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31.
目的研究妊高征孕妇心率变异性(HRV)、血压变异性(BPV)和压力反射敏感性(BRS)的改变.方法用无创伤测定和频谱分析方法,检测31名正常妊娠孕妇和19名中、重度妊高征孕妇的HRV、BPV和自发性BRS,数据用SPSS 10.0软件分析.结果妊高征组和正常妊娠组相比,HRV各指标有下降趋势,但无统计学意义(P>0.05).妊高征孕妇BPV的低频成分显著高于正常妊娠孕妇(P<0.05),BRS较正常妊娠孕妇降低(P<0.05).结论妊高征孕妇交感神经对血压调节的活动性较正常妊娠孕妇增强;压力反射功能受损可能是妊高征发病过程中一重要环节.  相似文献   
32.
Systemic toxicity after significant dermal exposure to hydrofluoric acid includes rapid development of hypocalcemia and hyperkalemia, leading to ventricular fibrillation. Similar dysrhythmias have occurred in patients after ingestion of sodium fluoride-containing compounds. Ingestion of hydrofluoric acid could induce similar cardiac toxicity; however, reported cases of hydrofluoric acid ingestion rarely have been described, and the rapid death of these patients has not allowed verification of this hypothesis. On two separate occasions, a 70-year-old woman ingested up to 2 oz of a 8% hydrofluoric acid-containing solution. Recurrent ventricular fibrillation with concurrent hypocalcemia and hypomagnesemia complicated her first episode, whereas a more aggressive administration of calcium and magnesium may have prevented dysrhythmias in the second episode. Survival from ventricular fibrillation after hydrofluoric acid ingestion has not been reported previously and suggests a role for aggressive empiric calcium and magnesium replacement.  相似文献   
33.
34.
四环素抑制胶原酶活性   总被引:5,自引:0,他引:5  
王一  陈少军 《眼科研究》1995,13(1):19-20
对常用四种抗生素的抑活胶原酶作用进行了体外实验观察,结果表明,氯霉素,庆大霉素,青霉素对胶原酶活性无抑制作用,而四环素则显著抑制胶原酶活性,且抑活作用与浓度成正比。  相似文献   
35.
Objective To evaluate the bioequivalence between recombinant human growth hormone (rhGH) for reconstitution, and two dosages of liquid formulation of rhGH [ (151U) 5mg or (301U) lOmg per 3ml ]. Methods The study drugs were tested in a randomized, single-blind and three-period crossover studies in 24 healthy male subjects. The three drugs were administered by subcutaneous injection at a dose of O. 21U/kg body weight. A continuous somatostatin infusion was given in order to suppress the secretion of endogenous GH. The ve- nous blood samples were drawn at different time points to test the serum concentration of GH. The pharmacokinetic parameters were analyzed by statistical methods. Results 90% confidence intervals (CI) of AUC0-24h among three products were all within 80% - 125% interval ( 103. 4% - 116. 5%, 105. 7% - 119. 6% and 91.9% - 103. 7%, respectively), and the Cls of C,~ among three products were all within 70% - 143% interval (91.9% - 114. 0%, 103. 7% -127. 2% and 81.6% -97. 4%, respectively). There was no statisitical difference of tmax among all the three products. Conclusion These data demonstrate that there is bioequivalence between rhGH for reconstitution and two liquid formulations of rhGH.  相似文献   
36.
克罗米芬兴奋试验预测卵巢储备功能的价值   总被引:1,自引:0,他引:1  
目的探讨克罗米芬兴奋试验(CCT)在不孕妇女中预测卵巢储备功能的作用。方法对2001年1月至2005年2月就诊于广东省妇幼保健院的666例不孕症患者作为研究对象,分为A组(≥35岁)461例为高龄组,B组(〈35岁)205例为低龄组,另取156例年龄〈35岁、非女方不孕原因者作为对照组,对三组受试者进行CCT。结果CCT异常发生率A组、B组及对照组分别为27.76%、34.14%、2.56%,A组及B组与对照组比较差异均有非常显著性意义(P〈0.01)。基础卵泡刺激素(FSH)〈10IU/L、雌二醇(E2)〈180pmot/L的不孕患者CCT异常发生率分剐为17.46%、24.19%,均明显低于FSH≥10IU/L、E2≥180pmol/L患者的64.19%及39.4%(P〈0.01)。结论CCT预测卵巢储备功能较基础FSH更敏感,CCT可作为常规了解卵巢储备功能的一项检测方法。  相似文献   
37.
