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1.
A combined one- and two-dimensional ultrasonic system for monitoring respiratory movements in the human fetus has been developed. A real-time cross-sectional image of the fetal chest at the level of the fetal heart can be obtained, and a time motion recording of fetal respiratory movements can then be written on a strip-chart recorder. Combining the features of one-dimensional and two-dimensional systems produces an accurate means of investigating fetal breathing movements.  相似文献   

2.
Analysis of autopsy data shows that, from the 26th through the 38th gestational weeks, fetal brain weight (BrW) is a function of the 3.124 power of the largest head circumference (HC). Because there is excellent correlation between prenatal ultrasound measurement and postnatal tape measurement of the HC, it is possible to determine fetal BrW in utero. An alteration of the BrW:somatic weight (SW) relationship is an important physical stigma of asymmetric intrauterine growth retardation (IUGR). The value of longitudinal studies of fetal BrW and SW as a means of discriminating between normal and asymmetric growth is tested in a population at risk for IUGR.  相似文献   

3.
Normal values of the pulsatility index in the fetal renal arteries in a group of 65 uncomplicated pregnancies were established. The measurements were obtained between 28 and 40 weeks of gestation. The values of pulsatility index may be used as a reference for further investigation of pathologic pregnancies.  相似文献   

4.
We present a case of intrapericardial teratoma diagnosed by ultrasound at 26 weeks of gestation presenting as a large tumour mass and rapid development of hydrops fetalis. The fetus died in utero one day before scheduled open fetal surgery.  相似文献   

5.
BACKGROUND: Carotid angioplasty (CA) has been suggested to be a safer and more cost-effective alternative to carotid endarterectomy (CEA) in the management of symptomatic severe internal carotid artery (ICA) disease. METHODS: The study was conducted as a prospective consecutive randomized trial of CEA versus CA for symptomatic severe ICA disease in a university teaching hospital. All patients were assessed before and after surgery by a neurologist. The study consisted of 23 patients with focal carotid territory symptoms and severe ICA stenosis (> 70%) who were randomized to either CEA or CA. However, only 17 had received their allocated treatment before trial suspension. CEA with patching or CA with stenting were used as interventions. The main outcome measures were death or disabling or nondisabling stroke within 30 days. RESULTS: All 10 CEA operations proceeded without complication, but 5 of the 7 patients who underwent CA had a stroke (P=.0034), 3 of which were disabling at 30 days. CONCLUSIONS: After referral, the Data Monitoring Committee invoked the stopping rule and the trial was suspended. The investigators and the Ethics Committee subsequently concluded that the trial could not be restarted--even in an amended format-primarily because of problems with informed consent. We review many of the ethical dilemmas encountered in the performance of this study. If future trials do suggest a selected role for CA, it is essential that both the inclusion and the exclusion criteria are fully documented.  相似文献   

6.
Fractal methods have been found to be useful in characterizing biomedical signals. The use of fractal estimation requires the estimation of parameter H, which is directly related to the fractal dimension D. Here, we propose a new approach which is a combination of the wavelet transform and fractal estimators to characterize the human fetal breathing signals before and after the intake of two glasses of wine by a mother. This study was performed on 26 fetuses. The variances of the wavelet coefficients were estimated at each scale. The slope of the representation on a logarithmic plot from the scales 5 to 1 was found to be increased after alcohol intake. Our results suggested that fetal breathing rates have a rough structure before the alcohol intake and a smooth structure after alcohol intake.  相似文献   

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Changes in glycoprotein and ganglioside composition in human trophoblasts (eighth week of gestation) after in vitro exposure to pulsed Doppler ultrasound (pulse duration 1.22 microseconds; repetition frequency 11.1 kHz; center frequency 4 MHz; ISPPA = 175.5 W/cm2; ISPTA = 0.59 W/cm2) were investigated. Evacuated trophoblasts were divided in two halves and insonated for 10 min on top of a 6-cm layer of 5% gelatin in 50-mL tubes (Falcon) at 37 degrees C. One half of each trophoblast was sham insonated and served as an internal control. After insonation trophoblasts were maintained at 37 degrees C for 24 h. Glycoproteins were detected using alpha-D-mannose specific lectins from Galanthus nivalis and Narcissus pseudonarcissus. A decrease in the expression of mannose containing glycoprotein mgp47 and an increase in expression of mgp54 were observed. Ganglioside composition was also significantly altered. Concentrations of two gangliosides migrating similarly to GM2, and one similarly to GQ1, decreased by more than 75%. At the same time, concentrations of one ganglioside migrating similarly to GM3, and two other unidentified gangliosides increased two- to fourfold.  相似文献   

