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1.
In contrast to the reduction in perinatal mortality in high-risk pregnancies, screening of low-risk pregnancies with umbilical artery Doppler ultrasonography has shown no benefit. Advances in pathophysiology question the assumption that the placenta is hypoxic in fetal growth restriction, with absent end-diastolic frequencies in the umbilical artery. The timing of delivery in relation to Doppler findings is uncertain, and so trials that relate Doppler findings to neurodevelopmental outcome are necessary to refine the role of this technique in obstetric practice.  相似文献   

2.
Two children aged 9 and 11 years suffered from left elbow sprain and right anterior tibial tuberosity cortical fracture respectively and were treated with plaster cast immobilization for about 30 days. They regained normal strength afterwards, but 9 and 2 months later developed insidious progressive weakness and wasting in the affected limb, mainly evident in the musculature surrounding the site of injury and sparing hand and foot muscles. Two to three years later the condition stabilized. Sensory abnormalities were not found. Electromyographic examination showed neurogenic pattern confined to the impaired extremity. The focal quality and the unusual disposition of muscle involvement suggest a correlation between trauma and/or immobilization and monomelic amyotrophy.  相似文献   

3.
To evaluate a random single Doppler study of the systolic to diastolic ratio of the umbilical artery as a predictor of perinatal outcome in diabetic pregnancies, a prospective double-blind study was performed in 92 diabetic pregnant women between 28 and 40 weeks of gestation. Main outcome measures were perinatal outcome: group A, normal outcome; group B, poor outcome. The sensitivity and specificity of the Doppler studies as a predictor of poor perinatal outcome were 39% and 92%, respectively. The positive and negative predictive values were 54% and 86%, respectively. Our results suggest that the systolic to diastolic ratio of the umbilical artery offers no advantage over other well-established tests in the management of diabetic pregnancies.  相似文献   

4.
BACKGROUND: Traumatic tattoos result from mechanical penetration of the skin by foreign-body particles associated with puncture, abrasive, or explosive trauma. Until the recent development of the Q-switched lasers, it was not possible to remove tattoo pigments without scar and pigmentary changes. OBJECTIVE: The objective of this study was to determine the effectiveness of the Q-switched alexandrite laser (wavelength, 755 nm; pulsewidth, 100 ns), in treating the 27 cases of Asian skin with 36 traumatic tattoos and to observe any side effects such as scarring or pigmentary change. METHODS: The results of treatments on 16 patients with 19 penetrant tattoos, 10 patients with 16 abrasive tattoos and 1 patient with bomb explosion were clinically analyzed. RESULTS: Greater than 76% removal of tattooed pigments required an average of 1.7 treatment sessions in penetrant tattoos in contrast with 2.4 sessions in abrasive tattoos. The excellent removal of traumatic tattoos required 7.5 J/cm2 except the scarred region of one explosive tattoo and one abrasive tattoo on soil. There were no permanent side effects such as scar or permanent pigmentary changes. CONCLUSION: In conclusion, the Q-switched alexandrite laser is a safe and highly effective modality for removal of various traumatic tattoos without scar or permanent pigmentary change in Asian skin.  相似文献   

5.
OBJECTIVE: Because twins are a high-risk group for preterm birth, many clinicians routinely use prophylactic interventions such as home bed rest, hospital bed rest, oral tocolytics, or home uterine activity monitoring to prevent preterm delivery. We sought to identify twin gestations at low risk for spontaneous preterm birth with transvaginal ultrasonography of the cervix to avoid the unnecessary use of prophylactic interventions in these pregnancies. STUDY DESIGN: We measured cervical length at 24 to 26 weeks' gestation by transvaginal ultrasonography in women with twin gestations referred to our prematurity prevention clinic. Each delivery was classified as (1) spontaneous preterm birth < 34 weeks' gestation, (2) delivery at > or = 34 weeks' gestation with intervention, or (3) delivery at > or = 34 weeks' gestation without intervention. Intervention included strict bed rest at home or in the hospital, either parenteral or oral tocolysis, or both, or home uterine activity monitoring. Indicated preterm deliveries and patients with cerclage were excluded from this analysis. The ability of transvaginal cervical length to predict women who would deliver at > or = 34 weeks without intervention was evaluated. A cervical length of 35 mm was chosen by scatter diagram as the best cutoff to discriminate between the group delivered at term without intervention and the other two groups. RESULTS: Of 85 women with twin gestations who underwent ultrasonographic cervical length measurements at 24 to 26 weeks' gestation, 17 had spontaneous preterm birth at < 34 weeks, 23 were delivered at > or = 34 weeks but required intervention, and 45 were delivered at > or = 34 weeks without intervention. The mean cervical length for those delivered at > or = 34 weeks' gestation without intervention (36.4 +/- 5.8 mm) was significantly greater (p < 0.0001) than the mean for those delivered preterm (27.4 +/- 8.5) and those delivered at > or = 34 weeks' gestation who required intervention (27.7 +/- 10.5 mm). The sensitivity, specificity, and positive and negative predictive values of a cervical length > 35 mm for predicting delivery at > or = 34 weeks' gestation are 49%, 94%, 97%, and 31%, respectively. CONCLUSION: A transvaginal ultrasonographic measurement of the cervix of > 35 mm at 24 to 26 weeks in twin gestations can identify patients who are at low risk for delivery before 34 weeks' gestation.  相似文献   

