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991.
Enterocystoplasty in preparation for renal transplantation in children with severely dysfunctional bladders is widely accepted by pediatric urologists and transplant surgeons alike. The risk for septic and other complications in this immunosuppressed population remains elevated however, since problems inherent to the use of bowel or stomach in the urinary tract become magnified in these patients. In addition, simultaneous enterocystoplasty and transplantation carry a significant risk, and we must therefore subject these children to two major operations within a short time span. We herein describe our experience with combining simultaneously ureterocystoplasty and renal transplantation in a child. We believe this procedure has major relevance, in particular in the group of patients with posterior urethral valves and chronic renal failure. 相似文献
992.
993.
In free tissue transfer and replantation surgery, there is a debate over whether any pharmacologic agents should be used to improve vessel patency and tissue survival. Because tissue-plasminogen activator (t-PA) is a highly effective and safe fibrinolytic, it may be useful in obtaining and maintaining vessel patency. The direct effects of t-PA on skeletal muscle hemodynamics and leukocyte activation at the microcirculatory level were investigated. Male Sprague-Dawley rats (n = 20) were divided into three experimental groups: control (n = 8), vehicle (n = 6), and t-PA (n = 6). Using the cremaster muscle flap model and intravital microscopy, red blood cell velocity, vessel diameter, capillary perfusion, endothelial edema index, and leukocyte-endothelial interactions (rolling, adhering, and transmigrating leukocytes) in postcapillary venules were measured. In the vehicle and t-PA groups, vehicle or t-PA was infused by means of a catheter inserted into the lower abdominal aorta for local infusion. Except for a significant reduction in the diameter of the first order arterioles from 117 microm to 82 microm (medians; p = 0.026), t-PA did not significantly affect red blood cell velocity, vessel diameter, or capillary perfusion compared with vehicle. However, leukocyte-endothelial interactions did differ significantly in postcapillary venules. Adhering leukocytes counted per visual field decreased from 4.67 in the vehicle group and 3.50 in the control group to 1.67 in the t-PA group (medians; p = 0.015 and p = 0.005, respectively); transmigrating leukocytes in the t-PA group decreased from 4.75 in the vehicle group and 3.50 in the control group to 1.67 in the t-PA group (medians; p = 0.002 and p = 0.043, respectively). t-PA treatment significantly decreased the number of both adhering and transmigrating leukocytes. These novel findings on leukocyte-endothelial interactions suggest that t-PA has anti-inflammatory effect. 相似文献
994.
G Epple KM van der Drift JE Thomas-Oates O Geiger 《Canadian Metallurgical Quarterly》1998,180(18):4950-4954
Rhizobial capsular polysaccharides (RKPs) play an important role in the development of a nitrogen-fixing symbiosis with the plant host and in Sinorhizobium meliloti AK631 functional rkpABCDEF genes are required for the production of RKPs. After cloning the rkpF gene, we overexpressed and purified the derived protein product (RkpF) in Escherichia coli. Like acyl carrier protein (ACP), the RkpF protein can be labeled in vivo with radioactive beta-alanine added to the growth medium. If homogeneous RkpF protein is incubated with radiolabeled coenzyme A in the presence of purified holo-ACP synthase from E. coli, an in vitro transfer of 4'-phosphopantetheine to the RkpF protein can be observed. The conversion from apo-RkpF protein to holo-RkpF protein seems to go along with a major conformational change of the protein structure, because the holo-RkpF protein runs significantly faster on native polyacrylamide gel electrophoresis than the apo-RkpF protein. Electrospray mass spectrometric analysis reveals a mass of 9,585 for the apo-RkpF protein and a mass of 9,927 for the holo-RkpF protein. Our data show that RkpF is a novel ACP. 相似文献
995.
JE Hartley S Ahmed R Milkins G Naylor JR Monson PW Lee 《Canadian Metallurgical Quarterly》1996,83(8):1156-1157
Eighty-five consecutive patients were randomized to undergo mass closure of the abdomen with no. 1 polydioxanone mounted on either a blunt-tipped (n = 46) or cutting (n = 39) needle. Gloves were changed before closure and tested for perforation afterwards using standard air or water techniques. Fourteen pairs of gloves were punctured when using a cutting needle, and three pairs when a blunt-tipped needle was used. The majority of punctures were to the non-dominant glove. The surgeon was aware of the puncture in eight of the 14 instances involving a sharp needle and in one of the three involving a blunt-tipped needle. Blunt-tipped needles, while not eliminating the risk, significantly reduced the incidence of surgical glove puncture (P < 0.001, Fisher's exact test). The use of cutting needles for abdominal closure should be abandoned. 相似文献
996.
