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51.
D. Grotemeyer A. Voiculescu F. Iskandar M. Voshege D. Blondin K.M. Balzer L.C. Rump W. Sandmann 《Transplantation proceedings》2009,41(10):4047-4051
Introduction
The acceptance of a living donor kidney bearing cysts might implicate complications after the transplantation due to the natural history of renal cysts. We have presented our experience with transplantation of living donor kidneys containing cysts but not polycystic disease.Patients and methods
We retrospectively reviewed donor and recipient records of all living kidney transplants performed between January 1997 and April 2008. We analyzed serum creatinine and urea levels, as well as ultrasound scans concerning cyst size and morphology at hospital discharge as well as at 12 and 24 months after transplantation.Results
Among 268 living kidney transplantations, we noted 25 donors with renal cysts. In the computed tomography scan reports, 19 kidneys were described to show a single and six, multiple cysts. The size of 10 single cysts was <5 mm; the other nine were a mean of 17.33 mm. Two of the multiple cyst kidneys had lesions <5 mm; in four kidneys, the mean cyst size was 27.25 mm. The renal function of the recipients was normal or almost normal at discharge with a tendency to lower levels at 12 and 24 months after transplantation. Ultrasound revealed changes in cyst diameter among 6/23 kidneys; the mean diameter increased after 12 months, namely, 8.25 mm to 11.5 mm after 24 months. The subgroup of patients with enlarged cysts showed creatinine and urea levels slightly higher than in the entire group. No aspects of malignancy were found, according to the Bosniak and Israel classification system. One suspicious cyst was tomographically confirmed to be hemorrhagic without any need for treatment. None of the living donors had any problems related to the donor nephrectomy or a need for dialysis due to renal insufficiency in the long term. In addition, the living donors who had even beforehand cystic lesions in their contralateral nonremoved kidney at the time of transplantation did not show complications upon follow-up.Conclusions
In our study, 25 living donor kidneys carried cysts. Neither cyst-related complications nor dysfunction of the transplanted organs occurred. An unroofing or excision of the cyst was generally not necessary. Regular ultrasound scans and optional computed tomography scans are recommended for follow-up. Based on this experience, we concluded that kidneys presenting cystic diseases should be considered to be suitable for transplantation without a hazard to the recipients, thus extending the pool of organs. 相似文献52.
Rokey R; Verani MS; Bolli R; Kuo LC; Ford JJ; Wendt RE; Schneiders NJ; Bryan RN; Roberts R 《Radiology》1986,158(3):771-774
The feasibility of using magnetic resonance (MR) imaging to estimate myocardial infarct size was explored in an in vitro model using only the inherent differences in contrast between infarcted and noninfarcted myocardium. Eight dogs underwent coronary occlusion; their hearts were removed 6 hours later. Estimates of T2 for normal and infarcted myocardium were derived from MR images. Infarct size was quantified anatomically using triphenyltetrazolium-chloride (TTC) staining and compared with MR estimates. The T2 values derived from the images clearly discriminated between infarcted (126 +/- 22 msec) and normal myocardium (88 +/- 10 msec, P less than .05), providing images with good contrast between normal and infarcted myocardium. Comparable differences in T2 values were also noted from spectrometric determinations. Estimates of infarct size by MR imaging compared well with TTC estimates (r = 0.98) over a wide range of infarct sizes from 3% to 29% of the left ventricular mass. These results suggest the potential for in vivo quantification of infarct size based on the inherent contrast difference between infarcted and normal myocardium. 相似文献
53.
