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1.
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   

2.
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   

3.
The differentiation of pseudo-occlusion from complete internal carotid artery occlusion may have important clinical consequences for patients with the former tend not to benefit from reconstructive surgery. The Authors report a case in which color-Doppler duplex-scanner revealed a persisting string-like lumen that was not demonstrated by angiography. The Authors believe that ultrasonography may in future permit the reliable differentiation of pseudo-from complete carotid occlusion, thereby reducing the need for angiography.  相似文献   

4.
BACKGROUND: The clinical significance of plasma concentration of matrix metalloproteinase 9 (MMP-9) was investigated in patients with gastric cancer. METHODS: Plasma was obtained from 138 healthy individuals and 70 patients who underwent gastrectomy for gastric cancer at Aichi Cancer Centre between August 1994 and July 1995. Plasma concentrations of MMP-9 were measured using a one-step sandwich enzyme immunoassay employing monoclonal antibodies. RESULTS: Patients with gastric cancer had plasma higher concentrations of MMP-9 than normal subjects. Postoperative concentrations of MMP-9 were lower than preoperative levels. In addition to patients with advanced cancer, those with early gastric cancer also exhibited higher mean values of and positivity rates for MMP-9 than healthy individuals. Preoperative plasma MMP-9 concentration correlated closely with Union Internacional Contra la Cancrum tumour node metastasis (pTNM) stage, severity of T, N and M classification, and tumour size. CONCLUSION: Plasma MMP-9 concentration can be used for detection of primary or recurrent gastric cancer, and for estimation of tumour extent.  相似文献   

5.
OBJECTIVE: To investigate the effect of normal pregnancy and hypertensive disorders of pregnancy on the maternal renal artery Doppler blood flow velocity indices. METHODS: The patient material consisted of 30 normal pregnant women, 29 women with pregnancy induced hypertension, 43 women with preeclampsia and 22 pregnant women with chronic hypertension. Blood flow velocities in the segmental renal arteries from the right kidney were analysed by pulsed and color Doppler. The systolic/diastolic (s.d.) ratio, resistance index (RI) and pulsatility index (PI) were used for Doppler waveform analysis. RESULTS: In all of the groups of hypertensive pregnant women renal artery Doppler indices were significantly lower compared to the normal pregnant women group. There was a significant negative relationship between renal artery PI and mean arterial pressure in the preeclampsia group and in the chronic hypertension group. CONCLUSION: The present results demonstrate that the mechanism of renal autoregulation in preeclampsia might be altered, leaving glomerulus unprotected from increased blood pressure. It seems that the concept of renal vasoconstriction in preeclampsia might be disputed and needs further investigation.  相似文献   

6.
The aim of this study was to document the Doppler indices [pulsatility index (PI) and resistance index (RI)] of the uterine arteries in 30 patients who underwent hysteroscopic rollerball endometrial ablation for dysfunctional uterine bleeding by transvaginal pulsed Doppler sonography, and to reveal whether treatment failures (persistent menometrorrhagia) can be predicted by the blood flow characteristics of the uterine arteries in advance. On the basis of the outcome of patients at the end of the first postoperative year, the Doppler indices of the uterine arteries were meaningful 1 year after the operation when PI (1.32 +/- 0.11; mean +/- SD) and RI (0.71 +/- 0.04) in six menometrorrhagic patients were statistically different from PI (2.19 +/- 0.28; 1.95 +/- 0.36 and 1.82 +/- 0.37) and RI (0.87 +/- 0.06; 0.82 +/- 0.06 and 0.81 +/- 0.04) in normally menstruating, amenorrhoeic and hypomenorrhoeic patients respectively (P < 0.05). On the other hand, the patients who would be menometrorrhagic one year after the operation had a thicker endometrium in the first post-operative month. These findings suggest that the angiogenetic role of the persistent endometrial islands after endometrial ablation needs at some time to be reflected as changes in the Doppler parameters of the uterine arteries.  相似文献   

7.
Thirty cases of osteosarcoma of the jaws were reviewed (20 men and 10 women, mean age 34 years). Seventeen lesions occurred in the mandible and 13 in the maxilla. Swelling without pain was the most common presenting symptom. Thirteen lesions were initially misdiagnosed as odontogenic infections. Numbness as a presenting symptom was statistically associated with poor prognosis. Treatment included all combinations of surgery, chemotherapy and radiotherapy. Patients receiving chemotherapy with four or more agents showed a trend toward better survival with 71% alive and disease-free at the time of review. Patients' increasing age was statistically associated with decreased survival. The average age of survivors was 27 years and nonsurvivors, 40 years. Older patients suffered more local recurrences which, in all but one case, resulted in mortality. Expectedly, clear surgical margins correlated statistically with improved survival. With margins of less than 5 mm, 27% of patients were alive and disease-free as compared to 62% with surgical margins greater than 5 mm. The importance of early diagnosis, definitive surgical treatment and aggressive adjuvant chemotherapy is demonstrated. The Proportional Hazards Regression model was employed to evaluate the statistical significance of a variety of factors on disease-free and overall survival.  相似文献   

