高分辨率CT对颞部疾病的检查价值

目的：探讨高分辨率CT（HRCT）对颞部疾病的检查价值。方法：对43例颞部疾病患者行常规CT和高分辨率CT（HRCT）检查所获图像对比分析，并讨论HRCT的检查技术和图像后处理。结果：HRCT对病变的显示率及病变引起骨质破坏的程度，病变边缘，轮廓的显示均明显优于常规CT，尤其能清楚显示常规CT难以显示的中耳及内耳的细微结构，结论：高分辨率CT是颞部疾病的首选检查方法，使用高分辨率CT对颞部疾病的检查给临床提供更多，更准确的诊断信息。     

骨巨细胞瘤的MRI诊断价值

目的探讨骨巨细胞瘤的MRI表现特点及其病理基础。资料与方法搜集经手术病理证实的12例骨巨细胞瘤患者资料，分析其MRI征象并与病理结果对照。结果T1WI上肿瘤实体表现为低、等信号，T2WI上为不均匀高信号，Gd-DTPA增强扫描呈中度到明显强化。此外，MRI还可显示肿瘤内坏死、出血、含铁血黄素沉着等。结论MRI能够提供比较全面的影像学信息，可提高对骨巨细胞瘤诊断的准确性。     

Malignant hypertension in general practice

A diagnosis of malignant hypertension was recorded for 165 patients in the national morbidity study between 1970 and 1973. Three patients with benign hypertension were selected as age- and sex-matched controls for each case. The general practitioners in the study were asked to complete a further questionnaire about the patients and 66% of the practices agreed to take part. Information about the retinal findings for the patients was requested and less than half of those in the national morbidity study proved to have a strict diagnosis of accelerated or malignant hypertension although they were originally recorded as patients with malignant hypertension. Of those patients originally classified as having benign hypertension 5% had the retinal appearance of accelerated or malignant hypertension.Patients had been diagnosed as having hypertension for a mean of more than five years prior to entry into the national morbidity study and the survival of patients with both benign and accelerated or malignant hypertension was good. Thirtyfour per cent of those with confirmed benign hypertension and 62% of those with definite accelerated or malignant hypertension died in the follow-up period which was on average 10 years from entry into the national morbidity study.The survival of patients registered with doctors who did not collaborate and of patients whose clinical details were missing was similar to the survival of patients for whom full details were provided.Blood pressure control was only fair with a mean of 172/101 mmHg for the group with benign hypertension and 177/107 mmHg for the group with accelerated or malignant hypertension. Blood pressure control was the poorest for those who died from a stroke. A high proportion (78%) of deaths in association with accelerated or malignant hypertension were from cardiovascular or renal causes.     

Novel proteins with binding specificity for DNA CTG repeats and RNA CUG repeats: implications for myotonic dystrophy

While an unstable CTG triplet repeat expansion is responsible for myotonic dystrophy, the mechanism whereby this genetic defect induces the disease remains unknown. To detect proteins binding to CTG triplet repeats, we performed bandshift analysis using as probes double- stranded DNA fragments having CTG repeats [ds(CTG)6-10] and single- stranded oligonucleotides having CTG repeats ss(CTG)8 or RNA CUG triplet repeats (CUG)8. The source of protein was nuclear and cytoplasmic extracts of HeLa cells, fibroblasts and myotubes. Proteins binding to the double-stranded DNA repeat [ds(CTG)6-10], were inhibited by nonlabeled ds(CTG)6-10, but not by a non-specific DNA fragment (USF/AD-ML). Another protein binding to ssCTG probe and RNA CUG probe was inhibited by nonlabeled (CTG)8 and (CUG)8. Nonlabeled oligos with different triplet repeat sequences, ss(CAG)8 or ss(CGG)8, did not inhibit binding to the ss(CTG)8 probe. However, when labeled as probes, the (CAG)8 and (CGG)8 bound to proteins distinct from the CTG proteins and binding was inhibited by nonlabeled (CAG)8 or (CGG)8 respectively. The protein binding only to the RNA repeat (CUG)8 was inhibited by nonlabeled (CUG)8 but not by nonlabeled single- or double-stranded CTG repeats. Furthermore, the CUG-BP exhibited no binding to an RNA oligonucleotide of triplet repeats of the same length but having a different sequence, CGG. The CUG binding protein was localized to the cytoplasm, whereas dsDNA binding proteins were localized to the nuclear extract. Thus, several trinucleotide binding proteins exist and their specificity is determined by the triplet sequence. The novel protein, CUG-BP, is particularly interesting since it binds to triplet repeats known to be present in myotonin protein kinase mRNA which is responsible for myotonic dystrophy.      