Blood loss and replacement in total hip arthroplasty: a multicenter study. The Preoperative Autologous Blood Donation Study Group 总被引:1,自引:0,他引:1
To determine blood loss, the number of transfusions, and the hemoglobin levels achieved in patients via transfusion in the course of total hip arthroplasty, 324 patient records from 1987 through 1989 were reviewed at three university and three community hospitals. Calculated blood loss was 3.2 +/- 1.3 units in primary procedures and 4.0 +/- 2.1 units in revision procedures (mean +/- SD). Of 777 red cell units transfused, 455 (59%) were autologous units. Transfused patients received 2.0 +/- 1.8 units for primary procedures and 2.9 +/- 2.3 units for revision procedures (mean +/- SD). The maximum number of units given to 95 percent of the transfused patients was 4 for primary procedures and 6 for revision procedures. The mean postoperative hemoglobin level after all transfusions was 103 to 110 g per L, regardless of patient age group of physical status, autologous donor status, or hospital. No difference in length of hospital stay was observed for patients less than 65 years old with hemoglobin concentrations of 80 to 139 g per L at discharge. 相似文献
54.
A F Rump U Siekmann D C Fischer G Kalff 《Aviation, space, and environmental medicine》1999,70(8):769-772
METHODS: The disposition of drugs may be influenced by hyperbaric conditions, in particular by changes of liver perfusion. The effect of hyperbaric hyperoxia on the pharmacokinetics of lidocaine, a drug eliminated in the liver with a perfusion-limited clearance, was investigated in human volunteers in a crossover trial. METHODS: A single dose lidocaine i.v. bolus (0.69 or 0.75 mg x kg(-1)) was administered to two volunteers under normobaric conditions (NB: 1 bar or 0.1 MPa, air) and under hyperbaric/hyperoxic conditions (HBO: 2.5 bar or 0.25 MPa, alternating 100% O2-breathing for 20 min and air breathing for 5 min). Blood samples were serially collected for 5 h (NB) or 75 min (HBO), and lidocaine concentration in serum was measured by immunoassay. Data were analyzed assuming linear kinetics and an open two-compartment model. RESULTS: At 1 bar or 0.1 MPa, lidocaine injection caused only slight dizziness and buzzing in the ear. Heart rate and blood pressure were not influenced. Under HBO, lidocaine injection caused marked dizziness and buzzing in the ears, sweating, tremor and coordination-disturbances, even though maximal lidocaine concentrations (0.63 mg x L(-1) and 0.70 mg x L(-1)) were far below therapeutic serum concentrations (1.5-5.0 mg x L(-1)). Pharmacokinetic parameters of lidocaine were similar to those published earlier (T1/2beta: 110+/-16 min; CI: 12.6+/-2.9 ml x min(-1) x kg(-1); Vss: 1.73+/-0.18 L x kg(-1)). There was no indication for effects of HBO on the disposition of lidocaine (p > 0.05). CONCLUSION: The pharmacokinetics of lidocaine do not seem to be influenced in a clinically relevant way in humans by a single HBO-exposure under usual therapeutic conditions. Side effects of lidocaine at 2.5 bar or 0.25 MPa may be caused by pharmacodynamic interactions between lidocaine and hyperbaric/hyperoxic conditions. 相似文献
55.
Data obtained on 426 consecutive patients referred to a breast center by 122 physicians, including family practitioners, general surgeons, and other specialists, showed that the obstetricians-gynecologists referred the greatest average number of patients per physician, with more than 50% of these referrals for screening mammography. Internists referred fewer patients by nearly a factor of ten, with only one-third of these patients referred for screening mammography. Internists may be the weakest link in the utilization of screening mammography. 相似文献
56.
57.
Forty-one proved cases of acute acalculous cholecystitis imaged with technetium-99m iminodiacetic acid (IDA) cholescintigraphy were retrospectively analyzed. After the exclusion of one indeterminate scan (showing poor initial hepatic uptake and excretion), the study yielded a 92.5% (37 of 40) sensitivity for the detection of cystic or common bile duct obstruction. Each of the three patients with false-negative scintigrams had other abnormal scintigraphic findings suggestive of biliary tract disease. Of the 20 patients (48.8%) with focal or diffuse gangrenous cholecystitis or perforation, seven (35%) exhibited either free peritoneal spill or increased pericholecystic activity to indicate the presence of advanced disease. 相似文献
58.