This study investigated whether finding meaning in response to an HIV-related stressor was associated with changes in immune status and health. Forty HIV-seropositive men who had recently experienced an AIDS-related bereavement completed interviews assessing cognitive processing and finding meaning after the loss and provided blood samples for a 2- to 3-year follow-up. AIDS-related mortality over an extended follow-up was determined from death certificates. As predicted, men who engaged in cognitive processing were more likely to find meaning from the loss. Furthermore, men who found meaning showed less rapid declines in CD4 T cell levels and lower rates of AIDS-related mortality (all ps < .05), independent of health status at baseline, health behaviors, and other potential confounds. These results suggest that positive responses to stressful events, specifically the discovery of meaning, may be linked to positive immunologic and health outcomes. 相似文献
997.
JE Rall 《Canadian Metallurgical Quarterly》1998,186(11):722-723
998.
Source wavelength modulation by feedback of the interference signal of an unbalanced fiber-optic Michelson interferometer to the driver of the semiconductor laser source gives rise to sawtooth shaped fringes under fiber strain. The dependence of the theoretically predicted fringe asymmetry on feedback gain is verified experimentally. Elimination of the fringe counting directional ambiguity via differentiation of the asymmetric closed loop interference signal is demonstrated for the first time 相似文献
999.
JW Jones SE Schmidt BW Richman KM Itani KJ Sapire MJ Reardon 《Canadian Metallurgical Quarterly》1998,78(5):705-727
In conclusion, surgical myocardial revascularization has utilized diverse methods to increase blood flow to the starving myocardium. These methods initially used the microcirculation as the portal to reach myocytes until angiography showed that the obstructions were macrovascular. This resulted in a 30-year era of direct attack on the coronary blockages by coronary bypass. Surgical conduits unfortunately have longevity considerably less than that of native arteries and are limited in number. Alternative conduits, both biologic and prosthetic, have not yet proved to have the same clinical results as the ITA. More patients are living long enough to have the extensiveness of their disease exhaust conventional therapies. Newer therapy, restricted thus far to untreatables, revisits the microcirculation by making laser channels. These many innovative procedures have benefited hundreds of thousands of patients. They emerged from the probity and innovation of many individual surgeons. 相似文献
1000.
JF Tsai HS Margolis JE Jeng MS Ho WY Chang MY Hsieh ZY Lin JH Tsai 《Canadian Metallurgical Quarterly》1998,86(3):246-251
24 consecutive AIDS patients with wasting, and who had never received anabolic therapies, were evaluated to determine their profile of sex hormones and whether transformation of testosterone (T) to the nuclear androgen, dihydrotestosterone (DHT), was impaired. Eleven (46%) patients had normal testosterone and DHT (group I), 10 (42%) had normal testosterone but low DHT (group II), and 3 (12%) had low testosterone and low DHT (group III). Age, prior opportunistic complications, symptoms, serum albumin, hemoglobin levels, and CD4 lymphocyte counts were similar in the groups. DHT was significantly lower (22.2 +/- 6.8 microg/dl) in group II compared with group I (50.8 +/- 15.3 microg/dl). The ratio of T/DHT, a measure of the conversion of testosterone to DHT, in group I was 15.1 +/- 3.5, which was within the range for eugonadal young men. In group II, the ratio was 22.3 +/- 1.5, indicating a defect in generation of DHT. Patients in group II had lost 9.2 +/- 3.5 kg compared with 5.6 +/- 2.6 kg in group I (p = .015). Thus, a syndrome of low DHT with normal testosterone was associated with significantly greater weight loss than in patients with normal testosterone and DHT. Further studies are needed to clarify whether low DHT is a result of AIDS wasting or is causally related to weight loss and whether androgen therapy in the form of DHT could reverse some of the metabolic changes associated with AIDS wasting. 相似文献