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21.
We have developed a feedback-controlled bolus plus infusion (FC-B/I) method for monitoring the interaction between positron emission tomography (PET) ligands and their specific target molecules with PET. The usefulness of the FC-B/I method was evaluated by the direct interaction between [11C]raclopride, a dopamine D2 receptor (D2R) ligand, and cold raclopride (10 and 100 μg/kg) in the brains of conscious monkeys. The present results demonstrated that the FC-B/I method could achieve the equilibrium state of [11C]raclopride in the striatum of monkey brain, and also that the cold raclopride-induced reduction of [11C]raclopride binding to D2R was observed in a dose-dependent manner. Good correlations of distribution volume ratio of the striatum to cerebellum between the conventional bolus plus infusion (B/I) method and the FC-B/I method as well as between the conventional bolus injection method and the FC-B/I method were observed. These results indicated that the system could be a useful tool for the evaluation of interaction between drug candidates and their target molecules like enzymes, receptors, and transporters by using of their specific PET ligands.  相似文献   
22.
The tongue assumes an important role in bolus formation and transportation to the oropharynx and in retaining pharyngeal pressure during mastication and swallowing. Although the state of tongue-palate contact during swallowing is thought to change with bolus type, the details of these changes have yet to be clarified under normal physiological conditions. The purpose of this study was to examine the effect of bolus type on tongue pressure production against the hard palate during swallowing. Tongue pressures during swallowing 10 mL of water and 10 g of pudding and during dry swallow were measured with a sensor sheet system with five measurement points to evaluate normal physiological swallowing in 10 healthy dentate individuals. There was a common pattern in the sequential order of tongue pressure generation among the three swallowing conditions: tongue pressure was generated significantly earlier at the anterior-median part, followed by the posterior parts. During swallowing pudding and dry swallow, the duration of tongue pressure tended to increase at all channels except for the posterior-median part. The maximal magnitude of tongue pressure was significantly higher when swallowing pudding than when swallowing water at all channels except for the posterior-median part. The integrated value of tongue pressure was significantly higher when swallowing pudding than when swallowing water at all channels except for the posterior-median part. From these results, it was considered the tongue changed the sequential order, the duration and the magnitude of tongue pressure production according to the swallowing conditions (liquid swallowing, semisolid swallowing, dry swallow).  相似文献   
23.
Objective: To compare actual antibiotic use to the stratification based on the sepsis calculator in newborns with suspected early onset sepsis (EOS). To investigate differences in EOS risk and vital signs between newborns that received early (<12?h) versus late antibiotics (≥12?h of life).

Methods: Newborns born ≥34 weeks gestation in 2014 treated with antibiotics started within 72?h after birth were included. We calculated the risk per 1000 live births and retrospectively assigned each newborn to one of four recommended categories using the sepsis calculator.

Results: There were 2094 newborns, 111 (5.3%) received antibiotics and 108 newborns were included. The incidence of culture-proven EOS was 0.096%. In 57 newborns, the advice of the sepsis calculator was not to start antibiotic therapy. Antibiotic treatment was started early in 66 (61%) and late in 42 (39%) newborns. In the “late treatment” group, clinical condition deteriorated, including two newborns with culture-proven EOS. Tachypnea and respiratory distress were significantly more present.

Conclusion: Antibiotic use could be reduced by more than 50%. Newborns with initial low sepsis risk score clinically deteriorated beyond 12?h of life. Continuous good clinical observation remains very important. Prospective validation is necessary to evaluate the safety of this approach.  相似文献   
24.
目的:探讨静脉输注右关托咪定联合规律性间断硬膜外注射用于分娩镇痛的安全性及可行性.方法:选择2014年7~12月在我院产科接受硬膜外分娩镇痛的初产妇100例,随机分为两组:规律性间断硬膜外注射组(对照组)和右美托咪定联合规律性间断硬膜外注射组(右美托咪定组),每组50例.比较两组分娩镇痛期间生命体征的变化、分娩镇痛时间(T0~T4时)、第二产程时间、硬膜外药物消耗量、分娩方式、新生儿Apgar评分、镇痛前及镇痛后血浆儿茶酚胺的变化.结果:①两组产妇分娩镇痛期间平均动脉压(MBP)、视觉模拟评分(VAS)组间比较,差异无统计学意义(P>0.05);虽然右美托咪定组在T2和T4时的心率低于对照组(P<0.05),但在正常范围内.两组产妇分娩镇痛时间、分娩方式及新生儿Apgar评分比较,差异均无统计学意义(P>0.05).②右美托咪定组较对照组第二产程时间更短、硬膜外药物消耗量更少(P<0.05).③两组产妇实施分娩镇痛后血浆肾上腺素及去甲肾上腺素均明显下降,右美托咪定组下降幅度明显高于对照组(P<0.05).结论:静脉输注右美托咪定联合规律性间断硬膜外注射可安全及有效地应用于分娩镇痛,并能增强镇痛效能及利于阴道分娩.  相似文献   
25.
26.

