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971.
对56例T型管胆道造影的X线征象进行了分析,论述了有关征象的诊断及依据,并着重阐述了易被忽视的现象及误诊原因。  相似文献   
972.
The conformity of a pre-shaped endotracheal tube to the shape of the airway during endotracheal intubation was studied from lateral radiographs in patients lying supine on the operating table, with the neck in the normal, extended and flexed positions. A computer programme calculated the anterior contour of the pre-shaped tube and the posterior contour of the airway as mean values of the original contours on the radiographs. The mean configuration of the airway in intubated individuals with a pre-shaped endotracheal tube was then presented in a standard coordinate system. The results were compared with the shape of the airway in non-intubated patients and in patients intubated with a standard endotracheal tube.  相似文献   
973.
本文就PAR及PAgT种方法,用ADP作致聚剂,对血小板聚集功能亢进与血小板聚集功能低下的两类患者在临床应用上进行比较。实验结果说明,对血小板聚集功能亢进的患者PAR试验敏感性比PAgT高,实验结果较客观,且能较好地反映血小板聚集的全过程。但标本脂血对实验结果有影响。PAgT尚具有一定的试验敏感性,由于其不需特殊仪器,简便易行,且不受标本脂血的影响,故仍不失为基层单位初步的筛选方法。在7例肝硬化患者中,由PAR所检出的血小板聚集功能低下的3例,PAgT却均正常,未能检出,故对肝硬化患者,不宜采用PAgT法。  相似文献   
974.
本文报道我科62例神经管缺陷畸形的B型超声检查,其中无脑儿38例,单纯脊柱裂2例,无脑儿合并脊柱裂11例,脑积水4例,脑膜及脑脊髓脊膜膨出7例。62例神经管缺陷中有32例在本院分娩,得以证实均为神经管缺陷几,其余30例失访。本文对B型超声诊断神经管缺陷的要点,羊水量与神经管缺陷的关系及脑积水儿双顶间径的大小对诊断的意义进行了探讨。  相似文献   
975.
Splotch (Sp/Sp) mice homozygous for a mutation in the Pax3 gene inevitably present with neural tube defects (NTDs), along with other associated congenital anomalies. The affected mutant embryos usually die by gestation days (E) 12-13. In the present study, the effect of modifier genes from a new genetic background (CXL-Sp) and periconceptional supplementation with selected micronutrients (folic acid, 5-formyltetrahydrofolate, 5-methyltetrahydrofolate, methionine, myoinositol, thiamine, thymidine, and alpha-tocopherol) was determined with respect to the incidence of NTDs. In order to explore how different exposure parameters (time, dose, and route of compound administration) modulate the beneficial effects of micronutrient supplementation, female mice received either short- or long-term nutrient supplements via enteral or parenteral routes. Embryos were collected on E12.5 and examined for the presence of anterior or posterior NTDs. Additionally, whole mount in situ hybridization studies were conducted in order to reveal/confirm normal expression patterns of the Pax3 gene during neurulation in the wild-type and Sp/Sp homozygous mutant mouse embryos utilized in this study. A strong Pax3 signal was demonstrated in CXL-Sp embryos during neural tube closure (E9.5 to E10.5). The intensity and spatial pattern of expression were similar to other Splotch mutant mice. Of all the micronutrients tested, only supplementation with folic acid or 5-methyltetrahydrofolate rescued the normal phenotype in Sp/Sp embryos. When the folate supplementation dose was increased to 200 mg/kg in the diet, the incidence of rescued splotch homozygotes reached 30%; however, this was accompanied by six-fold increased resorption rate.  相似文献   
976.
Shanxi province in Northern China has one of the highest reported prevalence rates of neural tube defects (NTD) in the world. To explore the risk factors for NTDs in Shanxi province, we carried out a population-based case-control study in four selected counties with prevalence rates >10 per 1000 births during 2003. Using a multi-logistic regression model analysis (alpha = 0.10), 158 NTD cases were compared with 226 control mothers. Maternal factors significantly associated with increased risk for an NTD were a primary school education or lower (adjusted odds ratio [OR] 2.32, 95% confidence interval [CI] 1.09, 4.97); a history of a previous birth defect-affected pregnancy (adjusted OR 5.27, 95% CI 0.98, 28.37); history of a fever or 'cold' (adjusted OR 3.36, 95% CI 1.68, 6.72); use of analgesic and antipyretic drugs (adjusted OR 4.89, 95% CI 0.92, 25.97); daily passive exposure to cigarette smoke (adjusted OR 1.60, 95% CI 0.94, 2.73); poor ventilation during heating (adjusted OR 3.91, 95% CI 0.75, 20.81); and consumption of >or= six meals per week containing pickled vegetables (adjusted OR 3.86, 95% CI 1.11, 13.47) during pregnancy. Factors which appeared to be protective were meat consumption one to three times per week (adjusted OR 0.62, 95% CI 0.37, 1.06), or >or= four times per week (adjusted OR 0.28, 95% CI 0.11, 0.77); and legume consumption >or= six times per week (adjusted OR 0.39, 95% CI 0.17, 0.89). Differences in risk were found between the two most common phenotypes, anencephaly and spina bifida. Most of the environmental factors had stronger positive and negative associations with risk for anencephaly rather than spina bifida, whereas history of a previous birth defect-associated pregnancy, as well as legume consumption, were more strongly associated with the risk for spina bifida than for anencephaly. The findings suggest that aetiological heterogeneity may exist between anencephaly and spina bifida.  相似文献   
977.
