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941.
Three-dimensional (3-D) ultrasound (US) has greatly improved evaluation of organ circulation. The aim of this study was to explore the possible use of this new technique in normal and high-risk pregnancies. Fetal brain, lung and placenta 3-D power Doppler signal intensity were recorded in 115 normal singleton pregnancies (24 to 42 weeks gestation) and in 67 high-risk pregnancies. Mean image pixel signal intensity was calculated for each organ and a brain-lung ratio. In normal pregnancy, placental and lung signal intensity increased until 33, with a rapid decrease after 38, weeks of gestation. Fetal cerebral signal intensity increased with gestational age. Placental and fetal lung signal intensity was significantly lower in high-risk pregnancies than in the control group, with increased fetal brain and brain-lung ratios. The present results suggest a reduction of placental perfusion after 38 weeks of gestation in normal pregnancy, with redistribution of fetal circulation. Lung signal intensity increased abruptly at 32 weeks of gestation, which might reflect lung maturity. The new method showed signs of centralization of fetal circulation at the end of gestation. The results might suggest a possible clinical use for fetal surveillance in high-risk pregnancies.  相似文献   
942.
943.
The current status of living donor liver transplantation   总被引:7,自引:0,他引:7  
In response to the critical organ shortage, transplant professionals have utilized living donors in an attempt to decrease the mortality rate associated with waiting on the liver transplant list. Although the surgical techniques were first utilized clinically 15 years ago, application of LDLT has been somewhat limited by the steep learning curve associated with developing a program. Clinical success with LDLT in children was realized early in the experience and application of the techniques to the adult population has occurred more recently. Although transplant centers embark on LDLT with enthusiasm, the safety of the donor must always be at the forefront of the process. Potential donors must come to the decision to donate without pressure from members of the family or transplant team. He/she should also be assigned advocates who constantly promote the donor's best interest. Failure to adhere to strict donor evaluation protocols and standardized operative techniques could result in disastrous consequences.  相似文献   
944.
OBJECTIVE: To report seven cases of vascular repair of the internal carotid artery (ICA) using a modified Fisch type A infratemporal approach and a venous grafting. STUDY DESIGN: Retrospective case review. SETTING: Tertiary care center. PATIENTS: We have analyzed the clinical presentation, paraclinical assessment, and postoperative results regarding the vascular repair and the facial and auditory function from seven consecutive patients. All patients have been operated on by a multidisciplinary team of ENT and vascular surgeons. RESULTS: The study includes four men and three women, aged from 21 to 62 years old. Six patients suffered from vascular traumatic injury after motor vehicle accident (n = 5) or cervical manipulation (n = 1) and one patient presented an atheromatous stenosis. All benefited from a vascular repair with a venous grafting through a modified Fisch Type A infratemporal approach. No death and no new stroke were noted (mean follow-up, 34 mo). The postoperative angiographies showed six functional grafts and one asymptomatic thrombosis. Six immediate postoperative facial palsy occurred but recovered to Grade I or II within 6 months. There was one traumatic injury of the facial nerve and one postoperative anacusis. For the six other patients, the reconstitution of the external auditory canal and ossicular chain allowed to limit the hearing loss to a mean air-bone gap of 22.5 dB (range, 15-35 dB). CONCLUSION: The lesions of the intrapetrous aspects of the ICA remain the subject of debates regarding the indication for a vascular repair. For young or in good health patients, the infratemporal approach provides a safe and reliable access to the horizontal segment of the ICA, offering to the vascular surgeons optimal conditions for the vascular repair.  相似文献   
945.
A biogenetic-type synthesis of (+)-cymbodiacetal (1), a novel bismonoterpenoid dihemiacetal, is described.  相似文献   
946.
AIM: To determine effectiveness of treatment for hepatitis C outside clinical trials, by testing the hypothesis that apparent effectiveness and tolerability of interferon alfa-2b/ribavirin combination therapy would be less in a hospital liver clinic setting. DESIGN: Retrospective analysis of all patients in one centre commencing interferon alfa-2b/ribavirin therapy, but not in clinical trials, between 1998 and 2000. MAIN OUTCOME MEASURES: Effectiveness as sustained virological response (SVR); tolerability as premature discontinuation of treatment. RESULTS: The 121 patients had similar demographic and viral characteristics as those in Australian trials (age, 44 +/- 10 years; males, 66%; genotype 1, 44%; genotype 3, 36%), but 38% had advanced fibrosis, including 17% with cirrhosis. Sixty (50%) were previously untreated, 38 (31%) had relapsed after initial response (response relapse) and 23 (19%) were non-responders to interferon monotherapy. Sustained viral response (SVR) was achieved in 53% of patients overall: 47% of patients with genotype 1 HCV, 71% of patients with genotype 3. For patients with genotype 1 HCV, SVR was 43% in those previously untreated, 63% in response relapsers, and 38% in non-responders. Corresponding SVRs for genotype 3 were 65%, 87% and 33%. These results are similar to those obtained in published trials. Only 7% of our patients discontinued treatment because of adverse effects, fewer than reported in most clinical trials. Dose reduction was required in 18% of patients. CONCLUSIONS: In a hospital clinic setting the effectiveness of interferon alfa-2b/ribavirin combination therapy appears equivalent to published results from clinical trials.  相似文献   
947.
