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The various methods of prefabricating flaps include vascular induction through staged transfer; pretransfer delay, expansion, and grafting; the use of alloplastic materials; and tissue bioengineering. In this experimental study, vascular induction was used to provide an axial vascular pedicle to randomly nourished tissue. Twenty-six New Zealand rabbits, ages and weights ranging between 6 months-1 year and 1.5-3.5 kg, respectively, were used. The sex difference was not considered. The deep inferior epigastric artery and vein were used to carry blood and were placed into a segment of femur to prefabricate the bone. Four weeks later, the viability of the segment of bone prefabricated by new axial pedicle was shown by scintigraphic study, and the new axial pedicle was ready for free transfer.  相似文献   
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髁突形态与覆深度关系的研究   总被引:1,自引:0,他引:1  
目的 探讨髁突形态与不同覆深度的关系。方法 选择正常者、开畸形患者、覆正常的错畸形患者和深覆畸形患者各 5 0人 ,均为 18至 2 6岁成人。应用曲面断层片研究左右两侧的髁突形态 ,分别测量并计算上部髁突高度 /升支高度比 (UCH/RH)和髁突高度 /宽度比 (TCH/CW )。将髁突形态分为四种类型 :直立型 (类A) ,前倾型 (类B) ,后倾型 (类C)和尖型 (类D)。结果 开组的上部髁突高度相对升支高度明显小于其他各组 (P <0 0 0 1)。正常组的髁突形态比较粗壮 ,高度宽度比明显小于其他各组 (P <0 0 0 1)。类A和类B属于正常髁突形态 ,占正常组的 99%。类C和类D属于异常髁突形态 ,且在开组中的比例明显高于正常覆组或深覆组。另外 ,只有开组中显示上部髁突高度两侧不对称 (P <0 0 5 )。结论 开组髁突形态与其他各组相比明显不同。  相似文献   
4.
First branchial cleft fistula is a rare congenital malformation of the head and neck with an incidence of less than 10% of all branchial cleft defects. We herein report a 15-year-old girl who had a cystic mass in the postauricular region with an external opening on the posterior face of the earlobe. Surgical exploration revealed that a second sinus tract was passing through the conchal cartilage without going beyond the skin of the external acoustic meatus. The mass and the tract were excised along with the opening on the earlobe as well as the skin island surrounding the opening. The case was treated surgically with success .The significance of our case was the location of external opening on the earlobe.  相似文献   
5.
In dentistry, acrylates have been used for preparing denture bases for 50 years. Although polymethylmethacrylates (PMMA) are known to be an ideal base material, they possess some undesirable mechanical properties, especially their impact strength and tensile strength, which appear to be unsatisfactory for some applications. Additives and fibers have therefore been used to enhance and improve these properties over the last two decades. The present article describes the mechanical properties, impact and tensile strength of PMMA reinforced with chopped ultra-high molecular weight polyethylene fiber (6 mm long). It was found that, although the processing involved for high loading of fibers into the PMMA was difficult, the resulting improvement of impact strength was substantial.  相似文献   
6.
BACKGROUND: Hypothermic conditions required for donor heart preservation may reduce gene-transfer efficiency. Experiments were designed to determine whether a perfusion technique could improve the efficiency of gene transfer to donor hearts. METHODS: An adenoviral vector encoding beta-galactosidase (3.5 x 10(8) plaque-forming units) was infused into explanted rat hearts under 4 conditions (each n = 6): (1) the virus was diluted in 350 microL of University of Wisconsin solution and infused as a high-pressure bolus into the coronary arteries of donor hearts through the aortic root; (2) the virus was diluted in 5 mL of University of Wisconsin solution and circulated by means of a peristaltic pump (flow, 0.75 mL/min) through the vasculature of the donor heart for 30 minutes; (3) 5 mL of viral solution was circulated as for group 2 for 15 minutes; and (4) 5 mL of viral solution was circulated for 5 minutes at a flow rate of 2.4 mL/min. Transduced hearts were transplanted into the abdomen of syngeneic rats, and transgene expression was assessed by means of immunoassay 4 days later. RESULTS: The median beta-galactosidase content was (1) 45.0 ng/mg protein (25th-75th percentile, 33-73 ng/mg), (2) 640 ng/mg protein (25th-75th percentile, 614-878 ng/mg), (3) 493.8 ng/mg protein (25th-75th percentile, 456-527 ng/mg), and (4) 503.3 ng/mg protein (25th-75th percentile, 475-562 ng/mg; P <.01 for group 2 vs group 1, and P <.05 for groups 3 and 4 vs group 1). Transgene expression was predominantly in myocytes and favored the subepicardial region of the right ventricle. CONCLUSION: Hypothermic perfusion of the donor heart with an adenoviral vector resulted in efficient transgene expression compared with that induced by a single bolus injection.  相似文献   
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Gastric emptying time measurement by radionuclide study, although quite informative, is rarely remembered in clinical practice. We presented a patient with brittle diabetes who had multiple emergency admissions due to hypoglycemia under routinely prescribed insulin therapy. She had severe gastroparesis, which was determined by scintigraphic gastric emptying study (gastric half-emptying time = 260 min for a mixed meal). She had not presented to the emergency service for two years because of only a slight change the timing of her insulin administration time (after meal instead of before meal) in the light of gastric-emptying study.  相似文献   
9.
