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41.
Effects of sodium salts of various monovalent inorganic anions on transdermal permeation of salicylic acid were investigated. In in-vitro experiment using a Franz-type diffusion cell and excised mouse skin, the permeation-enhancing activities of the sodium salts of inorganic anions were roughly proportional to lyotropic Hofmeister swelling abilities of the anions; F?<SO4 2?<Cl? <ClO4 ?<NO3 <SCN? <Br <I?, i.e. l, Br and SCN increased the flux of drugs through the mouse skin, while F?, SO4 2?, Cl?, ClO4 ? and NO3 ? decreased or did not affect the flux. In invivo experiment using the rabbit as the test animal, the plasma concentration of salicylic acid of the rabbit to which 10%-salicylic acid ointment containing 5%-Nal or NaBr was applied was significantly higher than that of the rabbit to which the ointment without the electrolytes was applied. The amounts of sterol leached out of stratum corneum sheet when the sheet was immersed in aqueous solutions of Nal, NaBr, or NaSCN were much more than that of stratum corneum immersed in aqueous solutions of the other inorganic anions. The FTIR/ATR spectroscopy showed that the peaks at 2853 cm?1 and 2924 cm?1 in the IR absorption spectrum of the stratum corneum sheet of the mouse were shifted to higher frequencies by the anions which enhanced the transdermal drug permeation, while not shifted by the anions which did not have any permeation-enhancing activities or have permeation-reducing activities. These results suggest that sodium salts of some anions such as iodide, bromide and thiocyanate enhance transdermal permeation of salicylic acid through swelling and perturbation of the skin structure by these anions.  相似文献   
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We quantified the financial implications of surgical complications following pancreas transplantation. We reviewed medical and financial records of 49 pancreas transplant recipients at the University of Michigan Health System (UMHS) between 1/6/2002 and 11/22/2004. The association of donor, transplant recipient and financial variables was assessed. The median costs to UMHS of procedures and follow-up were $92,917 for recipients without surgical complications versus $108,431 when a surgical complication occurred, a difference of $15,514 (p = 0.03). Median reimbursement by the payer was $17,363 higher in patients with a surgical complication (p = 0.001). Similar trends (higher insurer costs) were noted when stratifying by payer (public and private) and specific procedure (SPK and PAK). All parties (patient, physician, payer and medical center) should benefit from quality improvement, with payers having a financial interest in pancreas transplant surgical quality initiatives.  相似文献   
44.
Increased expression of the sodium iodide symporter (NIS) is required for effective radioiodine treatment and reporter gene imaging of breast cancer. We investigated the effect of retinoic acid on adenovirus-mediated expression of the human NIS gene in the MCF-7 breast cancer cell line. METHODS: The MCF-7 cell line was infected with recombinant adenovirus carrying the human NIS gene (Rad-NIS). Levels of NIS messenger RNA (mRNA) and protein expression and radioiodine ((125)I) uptake were measured to evaluate adenovirus-mediated NIS gene expression in wild-type and Rad-NIS-infected MCF-7 cells after treatment with all-trans-retinoic acid (ATRA; 10(-8)-10(-6) mol/L). RESULTS: The transduction efficiency of adenovirus in MCF-7 cells at a multiplicity of infection (MOI) of 50 was >60%. After incubation with 10(-6) mol/L ATRA, the mRNA level in Rad-NIS-infected MCF-7 cells increased to 118.5 times that of wild-type MCF-7 cells, whereas the mRNA level in wild-type MCF-7 cells showed only a 2.1-fold increase. Western blot, immunocytochemical staining, and flow cytometry analyses showed that NIS protein expression in MCF-7 cells infected with Rad-NIS increased after ATRA treatment. With ATRA treatment, the amount of (125)I uptake increased in a dose-dependent manner (P < 0.001). The (125)I uptake in wild-type MCF-7 cells increased 3.1-, 5.5-, and 7.6-fold with treatment with 10(-8), 10(-7), and 10(-6) mol/L ATRA, respectively. Rad-NIS-infected cells showed a 4.0-fold increase in (125)I uptake. Treatment of Rad-NIS-infected cells with 10(-8), 10(-7), and 10(-6) mol/L ATRA increased (125)I uptake by 4.9-, 8.2-, and 27.6-fold, respectively, compared with wild-type MCF-7 cells. The level of NIS expression in Rad-NIS-infected MCF-7 cells treated with 10(-6) mol/L ATRA (245.0 +/- 13.7 pmol/10(6) cells) was much greater than the sum of the expression levels seen in ATRA-treated wild-type cells and Rad-NIS-infected wild-type cells. CONCLUSION: Retinoic acid increases adenovirus-mediated NIS expression in MCF-7 cells. Our results indicate that improved efficiency of NIS gene therapy or reporter imaging in breast cancer may be possible with retinoic acid treatment.  相似文献   
45.
