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131.
J W Goldkrand S U Lentz A D Turner S Clements H Sefter J Bryant 《The Journal of reproductive medicine》1999,44(4):346-350
OBJECTIVE: To study Doppler velocimetry in fetuses with a single umbilical artery (SUA) as compared to normal. STUDY DESIGN: Private and clinic patients were referred to a perinatal center: 45 with SUA and 124 randomly selected fetuses with a three-vessel cord were studied from 18 to 41 weeks' gestation. Color Doppler flow and energy were utilized to evaluate the umbilical arteries at the fetal abdominal wall as well as the course around the bladder. In addition to Doppler velocimetry, an anatomic survey, estimated fetal weight (EFW) and amniotic fluid index (AFI) were assessed at each examination. RESULTS: Doppler velocimetry in SUA demonstrated indices in the normal range but lower than in normal cords from 26 weeks until near term. Anatomic anomalies were found in 8.9% of SUA as compared to 4.8% for three-vessel cords. Intrauterine growth restriction (IUGR) was seen in four cases of SUA and none in the control group. EFW and AFI for both groups were virtually identical. CONCLUSION: SUA cords theoretically carry a normal blood volume, and the decreased resistance to flow and larger arterial diameter allow this to occur. Anomalies and IUGR are elevated in infants with SUA. Overall, EFW and AFI were the same in both groups of patients. 相似文献
132.
D D Solomon W L Arnold N D Martin D J Lentz 《Journal of biomedical materials research》1987,21(1):43-57
A new method has been developed to evaluate the relative thrombogenicity of vascular catheters. The technique provides a means to quantitatively differentiate between catheters made from different polymeric materials. Autologous In-111 labeled platelets were infused into a dog model and catheters were then inserted into the external jugular vein of the dog. The neck region was scanned using gamma camera imaging. Comparisons between catheter materials were made using computer generated uptake slopes during the first 40 min of the scan. In addition to scintigraphy, visual assessment of thrombus deposition, thrombus weight, platelet deposition, and scanning electron microscopy were used to validate the technique. Poly(vinyl chloride), polyurethane, heparinized polyurethane, and silicone catheter materials were tested. It was found that heparinized polyurethane was the least thrombogenic of all materials evaluated. 相似文献
133.
134.
Partial nodular transformation of liver in an adult with persistent ductus venosus. Review with hypothesis on pathogenesis 总被引:4,自引:0,他引:4
Partial nodular transformation of the liver (PNT) is a rare condition of unknown pathogenesis in which nodules composed of hepatocytes replace portions of the parenchyma. There is usually evidence of portal hypertension and portal vein thrombosis. We present a case of PNT in a man with persistent ductus venosus and hypoplasia of the major intrahepatic portal veins but without evidence of portal hypertension or portal vein thrombosis. Portal venules were largely absent between nodules, as documented by morphometry. We suggest the pathogenesis of PNT is similar to that previously proposed for nodular regenerative hyperplasia, that is, atrophy occurs in parenchyma with insufficient blood supply and nodules arise by hyperplasia in areas with adequate supply. Partial nodular transformation and nodular regenerative hyperplasia differ mainly in the cause and distribution of the portal vein obliteration. 相似文献
135.
136.
