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21.
Reversal of diastolic cerebral blood flow in infants without brain death   总被引:1,自引:0,他引:1  
The reversal of diastolic cerebral blood flow has been regarded as a characteristic waveform of brain death and a useful confirming sign. We report 2 patients who had diastolic flow reversal but survived. One, a 1-month-old boy with status epilepticus, had reversal of diastolic cerebral blood flow detected by Doppler ultrasound soon after admission. Reversal disappeared after medical management for increased intracranial pressure and seizure control. He recovered without sequelae. The other, a 6-month-old girl with choroid plexus papilloma, had reversal of diastolic flow during abrupt clinical deterioration. Emergent surgical removal of the tumor was performed and she survived with hemiparesis and psychomotor retardation. Our patients demonstrated that even in the presence of diastolic reversal of cerebral blood flow, prompt and effective treatment can avoid a fatal outcome.  相似文献   
22.
Laparoscopic nephrectomy was performed in 15 male pigs, the procedure was successful in 14. Extraction of the intact kidney through a 5-cm lower abdomen incision was done in 7 animals; complete destruction and evacuation of the kidney was accomplished by a round-knife suction device through a 1-cm port in another 7 pigs. Grossly, the specimen consisted of sausage-like tubular renal tissue and a small amount of tissue debris. Pathology revealed that the glomerular and tubular structures were well preserved, no interstitial hematoma could be found. Four ports were usually used, one 1-cm umbilical camera port, one 0.5-cm port for ureter traction, and two 1-cm working ports along the midclavicular line. All the pigs recovered uneventfully. The average operation time was 3 h 20 min. The application of endo-GIA (United States Surgical Corporation) for renal hilum reduced the operative time to 2 h 20 min. Complications included renal vein tear during endoclip application and cutting in the first case, mild subcutaneous emphysema in 2 cases. This first pig received exploratory laparotomy for the repair and ligation of the renal vein. No more major complications occurred with increasing experience. From this porcine experiment, we conclude that the combination of laparoscopy, a tissue destroyer and an endobag for the entrapment of kidney seem to be a promising technique for clinical nephrectomy.  相似文献   
23.
获得性纯红再障患者外周血T细胞亚群分析   总被引:7,自引:0,他引:7  
目的 本研究通过分析获得性纯红再障患者外周血T细胞亚群 ,进一步探讨该病的细胞免疫发病机制。方法 用抗人CD3、CD4、CD8、IFN γ及IL 4单抗结合人外周血单个核细胞 ,流式细胞术分析单个核细胞中CD3 +、CD4+、CD8+细胞数Th1、Th2、Tc1、Tc2细胞数以及CD4+/CD8+、Th1/Th2、Tc1/Tc2比值。结果 贫血组患者 ,外周血CD3 +细胞和CD8+细胞明显增加 (P <0 .0 1) ,CD4+/CD8+比例倒置 (P <0 .0 5 ) ;Tc2细胞明显增加 (P <0 .0 5 ) ,Tc1/Tc2比值降低(P <0 .0 5 ) ,治疗后血象恢复的患者各增高的亚群细胞均有所恢复 ,接近正常。结论 在获得性纯红再障患者T细胞明显增高 ,其中主要是CD8+细胞 ,而在CD8+细胞中 ,是Tc2细胞发挥了重要作用。经治疗有效的患者 ,其增高的T细胞亚群降低 ,提示以纠正病人细胞免疫异常为主的治疗方案有益于获得性纯红再障的治疗。  相似文献   
24.
现察口腔修复临床电刀龈成形术的效果。方法:对81例口腔修复门诊牙体缺损患者用电刀进行牙龈成形术并定期复诊观察。结果:81例术后牙龈全部达到修复要求而立即修复,其中70例术后牙龈稳定,占总数的86.4%。结论:电刀龈成形术是口腔修复临床上一种可行的治疗手段。  相似文献   
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26.
