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51.
Gerald L DeNardo Arutselvan Natarajan Saphon Hok Julie Perkins Monique Cosman Sally J DeNardo Felice C Lightstone Gary R Mirick Laird A Miers Rodney L Balhorn 《Journal of nuclear medicine》2007,48(8):1338-1347
Despite their large size, antibodies (Abs) are suitable carriers to deliver systemic radiotherapy, often molecular image-based, for lymphoma and leukemia. Lym-1 Ab has proven to be an effective radioisotope carrier, even in small amounts, for targeting human leukocyte antigen DR (HLA-DR), a surface membrane protein overexpressed on B-cell lymphoma. Pairs of molecules (referred to as ligands), shown by computational and experimental methods to bind to each of 2 sites within the Lym-1 epitopic region, have been linked to generate small (<2 kDa) molecules (referred to as selective high-affinity ligands [SHALs]) to mimic the targeting properties of Lym-1 Ab. METHODS: A lysine-polyethylene glycol (PEG) backbone was used to synthetically link 2 of the following ligands: deoxycholate, 5-leuenkephalin, triiodothyronine, thyronine, dabsyl-L-valine, and N-benzoyl-L-arginyl-4-amino-benzoic acid to generate a series of 13 bidentate SHALs with a biotin or 1,4,7,10-tetraazacyclododecane-N,N',N',N'-tetraacetic acid (DOTA) chelate attached to the linker. These SHALs have been assessed for their selectivity in binding to HLA-DR10-expressing cells and for their pharmacokinetics and tissue biodistribution in mice. Biotinylated versions of these SHALs discriminated cell lines positive for HLA-DR10 expression with near-nanomolar affinity. The DOTA versions of 4 SHALs were labeled with (111)In for pharmacokinetic studies in mice with HLA-DR10-expressing malignant Raji xenografts. RESULTS: The bidentate, biotinylated, and DOTA-SHALs were synthesized in high-purity, multimilligram amounts. Mean radiochemical and product yields and purities were 90%, 75%, and 90% at mean specific activities of 3.9 MBq/microg (105 microCi/microg) for the (111)In-labeled SHALs. As expected, rapid blood clearance and tumor targeting were observed. The pharmacokinetics of the SHALs was influenced by the component ligands. Biliary clearance, kidney localization, and serum receptor binding contributed to less favorable tumor targeting. CONCLUSION: A series of SHALs was readily synthesized in multimilligram amounts and showed the expected selective binding in vitro. Better selection of the SHAL components should provide second-generation SHALs with improved properties to fulfill the substantial potential of these novel molecular carriers for targeting. 相似文献
52.
Structure function interface with sequential shortening of basal and apical components of the myocardial band 总被引:1,自引:0,他引:1
Manuel Castella Gerald D. Buckberg Saleh Saleh Morteza Gharib 《European journal of cardio-thoracic surgery》2005,27(6):980-987
Objective: To mechanically test the intact cardiac structure to determine the sequence of contraction within the myocardial mass to try to explain ejection and suction. Methods: In 24 pigs (30–85 kg), segment shortening at the site of sonomicrometer crystals was continuously recorded. The ECG evaluated rhythm, and Millar pressure transducers measured intraventricular pressure and dP/dt. Results: Study of segment shortening defined a sequence of contraction within the myocardial mass, starting at the free wall of the right ventricle and on the endocardial side of the antero-septal wall of the left. Crystal location defined underlying contractile trajectory; transverse in right ventricle followed by basal posterior left ventricle, and from the endocardial anterior wall to the posterior apical segment and finally to the epicardial side of the anterior wall. Mean shortening fraction averaged 18±3%, with endocardial exceeding epicardial shortening by 5±1%. Epicardial segment crystal displacement followed endocardial shortening by 82±23 ms in the anterior wall, and finished 92±33 ms after endocardial shortening stopped, time frame that matches the interval of fast drop of ventricular pressure and the start of suction. Conclusions: Crystal shortening fraction sequence followed the rope-like myocardial band model to contradict traditional thinking, with two starting points of excitation–contraction, the right anterior free wall of the right ventricle, and the endocardial side of the anterior wall. Active suction may be due to active shortening of the epicardial fibers of the anterior wall, because relaxation was not detected when both mitral and aortic valves were closed during the interval previously termed ‘isovolumetric relaxation’. 相似文献
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Despite recent advances in surgical technique using laparoscopic and robotic approaches for the management of early organ-confined prostate cancer, most contemporary reports demonstrate significant rates of erectile dysfunction comparable to standard open approaches. Controversy remains related to many of the pre-and postoperative management strategies, including agents to enhance nerve recovery, erectogenic drugs, antioxidants, vasoactive injectables, vacuum erection devices and nerve grafting procedures. Additionally, the optimal timing of these interventions and their duration, dose, frequency and outcome thresholds remain ill-defined. In our paper, we provide a comprehensive literature review involving both the basic and clinical data surrounding rehabilitative approaches. 相似文献
56.