6.
7.
BACKGROUND: With improved survival of preterm infants, questions have been raised about the limit of viability. To provide better information and counseling for parents of infants about to be delivered after 22 to 25 weeks' gestation, we evaluated the mortality and neonatal morbidity of preterm infants born at these gestational ages. METHODS: We studied retrospectively all 142 infants born at 22 to 25 weeks' gestation (as judged by best obstetrical estimate) from May 1988 through September 1991 in a single hospital. Mortality in the first six months, including stillbirths, and neonatal morbidity (i.e., the presence of intracranial pathologic conditions, chronic lung disease, and retinopathy of prematurity) were analyzed. RESULTS: Fifty-six infants (39 percent) survived for six months. Survival improved with increasing gestational age; none of 29 infants born at 22 weeks' gestation survived, as compared with 6 of 40 (15 percent) born at 23 weeks, 19 of 34 (56 percent) born at 24 weeks, and 31 of 39 (79 percent) born at 25 weeks. There were seven stillbirths at 22 weeks' gestation and four stillbirths at 23 weeks. The more immature the infant, the higher the incidence of neonatal complications as determined by the number of days of mechanical ventilation, the length of the hospital stay, and the presence of retinopathy of prematurity, periventricular or intraventricular hemorrhage, or periventricular leukomalacia. Only 2 percent of infants born at 23 weeks' gestation survived without severe abnormalities on cranial ultrasonography, as compared with 21 percent of those born at 24 weeks and 69 percent of those born at 25 weeks. CONCLUSIONS: We believe that aggressive resuscitation of infants born at 25 weeks' gestation is indicated, but not of those born at 22 weeks. Whether the occasional child who is born at 23 or 24 weeks' gestation and does well justifies the considerable mortality and morbidity of the majority is a question that should be discussed by parents, health care providers, and society.  相似文献   

8.
OBJECTIVE: To determine if antenatal vitamin K and phenobarbital therapy affect coagulation studies in umbilical blood at birth, and to provide 95% reference ranges for umbilical blood coagulation parameters in premature gestations. METHODS: Patients at imminent risk for spontaneous or indicated premature delivery less than 34 weeks' gestation were randomized to receive either placebo or vitamin K and phenobarbital. Prothrombin time (PT), activated partial thromboplastin time (PTT), functional coagulation factors, and decarboxylated prothrombin assays were performed on umbilical blood specimens. Decarboxylated prothrombin, also known as "protein induced by vitamin K absence-factor II" or precursor prothrombin, is a sensitive marker for vitamin K deficiency. Standardized values of PT and PTT are reported in seconds and standardized values of factor assays in percentage of normal adult functional activity (mean +/- one standard deviation). RESULTS: Newborns in the placebo and treatment groups had similar umbilical blood PT (12.6 +/- 1.2 versus 12.7 +/- 1.4 seconds), PTT (48.8 +/- 13.4 versus 49.6 +/- 13.8 seconds), and functional activity of factor II (40.3 +/- 12.5 versus 42.0 +/- 12.1%), factor VII (67.0 +/- 20.9 versus 66.8 +/- 18.9%), factor IX (27.4 +/- 12.8 versus 25.8 +/- 8.9%), and factor X (47.0 +/- 12.8 versus 49.2 +/- 11.6%). Newborns in the treatment group were about half as likely as those in the placebo group to have detectable decarboxylated prothrombin levels in umbilical blood at birth (gestational age-adjusted odds ratio 0.47, 95% confidence interval 0.22-1.01; P = .05). CONCLUSIONS: Combined maternal therapy with vitamin K and phenobarbital before premature delivery does not affect umbilical blood PT, PTT, or functional activity of vitamin K-dependent coagulation factors II, VII, IX, and X. However, it is associated with the reduced presence of decarboxylated prothrombin in umbilical blood at birth. There is significant improvement in umbilical blood coagulation tests as gestational age advances from 24 to 34 weeks.  相似文献   