目的 探讨程控硬膜外脉冲式输注不同剂量罗哌卡因复合舒芬太尼行阶梯式分娩镇痛对母婴的影响。
方法 选取拟经阴道分娩足月妊娠初产妇141例,年龄22~35岁,BMI 18.5~30.0 kg/m2,ASA Ⅰ或Ⅱ级,采用随机数字表法分为三组:对照组(C组)、阶梯式1组(S1组)和阶梯式2组(S2组),每组30例。三组均于L3-4椎间隙穿刺行硬膜外分娩镇痛,镇痛泵配方为0.08%罗哌卡因+0.5 μg/ml舒芬太尼。C组在分娩全程脉冲剂量为6 ml/h;S1组在宫口<3 cm时,脉冲剂量为6 ml/h,宫口≥3 cm时,脉冲剂量为8 ml/h;S2组在宫口<3 cm时,脉冲剂量为6 ml/h,宫口≥3 cm时,脉冲剂量为10 ml/h。记录宫口开3 cm、宫口开6 cm、宫口开全、分娩即刻产妇VAS疼痛评分。记录产程时间、镇痛泵按压次数、镇痛药使用总量、缩宫素使用情况、分娩方式、下肢运动功能(Bromage评分)及不良反应。胎儿脕出后,自全呼吸前,采集新生儿脐动脉血行血气分析,记录新生儿出生后1 min和5 min时Apgar评分。
结果 宫口开6 cm及宫口开全时S1组、S2组VAS疼痛评分明显低于C组,镇痛泵按压次数明显少于C组(P<0.05),且S2组VAS疼痛评分明显低于S1组,镇痛泵按压次数明显少于S1组(P<0.05);S1组、S2组第一产程和总产程时间均明显短于C组(P<0.05);S2组镇痛药使用总量明显少于C组,新生儿脐动脉Lac浓度明显低于C组(P<0.05)。三组缩宫素使用率、分娩方式、Bromage评分、不良反应及新生儿Apgar评分差异无统计学意义。
结论 采用程控硬膜外脉冲式输注罗哌卡因复合舒芬太尼行阶梯式分娩镇痛安全有效,且宫口≥3 cm时脉冲剂量10 ml/h镇痛效果更好,麻醉用药总量少,对母婴影响小。  相似文献   
27.

目的 探讨硬膜外间歇脉冲注入技术(PIEB)在产妇自控硬膜外分娩镇痛中的效果及对分娩结局的影响。
方法 选择行硬膜外分娩镇痛的单胎、头位、足月妊娠产妇100例,年龄18~38岁,BMI 20~32 kg/m2,ASA Ⅰ或Ⅱ级,采用随机数字表法分为两组:PIEB组和连续硬膜外输注组(CEI组),每组50例。两组镇痛药配方均为0.08%罗哌卡因+0.4 μg/ml舒芬太尼。PIEB组参数设置:脉冲频率每小时1次,剂量10 ml,注药速率400 ml/h,单次剂量10 ml,间隔20 min。CEI组参数设置:背景输注速率10 ml/h,单次剂量10 ml,间隔20 min。记录产妇分娩镇痛前、镇痛后1、2、3、5 h、宫口开全和分娩时的VAS疼痛评分;产妇首次按压时间、按压次数、镇痛泵用药总量、镇痛时间;总产程时间、产后出血量、新生儿Apgar评分、产妇对分娩镇痛效果满意度评分;感觉阻滞平面达T4的例数、改良Bromage评分;以及低血压、恶心呕吐等不良反应发生情况。
结果 与分娩镇痛前比较,分娩镇痛后两组产妇VAS疼痛评分明显降低(P<0.05)。与CEI组比较,PIEB组镇痛后2、3、5 h、宫口开全、分娩时VAS疼痛评分均明显降低(P<0.05),首次按压时间明显延迟(P<0.01),按压次数、镇痛泵用药总量明显减少(P<0.01)。与CEI组比较,PIEB组产妇满意度评分明显增高(P<0.01),感觉阻滞平面达T4的产妇比例明显升高(P<0.05)。两组总产程时间、产后出血量、新生儿Apgar评分差异无统计学意义。两组低血压和恶心呕吐等不良反应发生率差异无统计学意义。
结论 PIEB可安全有效地用于产妇自控硬膜外分娩镇痛,其效果优于连续硬膜外输注,产妇满意度高,且不影响分娩结局。  相似文献   
28.

