anticoagulated peripheral blood (60 mL) and 60 mL of anticoagulated bone marrow aspirate (BMA) were concentrated by centrifugation with the centrifugation-based, point-of-care device to form a platelet and a bone marrow concentrate (BMC) from 11 dogs. Blood samples were analyzed on the basis of hemograms, platelet count, and PCV. The BMA and BMC were analyzed to determine PCV, total nucleated cell count, RBC count, and differential cell counts. The BMC stromal cells were cultured in an osteoinductive medium. Eight additional dogs were used to compare the BMC yield with that in which heparin was infused into the bone marrow before aspiration. RESULTS: The centrifugation-based, point-of-care device concentrated platelets by 6-fold over baseline (median recovery, 63.1%) with a median of 1,336 x 10(3) platelets/microL in the 7-mL concentrate. The nucleated cells in BMCs increased 7-fold (median recovery, 42.9%) with a median of 720 x 10(3) cells/microL in the 4-mL concentrate. The myeloid nucleated cells and mononuclear cells increased significantly in BMCs with a significant decrease in PCV, compared with that of BMAs. Stromal cell cultures expressed an osteoblastic phenotype in culture. Infusion of heparin into the bone marrow eliminated clot formation and created less variation in the yield (median recovery, 61.9%). CONCLUSIONS AND CLINICAL RELEVANCE: Bone marrow-derived cell and platelet-rich concentrates may form bone if delivered in an engineered graft, thus decreasing the need for cancellous bone grafts. 相似文献
335.
Christensen BW Troedsson MH Murchie TA Pozor MA Macpherson ML Estrada AH Carrillo NA Mackay RJ Roberts GD Langlois J 《Journal of the American Veterinary Medical Association》2006,228(8):1228-1233
CASE DESCRIPTION: A 19-year-old Thoroughbred mare was evaluated at 265 days of gestation with a markedly distended abdomen and edema of the ventral portion of the abdomen. CLINICAL FINDINGS: The uterus was distended over the pelvic rim, making transrectal palpation of the fetus impossible. Transabdominal ultrasonography revealed excessive amounts of fetal fluid. Results of analysis of fluid obtained via amnio- and allantocentesis confirmed that the amniotic cavity was large. TREATMENT AND OUTCOME: The mare was monitored for signs of weakness of the prepubic tendon and abdominal wall. The fetus and placenta were monitored for signs of stress and pending abortion. Flunixin meglumine and altrenogest were administered to the mare. Parturition was attended and occurred at 321 days' gestation. Postpartum complications in the mare included hypovolemic shock and cardiac arrhythmias. Both conditions were treated, and the mare recovered. The foal was considered small, had bilateral angular limb deformities, and was unable to nurse. The foal was given plasma for failure of passive transfer of immunity. Ten months later, the foal underwent procedures to correct limb deformities. CONCLUSIONS AND CLINICAL RELEVANCE: Hydrops conditions are rare in horses, with hydrops allantois occurring more frequently than hydrops amnion; reportedly result in fetal or neonatal death; and may result in death of or injury to the mare. Close monitoring of maternal and fetal health in combination with supportive treatment of the mare can result in the safe progression of a hydrops pregnancy and the birth of a live foal. 相似文献
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337.
Canine pituitary tumours are increasingly treated with stereotactic radiotherapy (SRT). Here, we report clinical outcomes in dogs treated with single‐fraction SRT; we also explore technical aspects of SRT treatment planning. A single‐institution retrospective study was performed, including any dog with a pituitary mass (PM) that was treated using a standardized single‐fraction (16 Gy) SRT protocol between 2014 and 2017. Via medical records review, 13 cases were identified. Nine dogs neurologically improved after SRT. Four dogs experienced MRI‐documented tumour volume reduction. Nine dogs experienced neurologic decline in 1.5 to 18 months after SRT and were euthanized. The median overall survival time was 357 days, with 15% alive 18 months after SRT. To better understand whether SRT target delineation is predictably altered by use of magnetic resonance imaging (MRI) in addition to computed tomography (CT), two radiation oncologists (RO) retrospectively re‐evaluated all imaging studies used for SRT planning in these 13 cases. Gross tumour volume (GTV) was contoured on co‐registered CT and MRIs for each case. In seven cases, CT alone was deemed inadequate for GTV contouring by at least one RO. T1 post‐contrast MRI was considered the ideal image for GTV contouring in 11 cases. Contouring on MRI yielded larger GTV than CT for 11 cases. Inter‐observer variability existed in each case and was greater for MRI. In summary, use of co‐registered CT and MRI images is generally considered advantageous for PM delineation when using SRT. Notably, survival times reported herein are shorter than what has previously been reported for PM treated with finely fractionated full‐course RT protocols. 相似文献