Gregory T. Bales M.D. Susan K. Fellner M.D. Gerald W. Chodak M.D. Daniel B. Rukstalis M.D. 《Urology》1994,43(6)
Hypertension arising from retained native kidneys complicates the management of recipients of renal transplants. Reluctance to administer angiontensin-converting enzyme inhibitor (ACEI) drugs to patients taking cyclosporine has reopened the question of performing native nephrectomies for poorly controlled, renin-dependent hypertension. We report the first published cases of simultaneous bilateral laparoscopic nephrectomies in 2 patients: 1 in preparation for living-related donor transplantation and the other ten months following cadaver transplantation in a patient whose end-stage renal disease was from malignant nephrosclerosis. Both had very severe hypertension resistant to multiple drugs and both became normotensive with little or no antihypertensive medication following nephrectomies. A bilateral nephrectomy is currently feasible using a laparoscopic approach. 相似文献
57.
Deborah W. Knapp Ralph C. Richardson Gerald D. Bottoms Robert Teclaw Thomas C. K. Chan 《Cancer chemotherapy and pharmacology》1992,29(3):214-218
Summary Piroxicam, a nonsteroidal antiinflammatory drug, was given to 62 dogs bearing naturally occurring tumors in a phase I clinical trial. Dose escalation was performed, with oral doses ranging from 0.5 mg/kg every 48 h (q48h) to 1.5 mg/kg q48h being tested. Dose-limiting gastromestinal irritation/ulceration occurred in all four animals that received 1.5 mg/kg q48h. The maximum tolerated dose was 1 mg/kg q48h. Subclinical renal papillary necrosis occurred in two dogs (initial dosages, 1 and 1.5 mg/kg q48h, respectively). Following dose escalation, an additional group of dogs was treated with 0.3 mg/kg piroxicam q24h per os, the accepted canine dosage prior to this trial. Inclusion of this treatment group enabled evaluation of the toxicity of and tumor response to a daily dosage regimen. No complete remissions occurred in this trial. Partial remission was documented in three of ten dogs exhibiting transitional-cell carcinoma, in three of five animals bearing squamous-cell carcinoma, in one of three dogs displaying mammary adenocarcinoma, and in the one dog that exhibited a transmissible venereal tumor. The results of this study support the additional evaluation of piroxicam in a phase II clinical trial in dogs bearing naturally occurring tumors.This investigation was supported by Pfizer Inc. 相似文献
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59.
Gerald Gabriel 《医疗保健器具》2007,(10):65-65,67
事物的本质人类的智力是虚幻的,是难以受到约束的。甚至难以给它一个定义。智力可以用能力来解释吗?和记忆力有关吗?它和语言有关吗?还是数学?还是和上面的都有关系呢?只要你说你只是不能衡量智力,许多人会离去。为了使一个人 相似文献
60.
Gerald V. Goresky 《Journal canadien d'anesthésie》1994,41(7):655-655