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41.
本文报道NIDDM患者在常规治疗的基础上加用钙剂和维生素D治疗后的钙代谢变化。糖尿病患者单纯用常规治疗控制血糖后,负钙平衡不能完全纠正,而加用钙剂和维生素D治疗后,负钙平衡能完全纠正,并且高于正常对照组平衡值(P<0.01)。说明钙剂加维生素D治疗对糖尿病性骨质疏松是有益的。  相似文献   
42.
目的 观察腹腔镜胆囊切除术 (LaparoscopicCholecystectomy ,L .C)后钛夹在腹腔内异位。方法 前瞻性对2 0 0 2年 1~ 5月间 6 0例L .C病人进行追踪观察临床表现 ,采用B超、腹部X线检查等方法 ,观察钛夹位置的变化与肝外胆管的关系。结果  6 0例L .C后病人中 5例钛夹发生位置改变。结论 ①钛夹在体内 ,对胆道无压迫、无胆漏 ;②观察钛夹异位 ,以采用B超为最简单、经济的方法。  相似文献   
43.
BACKGROUND AND PURPOSE: The potential risk of prolongation of treatment time in cervical cancer has been reported for many low-dose rate (LDR) studies, with an estimated loss of local control ranging from 0.3 to 1.6% per day of treatment prolongation. Since the treatment schedule for fractionated high-dose rate intracavitary brachytherapy (HDRICB) is not directly comparable with that for low-dose rate studies, this report aims to evaluate the adverse effect of treatment prolongation specifically for cervical cancer treated with HDRICB. MATERIAL AND METHODS: From September 1992 to December 1997, 257 patients diagnosed with uterine cervical cancer (35 Ib, 26 IIa, 122 IIb, 10 IIIa, 57 IIIb, 7 IVa), who underwent external radiotherapy combined with between two and four courses of HDRICB and a minimum of 3 years of follow-up (median 57 months), were analyzed. Treatment consisted of irradiation of the whole pelvis with 44-45 Gy consisting of 22-25 fractions by 5 weeks, with the dose boosted to 54-58 Gy (with central shielding) for patients diagnosed as FIGO stage IIb-IVa bilateral parametrial disease. HDRICB was performed using an Ir-192 remote afterloading technique at 1-week intervals. The standard prescribed dose for each course of HDRICB was 7.2 Gy to point A for three insertions (before July 1995), or 6.0 Gy to point A for four insertions (after July 1995). Total prescribed point A doses (external beam radiotherapy+HDRICB) ranged from 58 to 71.6 Gy (median, 65.6 Gy) for stage IB-IIA, while analogous dosage for larger lesions (stage IIb-IVa) ranged from 59 to 75.6 Gy (median, 65.6 Gy). Kaplan-Meier and multivariate analyses were used to test the effect of treatment time on pelvic control rate (PCR) and cause-specific survival (CSS) at 5 years. RESULTS: Median treatment time was 63 days. For all stages of disease, the 5-year CSS and PCR were significantly different comparing treatment times of less than and greater than or equal to 63 days [83% and 65% (P=0.004], 93% and 83% (P=0.02), respectively]. These associations were also significant for stage Ib/IIa [97% and 79% (P=0.01), and 100% and 87% (P=0.02), respectively), but not for stage IIb [75% and 72% (P=0.79), and 93% and 87% (P=0.83), respectively] or stage III [66% and 49% (P=0.2), and 83% and 72% (P=0.21), respectively]. Multivariate analysis identified three prognostic factors for CSS, stage (P<0.001), tumor response to external RT (P=0.001), and overall treatment time (OTT; P=0.006). Prognostic factors for pelvic failure were stage (P<0.001), tumor response to external RT (P=0.001), and OTT (P=0.03). Prolongation of treatment time resulted in a daily decrease in pelvic control rate of 0.67% overall, and 0.43% for stage Ib-IIa, 0.57% for stage IIb, and 0.73% for stage III patients. CONCLUSION: Analysis of the data from the current study demonstrates that the adverse effect of treatment prolongation was observed later in the treatment course for the high-dose rate (HDR) series compared to the LDR analog, however, treatment-time prolongation still negatively influenced the cause-specific survival and pelvic control rate for both dosage groups.  相似文献   
44.
目的应用超声多普勒方法评价冠心病患者的左室整体舒张功能及舒张功能障碍的发生率,探讨舒张功能障碍在冠心病无创诊断中的价值。方法对入选病人行常规检查,同时进行二尖瓣血流频谱、肺静脉血流频谱及二尖瓣环组织多普勒检查,对比临床标准与舒张功能障碍标准对冠心病的诊断率。结果舒张功能障碍标准对冠心病的检出率显著高于临床标准。结论舒张功能检查可作为冠心病诊断的初筛检查。  相似文献   
45.
Background  High-quality attenuation maps are critical for attenuation correction of myocardial perfusion single photon emission computed tomography studies. The filtered backprojection (FBP) approach can introduce errors, especially with low-count transmission data. We present a new method for attenuation map reconstruction and examine its performance in phantom and patient data. Methods and Results  The Bayesian iterative transmission gradient algorithm incorporates a spatially varying gamma prior function that preferentially weights estimated attenuation coefficients toward the soft-tissue value while allowing data-driven solutions for lung and bone regions. The performance with attenuation-corrected technetium 99m sestamibi clinical images was evaluated in phantom studies and in 50 low-likelihood patients grouped by body mass index (BMI). The algorithm converged in 15 iterations in the phantom studies. For the clinical studies, soft-tissue estimates had significantly greater uniformity of mediastinal coefficients (mean SD, 0.005 cm−1 vs 0.011 cm−1; P<.0001). The accuracy and uniformity of the Bayesian iterative transmission gradient algorithm were independent of BMI, whereas both declined at higher BMI values with FBP. Attenuation-corrected perfusion images showed improvement in myocardial wall variability (4.8% to 4.1%, P=.02) for all BMI groups with the new method compared with FBP. Conclusion  This new method for attenuation map reconstruction provides rapidly converging and accurate attenuation maps over a wide spectrum of patient BMI values and significantly improves attenuation-corrected perfusion images.  相似文献   
46.
Background: Chronic pain models are commonly defined as either nerve-injury or inflammation models, but recent work suggests inflammatory processes are important in nerve injury-induced pain.

