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1.
A 48-year-old smoker with a history of hyperthyroidism treated 10 years prior to presentation with radioactive iodine ablation of the thyroid gland presented to his ophthalmologist with a 2-week history of transient loss of vision in the right eye occurring for 1 to 2 hours each morning. He denied ocular pain, diplopia or change in the prominence of one or both eyes. Examination revealed 2 mm of relative proptosis on the right, bilateral temporal flare and lower lid retraction. There was minimal upper lid retraction and no evidence of lid lag. Ocular motility was full. Dilated fundoscopic examination revealed bilateral optic nerve edema, right more than left. CT of the orbit demonstrated enlargement of the extraocular muscles bilaterally with marked enlargement of the right medial rectus and left inferior rectus muscles resulting in crowding at the orbital apex bilaterally. Laboratory testing revealed the patient to be hyperthyroid. The patient was treated with high dose oral steroids followed by orbital radiation. Hyperthyroidism was managed by the patient’s primary care physician. Visual symptoms rapidly improved with oral steroids and orbital radiation. Optic nerve edema completely resolved. Repeat CT imaging demonstrated a reduction in the enlargement of the extraocular muscles with relief of bilateral optic nerve compression.  相似文献   
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Although renal dysfunction is common after liver transplantation, postoperative renal function after split liver transplantation (SLT) has not been well studied. Renal function immediately after surgery was analyzed retrospectively in 16 patients that received a SLT (SLT group). The results were compared with corresponding data from 31 matched patients that received a full-size liver transplant (FSLT group) during the same period. Serum creatinine (SCr) was measured before surgery, and, after transplantation, daily during the first week and at days 14, 21, and 28. Renal dysfunction (RD) was defined as the requirement for renal replacement therapy (RRT) or a 100% increase in SCr if the basal value had been <1.0 mg/dL or a 50% increase in SCr if the basal value had been >1.0 mg/dL. SCr had to be at least 1.5 mg/dL for a diagnosis of RD to be considered. The classification of RD was: mild, SCr 1.5-2.4 mg/dL; moderate, SCr 2.5-4.0 mg/dL; or severe, SCr >4.0 mg/dL (the requirement for RRT). Both donor and recipient age and cold ischemia time were lower in the SLT group than in the FSLT group (P < 0.05). Length of surgery was longer in the SLT group (P < 0.05). There were no significant differences between groups with respect to Model for End-Stage Liver Disease scores, the need for transfusions, the length of admission to the intensive care unit (ICU), survival rate, individual severity index, or sepsis-related organ failure assessment scores at the time of diagnosing RD. Immunosuppression regimens were similar in both groups. RD developed in 82% of SLT patients, but in only 58% of FSLT patients (P = not significant [NS]). Among SLT patients, RD (23.0% mild, 15.5% moderate, and 61.5% severe) was more severe (P = 0.007) than in FSLT patients (63.1% mild, 15.8% moderate, and 24.1% severe). The requirement for RRT in the SLT group (43.7%) was significantly greater (P < 0.05) than that in the FSLT group (12.9%). This finding may be due to the different incidence of sepsis in the 2 groups (SLT 37.5% vs. FSLT 9.7%; P < 0.05). In conclusion, although the number of patients studied was small, our data suggest a higher incidence of RD and a greater requirement for RRT in patients that receive a split liver graft than in those that receive a full size liver graft.  相似文献   
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We report a case of a prepubertal girl with juvenile primary hypothyroidism presenting as ovarian cysts and precocious puberty. The 7-year-old female was referred to our clinic because of a pelvic/abdominal mass and vaginal bleeding. Besides these findings, on physical examination we noticed the thyroid gland globally increased and the presence of secondary sexual characteristics. Based upon the clinical profile and investigations, the patient was diagnosed with juvenile primary hypothyroidism due to autoimmune thyroiditis. The cysts and precocious puberty resolved spontaneously after the simple replacement of thyroid hormone. It is important to bear in mind hypothyroidism in cases of girls presenting ovarian cysts and precocious puberty in order to avoid unnecessary surgery on the ovaries.  相似文献   
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This paper presents our initial experience utilizing a new technique which allows CT and MR image fusion in patients with skull base lesions. Eleven patients with a variety of skull base lesions underwent CT and MR imaging prior to surgery. Both sets of images were coregistered using customized software. The CT and MR data sets were then combined and viewed in a single interactive image formar using a high-speed graphic computing system. Image fusion allowed simultaneous visualization of the bony skull base anatomy (CT) and detailed soft tissue anatomy (MR) using a single image format. Combining both modalities was felt to provide a better assessment of the extent of lesions and improve understanding of their relationship to adjacent bony and neurovascular anatomy. Specifically, image fusion enhanced awareness of location of skill base lesions with respect to the cavernous sinuses. Gasserian ganglia, carotid arteries, and jugular foramina. For tumors arising within the internal auditory canal (IAC), fused images allowed better delineation of the lateral aspect of the lesion with respect to the fundus of the IAC. Thus, fusion of CT and MR studies provides a unique image format which has advantages over single modality display. We believe image fusion is beneficial for surgical planning and for treatment planning of complex skull base malignancies treated with radiotherapy.  相似文献   