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PURPOSE: The purpose of this study was to assess the outcome after the shortening and reimplantation of tortuous internal carotid arteries to prevent kinking after endarterectomy. METHODS: Through a review of prospective records, we studied patients who underwent carotid endarterectomy (CEA) (n = 233) between 1993 and 1996 who had symptomatic stenosis of the internal carotid artery (ICA) of more than 70%. An elongated proximal ICA was excised, and the ICA was reimplanted into the bifurcation in 30 (13%) patients, with additional patch angioplasty in 5 patients. Of the remaining 203 patients, 50 (21%) had Dacron patch angioplasty, and the rest had conventional CEA with simple closure. RESULTS: In the reimplanted group, one patient had a minor stroke with complete recovery on discharge. Three patients (10%) had neck hematomas requiring reexploration, but in none of these was the bleeding from the artery. At mean follow-up of 15 months, 93% of the arteries were widely patent. Significant stenosis secondary to neointimal hyperplasia was detected in only two patients, for a restenosis rate of 6.7%, which is in line with other published reports. In the control group, 8 (3.9%) patients had perioperative transient ischemic attacks, 5 (2.5%) had strokes, and 13 (6.4%) had hematomas requiring evacuation. At follow-up, 14 (6.9%) of the arteries had restenosed. CONCLUSION: In carotid surgery, reconstructive techniques must be tailored to operative findings. Excision of a tortuous elongated proximal ICA with reimplantation is not associated with additional mortality or morbidity rates over those of conventional CEA alone and has the advantage of removing disease at the bifurcation. This procedure was carried out in 13% of our patients and should be a procedure with which the vascular surgeon is familiar.  相似文献   

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BACKGROUND AND PURPOSE: A subject with dissection of the internal carotid artery (ICA) may present with a variety of symptoms, from headache to stroke. Thus far, it has not been possible to identify the subset of patients at risk for cerebral ischemia. Because the majority of these ischemic events are secondary to embolic phenomena, we used transcranial Doppler (TCD) evaluation with emboli monitoring to study 17 consecutive patients with ICA dissection treated at Harborview Medical Center, Seattle, Wash, during a 2-year period from 1992 until 1994. METHODS: Ten patients with ICA dissection secondary to trauma and seven with spontaneous ICA dissection were diagnosed by carotid angiography and studied by TCD from the time of diagnosis through initiation of therapy. Emboli monitoring was performed in the middle cerebral artery (MCA) ipsilateral to the dissection at the initial evaluation and intermittently thereafter to ensure that the emboli stopped with treatment. RESULTS: Emboli were detected in the MCA distal to the dissection in 10 of 17 patients (59%). Patients with microemboli detected by TCD presented with a stroke (70%) much more frequently than those without emboli (14%) (P=.0498). The presence of a pseudoaneurysm did not increase the risk of either microemboli or stroke. CONCLUSIONS: We have demonstrated a high incidence of intracranial microemboli in the MCA distal to carotid dissections and a significant correlation between the presence of emboli and stroke. TCD can therefore be used as an adjunctive tool to manage patients with suspected carotid dissection and may prove useful in evaluating the efficacy of treatment in reducing microemboli and subsequent stroke.  相似文献   

12.
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   

13.
Actin-crosslinking proteins link F-actin into the bundles and networks that constitute the cytoskeleton. Dystrophin, beta-spectrin, alpha-actinin, ABP-120, ABP-280, and fimbrin share homologous actin-binding domains and comprise an actin crosslinker superfamily. We have identified a novel member of this superfamily (ACF7) using a degenerate primer-mediated PCR strategy that was optimized to resolve less-abundant superfamily sequences. The ACF7 gene is on human chromosome 1 and hybridizes to high molecular weight bands on northern blots. Sequence comparisons argue that ACF7 does not fit into one of the existing families, but represents a new class within the superfamily.  相似文献   