OBJECTIVE: ADC calculation can improve the diagnostic efficacy of MR imaging in brain tumor grading and differentiation. METHODS: Apparent diffusion coefficient (ADC) values and ratios of 33 low-grade (23 astrocytomas, 10 oligodendrogliomas) and 40 high-grade (25 metastases and 15 high-grade astrocytomas) malignant tumors were prospectively evaluated. RESULTS: Tumoral ADC values (r=-0.738, P <0.000) and ratios (r=-0.746, P < 0.000) were well correlated with higher degree of malignancy and quite effective in grading of malignant brain tumors (P < 0.000). By using cutoff values of 0.99 for tumoral ADC value and 1.22 for normalized ADC ratio, the sensitivity of MR imaging could be increased from 72.22% to 93.75% and 90.63%, the specificity from 81.08% to 92.68% and 90.24%, PPV from 78.79% to 90.91% and 87.88%, and NPV from 75.00% to 95.00% and 92.50%, respectively. CONCLUSION: ADC calculation was quite effective in grading of malignant brain tumors but not in differentiation of them and added more information to conventional contrast-enhanced MR imaging.  相似文献   
10.
IntroductionSubchorionic hematoma (SCH) in pregnancy has been associated with increased risk of adverse pregnancy outcomes. We aimed to investigate the association of SCH with adverse pregnancy outcomes in pregnant women in relation to size of hematoma and control subjects.Material and methodsThis study included 178 pregnant women with sono-graphically detected SCH in the 1st trimester, and 350 pregnant controls without SCH. Data on maternal age, smoking status, gestational week at diagnosis, location of SCH, medications before diagnosis, gestational week at delivery, delivery route and pregnancy outcomes (first trimester vaginal bleeding, pre-eclampsia, gestational diabetes, intrauterine growth restriction (IUGR), placental abruption, preterm delivery < 37 weeks, early pregnancy loss and intrauterine death) were retrieved retrospectively from hospital records. Pregnant women with SCH were divided into 3 groups according to the size of hematoma including small SCH (SCH-I group, n = 47), medium-size SCH (SCH-II group, n = 110) and large SCH (SCH-III group, n = 21) groups.ResultsSubchorionic hematoma was associated with significantly lower gestational age at delivery (p < 0.001) and higher rate of first trimester bleeding (p < 0.001) compared with the control group, regardless of the size of the hematoma. Placental abruption (p = 0.002) and early pregnancy loss (p < 0.001) were significantly more common in SCH-II and -III groups than in the control group. SCH-III group was associated with a significantly higher rate of < 37 gestational weeks at delivery (p < 0.001), first trimester vaginal bleeding (p < 0.001), early pregnancy loss (p < 0.001), IUGR (p = 0.003) and preterm delivery (p < 0.001) compared to both lesser size hematoma and control groups.ConclusionsOur findings suggest that large SCH might indicate an increased risk of adverse pregnancy outcomes such as 1st trimester vaginal bleeding, early pregnancy loss, IUGR, placental abruption or preterm delivery. These findings are important to guide the patients with SCH for detailed clinical evaluation.  相似文献   
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