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New inferior vena caval filters for percutaneous placement were made by attaching filter wires similar to those in the bird's nest inferior vena caval filter onto expandable metallic stents. These stents formed a base on which to anchor the filter to the wall of the inferior vena cava. The stent filter can be introduced through a 12- to 13-French catheter sheath system. The system was successfully tested in 13 dogs.  相似文献   
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AIMS: The developing world is particularly at risk of an increasing health burden due to an increased prevalence of Chronic Obstructive Pulmonary Disease (COPD) secondary to increasing tobacco consumption. However, research is scarce. The objectives of this study were to assess the current competence for diagnosing COPD in primary care in a resource-limited setting in Brazil, and to develop a local patient profile for case-finding. METHODS: 34 general practitioners (GPs) in five areas of northern Brazil recruited adult patients with principal complaints of cough and/or shortness of breath who then had spirometry (n = 142). RESULTS: For the dichotomous variable 'COPD' the degree of agreement between GP diagnosis (n = 64, 18.3%) and spirometric outcome (n = 36, 25.4%) was poor, with Kappa = 0.055 (SE 0.087) and DOR = 1.35. False-positive and false-negative diagnosis proportions were 19.8% and 75%, respectively. Independent risk factors were 'smoking history of more than five pack years' and 'presence of both dyspnoea and cough'. It requires the testing of 2.2 smokers with more than five pack years to detect one patient at risk. CONCLUSIONS: COPD is a common yet underdiagnosed disease in Brazilian primary care. Spirometry improves diagnostic competence and case-finding substantially. If applied in a pre-selected high-risk population, we believe spirometry can be a cost-effective diagnostic tool for case-finding in the resource-limited setting. This study provides important baseline information for effective guideline implementation.  相似文献   
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Plasma biotin concentration and lymphocyte propionyl CoA carboxylase (PCC) and its activation index (the ratio of enzyme activity in cells incubated with biotin to activity in cells incubated without the vitamin) were compared as markers of biotin status in patients on biotin-free prolonged total parenteral nutrition (TPN). Five patients had been on biotin-free TPN for over 1 month when the study was started, and had already developed clinical signs that may be caused by this vitamin deficiency. They had markedly reduced levels of both biotin and carboxylase levels, which increased to near normal levels 4 months after biotin was added to the TPN. They initially presented subnormal plasma zinc concentrations which were normal at the end of the study. Another 4 patients also received biotin-free TPN. After 1 month propionyl CoA carboxylase, which was already below normal in 3 of them at admission, further decreased and became undetectable in 1 of them, who presented clinical deficiency manifestations. The enzyme activation index increased more than twice, although plasma biotin remained normal. When the vitamin was added to the TPN solution, PCC activity increased and its activation index decreased to normal. Plasma zinc concentrations remained normal throughout in this other group of patients indicating that changes of biotin markers are not likely to be related to zinc status variation. Plasma biotinidase, a key enzyme in biotin endogenous recycling, was already subnormal at admission and had become normal at the end of the study, but was not associated with the biotin status.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
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The synthesis and evaluation of a new class of diuretic agents derived from the pyrazino[2,3-c][1,2,6]thiadiazine 2,2-dioxide ring system are described. Preliminary structure-activity relationships indicate that the nature and location of the substituents at different positions of the heterocycle are crucial for activity. Thus, a novel synthetic methodology has been developed to selectively introduce the desired substituents at different positions. From the study of the pharmacological properties (dose-response curves, duration of action, and acute toxicity) of the most active compounds, 4-amino-1,7-diethyl-6-methylpyrazino[2,3-c][1,2,6]thiadiazine++ + 2,2-dioxide (9) was selected for further investigation. Compound 9 (C10H15N5O2S) crystallizes in space group P21/a with unit cell dimensions a = 16.482 (1), b = 9.3484 (3), c = 8.333 (3) A, beta = 103.003 (3) degrees, Z = 4.  相似文献   
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