BACKGROUND: Although it has been reported that ghost cells are present in odontomas, the generation mechanism of these cells is unclear. To evaluate the presence of ghost cells and involvement of the Wnt signaling pathway, we examined the expression of hard keratins, beta-catenin and Lef-1 in odontomas. METHODS: Sixty-nine cases of odontoma were examined immunohistochemically with the use of antibodies against human hair proteins, beta-catenin and Lef-1. RESULTS: Expression of hard keratins was found only in the cytoplasm of ghost cells in 46 (66.7%) of the 69 odontomas. Compound odontomas (78.8%) showed a higher incidence of ghost cells than complex odontomas (29.4%). Histopathologically, ghost cells were found within odontogenic epithelium adjacent to immature enamel and in the centre of Liesegang-ring-like calcified materials. Expression of beta-catenin and Lef-1 was observed in the cytoplasm and nucleus of odontogenic epithelial cells adjacent to the ghost cells in immature odontomas. CONCLUSION: These findings suggest that odontoma is a hard keratin-expressing tumor-like lesion, and that the Wnt signaling pathway may be involved in the formation of ghost cells in odontomas.  相似文献   
27.
Metastatic septic endophthalmitis in pyogenic liver abscess   总被引:4,自引:0,他引:4  
In a consecutive series of 180 patients with pyogenic liver abscess, three patients (two men and one woman, between 46 and 75 years of age) had metastatic Klebsiella endophthalmitis. The incidence of metastatic endophthalmitis was 1.7% in patients with pyogenic liver abscess, 5.2% in patients with Klebsiella liver abscess, and 7.8% in patients with Klebsiella liver abscess having Klebsiella bacteremia. Despite aggressive therapeutic measures, the men permanently lost their vision and the woman eventually required an evisceration of her right eye. Delayed recognition and/or treatment as well as the nature of bacteria probably contributed to the tragic outcome. The findings suggest that a high index of suspicion is critical and a combined effort of the internist and ophthalmologist is mandatory.  相似文献   
28.
Glucokinase gene is genetic marker for NIDDM in American blacks.   总被引:13,自引:0,他引:13  
Glucokinase (ATP:D-glucose-6-phosphotransferase), expressed exclusively in liver and pancreatic islet beta-cells, catalyzes the first step of glycolysis and acts as glucose sensor and metabolic signal generator in these tissues. The enzyme plays a key role in glucose homeostasis and as such is an excellent candidate for inherited defects predisposing to non-insulin-dependent diabetes mellitus (NIDDM). A compound-imperfect dinucleotide (CA)n repeat element was found approximately 10-kb 3' of the human glucokinase gene on chromosome 7p, which revealed polymorphism with alleles differing in size by 2-15 nucleotides in unrelated individuals. A polymerase chain reaction assay was developed, and genomic DNA from 275 biologically unrelated American black individuals was typed for glucokinase alleles. The differences in allelic frequencies between individuals with NIDDM and nondiabetic individuals were compared. After typing 112 diabetic and 163 nondiabetic subjects, we found five different-sized alleles, with Z defined as the most common allele, Z + 2, Z + 4, Z + 10, and Z - 15. The Z allele was more common in nondiabetic subjects than in diabetic patients (60.4 vs. 49.6%, P = 0.012). The Z + 4 allele was more common in diabetic patients than in nondiabetic subjects (20.1 vs. 12.0%, P = 0.009). After adjusting for age, sex, and body mass index, the Z + 4 allele continued to have a positive association with NIDDM (P = 0.0018), and the Z allele had a negative association with NIDDM (P = 0.0334). The Z + 4 allele, transmitted as an autosomal dominant trait, appeared to be the most significant one at this locus.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
29.
We investigated whether weight loss decreases the waist-hip ratio (WHR) in overweight men and women, and whether changes in WHR relates to change in cardiovascular risk factors, independent of change in weight. Weight loss correlated significantly with decreases in the circumference of the waist and hips, and decreases in WHR in men and women. At comparable levels of weight loss, men had greater decreases in the waist, and smaller decreases in the hips than women, resulting in greater decreases in WHR. Cardiovascular risk factors improved significantly with weight loss. However, after controlling for weight loss, there was no evidence that change in WHR or change in circumference measures were related to change in risk factors. These data suggest that WHR is modifiable by weight loss, especially in men, but that change in WHR may not be independently related to changes in cardiovascular risk factors.  相似文献   
30.
The rates of remission after a course of antithyroid drugs in 71 black and 45 white patients with Graves' disease were compared. One year after stopping therapy 27% of blacks and 47% of whites were in remission (P less than 0.01); at 2 years the proportions were 7% and 27% respectively (P less than 0.05). Small size of goitre only was a weak predictor of remission; duration of therapy did not influence the outcome. HLA A2 and B17 may be less frequent in black patients who remain in remission (P = 0.048 and 0.067 respectively). The data suggest that it is not worth while undertaking a trial of medical therapy in unselected black patients with Graves' disease.  相似文献   
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