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41.
A dermold cyst, arising from the posterior aspects of the prostate and seminal vesicles, and extending into the pelvis to masquerade as a full bladder, must be exceedingly rare. Ultrasound, computed tomography and especially magnetic resonance imaging (MRI) proved to be invaluable in making the diagnosis, and MRI in particular was very useful in providing an anatomical road map for surgery.  相似文献   
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Persistence of alemtuzumab at lympholytic concentrations after reduced-intensity conditioning allogeneic stem cell transplantations (RITs) could impair immune reconstitution and reduce donor T-cell-mediated graft-versus-leukemia/lymphoma (GVL) effects, derived from the graft or subsequent adoptive immunotherapy. We have studied the pharmacokinetics of alemtuzumab in 2 different groups: RIT (100 mg alemtuzumab in vivo over 5 days) and myeloablative allografts (20 mg alemtuzumab added in vitro to the stem cells prior to return). Alemtuzumab concentrations in RIT patients were in excess of that required to kill infused donor CD52+ cells at the time of transplantation and remained at potentially lympholytic levels (> 0.1 microg/mL) for approximately 56 days after transplantation, 26 days longer than for the myeloablative group. Total lymphocyte counts were significantly lower in the RIT group persisting beyond 6 months after transplantation (P =.005), and median absolute CD4 counts higher than 200 x 106/L were delayed until 9 months after transplantation.  相似文献   
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Obesity is increasing in the United States, not only among adults, but also among children and youth (1). The U.S. Centers for Disease Control and Prevention report the incidence of children at risk for being overweight or obese has doubled in the last two decades (2). Schools can play a role in preventing childhood obesity by serving healthy meals with adequate calories and nutrients, providing nutrition education that encourages healthful food selections, offering opportunities for physical activity and creating school environments that model healthful behaviors.  相似文献   
44.
The toxicity of Ni(II), Co(II) and Cu(II) in animals, and that of Cd(II) in cultured cells, has been associated with generation of the promutagenic lesion 8-oxo-7,8-dihydroguanine (8-oxoguanine) in DNA, among other effects. One possible source of this base may be 8-oxo-7,8- dihydro-2'-deoxyguanosine-5'-triphosphate (8-oxo-dGTP), a product of oxidative damage to the nucleotide pool, from which it is incorporated into DNA. To promote such incorporation, the metals would have to inhibit specific cellular 8-oxo-dGTPases that eliminate 8-oxo-dGTP from the nucleotide pool. The present study was designed to test such inhibition in vitro on 8-oxo-dGTPases from two different species, the human MTH1 protein and Escherichia coli MutT protein. In the presence of Mg(II), the natural activator of 8-oxo-dGTPases, all four metals were found to inhibit both enzymes. For MTH1, the IC50 values (+/- SE; n = 3-4) were 17 +/- 2 microM for Cu(II), 30 +/- 8 microM for Cd(II), 376 +/- 71 microM for Co(II) and 801 +/- 97 microM for Ni(II). For MutT, they were 60 +/- 6 microM for Cd(II), 102 +/- 8 microM for Cu(II), 1461 +/- 96 microM for Ni(II) and 8788 +/- 1003 microM for Co(II). Thus, Cu(II) and Cd(II) emerged as much stronger inhibitors than Ni(II) and Co(II), and MTH1 appeared to be generally more sensitive to metal inhibition than MutT. Interestingly, in the absence of Mg(II), the activity of the enzymes could be restored by Co(II) to 73% of that with Mg(II) alone for MutT, and 34% for MTH1, the other metals being much less or non-effective. The difference in sensitivity to metal inhibition between the two enzymes may reflect the differences in the amino acid ligands, especially the cysteine ligand, outside their evolutionarily conserved Mg(II)-binding active sites, which might indicate predominantly non-competitive or uncompetitive mechanism of the inhibition. The overall results suggest that inhibition of 8-oxo- dGTPases may be involved in the mechanisms of induction of the 8- oxoguanine lesion in DNA by the metal ions studied, especially the non- redox-active Cd(II) cation.   相似文献   
45.
Mucormycosis is a rare fungal infection of childhood, occurring mainly in patients with chronic illnesses such as diabetes and malignancies. The fungus seldom grows in culture and confirmation of the diagnosis depends on histologic examination of infected tissues. To date, the reported natural history of the disease has been rapid progression and a fatal outcome. Therefore, the importance of early diagnosis by tissue biopsy and early treatment with surgical debridement and systemic antifungal therapy cannot be overemphasized. The pulmonary system is the most common site for mucormycosis in patients with leukemia. We report what we believe to be the first successfully treated case of isolated muscular mucormycosis occurring in a child with biphenotypic acute leukemia. The diagnosis was made promptly by tissue examination at the time of surgical debridement. The patient was also given systemic amphotericin-B therapy.   相似文献   
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The role of divalent cations in platelet adherence to deendothelialized human arteries in flowing blood was investigated in an annular perfusion chamber. Spreading of platelets on the subendothelium was impaired below 30 microM of free Ca2+ ions (Ca2+). When Ca2+ was replaced by Mg2+, adherence was unchanged in perfusates without exogenous factor VIII-von Willebrand factor (FVIII-vWF), but the ability of FVIII-vWF to support platelet adherence was lost. Binding of FVIII-vWF to the vessel wall was independent of divalent cations, but bound FVIII-vWF was only able to mediate adherence after exposure to Ca2+. Pretreatment of FVIII-vWF with the calcium chelator EGTA (10 mM) resulted in loss of the ability to facilitate platelet adherence, while the ristocetin cofactor activity remained intact. Full restoration of the ability to mediate platelet adherence could only be obtained by prolonged dialysis against Ca2+ in the millimolar range. These data indicate that divalent cations have at least two separate roles to play in supporting platelet adherence: (1) platelet spreading on the subendothelium requires Ca2+ or Mg2+; (2) FVIII-vWF should be exposed to Ca2+ to obtain its optimal biologic activity in supporting platelet adherence.  相似文献   
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