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81.
The invasive nature of endomyocardial biopsy has led to a search for alternative diagnostic modalities for the detection of cardiac allograft rejection. To date, no non-invasive test meets all the requirements for the detection of acute and chronic rejection. The rejection process usually presents with lymphocyte infiltration with or without myocyte necrosis, which indicates the severity of cardiac allograft rejection and the necessity of treatment. Activated lymphocytes express somatostatin receptors; thus somatostatin receptor imaging could be used to target them. The aim of this study was to assess the feasibility of using somatostatin receptor imaging to target activated lymphocytes in the process of cardiac allograft rejection. Thirteen somatostatin receptor imaging studies were performed on ten cardiac allograft recipients 12-4,745 days after transplantation, simultaneously with endomyocardial biopsy, to assess the imaging of activated lymphocytes in comparison with histological findings. Somatostatin receptor imaging was performed 4 h after the injection of 110 MBq of the somatostatin analogue indium-111 pentetreotide. 111In-pentetreotide uptake was visually scored and semi-quantitatively estimated by the calculation of a heart-to-lung ratio (HLR). The visual score correlated with the HLR. Intense/moderate uptake on visual assessment and an HLR >1.6 was observed in eight studies. In three of these studies there was significant rejection in the simultaneous endomyocardial biopsy [International Society of Heart and Lung Transplantation (ISHLT) rejection grade 3A/4]. Intense/moderate uptake was associated with mild or no rejection in the remaining five patients, and in four of them the next endomyocardial biopsy performed 1 week later demonstrated significant rejection requiring treatment. Two patients with low uptake and an HLR <1.6 had no evidence of rejection either in the simultaneous endomyocardial biopsy or in the endomyocardial biopsy performed the following week. These preliminary results indicate the feasibility of targeting activated lymphocytes with somatostatin receptor imaging in the detection of cardiac allograft rejection. Somatostatin receptor imaging may predict impending rejection at least 1 week before the endomyocardial biopsy becomes positive. The late appearance of diagnostic endomyocardial biopsy probably reflects a lag-time between lymphocytic activation and induction of myocyte damage. Furthermore, somatostatin receptor imaging at 4 h may in any case allow earlier intervention in the event of rejection, given the time required for histological processing of endomyocardial biopsy.  相似文献   
82.
Introduction Whole brain irradiation (WBRT) remains a recommended treatment for patients with brain metastases from malignant melanoma in terms of symptom palliation, especially when extracranial systemic disease is present. Temozolomide (TMZ) has shown efficacy in the treatment of metastatic melanoma. The objective was to evaluate the potential benefit in survival of two different schedules of total dose and fractionation (20 Gy/5 fractions vs 30 Gy/10 fractions) and further TMZ based chemotherapy. Materials and method We have conducted a retrospective study in a group of twenty-one patients (RTOG Recursive Partitioning Analysis class II) of the use of WBRT with 20 Gy/5 fractions (n=11) and 30 Gy/10 fractions (n=10). All patients received further TMZ based chemotherapy administered as a single chemotherapeutic agent or in combination with chemo-immunotherapy. Results Prognostic variables such as: age, Karnofsky performance status, extracranial metastases and number of brain metastases, were analyzed in both groups of treatment without statistically significant differences. The median survival time (MST) for WBRT 20 Gy group was 4 months (CI 95%: range 2–6 months) and for WBRT 30 Gy group was 4 months (CI 95%: range 0–7 months) without statistically significant differences (Log rank p=0.74). There was one complete response and two partial responses. Conclusions The results suggest that MST was not significantly affected by the total dose/fractionation schedule.  相似文献   
83.
The long cylindrical cord covered by a layer of amnion that extends from the umbilicus of the fetus to the fetal surface of the placenta is known as the umbilical cord, or, in older medical textbooks, as funiculis umbilicalis. The two umbilical arteries extend as branches of the internal iliac arteries that emerge from the fetal body at the umbilicus, and run a helical course through the umbilical cord carrying venous blood to the placenta. In most normal placentas, the umbilical arteries anastomose within 2 cm of insertion into the placenta. The fetal umbilical vein emerges from the placenta and carries oxygenated blood to the fetus. The cord vessels are supported by a matrix of myxomatous connective tissue known as Wharton's jelly. The average length of the umbilical cord is approximately 55 cm at term, but extreme variations in length can occur for unknown reasons. The normal umbilical cord is spiralled. On rare occasions, remnants of the omphalomesenteric and allantoic ducts may be found in the term cord. True knots, false knots, cysts, tumors and vascular abnormalities occur occasionally. Early detection is desirable because some of these abnormalities may affect the fetus adversely, and others are associated with fetal malformations and chromosomal anomalies. Complementary use of Doppler scanning two-dimensional ultrasonography and three-dimensional ultrasonography allows the prenatal diagnosis of most cord abnormalities.  相似文献   
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85.