AIM OF THIS STUDY: Hypokaliemic thyrotoxic periodic paralysis (HTPP) is an uncommon complication of hypothyroidism. Mostly described among Asian patients, it is rare in the other ethnic groups, in particular in caucasians people. Among the possible mechanisms, modification of potassic flows in relation to anomalies of the sodium-potassium pump were evoked. PATIENTS AND METHOD: We present the cases of three caucasians patients operated on for HTPP. These patients had all previous history of several paretic episodes. The flask paralytic attacks occurred in a brutal way or were preceded by diffuse myalgias. They reached the proximal muscles, especially in inferior limbs. No patient had any respiratory complications. These three patients underwent total thyroidectomy to treat the symptoms of HTPP. RESULTS: In the three cases, a total thyroidectomy allowed the recovery of the symptoms. After a four years average period of post-operative follow-up, no patient presented any repetition of HTPP. The hyperthyroidism is the cause of decompensation of the molecular anomaly. CONCLUSION: In our opinion, surgical treatment (total thyroidectomy) is needed in order to reduce the potential gravity of this pathology.  相似文献   
948.
Aim: To describe and review the differential diagnosis of epididymal nodules and chronic epididymitis so as to have a broad view of this pathology. We have suggested a possible diagnostic algorithm for the workup of an epididymal nodule.Methods/results: We have reported a case of a 35-year-old patient with a symptomatic palpable nodular mass in the tail of the left epididymis. Fine needle aspiration suggested an adenomatoid tumor while the surgical excision histology was reported as chronic epididymitis.Conclusions: Epididymal nodules are frequently encountered in the epididymis. Their differential diagnosis includes chronic granulomatous epididymitis, adenomatoid tumor and benign paratesticular neoplasms. We consider that it is important to distinguish epididymal nodules from benign inflammatory lesions and the threshold for a surgical excision should be low as it is therapeutic and provides a definite diagnosis. Whilst the FNAC alone may not be always adequate to confirm diagnosis, an epididymectomy may be curative as well as diagnostic in selected cases.  相似文献   
949.
Learning anatomy and surgical procedures requires both a conceptual understanding of three-dimensional anatomy and a hands-on manipulation of tools and tissue. Such virtual resources are not available widely, are expensive, and may be culturally disallowed. Simulation technology, using high-performance computers and graphics, permits realistic real-time display of anatomy. Haptics technology supports the ability to probe and feel this virtual anatomy through the use of virtual tools. The Internet permits world-wide access to resources. We have brought together high-performance servers and high-bandwidth communication using the Next Generation Internet and complex bimanual haptics to simulate a tool-based learning environment for wide use. This article presents the technologic basis of this environment and some evaluation of its use in the gross anatomy course at Stanford University.Media-rich learning experiences are widely available on the web. Medical schools and other health care organizations maintain extensive websites for learning, reference, and assessment. Continuing medical education on the Internet is one of the most commonly available and widely used services for health care practitioners. These media-based learning environments, though widely available, represent a passive medium of information retrieval by clicking a mouse.We have been investigating the next generation of Internet-based learning technologies: simulation-oriented learning environments that support interaction, collaboration, and active learning. The topics of learning are anatomy and basic surgical manipulations. To support these topics, we have developed three-dimensional visualizations of anatomy and have enriched these anatomical models with biomechanical tissue properties of elasticity and viscosity such that the learner can use appropriate force-feedback tools to feel tissues at the same time that they visualize them. Access to and interaction with these simulation environments have required that we push the envelope of current Internet capabilities, and that we investigate the role of network bandwidth and latency in the performance of these applications. A preliminary version of this work was presented at MedInfo, 2001.1  相似文献   
950.
Hepatitis C virus (HCV) genotype and other host and viral factors influence treatment outcome in chronic HCV infection. We evaluated the effect of race and genotype on interferon and ribavirin treatment outcome in 70 Southeast Asian (SEA) and 50 white patients. Genotype was based on the 5' untranslated region (5'UTR) with a commonly used line probe assay (INNO-LiPA HCV II) that may mistype genotype 7, 8, or 9 as 1b. HCV core region sequencing resulted in reclassification of 8 genotype 1 and 25 genotype 1b SEA subjects as genotype 7, 8, or 9. Twenty-six SEA genotype 7, 8, and 9 (79%) and 10 SEA true genotype 1b (59%) patients achieved a sustained virologic response (SVR) compared with 15 (34%) white genotype 1b patients. Logistic regression analysis showed that SEA patients with genotype 7, 8, or 9 were more likely to achieve a SVR than white genotype 1b patients (OR 16.56; 95%CI 4.16, 65.91) as were SEA true genotype 1b patients compared with white genotype 1b patients (OR 4.63; 95%CI 1.19, 18.04). In conclusion, a proportion of SEA patients classified by INNO-LiPA as genotype 1b were in reality genotype 7, 8, or 9. In comparison with white genotype 1b patients, both SEA genotype 1b and SEA genotype 7, 8, and 9 patients showed a significantly greater SVR. HCV core sequencing was necessary to determine genotype accurately in persons potentially exposed to HCV genotypes 7, 8, or 9. This study also supports the concept that race and ethnicity are important determinants of treatment outcome in HCV infected patients.  相似文献   
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