9.
We investigated 69 healthy women with normal pregnancy and delivery in order to establish normal values for the second trimester of gestation. In a cross-sectional study we measured the pulsatility index (PI), the maximal systolic velocity (V-MAX) and the mean velocity (V-MEAN) in the uterine arteries (UAA), the umbilical artery (UA), the fetal thoracic aorta (FTA) and the middle cerebral artery (MCA) from the 14th to the 24th week of gestation. A regression analysis shows a significant slope of the PI of UAA and UA (p < 0.01), whereas in contrast to the UA there is no significant difference of the median values of the UAA-PI from the 18th week of gestation. With progressive gestation V-MEAN of UAA increases more (p < 0.001) than V-MAX (p < 0.05) as a result of the increasing diastolic blood flow. In the UA there is also a significant rising trend of V-MAX and V-MEAN (p < 0.0001). No significant changes of the PI of FTA and MCA are seen, although there is a slight increasing trend. After the 20th week in the MCA a marked tendency to high PI-values is observed, whereas there is a change between different flowpatterns prior to the 20th week. V-MAX and V-MEAN of FTA increases significantly, but there is no change in the MCA. Our results for UAA and UA correspond to the known morphologic changes in the utero- and fetoplacental vessels in the second trimester and are comparable to other results. Particularly the physiology of the cerebral perfusion needs to be investigated more intensively. These normal values provide a good basis for early and complex assessment of a disturbed perfusion in the second trimester.  相似文献   

10.
Respiratory activity (diaphragmatic electromyogram) was recorded in six unanesthetized in utero fetal lambs, between 0.7 of gestation and term. Respiratory patterns generated by the fetus showed developmental changes that included 1) an emergence of a periodic modulation of respiratory rate producing alternating active and quite phases (mean cycle length of 37 min between 130 and 140 days' gestation; 2) an increase in percentage apnea (expiratory time greater than 10 s) from 20% at 110 days to 60% at 140 days; and 3) a linear decrease in the 2-h average respiratory rate, while mean rate during active phases showed no consistent gestational decline. Electrocortical and electroocular activity was monitored in three of six fetuses; however, discrete sleep state patterns could not be consistently identified. The results demonstrate a gestational change in the respiratory patterns of the developing fetus and suggest an orderly maturation of the mechanisms controlling respiratory neuronal output.  相似文献   

11.
Measurement of fetal tissue protein synthetic rate in the lamb in utero   总被引:1,自引:0,他引:1  
The fractional synthesis rate of the mixed proteins in the organs of fetal lambs at 123 to 130 days' gestation were calculated from measurements of the rate of uptake of L14Clysine by the protein in the steady state in utero. The fractional synthesis rates were 82, 121 and 99 per cent per day for the brain, liver and cardiac muscle respectively; the average values of 40 per cent for skeletal muscle was significantly smaller than for the other tissues. The fetal fractional protein synthetic rates measured were similar to those of the newborn lamb, but faster than in the adult sheep by a factor of 10. Similar differences in synthesis rates have been observed between the young and adult rat and the possible reasons for the change in fractional rate during growth are discussed.  相似文献   

12.
In B-mode ultrasound abdominal studies, vascular structures may be confused with other tissues. A pulsed Doppler unit was coupled to a B-mode scanner by attaching the Doppler transducer to the B-mode transducer. A standardization procedure was designed to assure that the ultrasound beams from the 2 transducers were properly aligned, and that the Doppler focusing was accurate. The Doppler signal may be obtained from any point in the B-mode image in order to differentiate vascular structure from other tissue types.  相似文献   