9.
OBJECTIVES: To study the incidence of chronic oxygen dependency (COD) among ventilated survivors born at 24-32 weeks gestation from 1986 to 1994 and to identify antenatal and neonatal factors that may have changed with time; and to identify antenatal and neonatal factors that could contribute to the development of COD in infants born at 24-32 weeks gestation using a case control model. METHODOLOGY: Infants born at 24-32 weeks gestation in one tertiary referral centre between 1986 and 1994 and admitted to the neonatal intensive care unit for respiratory support were studied. Data accumulated prospectively since 1986 in survivors of ventilation were analyzed to identify antenatal and neonatal factors that could have changed with time. The cohort of infants who developed COD were matched for gestation and time of birth with a control group of infants who did not have COD. Significant factors that could have contributed to the development of COD were identified using forward logistic regression analysis. RESULTS: The number of mothers admitted for threatened premature labour (TPL), and pregnancy induced hypertension decreased with time while the use of antenatal steroids and maternal antibiotics increased. More infants were delivered by Caesarean section during the later years. There was an increase in neonatal septicaemia with time while there were decreases in hyaline membrane disease, pneumothorax, pulmonary interstitial emphysema, use of high peak inspiratory pressure (PIP) and high inspired oxygen. The incidence of COD decreased. The case controlled study revealed a significant positive association between COD and male gender, birthweight less than the 10th percentile for gestation, PIP over 30 cm H2O, septicaemia and significant patent ductus arteriosus (PDA) requiring indomethacin. There was a negative association with TPL. CONCLUSIONS: Further decrease in COD can be achieved only if septicaemia, PDA and the use of high PIP can be avoided. The most effective way of reducing the incidence of COD is by reducing the incidence of prematurity.  相似文献   

10.
OBJECTIVE: To determine the changes in the vessel-wall thickness and the radius of the lumen in tertiary-stem villi of the placenta with advancing gestational duration and their relationship to umbilical artery Doppler flow studies. METHODS: Placentas from 63 miscarriages and preterm and term deliveries (between 19 and 40 weeks) were used for morphometric study of the tertiary-stem villi vessels. Each woman had undergone Doppler flow study of the umbilical artery. The resistance index (RI) was determined from the Doppler flow velocity waveform. Placental paraffin sections of 4-micron thickness were stained with hematoxylin and eosin and with periodic acid-Schiff reagents. The tertiary-stem villi and their vessels were examined microscopically and assessed morphometrically using a personal computer with math co-processor and a touch-sensitive screen overlying a video monitor. The monitor received microscopic images from a video camera that was mounted on a microscope. We determined vessel-wall thickness by tracing the outer and inner circumferences of digitized vessel-wall images. RESULTS: Wall thickness, but not lumen size, of the tertiary-stem villi vessels decreased significantly overall at a rate of 0.63micron/week (P < .001). The rate of decrease was 0.64micron/week (P < .001) during the second trimester and 0.50micron/week (P < .001) during the third trimester. There was a significant correlation between the decrease in thickness and in RI (r = 0.83 [P < .001], r = 0.78 [P < .001] in the second and third trimesters, respectively). Resistance indices were all within normal limits. CONCLUSIONS: Placental tertiary-stem villi vessel-wall thickness decreases with advancing gestational age. There is a correlation between the changes in RI of the umbilical artery Doppler flow and the changes in mean wall thickness of the placental vessels.  相似文献   

11.
OBJECTIVE: To compare the impact on use of resources in the management of small for gestational age babies using Doppler ultrasound versus cardiotocography. DESIGN: A randomised controlled trial. SETTING: A large district general hospital delivering 5500 to 6000 infants each year, 30% to 35% of which are to women of Pakistani origin. POPULATION: One hundred and fifty women delivered of small for gestational age infants. MAIN OUTCOME MEASURES: Primary outcome measures were length of hospital inpatient stay and induction of labour rates. Secondary outcome measures included caesarean section rates and length of stay on neonatal unit. RESULTS: The use of Doppler reduced average hospital inpatient stay from 2.5 days to 1.1 days, compared with cardiotocography (P = 0.036). There was no effect on induction of labour rates or caesarean section rates. There was no significant difference in length of stay on the neonatal unit (P = 0.33). There was a reduction in monitoring frequency and fewer hospital antenatal clinic visits. CONCLUSION: The use of Doppler ultrasound to manage small for gestational age infants reduces the use of resources, compared with cardiotocography.  相似文献   