We developed a technique of translocation of the pulmonary artery anterior to the ascending aorta without transection of the aorta in the repair of tetralogy of Fallot with absent pulmonary valve. Our technique includes detachment of the main pulmonary artery (MPA) from the pulmonary annulus, vertical division of the MPA, anterior translocation of the pulmonary artery with patch augmentation between the vertically divided MPA.  相似文献   
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Kidney and pancreas transplantation in 2005 improved in quantity and outcome quality, despite the increasing average age of kidney graft recipients, with 56% aged 50 or older. Geography and ABO blood type contribute to the discrepancy in waiting time among the deceased donor (DD) candidates. Allocation policy changes are decreasing the median times to transplant for pediatric recipients. Overall, 6% more DD kidney transplants were performed in 2005 with slight increases in standard criteria donors (SCD) and expanded criteria donors (ECD). The largest increase (39%) was in donation after cardiac death (DCD) from non‐ECD donors. These DCD, non‐ECD kidneys had equivalent outcomes to SCD kidneys. 1‐, 3‐ and 5‐year unadjusted graft survival was 91%, 80% and 70% for non‐ECD‐DD transplants, 82%, 68% and 53% for ECD‐DD grafts, and 95%, 88% and 80% for living donor kidney transplants. In 2005, 27% of patients were discharged without steroids compared to 3% in 1999. Acute rejection decreased to 11% in 2004. There was a slight increase in the number of simultaneous pancreas‐kidney transplants (895), with fewer pancreas after kidney transplants (343 from 419 in 2004), and a stable number of pancreas alone transplants (129). Pancreas underutilization appears to be an ongoing issue.  相似文献   
49.
Performance measurement of the microPET focus 120 scanner.   总被引:6,自引:0,他引:6  
The microPET Focus 120 scanner is a third-generation animal PET scanner dedicated to rodent imaging. Here, we report the results of scanner performance testing. METHODS: A (68)Ge point source was used to measure energy resolution, which was determined for each crystal and averaged. Spatial resolution was measured using a (22)Na point source with a nominal size of 0.25 mm at the system center and various off-center positions. Absolute sensitivity without attenuation was determined by extrapolating the data measured using an (18)F line source and multiple layers of absorbers. Scatter fraction and counting rate performance were measured using 2 different cylindric phantoms simulating rat and mouse bodies. Sensitivity, scatter fraction, and noise equivalent counting rate (NECR) experiments were repeated under 4 different conditions (energy window, 250 approximately 750 keV or 350 approximately 650 keV; coincidence window, 6 or 10 ns). A performance phantom with hot-rod inserts of various sizes was scanned, and several animal studies were also performed. RESULTS: Energy resolution at a 511-keV photopeak was 18.3% on average. Radial, tangential, and axial resolution of images reconstructed with the Fourier rebinning (FORE) and filtered backprojection (FBP) algorithms were 1.18 (radial), 1.13 (tangential), and 1.45 mm full width at half maximum (FWHM) (axial) at center and 2.35 (radial), 1.66 (tangential), and 2.00 mm FWHM (axial) at a radial offset of 2 cm. Absolute sensitivities at transaxial and axial centers were 7.0% (250 approximately 750 keV, 10 ns), 6.7% (250 approximately 750 keV, 6 ns), 4.0% (350 approximately 650 keV, 10 ns), and 3.8% (350 approximately 650 keV, 6 ns). Scatter fractions were 15.9% (mouse phantom) and 35.0% (rat phantom) for 250 approximately 750 keV and 6 ns. Peak NECR was 869 kcps at 3,242 kBq/mL (mouse phantom) and 228 kcps at 290 kBq/mL (rat phantom) at 250 approximately 750 keV and 6 ns. Hot-rod inserts of 1.6-mm diameter were clearly identified, and animal studies illustrated the feasibility of this system for studies of whole rodents and mid-sized animal brains. CONCLUSION: The results of this independent field test showed the improved physical characteristics of the F120 scanner over the previous microPET series systems. This system will be useful for imaging studies on small rodents and brains of larger animals.  相似文献   
50.
We report here our 10-year experience of a biopsy performed at day 14 after transplantation in 304 patients with stable graft function. The factors that may have influenced subclinical rejection were analyzed according to histology. The incidence of subclinical rejection was 13.2%. Addition of mycophenolate mofetile (MMF) as a primary immunosuppressant significantly decreased the incidence of subclinical rejection compared with patients without such treatment (odds ratio, 0.23; p < 0.05). On the other hand, HLA-DR antigen mismatch (odds ratio, 2.39) and unrelated donor (odds ratio, 2.10) were also significantly associated with decreased subclinical rejection (p < 0.05). The incidence of acute rejection in patients with normal findings was lower than in those with borderline changes or subclinical rejection (0.23 +/- 0.05 vs. 0.48 +/- 0.07 and 0.60 +/- 0.11, respectively; p < 0.05). The graft survival rates in patients with subclinical rejection were lower than in patients with normal or borderline changes at 1 (88.4% vs. 97.9% and 99.1%; p < 0.05), 5 (77.8% vs. 96.2% and 95.9%; p < 0.05) and 10 (62.3% vs. 96.2% and 93.7%; p < 0.05) years. Thus, a protocol biopsy performed on day 14 after transplantation is useful for predicting graft survival. Triple therapy including MMF, related donor and HLA-DR antigen match are important factors for reducing subclinical rejection in living-donor renal transplantation.  相似文献   
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