14.
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   

15.
Our objectives were to describe the flow velocity waveform of the fetal superior mesenteric artery and to establish a nomogram for its pulsatility index. In a cross-sectional study using color Doppler ultrasonography, superior mesenteric artery flow velocimetry was investigated prospectively in 96 healthy fetuses of between 14 and 37 weeks of gestation. In normal fetuses the pulsatility index measurements showed a slight but insignificant increase over the course of gestation (r = 0.26; P > 0.5). The lowest mean +/- standard deviation for pulsatility index in the superior mesenteric artery was 1.86 +/- 0.45 (95% confidence interval 1.67-2.06), recorded between 18 and 21 weeks' gestation. Thereafter the pulsatility index increased to 1.94 +/- 6.4 (95% confidence interval 1.74-2.8) at 22 to 25 weeks, and from weeks 26 to 29 it increased to 2.18 +/- 0.52 (95% confidence interval 1.91-2.46). During the third trimester and at term, the mean pulsatility index of 2.23 +/- 0.32 (95% confidence interval 1.43-3.03) did not change significantly with gestational age. In normal fetuses, except for the early stages, a relatively stable vascular resistance of the intestinal circulation was found. The application of this nomogram in clinical practice may facilitate evaluation of intestinal perfusion in compromised fetuses with blood flow centralization.  相似文献   

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18.
Two-dimensional ultrasonography was used in combination with colour-flow imaging and pulsed wave Doppler ultrasonography to study the maternal circulation and the development of fetal vascularization in six Beagles during normal gestation. For the first time, the development of the circulation was demonstrated in the bitch and her fetuses intra vitam. The bloodstream was examined in small uteroplacental arteries, the umbilical artery, the fetal aorta and the common carotid artery. The duration of the study was from week 3 after insemination until birth. Relatively large vessels were detected by cross-sectional ultrasonography, and small vessels were detected by colour-flow imaging. In pulsed wave Doppler ultrasonography, the blood flow was measured and described using the parameters of systolic peak velocity, diastolic peak velocity, end-diastolic velocity, pulsatility index, resistance index, A:B ratio (systolic peak velocity:end-diastolic velocity) and S:D parameter (systolic peak velocity:diastolic peak velocity). The development of the measured parameters is typical and similar to that in humans. The systolic peak velocity of the canine maternal uteroplacental arteries shows important differences in comparison with humans. The pulsatility index, resistance index and A:B ratio decrease in nearly all vessels. Only the fetal common carotid artery has constant pulsatility and resistance indices during gestation. For the first time, the quality and quantity of the normal blood flow have been monitored during the whole of gestation. A normal circulation is fundamental for supplying the fetus adequately with oxygen and nutrients and thus for physiological development. These ultrasonographic results are the basis for further clinical studies.  相似文献   

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BACKGROUND: A substantial proportion of patients undergoing heart catheterization for suspected coronary artery disease have normal angiograms. Coronary morphology and blood flow velocity can be assessed very accurately with intracoronary ultrasound and Doppler. The purpose of this study was to use both methods to classify further patients with suspected coronary artery disease but with coronary angiograms adjudged normal at the time. METHODS AND RESULTS: In forty-four patients with suspected coronary artery disease and normal coronary angiograms, intracoronary ultrasound and intracoronary Doppler were performed in the left anterior descending and left main coronary arteries. Coronary flow reserve was obtained by calculating the ratio of the maximal coronary flow mean velocity after the intracoronary administration of 10 mg papaverine to the coronary flow mean velocity at rest. Of 44 patients, 16 (36%) (group I) were found to have normal coronary morphology by intracoronary ultrasound and normal (> 3.0) coronary flow reserve (5.3 +/- 1.8). In seven patients (16%) (group II) there were normal intracoronary ultrasonic findings but a reduced coronary flow reserve (2.1 +/- 0.4). Plaque formation was found in a total of 21 (48%) of the 44 patients; mean plaque sizes were 3.6 +/- 1.6 mm2 for those in group III (normal coronary flow reserve) and 5.0 +/- 2.3 mm2 for those in group IV (reduced coronary flow reserve). Vessel area in both of these groups (16.3 +/- 8.0 mm2 and 19.2 +/- 6.1 mm2) was significantly larger than that of group I (14.6 +/- 5.7 mm2, P < 0.01). Plaque calcification was found in 25% of those in group III and 44% of those in group IV. Thus, only 36% of the patients with normal angiograms were true normal, 48% exhibited early stage of coronary atherosclerosis, and the other 16% might be considered as syndrome X. CONCLUSION: Intracoronary ultrasound and Doppler can be used to differentiate further heart disease in patients with normal coronary angiograms. Only a minority were true normal. Early signs of atherosclerosis cannot be detected by coronary angiography. This may have important therapeutic and prognostic implications.  相似文献   

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