Methods: In the rat spinal nerve ligation model, the authors examined effects of systemic corticosteroid triamcinolone acetonide (TA) on the cytokine protein profile and sympathetic sprouting in the axotomized sensory ganglia, excitability of sensory neurons, and mechanical sensitivity.

Results: By postoperative day 3, marked increases (5- to 16-fold) in monocyte chemoattractant protein-1, growth-related oncogene (GRO/KC or CXCL1), and interleukin (IL)-6 were observed, whereas IL-4 and IL-2 levels fell more than fourfold. The increased cytokines and number of sympathetic basket formations in the sensory ganglia were reduced toward normal values by TA given starting at the time of injury. Interleukin-4 and IL-2 levels were not restored by TA. Systemic TA also reduced the firing rate and incidence of bursting activity, but not the overall incidence of spontaneous activity, in large- and medium-sized neurons. Mechanical hypersensitivity on postoperative day 3 was reduced by TA, and some effect could still be observed 4 days after cessation of TA. However, starting TA at day 7 was ineffective.  相似文献   

47.
Estrogen receptors in the external anal sphincter   总被引:1,自引:0,他引:1  
Inasmuch as anal competence in women is reduced after the age of 50 years, it may be dependent on effects of estrogens. In this study, samples of the external anal sphincter were analyzed for the presence of estrogen receptors and were found to be present at a median concentration of 5.0 fmol per milligram of protein (range, 1.9 to 13) in women (n = 7), and 1.1 fmol per milligram of protein (range, 0 to 3.2) in men (n = 7). These findings are of interest with regard to the treatment of idiopathic anal incontinence.  相似文献   
48.
评价了PPV系列衍生物的电学性质、非线性光学性质及其应用。  相似文献   
49.
目的 :探讨胫腓骨远端骨折治疗术式的选择、术中术后应注意的问题及其疗效。方法 :对不同类型的胫腓骨远端骨折 36例进行 8~ 18个月的随访 ,并结合临床及影像学资料 ,对其诊断、手术方法及治疗效果进行分析总结。结果 :本组术后 2 5~ 3 5个月骨折均愈合。踝关节功能优良率 77 7%。结论 :熟悉骨折的分型及相应内固定术式的选择 ;注重踝穴骨折的解剖复位及固定和踝关节的功能位固定及早期功能锻炼。  相似文献   
50.
An effective “suicide gene” therapy strategy in experimental studies has been the use of the herpes simplex virus thymidine kinase gene(HSV-tk) to sensitize tumors to the cytotoxic effects of ganciclovir administration. Previous studies using this model have focused on utilizing maximal viral titers and high levels of ganciclovir that are not compatible with human dosing. Because of the high ganciclovir doses and the maximal viral titers, this strategy has limited application to actual clinical scenarios. In the following studies the authors investigate tumor regression in an oral squamous cell carcinoma animal model as a function of variable adenoviral titers and more physiologic ganciclovir dosing. Using adenoviral titers ranging from 1 × 108 to 2 × 109 plaque forming units(pfu) to treat oral tumors, they found no statistical difference in tumor regression among the different viral doses, despite differences in mitotic activity. Each treatment group, however, demonstrated a significant effect on tumor regression when compared with controls. Furthermore, the authors were able to reduce the level of ganciclovir administration to 10 mg/kg twice daily from established levels of 100 to 150 mg/kg twice daily while maintaining significant tumor responses to the HSV-tk therapy. Mean survival of animals treated with this lower ganciclovir dose was significantly higher than in controls and was equal to established means based on previous studies using higher ganciclovir doses. The optimization of this suicide gene therapy strategy is imperative in order to minimize theoretical and known viral and ganciclovir toxicities while establishing a foundation upon which to design appropriate and effective clinical trials.  相似文献   
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