Duke Surgery Research Central: an open-source Web application for the improvement of compliance with research regulation

Background  

Although regulatory compliance in academic research is enforced by law to ensure high quality and safety to participants, its implementation is frequently hindered by cost and logistical barriers. In order to decrease these barriers, we have developed a Web-based application, Duke Surgery Research Central (DSRC), to monitor and streamline the regulatory research process.     

Local histamine release after immunological and non-immunological mast cell degranulationin vivo

Plasma histamine concentration in the circulation has been proposed as an index of mast cell degranulation occurringin vivo but there are problems with this approach in practice. Local elevations in plasma histamine occur in blood draining the site of antigen challenge in forearm skin. We have compared changes in plasma histamine concentration with time following intradermal injection of antigen, codeine or histamine to produce matched wheal and flare responses in 4 atopic subjects. Less histamine appears to be released after non-immunological challenge.     

Plasma histamine concentration during propranolol induced bronchoconstriction.

The mechanism of propranolol induced bronchoconstriction in asthma is uncertain, as airway beta adrenoceptors are not innervated by sympathetic nerves and circulating adrenaline concentrations are not raised. Propranolol 10 mg was infused over 27 minutes in 14 subjects with mild asthma. Peak expiratory flow (PEF) decreased by 80-235 l/min (17-51% of baseline) in nine subjects, who were called "responders," and by less than 50 l/min (12% of baseline) in five "non-responders". These two groups did not differ in baseline ventilatory function or in any clinical characteristic. In "responders" mean PEF had decreased significantly from 440 to 390 l/min after infusion of propranolol 2.1 mg, though the maximum fall in PEF occurred during or within five minutes of the end of the infusion. In nine of the subjects (six "responders" and three "non-responders") the possibility that propranolol induced bronchoconstriction is due to blockade of mast cell beta receptors leading to increased mediator release was examined by measurement of plasma histamine concentration as an index of mast cell degranulation. There was no consistent change in plasma histamine concentration in either group. No evidence of increased mast cell mediator release has been found in association with propranolol induced bronchoconstriction.     

Diagnosis of metastatic lesions to the stomach by salvage cytology

Summary Secondary neoplasms of the stomach are rare and are often clinical and diagnostic problems. Three patients with bleeding volcano-like ulcers were diagnosed by combined endoscopic salvage cytology and surgical biopsy as having metastatic submucosal lesions from hematologic spread. The combination of endoscopic appearance, clinical findings, and tissue and cytologic examination can lead to the correct diagnosis. The results from these cases support the utility of this cytologic technique in combination with biopsy in this clinical setting.     

Contribution of environmental factors to variability in human drug metabolism.

Drug metabolism in 96 London factory and office workers has been studied after simultaneous single doses of antipyrine (phenazone) and paracetamol (acetaminophen). Metabolic clearance of both drugs was significantly greater in subjects eating meat more than once a week than in those who ate meat less frequently. The precise contribution of diet could not be clearly defined since 90% of "meat-eaters" were European while all except one of the "vegetarians" were Asian. Clearance of both drugs increased with both alcohol and cigarette consumption. Regular intake of coffee and/or tea had a similar effect but, in the case of paracetamol, this did not attain statistical significance. Antipyrine clearance was lower among women who took the oral contraceptive pill than among those who did not, while paracetamol clearance was not significantly different. These findings may have implications for the use of drugs which are administered regularly in order to achieve steady-state plasma and tissue concentrations.