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171.
J. M. McGree J. A. Eccleston S. B. Duffull 《Journal of pharmacokinetics and pharmacodynamics》2009,36(2):101-123
We consider nested multiple response models which are used extensively in the area of pharmacometrics. Given the conditional
nature of such models, differences in predicted responses are a consequence of different assumptions about how the models
interact. As such, sequential versus simultaneous and First Order (FO) versus First Order Conditional Estimation (FOCE) techniques
have been explored in the literature where it was found that the sequential and FO approaches can produce biased results.
It is therefore of interest to determine any design consequences between the various methods and approximations. As optimal
design for nonlinear mixed effects models is dependent upon initial parameter estimates and an approximation to the expected
Fisher information matrix, it is necessary to incorporate any influence of nonlinearity (or parameter-effects curvature) into
our exploration. Hence, sequential versus simultaneous design with FO and FOCE considerations are compared under low, typical
and high degrees of nonlinearity. Additionally, predicted standard errors of parameters are also compared to empirical estimates
formed via a simulation/estimation study in NONMEM. Initially, design theory for nested multiple response models is developed
and approaches mentioned above are investigated by considering a pharmacokinetic–pharmacodynamic model found in the literature.
We consider design for situations where all responses are continuous and extend this methodology to the case where a response
may be a discrete random variable. In particular, for a binary response pharmacodynamic model, it is conjectured that such
responses will offer little information about all parameters and hence a sequential optimization, in the form of product design
optimality, may yield near optimal designs. 相似文献
172.
目的探讨左半结肠癌急性梗阻Ⅰ期切除吻合的Ⅰ临床应用价值。方法对1988年1月至2006年12月24侧实施左半结肠癌急性梗阻Ⅰ期切除吻合手术患者的资料进行回顾性总结。结果24例均未发生吻合口漏,仅3例发生切口感染,经局部换药处理Ⅱ期愈合。结论积极的术前准备、术中彻底的肠减压能为左半结肠癌急性梗阻Ⅰ期切除吻合提供安全保证. 相似文献
173.
Ashwin A Kallianpur Rajinder Parshad Maya Dehran Priya Hazrah 《JSLS, Journal of the Society of Laparoendoscopic Surgeons》2007,11(2):229-234
BACKGROUND AND OBJECTIVES: Feasibility of ambulatory laparoscopic inguinal hernia repair in developing countries is not known due to lack of dedicated outpatient centers. This study prospectively evaluated the feasibility of outpatient discharge after laparoscopic total extraperitoneal inguinal hernia repair done in combination with in-hospital services and its impact on quality of life. METHODS: Forty patients were studied who had uncomplicated inguinal hernias and fulfilled the selection criteria. Quality of life was evaluated by using the SF-12 questionnaire. RESULTS: Ninety percent of patients could be discharged as outpatients. Four patients required admission. No major complications or readmissions occurred. Physical components of quality of life deteriorated in the immediate postoperative period but improved to above preoperative levels within one month. A transient deterioration in subgroups of the mental health component was observed, which recovered to normal in less than a week. There was no significant alteration in the emotional component. There has been no recurrence at a median follow-up of 25 months. CONCLUSION: It was feasible to safely perform outpatient TEP in combination with routine in-hospital services without increasing complications or causing any adverse impact on quality of life. This was possible subject to adherence to proper selection and discharge criteria. 相似文献
174.
Treatment strategy for synchronous metastases of colorectal cancer: is hepatic resection after an observation interval appropriate? 总被引:1,自引:1,他引:0
Yasuhiro Shimizu Kenzo Yasui Tsuyoshi Sano Takashi Hirai Yukihide Kanemitsu Koji Komori Tomoyuki Kato 《Langenbeck's archives of surgery / Deutsche Gesellschaft fur Chirurgie》2007,392(5):535-538
Background In cases of synchronous colorectal hepatic metastases, the primary colorectal cancer strongly influences on the metastases.
Our treatment policy has been to conduct hepatic resection for the metastases at an interval of 3 months after colorectal
resection. We examined the appropriateness of interval hepatic resection for synchronous hepatic metastasis.
Materials and methods The subjects were 164 patients who underwent resection of hepatic metastasis of colorectal cancer (synchronous, 70 patients;
metachronous, 94 patients). Background factors for hepatic metastasis and postoperative results were compared for synchronous
and metachronous cases.
Results The cumulative survival rate for 164 patients at 3, 5, and 10 years postoperatively was 71.9%, 51.8%, and 36.6%, and the post-resection
recurrence rate in remnant livers was 26.8%. Interval resection for synchronous hepatic metastases was conducted in 49 cases
after a mean interval of 131 days. No difference was seen in postoperative outcome between synchronous and metachronous cases.
