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51.
Objective: At present, only limited data are available on endometrial volume during the menstrual cycle. Most of these studies deal with animal models and use magnetic resonance imaging for volume measuring. The application of three-dimensional ultrasound in endometrial volume estimation is the subject of this study.Setting: Patients visiting the outpatient unit of the division of endocrinology and reproductive medicine of a university hospital.Patient(s): Twenty patients with a history of a normal menstrual cycle were selected.Intervention(s): Ultrasound examinations were performed during a single menstrual cycle in addition to routine laboratory tests.Main Outcome Measure(s): Uterus-endometrial volume ratio.Result(s): Data from 18 patients could be evaluated. In 81 examinations the endometrium volume could be determined. Mean endometrial volume measured by three-dimensional ultrasound was 1.23 cm'. Mean uterus volume was 48.93 cm3. The change of the uterus-endometrial volume ratio showed a good correlation with the day of menstrual cycle. Quadratic regression analysis of volume and cycle length was R2 = 0.432.Conclusion(s): Three-dimensional ultrasound allows assessment of volume data of the female internal genitalia. In this study changes of the endometrial volume in menstrual cycles were measured. Additional studies are required to give information on the clinical impact of this new technique of endometrial volume estimation.  相似文献   
52.
Pelvic ultrasonography in normal girls and in girls with pubertal precocity   总被引:6,自引:0,他引:6  
This prospective study sought to evaluate the role of pelvic ultrasonography in differentiating between various types of pubertal precocity. A control group of 117 normal girls (aged 1.1-15.6) was studied and compared with 87 girls with premature sexual maturation (aged 1.1-9.2y). Of these patients 19 had central precocious puberty (CPP), 48 had isolated premature thelarche (IPT) and 20 had premature adrenarche (IPA) Pelvic ultrasound variables evaluated were: (i) uterus: longitudinal diameter (uterine length), cross-sectional area (CSA) and fundo-cervical ratio; and (ii) ovaries: volume and morphology. Ovarian morphology was subdivided in 6 different appearances: solid, microcystic, paucicystic, multicystic, macrocystic, and major isolated cyst. In normal control girls, uterine length and CSA increased with age, although no cut-off values could be defined between different age ranges, and they were correlated with breast stage; fundo-cervical ratio was stable through childhood and increased after age 9. Ovarian volume was significantly greater in pubertal girls with breast stage 2 than in those with only pubic and/or axillary hair. There was a clear predominance of solid ovarian appearances in the age range 2-7, with the multicystic appearance being seen only after age 7, a minority being macrocystic. After age 10 all the different patterns were observed, and after age 13 the frequency of a macrocystic pattern increased. Significantly more mature ovarian appearances were observed in subjects with breast development compared with those without, independently of the presence of pubic hair. Patients with IPT had no significant differences in pelvic ultrasound measurements when compared with age-matched controls. All the different morphological ovarian appearances were observed in IPT, in contrast to age-matched controls, where only the less mature patterns (solid, micro- and paucicystic) were seen. Patients with CPP had significantly more mature patterns of ovarian morphology compared with age-matched controls, but did not differ from pubertal pre-menarcheal controls. Those patients with IPA differed from age-matched controls only in having significantly greater uterine length and CSA. Comparison of the pelvic ultrasound parameters between patient groups (IPT, CPP, IPA) and age-matched controls revealed significantly higher values in CPP for uterine length, uterine CSA and ovarian volume. Ovarian volume was also greater in IPT than in IPA. Ovarian morphology was significantly different in patients (IPT, CPP, IPA) compared with age-matched controls, but none of the ovarian morphological appearances was exclusive to a single condition. In conclusion: (i) pelvic ultrasound parameters increase progressively from birth to maturity, but no clear cut-off values can be established between age ranges; (ii) pelvic ultrasound variables reach adult values during puberty, with differences in the timing that may reflect geographical variations; (iii) the multicystic ovarian appearance occurs just before the onset of puberty; (iv) pelvic ultrasonography cannot always differentiate clearly between different disturbances of puberty and therefore cannot supersede other observations and investigations in the evaluation of pubertal disorders; and (v) in this study we propose a more detailed pelvic ultrasound terminology that can avoid apparent confusion in defining ovarian ultrasound appearance.  相似文献   
53.
To determine the effects of animal and artificial surfactants on cerebral haemodynamics, 20 premature babies receiving mechanical ventilation were randomized to receive Curosurf or Exosurf surfactant. Anterior cerebral artery blood flow velocity (CABFV) was measured using Doppler ultrasound before and up to 2 h after treatment. Following animal surfactant there was a rapid reduction in CABFV (median -36%, range -43% to +8%, p < 0:01), whereas artificial surfactant resulted in a slower rise which was less marked (median +20%, range -7% to +62%, p < 0:05). There were no significant changes in blood pressure. Two hours after administration, the oxygenation index (OI) improved significantly only in babies receiving animal surfactant. In this group there was a significant association between the change in CABFV at 1 min and the change in OI at 2 h ( r = 0:66, p < 0:05). Animal surfactant produces rapid improvements in ventilation which are associated with marked alterations in cerebral haemodynamics.  相似文献   
54.
彩色多普勒组织显像在小儿病毒性心肌炎诊断中的应用   总被引:3,自引:0,他引:3  
本文报告用彩色多普勒组织显像(DTI)测定正常小儿173名,病毒性心肌炎40例,发现DTI在正常小儿的规律。病毒性心肌炎二尖瓣环舒张早期运动速度(MVR-DeV)显著低于正常儿童,40例病毒性心肌炎MVR-DeV降低者占72.5%,经过治疗后MVR-DeV90%以上短期内恢复正常。MVR-DeV降低率显著高于心脏解剖、心功能、心脏血流参数、心电图和心肌酶的异常率。因此,MVR-DeV对病毒性心肌炎的诊断、病情了解以及疗效观察均有重要价值。  相似文献   
55.