Mexico-born women in the United States have an unexplained twofold increased risk of neural tube defect (NTD)-affected pregnancies. We examined whether immigration characteristics were associated with the NTD risk and whether anthropometric factors contributed to the increased risk among Mexico-born women. Data were derived from a large population-based case-control study in California. In-person interviews were conducted with mothers of 538 (88% of eligible) NTD-affected fetuses/infants and mothers of 539 (88%) randomly selected non-malformed control infants. The crude odds ratio (OR) for NTDs among all Mexico-born women, women residing <2 years in the US, and women >16 years old at immigration compared with non-Hispanic white women was 2.4 [95% confidence interval (CI) = 1.8, 3.3], 7.2 [95% CI = 3.7, 14.0] and 3.0 [95% CI = 2.0, 4.4], respectively. Risk for second- or third-generation Mexican-Americans was similar to that of white women. The crude OR for all Mexico-born women was reduced from 2.4 to 2.0 [95% CI = 1.3, 3.0] and for those residing <2 years in the US from 8.4 to 7.1 [95% CI = 3.2, 15.3] after adjustment for maternal body mass index (BMI), height, compromised diet, diabetes, and other known risk factors. In term pregnancies, additional adjustment for pregnancy weight gain reduced the OR in all Mexico-born women and recent immigrants by 16% and 25%, respectively. Low pregnancy weight gain (<10 vs. 10-14 kg) was particularly associated with increased NTD risk among Mexico-born women (OR(ADJ) = 5.8; 95% CI = 2.1, 15.8). Findings indicate that recent Mexican immigrants have a sevenfold increased risk for NTDs. Maternal BMI and height contributed very little, and inadequate weight gain contributed modestly to the NTD risk disparity for Mexican immigrants.  相似文献   
978.
This case report describes the use of a bronchial blocker (BB) with a wheel-controlled tip (Cohen flexitip endobronchial blocker) to provide initially middle and lower right lobe isolation and then right lung isolation (RLI) during right lower lobectomy in a patient with compromised pulmonary function preoperatively. As predicted, RLI and one-lung ventilation were associated with worsening oxygenation. Toward the end of the surgery, RLI was converted back to middle and lower right lobe isolation and oxygenation returned to normal levels. The BB design made lobar isolation easier and enabled repositioning of the BB during surgery. The techniques used for BB insertion as well as lobar and lung separation are described.  相似文献   
979.
BACKGROUND: In this study, we evaluated the ratio of the cuff diameters of the Microcuff paediatric tracheal tube (Microcuff PET, Weinheim, Germany) to fluoroscopically measured internal transverse tracheal diameters in children from birth to adolescence. METHODS: With Institutional Ethics Committee approval and parental consent, we measured the internal transverse tracheal diameters from fluoroscopy images in children undergoing cardiac catheterization requiring general anaesthesia with oro-tracheal intubation. Minimal tracheal sealing pressures were assessed at standardized respirator settings. Internal transverse tracheal diameters were compared with cuff diameters at 20 cmH2O cuff pressure. Linear regression analysis was employed to assess the correlation of tracheal diameters with age, height and weight, and to assess the correlation of the cuff/tracheal diameter ratio with sealing pressures. For all tests, P < 0.05 was considered to be statistically significant. RESULTS: One hundred and forty-five patients were studied (62 girls; 83 boys). Transverse tracheal diameters correlated well with age (r = 0.890; P < 0.0001), height (r = 0.900; P < 0.0001) and weight (r = 0.882; P < 0.0001). Tracheal sealing pressures ranged from 4 to 18 cmH2O. The ratio of the tracheal tube cuff diameter to the internal transverse tracheal diameter ranged from 1.06 in tubes with internal diameters of 6.0 and 4.5 mm to 2.01 in a tube with an internal diameter of 3.5 mm (median, 1.43), and did not correlate with tracheal sealing pressures (r = 0.021, P = 0.7999). CONCLUSIONS: The residual diameters of the Microcuff paediatric tracheal tube cuffs were sufficient to cover the measured internal transverse tracheal diameters of children from birth to adolescence. This allowed the internal tracheal mucosal surface to be draped and the trachea to be sealed at very low cuff pressures.  相似文献   
980.
Benefits of early aggressive management of empyema thoracis   总被引:3,自引:0,他引:3  
BACKGROUND: The end-target of the management of thoracic empyema is to obtain early rehabilitation by re-expansion of the trapped lung resulting from intrapleural infected material. Our aim was to shorten the hospitalization time and to prevent a possible thoracotomy by using video-assisted thoracoscopy initially. METHODS: Seventy patients with parapneumonic empyema were prospectively studied between January 1997 and June 2004. The patients were randomly divided into two groups. In group I (n = 35 patients), a chest tube was inserted into the patients after pleural content was evacuated and fibrins were debrided using video-assisted thoracoscopy. In group II (n = 35 patients), tube thoracostomy was carried out without using a video-assisted thoracoscope. Both groups were compared in terms of hospitalization time, open surgery for decortication and complications. RESULTS: There was no statistically significant difference between the groups from the point of view of age and sex (P > 0.05). In group I, 17.1% of the patients underwent open decortication, whereas in group II, 37.1% of the patients underwent the same procedure (P < 0.05). Whereas average hospital stay in group I was 8.3 days (range, 7-11 days), it was 12.8 days in group II (range, 10-18 days; P < 0.05). There was one bronchopleural fistula in group I, and there was one bronchopleural fistula and one death in group II. CONCLUSION: Video-assisted thoracoscopic evacuation and chest tube insertion in situ is a new therapeutic approach for pleural empyema that shortens hospital stay and reduces the necessity of open decortication.  相似文献   
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