Intestinal absorption of gabapentin in rats 总被引:1,自引:0,他引:1
Gabapentin (1-aminomethyl-)cyclohexaneacetic acid, G? 3450, CI-945; CAS 60142-96-3) is a new gamma-aminobutyric acid (GABA) analogous compound that has shown an anticonvulsive effect as well as low toxicity in preclinical and clinical studies. The substance is well absorbed after oral administration and penetrates the blood-brain barrier. The aim of experiments was to study the mechanism of intestinal absorption, the relationship between the absorption rate and the applied concentration and whether the absorption rate differs between different parts of the intestine. For this purpose, isolated intestinal segments of rats (everted sac preparations) were used. Due to the fact that gabapentin is not metabolized in the intestine, its concentration in the mucosal and serosal compartments could be determined by scintillation counting of 3H-gabapentin. The results showed that gabapentin was absorbed by simple diffusion because neither indications for an uphill nor for a carrier-mediated transport could be demonstrated. The absorption rate was linearly related in the concentration range from 0.001 to 100 mmol/l. There was no significant difference between the absorption rate in the three parts of the small intestine at 1 and 10 mmol/l, while the absorption rate was significantly (p less than 0.01) lower in the colon. 相似文献
59.
目的:为获得组织工程化自体血管,观察体外静态培养条件下犬内皮细胞与平滑肌细胞联合培养组织学及形态学的特征。方法:实验于2004-07/2005-06在首都医科大学宣武医院外科院级实验室完成。①实验材料:雄性杂种犬,3个月龄,体质量8~12kg。②实验方法:贴块法及酶解法对犬内皮细胞及平滑肌细胞进行原代分离培养及扩增,将第Ⅱ代平滑肌细胞以1×109L-1的密度种植于胶原膜上培养13d,再将第Ⅱ代内皮细胞接种于生长平滑肌细胞的胶原膜上2d。③实验评估:行苏木精-伊红染色同时扫描电镜和透射电镜观察平滑肌细胞和内皮细胞在胶原载体上联合培养后的形态。结果:苏木精-伊红染色见平滑肌细胞较均匀的分布于支架材料表面及内部;扫描电镜下,平滑肌细胞可以在胶原载体材料上生长,增殖明显并在短期内形成多层细胞。内皮细胞与平滑肌细胞联合培养2d就可在平滑肌细胞层表面获得连续的单层内皮细胞层。结论:在短期静态培养条件下犬的血管平滑肌细胞和内皮细胞可以在胶原载体材料上形成具有两层细胞结构的组织工程化动脉血管组织片。 相似文献
60.
Blood group A immunodeterminants on human red cells differ in biologic activity and sensitivity to alpha-N-acetylgalactosaminidase 总被引:1,自引:0,他引:1
BACKGROUND: Epitopes of blood group A antigen can be enzymatically cleaved from red cells (RBCs), but the extent of cleavage required for normal survival in allogeneic blood transfusion recipients is unknown. Therefore, the cleavage rates were studied for A antigen epitope binding of 1) complement-activating anti-A, 2) Dolichos biflorus anti- A, lectin, and 3) hemagglutinating anti-A during incubation with a purified alpha-N-acetylgalactosaminidase, E.C. 3.2.1.49 (alpha- GalNAc'ase). STUDY DESIGN AND METHODS: Suspensions of group A RBCs were incubated with alpha-GalNAc'ase. Cells were removed at intervals, washed, and tested for loss of binding by monoclonal, polyclonal, and complement-activating anti-A, D. biflorus anti-A1 lectin, and Ulex europaeus anti-H lectin. RESULTS: A epitopes binding D. biflorus lectin were highly susceptible to alpha-GalNAc'ase; simultaneously with their loss, binding with U. europaeus lectin emerged. Loss of complement- mediated hemolysis was slower. A epitopes binding hemagglutinating anti- A were most resistant. Cleavage of A epitopes from membrane glycosphingolipids with short oligosaccharide chains was similarly resistant. Rates of cleavage from A1 and A2 RBCs were similar. CONCLUSION: RBC epitopes of blood group A differ in susceptibility to cleavage and biologic reactivity, which suggests that subsets mediating important biologic functions exist on functionally and topographically distinct membrane glycoconjugates. 相似文献