Boris Guiu Patrick Chevallier Alban Denys Elisabeth Delhom Marie-Ange Pierredon-Foulongne Philippe Rouanet Jean-Michel Fabre François Quenet Astrid Herrero Fabrizio Panaro Guillaume Baudin Jeanne Ramos 《European radiology》2016,26(12):4259-4267
Purpose
To assess technical feasibility, safety, and efficacy of the liver venous deprivation (LVD) technique that combines both portal and hepatic vein embolization during the same procedure for liver preparation before major hepatectomy.Materials and methods
Seven patients (mean age:63.6y[42-77y]) underwent trans-hepatic LVD for liver metastases (n?=?2), hepatocellular carcinoma (n?=?1), intrahepatic cholangiocarcinoma (n?=?3) and Klatskin tumour (n?=?1). Assessment of future remnant liver (FRL) volume, liver enzymes and histology was performed.Results
Technical success was 100 %. No complication occurred before surgery. Resection was performed in 6/7 patients. CT-scan revealed hepatic congestion in the venous-deprived area (6/7 patients). A mean of 3 days (range: 1–8 days) after LVD, transaminases increased (AST: from 42?±?24U/L to 103?±?118U/L, ALT: from 45?±?25U/L to 163?±?205U/L). Twenty-three days (range: 13–30 days) after LVD, FRL increased from 28.2 % (range: 22.4–33.3 %) to 40.9 % (range: 33.6–59.3 %). During the first 7 days, venous-deprived liver volume increased (+13.4 %) probably reflecting vascular congestion, whereas it strongly decreased (-21.3 %) at 3-4 weeks. Histology (embolized lobe) revealed sinusoidal dilatation, hepatocyte necrosis and important atrophy in all patients.Conclusion
Trans-hepatic LVD technique is feasible, well tolerated and provides fast and important hypertrophy of the FRL. This new technique needs to be further evaluated and compared to portal vein embolization.Key Points
? Twenty-three days after LVD, FRL increased from 28.2 % (range:22.4-33.3 %) to 40.9 % (range:33.6–59.3 %) ? During the first 7 days, venous-deprived liver volume increased (+13.4 %) ? Venous-deprived liver volume strongly decreased (mean atrophy:229 cc; -21.3 %) at 3-4 weeks ? Histology of venous-deprived liver revealed sinusoidal dilatation, hepatocyte necrosis and important atrophy137.
Joan L. F. Shaver Martha Lentz Carol A. Landis Margaret M. Heitkemper Dedra S. Buchwald Nancy F. Woods 《Research in nursing & health》1997,20(3):247-257
The purpose of this investigation was to compare self-reported sleep quality and psychological distress, as well as somnographic sleep and physiological stress arousal, in women recruited from the community with self-reported medically diagnosed fibromyalgia (FM) to women without somatic symptoms. Eleven midlife women with FM, when compared to 11 asymptomatic women, reported poorer sleep quality and higher SCL-90 psychological distress scores. Women with FM also had more early night transitional sleep (stage 1) (p < 0.01), more sleep stage changes (p < 0.03) and a higher sleep fragmentation index (p < 0.03), but did not differ in α-EEG-NREM activity (a marker believed to accompany FM). No physiological stress arousal differences were evident. Less stable sleep in the early night supports a postulate that nighttime hormone (e.g., growth hormone) disturbance is an eitiologic factor but, contrary to several literature assertions, α-EEG-NREM activity sleep does not appear to be a specific marker of FM. Further study of mechanisms is needed to guide treatment options. © 1997 John Wiley & Sons, Inc. Res Nurs Health 20: 247–257, 1997 相似文献
138.
Brett A. Faine Sanjana Dayal Rahul Kumar Steven R. Lentz Enrique C. Leira 《Journal of stroke and cerebrovascular diseases》2018,27(10):2720-2724
Introduction
Rural and critical access hospitals rely on the “drip and ship” practice using helicopter emergency medical services (HEMS). But those helicopter flights are an unusual environment with physical factors such as vibration and accelerations that could potentially affect the stability, and pharmacological properties of IV rtPA, an issue that has not been previously addressed.Materials and Methods
This was a prospective cohort study of consecutive acute ischemic stroke patients receiving IV rtPA through a Comprehensive Stroke Center from November 2015 to February 2017 to measure the effects of HEMS on the integrity and activity of rtPA by collecting residual medication left in the vial.Clinical Trial Registration
http://www.clinicaltrials.gov. NCT02752256Results
A total of 33 patients and rtPA samples were included; 18 patients who presented directly to the Comprehensive Stroke Center emergency department and 15 patients who received rtPA during air ambulance transfer. The median rtPA antigen concentration in the residual medication vial was 3.04 mg/mL (IQR: 1.24-3.87) in the HEMS group and 1.91 mg/mL (IQR: 1.33-2.60) in the controls (P = .168). There were no significant differences in rtPA activity or specific activity between the HEMS and control groups and there was no association between total HEMS flight time on overall rtPA specific activity.Conclusions
In summary, this study provides supportive evidence of the lack of a detrimental effect of the HEMS physical environment on the integrity of rtPA, therefore endorsing current drip and ship practices without infusion adjustments. 相似文献139.
140.