12.
The topoisomerase II alpha (topo II alpha) enzyme is the target for several chemotherapeutic agents, including etoposide, teniposide, mitoxantrone, and doxorubicin (topo II poisons). The enzyme also is a marker of cell proliferation. Most cases of Hodgkin's disease (HD) are responsive to combination chemotherapy regimes that include topo II poisons such as doxorubicin. Immunoperoxidase methods for detection of the topo II alpha isoenzyme are now available for use in formalin-fixed, paraffin-embedded tissues, which may provide information about the proliferative capacity and possible sensitivity of tumors to drugs that target topo II. We used a specific antibody to analyze subsets of HD for topo II alpha staining patterns. Formalin-fixed blocks from 49 cases of HD, including 20 nodular sclerosis (NS), 14 mixed-cellularity (MC), and 15 lymphocyte-predominant (LP) subtypes, were analyzed by dual staining for topo II in combination with monoclonal antibodies against Reed-Sternberg (RS) cells consisting of CD15 for the NS and MC subtypes and CD20 for LP lymphocytic and histiocytic (L & H) cells. The number of morphologically appropriate cells coexpressing the RS or L & H marker and topo II alpha was quantitated. Positive nuclear staining for topo II alpha in RS or L & H cells was seen in 100% of cases, irrespective of subtype. Coexpression of CD15 and topo II alpha was seen in 58.4% of the RS cells or mononuclear variants in NSHD cases and 68.4% in MCHD cases. No significant difference in the percentage of neoplastic cells expressing topo II alpha was found between NS and MC subtypes. Cases of LPHD showed coexpression of CD20 and topo II alpha in 84.4% of the L & H cells, a significant increase over the level of tumor cell coexpression seen in NSHD and MCHD (P < .001). Only one case was found to have a low (< 25% of tumor cell coexpression) level of topo II alpha expression. Immunohistochemical detection of a high level of topo II alpha expression in HD, irrespective of subtype, suggests a molecular explanation for the excellent response of most HD to standard combination chemotherapy, which can include topo II poisons. The LP subtype has a higher expression of topo II alpha in the neoplastic cell population than do NS or MC subtypes, perhaps indicating increased sensitivity of these tumors to topo II poisons. It may be possible to identify subsets of HD that are more or less sensitive to conventional chemotherapeutic regimes, which would help in the selection of appropriate treatment.  相似文献   

13.
In singleton pregnancies at 10 to 14 weeks of gestation the prevalence of missed abortion is about 2%. In an ultrasound screening study at 10 to 14 weeks of gestation involving 492 twin pregnancies the prevalence of missed abortion was about twice as high as in singletons. The risk of subsequent miscarriage in twin pregnancies with one missed abortion was about ten times higher than in normal twin pregnancies. These findings may have important implications both in terms of counselling and for future research into the causes of miscarriage.  相似文献   

14.
As the availability of electron-beam CT increases, it is appropriate to question the balance among medical science, patient care, and profits. Broadening patients' sense of empowerment and promoting their autonomy are worthy goals within medicine. Breast-cancer screening with mammography is an example of a radiographic test used successfully in a diagnostic program based on self-referral. But the lessons of such a program, in which the distinction between the disease and the disease-free state is more easily recognized than is the case for age-dependent calcific arterial changes, are not easily extrapolated to screening for coronary disease. Currently, we are facing the possibility that market forces may increase interest in electron-beam CT beyond what is justified by its potential medical benefit. Well-designed clinical trials are required to define fully the appropriate indications for and limitations of electron-beam CT. Such trials will eventually clarify the medical applications of the technique and determine its suitability as a screening procedure for cardiovascular disease. Until then, the use of electron-beam CT, like that of all tests in medicine, should be based on a clearly defined rationale and should be coupled with a medical evaluation by a physician.  相似文献   

15.
A transoral noninvasive procedure in the oropharynx using local anesthesia was applied to detect flow in the vertebral arteries with a bidirectional continuous-wave Doppler ultrasound system. Common carotid artery compression was used to identify the vertebral artery. Flow direction, amplitude of flow signals, diastolic flow, and reaction of flow on common carotid artery compression served as diagnostic parameters. The procedure was applied in 90 patients of whom 42 underwent angiography. The method has proved to be 82% accurate. It was most reliable in the diagnosis of occlusion or aplasia, subclavian steal and normalcy, and was less reliable in the detection of stenosis or hypoplasia of a vertebral artery. Eleven patients with subclavin steal, five patients with a missing vertebral artery three patients with hypoplasia or stenosis, and 15 patients with normal angiorgraphical findings were correctly diagnosed by Doppler; normal Doppler findings were present in three patients with a mission or stenosed vertebral artery. Those patients (five) with Doppler indications of subclavian steal (one patient), missing vertebral artery (two patients), or stenosis (two patients) had normal angiograms. Application of the Doppler procedure, after 11 subclavin endarterectomies, informed the surgeon immediately about the hemodynamic effect of surgical intervention. Rethrombosis was diagnosed in two patients by postoperative Doppler examination.  相似文献   