13.
OBJECTIVE: To search the novel gene related to human hepatoma. METHODS: Northern blot analysis was used to isolate from EST (expressed sequence tags) clones a cDNA fragment differentially expressed in hepatocellular carcinoma versus its surrounding noncancerous hepatic tissue. Human fetal liver cDNA library was screened with EST fragment probe. RESULTS: Northern blot analysis showed that EST clone F9391 expressed at high level in all the 6 hepatocellular carcinoma samples but low level in the surrounding noncancerous hepatic tissues and 2 normal liver tissues. In further screening of human fetal liver cDNA library, we obtained a positive clone named FL6. Nucleotide sequencing indicated that FL6 contained 1464 base pairs and the matched DNA sequence was not found in the gene data bases (EMBL 96.6). Northern blot analysis of various fetus tissues with FL6 probe showed a high level expression in lung, small intestine, skin and placenta, middle level expression in liver, stomach, colon and muscle but low level expression in brain, thyroid, thymus, heart, kidney, pancreas and bladder. CONCLUSION: The results suggested that FL6 gene related to cell proliferation and may play an important role in the process of oncogenesis.  相似文献   

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16.
Fibroblast accumulation in a cutaneous wound requires phenotypic modulation of fibroblasts. In response to injury, resident fibroblasts in the surrounding tissue proliferate for the first 3 days and then at day 4 migrate into the wounded site. Once within the wound, they produce type I procollagen as well as other matrix molecules and deposit these extracellular matrix molecules in the local milieu. By day 7, abundant extracellular matrix has accumulated and fibroblasts switch to a myofibroblast phenotype replete with actin bundles along the cytoplasmic face of the plasma membrane. Wound contraction occurs as these myofibroblast gather in the wound extracellular matrix by extending pseudopodia, attaching to extracellular matrix molecules, such as fibronectin and collagen, then retracting the pseudopodia. Once these processes have been accomplished, the fibroblasts appear to undergo apoptosis. Therefore, during cutaneous wound repair, fibroblasts appear to progress through four phenotypes: first proliferating, second migrating, third synthesizing extracellular matrix molecules, and fourth expressing thick actin bundles as myofibroblasts.  相似文献   

17.
One of the principal disadvantages of the passive pill as a telemetric method for measuring various physiological parameters has been its resticted range. The reasons for the restricted range with existing detection methods are discussed. An improved method using a locking spectrometer based on third-order phase-sensitive detection is described and its performance is assessed. A significant increase in the usable range of a high sensitivity passive pill is obtained.  相似文献   

18.
Previous studies have revealed a placental extract that inhibits breathing in fetal sheep. In the present study of 29 chronically instrumented sheep at 132+/-1 days of gestation, infusion of the 1-10 kDa extract inhibited breathing in 76% of the experiments whereas Krebs' solution inhibited it in 24%. It retained this activity after 6 months of freezing, after lyophilization, and upon lowering the pH during purification from 8.0 to 4.0, but it inhibited breathing in only 35% when the pH was lowered to 2.0. A significant dose-dependent effect was observed from a 16-fold dilution to a 4-fold concentration. Treatment of the extract with proteinase K or boiling reduced the activity to 30% or 26% inhibition, respectively. The activity was not adsorbed to an ion-exchange column at pH 7.0 or 8.0, but it was at pH 9.0 and it eluted with increasing NaCl concentrations. On a polyacrylamide gel the activity was eluted at a K(av) of 0.66 (82% inhibition), corresponding to between 2.5 and 4.5 kDa. These findings suggest that a peptide produced by the placenta, with a molecular mass between 2.5 and 4.5 kDa, inhibits fetal breathing.  相似文献   

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20.
Fetal alcohol syndrome is one of the leading causes of birth defects in this country. Children exposed to alcohol in utero suffer from growth and mental retardation, physical abnormalities, and immune dysfunction. Previous work from this laboratory demonstrated that B lymphopoiesis is delayed in mice exposed to alcohol in utero. The deficit in B-cell development was apparent shortly after birth and extended to well after weaning. Because lymphopoiesis begins in the fetal liver, the current study was done to determine if fetal B-cell development was affected as well by in utero exposure to alcohol. We now show that the effects of in utero alcohol exposure on B lymphopoiesis do not become apparent until late in gestation. Flow cytometry was used to enumerate several intermediates in the B-cell developmental pathway. These phenotypic analyses showed that before day 17 of gestation, B-lineage intermediates developed normally when compared with control animals. However, between days 17 and 18 of gestation, an abnormality in the population dynamics of B-lineage intermediates became apparent in the fetal liver of alcohol-exposed mice. Early intermediates in the B-cell developmental pathway were present in normal numbers; however, the more mature progenitors as well as B cells were decreased in number by gestational day 18. These data suggest that in utero alcohol exposure disrupts the ability of B-lineage intermediates to progress along the developmental pathway to maturity, thereby leaving the animal immunocompromised at birth.  相似文献   

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