Conclusion The outcome was similarly favorable in cases of synchronous hepatic metastasis and in cases of metachronous metastasis. Delaying
resection allows accurate understanding of the number and location of hepatic metastases, and is beneficial in determining
candidates for surgery and in selecting surgical procedure. 相似文献
175.
目的 研究h-BMP-2基因转染骨髓间充质干细胞(BMSCs)在复合煅烧骨、β-TCP或直接植入裸鼠股部后的成骨能力。方法 通过影像学、组织学和形态计量学等方法,观察未经诱导、OS液诱导和h-BMP-2基因转染BMSCs在复合煅烧骨,或多孔β-TCP后植入裸鼠皮下,或直接制成细胞悬液注入,在4、8、12周诱导成骨和材料降解情况。结果 在裸鼠皮下,单纯生物陶瓷不能诱导成骨,而复合了未诱导、OS液诱导和h-BMP-2基因转染BMSCs的生物陶瓷均能成骨,成骨量为h-BMP-2基因转染组>OS液诱导组>未经诱导组(P<0.05),B-TCP可随骨长入而降解;注入裸鼠肌肉的OS液诱导的和h-BMP-2转染的BMSCs均能诱导成骨,而未经诱导MSCs则不能成骨。结论 复合人BMP基因转染BMSCs的β-TCP是一种理想的骨修复材料。 相似文献
176.
177.
Massimo Porena Sauro Biscotto Elisabetta Costantini Ettore Mearini Livio Verdini 《Neurourology and urodynamics》2003,22(3):206-222
AIMS: The aim of this study is to compare PUMA curves with different pathologic conditions causing bladder dysfunction in 158 men and 83 women. METHODS: PUMA results in terms of bladder outlet obstruction and detrusor contractility were compared in 92 men with benign prostatic hypertrophy (BPH) and p(ves) congruent with p(det) (i.e., p(abd) congruent with 0) with the results of the urodynamics operator's opinion, the provisional International Continence Society method, Abrams and Griffith's diagram, urethral resistence factor (URA), Sch?fer's diagram, and Watt factor. PUMA curves correlated reliably with different pathologic conditions such as obstructive BPH, orthotopic bladder, cystocele, the neurological bladder, and bladder diverticulum. Statistical analysis indicated excellent agreement between PUMA and URA; agreement with other methods was good in cases of obstruction and nonobstruction. In doubtful cases, as diagnosed by standard methods, PUMA agreed only with the Abrams and Griffith's diagram. PUMA and Wmax were in good agreement on detrusor con traction force. Agreement between PUMA and Sch?fer's diagram was excellent for patients with detrusor hypercontractility and good for patients with detrusor hypocontractility and normocontractility. PUMA is the only method applicable to women. It is easy to perform. When integrated with other diagnostic tests, it provides realistic data for diagnosis, medical or surgical therapy, and outcome. 相似文献
178.
179.
目的 揭示大脑中动脉闭塞(MCAO)后丘脑钙调磷酸酶(CaN)的时空变化规律,探讨CaN的作用机制。方法 制备大鼠大脑中动脉永久性闭塞模型,分别测定缺血后不同时间点病灶侧丘脑CaN的活性和含量。结果 缺血后24h始丘脑CaN的含量下降且不恢复;CaN的活性在缺血后2h和4h减弱,6h始恢复至正常水平。可见,CaN的活性与含量分离。结论 大脑中动脉闭塞后丘脑CaN活性独特的时间变化规律显示其参与介导继发性丘脑损伤,可能具有毒性作用。 相似文献
180.
目的:探讨靶重建放大扫描技术对肺孤立性结节病变的诊断价值。方法:对63例患者先行常规CT平扫,选定结节处为兴趣区,行薄层靶重建放大扫描,层厚、层距为2mm,FOV为160。结果:42例恶性病变中有37例表现为深分叶,占88.1%;21例良性病变中有15例表现为浅分叶,占71.4%。恶性结节中15例内部出现条状低密度支气管征;7例出现血管集中征;8例出现空泡征;病变内部出现液化坏死13例,其中恶性病变ll例。22例出现钙化,包括12例良性病变和10例恶性病变。2例错构瘤内均见小面积脂肪性低密度影。结论:靶重建放大扫描比普通CT扫描可提供更多的信息,对良恶性病变的鉴别诊断有一定价值。恶性病变大多数为深分叶,良性病变大多数为浅分叶或无分叶。 相似文献