Background

Prostate-specific antigen (PSA) testing has limited accuracy for the early detection of prostate cancer (PCa).

Objective

To assess the value added by percentage of free to total PSA (%fPSA), prostate cancer antigen 3 (PCA3), and a kallikrein panel (4k-panel) to the European Randomised Study of Screening for Prostate Cancer (ERSPC) multivariable prediction models: risk calculator (RC) 4, including transrectal ultrasound, and RC 4 plus digital rectal examination (4+DRE) for prescreened men.

Design, setting, and participants

Participants were invited for rescreening between October 2007 and February 2009 within the Dutch part of the ERSPC study. Biopsies were taken in men with a PSA level ≥3.0 ng/ml or a PCA3 score ≥10. Additional analyses of the 4k-panel were done on serum samples.

Outcome measurements and statistical analysis

Outcome was defined as PCa detectable by sextant biopsy. Receiver operating characteristic curve and decision curve analyses were performed to compare the predictive capabilities of %fPSA, PCA3, 4k-panel, the ERSPC RCs, and their combinations in logistic regression models.

Results and limitations

PCa was detected in 119 of 708 men. The %fPSA did not perform better univariately or added to the RCs compared with the RCs alone. In 202 men with an elevated PSA, the 4k-panel discriminated better than PCA3 when modelled univariately (area under the curve [AUC]: 0.78 vs 0.62; p = 0.01). The multivariable models with PCA3 or the 4k-panel were equivalent (AUC: 0.80 for RC 4+DRE). In the total population, PCA3 discriminated better than the 4k-panel (univariate AUC: 0.63 vs 0.56; p = 0.05). There was no statistically significant difference between the multivariable model with PCA3 (AUC: 0.73) versus the model with the 4k-panel (AUC: 0.71; p = 0.18). The multivariable model with PCA3 performed better than the reference model (0.73 vs 0.70; p = 0.02). Decision curves confirmed these patterns, although numbers were small.

Conclusions

Both PCA3 and, to a lesser extent, a 4k-panel have added value to the DRE-based ERSPC RC in detecting PCa in prescreened men.

Patient summary

We studied the added value of novel biomarkers to previously developed risk prediction models for prostate cancer. We found that inclusion of these biomarkers resulted in an increase in predictive ability.  相似文献   
29.
30.
目的探讨遥控骨水泥推注装置在经皮球囊扩张椎体后凸成形术(PKP)中的作用与临床效果。方法回顾分析自2010—07—2012—03收治的骨质疏松性椎体压缩骨折75例.在PKP中应用遥控骨水泥推注装置可匀速推注骨水泥,防止骨水泥渗漏,同时明显减少手术医生在X线下的暴露时间。结果75例术后经6~12个月随防(平均10个月),所有患者术后腰背痛视觉模拟评分(VAS)均较术前明显改善(P〈O.01)。未使用遥控骨水泥推注装置时手术医生在X线下暴露30~50次,接受约1000mSvX线射线,使用遥控骨水泥推注装置后术者在X线下暴露lO~15次,接受约300mSvX线射线,明显缩短术者在X线下的暴露时间。手术过程未发生骨水泥渗漏、脊髓损伤。结论PKP治疗骨质疏松性椎体压缩骨折具有创伤小、恢复快的优点,配合使用遥控骨水泥推注装置可使骨水泥匀速缓慢推注,有效防止骨水泥渗漏.明显减少手术医生在X线下的暴露时间.有较高的临床应用价值。  相似文献   
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