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11.
Colleen Delaney Barbara Piscopo 《Journal for nurses in staff development》2004,20(4):157-61; quiz 162-3
The nursing profession is facing a serious shortage in all areas including BSN completion programs. The purpose of this study was to explore associate degree and diploma nurses' perceptions of the benefits and barriers to RN-BSN programs. In addition, factors that would facilitate degree completion in academia and work environments were examined. 相似文献
12.
Cerebral radioprotection by pentobarbital: dose-response characteristics and association with GABA agonist activity 总被引:5,自引:0,他引:5
Pentobarbital reduces cerebral radiation toxicity; however, the mechanism of this phenomenon remains unknown. As an anesthetic and depressant of cerebral metabolism, pentobarbital induces its effects on the central nervous system by stimulating the binding of gamma-aminobutyric acid (GABA) to its receptor and by inhibiting postsynaptic excitatory amino acid activity. The purpose of this study is to investigate the role of these actions as well as other aspects of the radioprotective activity of pentobarbital. Fischer 344 rats were separated into multiple groups and underwent two dose-response evaluations. In one set of experiments to examine the relationship of radioprotection to pentobarbital dose, a range of pentobarbital doses (0 to 75 mg/kg) were given intraperitoneally prior to a constant-level radiation dose (70 Gy). In a second series of experiments to determine the dose-response relationship of radiation protection to radiation dose, a range of radiation doses (10 to 90 Gy) were given with a single pentobarbital dose (60 mg/kg intraperitoneally). Further groups of animals were used to evaluate the importance of the timing of pentobarbital administration, the function of the (+) and (-) isomers of pentobarbital, and the role of an alternative GABA agonist (diazepam). In addition, the potential protective effects of alternative methods of anesthesia (ketamine) and induction of cerebral hypometabolism (hypothermia) were examined. Enhancement of survival time from acute radiation injury due to high-dose single-fraction whole-brain irradiation was maximal with 60 mg/kg of pentobarbital, and occurred over the range of all doses examined between 30 to 90 Gy. Protection was seen only in animals that received the pentobarbital before irradiation. Administration of other compounds that enhance GABA binding (Saffan and diazepam) also significantly enhanced survival time. Ketamine and hypothermia were without protective effect. Protection from acute radiation-induced mortality by pentobarbital in the rat model is a reproducible phenomenon and is associated with the GABA agonistic activity of the compound. This property of GABA agonists offers the potential for a novel approach to enhancement of the efficacy of radiation therapy in the treatment of brain tumors. 相似文献
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On inpatient psychiatric units, nurses control the tone, pace, and activity level of the environment. But under the influence of factors such as high patient acuity and negative group contagion, a milieu can become unacceptably loud and chaotic. A volatile milieu is a potentially dangerous environment because patients' anxiety and agitation can quickly lead to acting out and aggression. This article focuses on how nurses can regain control of a milieu spiralling into chaos by tightening the structure of the routine, anticipating potential problems, and maintaining a confident calm manner. The charge nurse orchestrates the staff group's response to escalation through detailed planning, decisive interventions, and strategic use of every available resource. 相似文献
15.
Kinnison ML; Perler BA; Kaufman SL; Mitchell SE; Kadir S; Williams GM; White RI Jr 《Radiology》1986,160(3):727-730
In situ saphenous vein grafts are being used with increasing frequency for bypass procedures involving the femoral and popliteal arteries. Complications of these procedures include anastomotic stenoses and persistent arteriovenous fistulae that may result in failure of the graft. Balloon angioplasty and embolotherapy with detachable balloons were employed successfully in three or four recent cases of patients with complications from in situ grafts. Tailored angiography is essential for evaluating in situ grafts, and interventional techniques are extremely useful for managing complications. 相似文献
16.
Two fast magnetic resonance (MR) imaging techniques, advanced Fourier and partial-flip imaging, were used at 0.35 T to examine 21 patients with suspected intracranial lesions; the results were quantitatively compared with a conventional spin-echo study. Both of the fast MR techniques yielded a fourfold reduction in imaging time per section. The advanced Fourier sequence showed contrast that was identical to the conventional spin-echo study with signal-to-noise ratios of 58% and 57% for the first and second echoes, respectively. The partial-flip sequence showed a contrast of 109% and 57% for lesions versus substantia alba, and 107% and 78% for substantia grisea versus substantia alba relative to the first and second echoes of the conventional spin-echo study. The partial-flip sequence was particularly sensitive to magnetic susceptibility; this produced artifacts that may undermine the usefulness of partial flip for routine screening in certain parts of the brain. However, this susceptibility significantly improved the detection of intracranial hemorrhage when compared with the spin-echo sequence, particularly when combined with phase mapping of the partial-flip study. 相似文献
17.
Renal transplantation from elderly living donors 总被引:1,自引:0,他引:1
N Sumrani V Delaney Z K Ding R Davis P Daskalakis A Tejani K Butt J Hong 《Transplantation》1991,51(2):305-309
A worldwide shortage of cadaveric donors has led to the increased utilization of elderly living donors, with controversial results. In an attempt to assess the effect of donor age on graft survival and subsequent renal function, we analyzed our clinical results in 276 consecutive recipients of living related renal transplants spanning both the cyclosporine and the azathioprine eras, of whom a total of 44 recipients received kidneys from donors over 55 years old. All recipients were otherwise similar in age, race, haplotype mismatch, number of retransplants, and number of pretransplant transfusions, apart from an increased number of diabetics among the CsA-treated recipients of elderly kidneys (38% vs. 14%). The cumulative patient and graft survival rates at 1 and 5 years were independent of donor age whether CsA or AZA was utilized. Nor was the incidence of rejection or infection significantly different in the older donor group when compared with the younger cohort. Short-term and intermediate-term renal function, as assessed by serum creatinine, was however poorer but stable in the older donor group when compared with the younger one. The mean serum creatinine levels at 1 year in the CsA- and AZA-treated recipients of kidneys from older donors were 2.4 and 2.0 mg/dl, respectively, compared with 1.6 and 1.4 mg/dl, respectively, when the donor age was less than 55 years (P less than 0.001). Since renal function at the end of the first posttransplant year is considered a determinant of long-term graft survival, this is a cause for concern, but in view of the universal shortage of organs and the negligible morbidity to donors, renal transplantation from elderly living donors remains an acceptable practice. 相似文献
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19.
高效液相色谱法测定右旋儿茶素血浆浓度及药代动力学参数 总被引:1,自引:0,他引:1
本文建立了体液中右旋儿茶素的RP-HPLC测定方法。采用C_(18)键合相硅胶为填料的固相提取柱进行样品预处理,右旋儿茶素的提取回收率为79.8%.应用二极管阵列检测器对色谱峰纯度进行鉴定。该法精密度好,方法回收率近100%,日内、日间的变异系数为2.4~5.6%,血浓69.6~1160 ng/ml范围内呈线性关系,r=0.9993。家兔静注右旋儿茶素18mg/kg,其药代动力学过程符合二室模型,分布相半衰期为0.129 h,消除相半衰期为1.19h。 相似文献