PURPOSE: To determine the outcome of patients with positive margins after lumpectomy for breast cancer and to address the issue of the relationship between local recurrences and distant metastasis in the absence of chemotherapy. METHODS AND MATERIALS: Among 3697 patients with primary breast cancer, we retrospectively analyzed 152 patients who had undergone conservative surgery with axillary dissection, had infiltrating carcinomas with positive margins, were node-negative, and received radiotherapy without chemotherapy. One-third received hormonal therapy. Endpoints were local failure and distant metastasis. Median follow-up was 72 months. RESULTS: Five- and 10-year recurrence-free survival were 0.80 and 0.71 respectively for local recurrences, and 0.85 and 0.73 respectively for metastasis. Infiltrating carcinoma on the margins was associated with early local relapse as opposed to intraductal carcinoma. Local and distant recurrences had similar patterns of yearly-event probabilities. Hazard of relapsing from metastasis was 2.5 times higher after a local recurrence. In the multivariate analysis, negative estrogen receptors (ER-)(p = 0.0012), histologic multifocality (p = 0.0028), and no hormonal therapy (p = 0.017) predicted local relapses, while ER- (p = 0.004) and pathologic grade (p = 0.009) predicted metastasis. Hormonal therapy did not prevent early local recurrences. CONCLUSION: In this population, reexcision is advisable for local purposes and because the data support the hypothesis that local and distant recurrences are tightly connected.  相似文献   
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87.
Abstract: The association of aplasia cutis congenita of the scalp with distal malformations of the limbs is known as Adams-Oliver syndrome. Other reported associations include palatine or auricular malformations, cardiovascular alterations, and spina bifida. Multiple hereditary patterns have been described for this condition, and sporadic cases have also been reported. We report an infant with Adams-Oliver syndrome associated with intracranial calcifications in whom no evidence of intrauterine infection could be demonstrated.  相似文献   
88.
Sulpiride in the perifornical lateral hypothalamus (pfLH) (4, 8 and 16 μg/ 0.5 μl) increased intracranial temperature (Tic). The hyperthermia started immediately after the injection, peaked 30 min later and lasted for more than 90 min. Sulpiride (12 μg) accelerated recovery from hypothermia in anesthetized animals. Forty-five min after sulpiride Tic raised 1.17±0.06°C. After a control injection the raise was only 0.5±0.13°C. Locally applied dopamine (DA) (5, 10 and 20 μg) 5 min before sulpiride (12 μg) attenuated sulpiride hyperthermia. The largest DA dose reduced Tic (−1.21°C) when administered alone. These findings suggest the existence of D2 receptors in the LH involved in thermoregulation. Chances are that D2 receptors in the human LH could be responsible for the neuroleptic malignant syndrome (NMS), and that sulpiride injections in the rat LH could be used as a model for the study of the pathogenesis of this syndrome.  相似文献   
89.
This study was undertaken to assess the influence of age on the early surgical treatment of acute cholecystitis. One hundred consecutive patients who had early operations for acute cholecystitis were divided into two groups according to age. Group 1 consisted of 41 patients who were younger than 60 years of age, and group 2 was made up of 59 patients who were more than 60 years of age. Shock, leukocytosis, hyperglycemia and uremia were more common in those patients in group 2 (p less than 0.05). The over-all diagnostic effectiveness was 94 per cent. The mortality rate was 4.1 per cent (n = 4). There were no significant differences in morbidity and mortality between both groups. In conclusion, advanced age is not a contraindication for early surgical treatment of acute cholecystitis.  相似文献   
90.
The impact that reexposure to anesthetics delivered in 100% oxygen or in synthetic air (21% oxygen/79% nitrogen) has on the secondary humoral immune response to sheep red blood cells was studied. Mice were immunized twice with a 15-day interval and anesthetized immediately after each antigenic challenge with 1.5% halothane or 1.5% isoflurane for 40 min. Halothane in oxygen resulted in increased numbers of IgG-secreting cells (IgG-SC), while halothane in air depressed the response when compared to control mice. In contrast, isoflurane vaporized in oxygen did not affect IgG-SC numbers, while isoflurane given in air lowered the response. Furthermore, neither 100% oxygen, nor the stress of being in an anesthesia chamber breathing synthetic air for 40 min had any immunological effect in non-anesthetized mice.
The inspired oxygen concentration during halothane or isoflurane anesthesia has an effect on the secondary immune response. The effect is different between halothane and isoflurane, possibly due to differences in the extent of their metabolic and pharmacodynamic properties.  相似文献   
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