PURPOSE: The aim of this retrospective study was to analyze the characteristics of delayed panfacial fractures and evaluate treatment results. PATIENTS AND METHODS: Thirty-three patients with delayed panfacial fractures were treated in the Maxillofacial Trauma Center of Peking University, School and Hospital of Stomatology between 1998 and 2004. Each patient was examined by computed tomography (CT) scans before operation. For those who had no severe opening restriction, dental impressions were taken to fabricate dental casts. For those with severely comminuted fractures, 3-dimensional (3D) models of the facial skeleton were used. Re-establishing the continuity of the mandible was the first step and then used as a platform to reconstruct the maxillary fractures via maxillomandibular fixation after Le Fort I osteotomy. The third step was to restore the mid- and upper-facial width and projection by coronal approach to expose the zygomatic complex and frontal bone/sinus and/or naso-orbito-ethmoid (NOE) fractures. RESULTS: There were 3 types of mandibular fractures that affected the treatment plan: 1) type I, mandibular body/symphysis fracture(s) (17/33, 51.52%); 2) type II, mandibular angle and/or condylar fracture(s) (6/33, 18.18%); and 3) type III, both mandibular body/symphysis and angle/condylar fractures (10/33, 30.30%). Fourteen cases were associated with NOE fractures (42.42%) and 3 cases had frontal sinus fractures (9.1%). Twelve cases had enophthalmos (36.36%) and 3 lost 1 eyeball. The order of treatment was dependent on the mandibular fracture type. For type I fractures, reconstructing the mandibular arch was the first step. For type II fractures, repairing the angle, ascending rami, and condylar areas was the first step. For type III fractures, when both mandibular height and arch were disrupted, freeing the malunited angle or condyle was the first step before restoring the mandibular arch form. Reconstruction of the mandibular height and projection was then carried out. For all 3 types, the second step was to restore the mid- and upper facial width and projection by reducing the zygomatic complex and frontal bone/sinus or NOE fractures. Maxillary fixation across the Le Fort I level was the last step. Le Fort I osteotomy was used for all 33 cases. Bone grafts and soft tissue suspension also were used. Twenty-one cases (63.64%) had good results, 7 (21.21%) cases were acceptable, and 5 (15.15%) were not good. There were 7 cases (21.21%) that still had soft tissue problems that needed secondary operations. CONCLUSIONS: Reconstruction of the mandible first with Le Fort I osteotomy is a good way to treat delayed panfacial fractures. Computed tomography and 3D CT, model surgery, and occasionally 3D models are necessary aids for diagnosis and treatment. Soft tissue problems, including lacerations and asymmetries, were often the factors that caused an unfavorable outcome.  相似文献   
38.
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   
39.
A sciatic nerve lesion is uncommon. We report the utility of the endoscope in an 18-year-old female with multiple lesions of her sciatic nerve. Somatosensory evoked potentials and MRI were indicative of a sciatic nerve lesion. We describe a simple technique of endoscopic exploration of the sciatic nerve to assist intraoperative decision making.  相似文献   
40.
目的:观察异丙酚加喉上神经阻滞用于纤支镜检查期间,患对操作刺激反应、耐受程度以及对心血管反应和遗忘程度。方法:选40例拟诊肺癌患行ASAⅡ~Ⅲ纤支镜检查,喉上神经阻滞成功后推注0.5~1mg/kg异丙酚,患意识消失后,进行纤支镜操作。结果:所有病人都能耐受检查。术中收缩压、舒张压、心率、血氧饱和度等无明显影响,无恶心、呕吐等并发症,大大减轻了检查对病人带来的痛苦。结论:异丙酚加喉上神经阻滞用于纤支镜检查,对呼吸、循环影响小,能减轻病人痛苦,术后具有遗忘作用,值得推广。  相似文献   
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