The cytotoxic and anti-proliferative effects of high-energy pulsed ultrasound (HEPUS) on human squamous cell carcinoma cells cloned from the hypopharynx (FaDu) and benign connective tissue cells (fibroblasts) were investigated in vitro. Sonication was carried out using an experimental piezoelectric, self-focusing burst-signal transducer. To increase the induction of cavitation, the transducer used was specifically designed to produce multiple oscillations with a high negative pressure amplitude. In both cell lines tested, the application of 100, 800 and 2000 pulses resulted in a high reduction of vital cells. After 2000 pulses, 4.0 ± 1.1% of the fibroblasts but only 2.0 ± 0.4% of the FaDu cells survived HEPUS exposure. A postexposure inhibiting effect of HEPUS for 10 days on the proliferation of surviving cells was noted for the FaDu cells exposed to 2000 pulses, but not as much for the fibroblasts. These findings support the hypothesis that human squamous cell carcinoma cells of the hypopharynx might be more sensitive to HEPUS than fibroblasts and that total tumor cell ablation might be possible in vitro given a sufficient number of HEPUS pulses. Received: 18 November 1997 / Accepted: 21 April 1998  相似文献   
56.
血清CA125结合B超对绝经后妇女卵巢恶性病变的预测价值   总被引:1,自引:0,他引:1  
目的 通过了解绝经后妇女卵巢肿物的临床特点,探讨早期发现绝经后妇女卵巢恶性肿瘤的可行方法。方法 回顾分析302例经手术后病理证实为卵巢肿物的自然绝经后妇女的临床特点,采用B超结合血CA125的定量测定。结果 71.2%的绝经后卵巢肿物患者无自觉症状,38.7%为卵巢恶性肿瘤,BUS结合血CA125对卵巢恶性病变预测的敏感性为98.4%,特异性为57.9%,阳性预测值62.6%,阴性预测值98.1%。结论 对绝经后妇女实施妇科检查及B超的筛查结合血CA125的定量测定,有助于临床医生及时发现卵巢恶性肿瘤。  相似文献   
57.
OBJECTIVES: To investigate the impact of an ultrasound dating service on obstetric services. METHODS: A prospective trial with 3009 unselected women presenting for antenatal care at two Midwife Obstetric Units in a socioeconomically deprived urban area, South Africa. In the study unit, student ultrasonographers provided a basic ultrasound service. In the control unit, obstetric ultrasound was only available for specific indications. The main outcome measures were number of antenatal visits and referrals for fetal surveillance. RESULTS: The two cohorts were comparable except for the number of primigravidas but stratified analysis according to parity did not affect the results. Ultrasonography did not alter pregnancy outcome but reduced the number of perceived preterm labors/ruptured membranes (12.0 vs. 16.7%, P<0.003), post-term deliveries (8.1 vs. 10.8%, P<0.04) and referrals for fetal surveillance [15.9 vs. 29.6%, P<0.000, RR 0.79 (0.71-0.88)]. CONCLUSIONS: This community-based basic ultrasound service significantly reduced referrals to a regional center for fetal surveillance and delivery.  相似文献   
58.
The purpose of this debate is to argue the merits of whether the availability of 24-hour transvaginal ultrasound service in every unit will help predict and, subsequently, prevent preterm birth. Any new test introduced will need to fulfil certain criteria. It must be acceptable in terms of risk, cost and patient convenience. It must be an improvement over existing alternatives, and it must aid clinicians to improve care. While the 24-hour availability of transvaginal ultrasound to every maternity unit may be useful to research and teaching, there is, as yet, little evidence that a 24-hour transvaginal ultrasound service improves perinatal and maternal morbidity and mortality. Results from our own centre suggest that experienced clinicians can make an acceptable diagnosis of spontaneous preterm labour (PTL) using only history and digital examination. Based on these findings, the availability of 24-hour vaginal ultrasound in every unit cannot be justified for the diagnosis of spontaneous PTL.  相似文献   
59.
The usefulness of the vascular ultrasound in the field of obstetrics is now well recognized. Intima-media thickness (IMT) and elastic property of the common carotid artery are affected by pregnancy and vary with complications. Flow-mediated vasodilation (FMD) of the brachial artery reflects the vascular endothelial function and is reported to be useful in the management of complicated pregnancy, especially pre-eclampsia. For the screening of deep vein thrombosis of the lower extremities in the perinatal period, compression ultrasonography (CUS) is useful.  相似文献   
60.
目的:利用彩色多普勒超声筛查孕中晚期胎儿异常或畸形,降低围产死亡率,提高人口出生质量。方法:对我院2002年1月至2005年3月1980例孕中晚期胎儿彩色多普勒超声检查结果回顾性分析。结果:检出胎儿畸形45例,死胎12例,低置胎盘24例,38周~42周胎位不正51例、脐绕颈316例。其中绝大多数在本院或外院引产证实,少数经过尸解证实。结论:彩色多普勒超声可发现大多数的胎儿形态结构异常,使一些致死性的畸形及早终止妊娠,非致死性的异常或畸形有了选择的空间;在提高人的出生质量上彩色多普勒超声起着不可或缺的作用,而且越来越显现出其独特的功能所在。  相似文献   
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