16.
To detect stenosis in the carotid artery with a bidirectional continuous-wave Doppler ultrasound device, the following noninvasive procedure, applied on 800 patients and compared with 249 angiograms of 186 patients, has proved to be about 90% reliable. Measurements of flow signals were taken over the terminal branches of the ophthalmic artery (supratrochlear and supraorbital arteries) and averaged. Compression of superficial temporal and facial arteries revealed flow direction and common carotid artery compression revealed the supplying blood vessel and the effectiveness of the circle of Willis. Measurements over the common carotid arteries were used to evaluate peripheral resistance. A set of eight criteria was used; the diagnostic value of each criterion was calculated by comparing 138 pathological Doppler findings in 123 patients with the angiograms. If reverse flow direction in supratrochlear or supraorbital artery was used alone, only 43% correct diagnoses would have resulted. A more severe stenosis is not necessarily correlated with a more weighted criterion; a subset of criteria is less efficient than the combination of all criteria. Application during 32 extracranial endarterectomies on 28 patients informed the surgeon immediately about the hemodynamic effect of the surgical intervention. Rethrombosis was diagnosed in two patients by postoperative Doppler examination.  相似文献   

17.
BACKGROUND: To assess the relationship between placental inflammation, umbilical artery Doppler waveforms and fetal biophysical profile score, umbilical artery Doppler studies and fetal biophysical evaluations were performed in 24 preterm pregnants with premature rupture of membranes (PPROM). SUBJECTS: After delivery, the placentas were microscopically examined and two subgroups were formed including noninflamed or inflamed placentas. RESULTS: In the first group, which includes 14 cases with no histological signs of placental inflammation, we found increased systolic/diastolic ratio only in one patient, whereas in the second group including ten cases with microscopically proven inflammation, nine were found to have increased systolic/diastolic ratios (p < 0.05). Mean systolic/diastolic ratio in the first and the second groups were 2.74 +/- 0.18 and 4.64 +/- 0.93 respectively (p < 0.001). Mean biophysical profile score was 9 +/- 1.04 in the first group and 7 +/- 1.05 in the second group (p < 0.001). CONCLUSION: Abnormal biophysical profile scores along with increased arterial systolic/diastolic ratios have been shown to be the markers of impending clinical infection.  相似文献   

18.
19.
The authors present the results of a study carried out within the context of a diagnosis of the state of dental health among 300 twelve years old students in school in the province of Kadiogo (Burkina Faso). The data collected by questionnaires explore the range of behaviours linked to dental health: dental hygiene, eating habits, use of fluoride and use of dental health services. Half of students report that they brush their teeth at least once a day. Among them, there are 2 girls out of three, and one boy out of two. For half of the children, their mothers are the main people who teach them how to brush their teeth. For three children out of four, a tooth brush and tooth paste are the most common methods. Roughly 17% understand the usefulness of fluoride and 70% have never heard of it. Four children out of five consume sugared drinks on a daily basis. 85% say they have never been to the dentist. The information collected could serve as a base for the development and implementation of health promotion and education programmes for dental health within schools.  相似文献   

20.
OBJECTIVES: To examine the utility of measuring fetal nuchal translucency thickness in screening for major defects of the heart and great arteries at 10-14 weeks of gestation. DESIGN: Population based cohort study. SUBJECTS: 29 154 singleton pregnancies with chromosomally normal fetuses at 10-14 weeks of gestation. SETTING: Fetal medicine centre in London. MAIN OUTCOME MEASURE: Prevalence of major defects of the heart and great arteries. RESULTS: Of 50 cases with major defects of the heart and great arteries (prevalence 1.7 per 1000 pregnancies) 28 (56%, 95% confidence interval 42% to 70%) were in the subgroup of 1822 pregnancies with fetal nuchal translucency thicknesses above the 95th centile of the normal range. The positive and negative predictive values for this cut off point of nuchal translucency thickness were 1.5% and 99.9% respectively. CONCLUSIONS: Measurement of fetal nuchal translucency thickness-traditionally used to identify fetuses at high risk of aneuploidy-at 10-14 weeks of gestation can identify a large proportion of fetuses with major defects of the heart and great arteries.  相似文献   

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