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William B. Kannel MD Ramachandran S. Vasan MD 《Current cardiovascular risk reports》2007,1(3):204-208
Low diastolic blood pressure is alleged to impose excess cardiovascular disease (CVD) risk in patients with treated hypertension,
impeding aggressive reduction of blood pressure. Most investigations that assessed the potential J-shaped relations of diastolic
blood pressure and adverse outcomes have not adequately considered systolic or pulse pressure in statistical analyses. An
overview of hypertension trials indicates that lowering elevated blood pressure reduces the risk of CVD outcomes irrespective
of the associated decrease in diastolic pressure, even if the achieved diastolic pressure averages less than 70 mm Hg. The
Framingham study investigations have determined that the increased CVD incidence observed at low diastolic blood pressure
levels is confined largely to persons with concomitantly increased systolic pressure. This finding of no true excess risk
at low diastolic blood pressure agrees with the results of trials that have evaluated the J-curve phenomenon adjusting for
systolic pressure. Aggressively treating systolic hypertension appears to produce no cause for alarm. 相似文献
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Background: The fabrication of dental prosthesis requires the transfer of interocclusal records from patient's mouth to semiadjustable articulators using different kinds of recording media. Any inaccuracy in these interocclusal records leads to occlusal errors in the final prosthesis. This study was conducted to evaluate the dimensional changes occurring in the interocclusal recording material over a given period of time and the material's resistance to compression during the cast mounting on the articulator. 相似文献
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Neuroimaging in Pineal Tumors 总被引:4,自引:0,他引:4
F Reis MD AV Faria MD PhD VA Zanardi MD PhD JR Menezes MD F Cendes MD PhD LS Queiroz MD PhD 《Journal of neuroimaging》2006,16(1):52-58
BACKGROUND AND PURPOSE: The authors report radiological findings in 11 tumors in the pineal region, which were histologically diagnosed as germinomas, pineocytomas pineoblastomas, ependymomas, teratomas, and astrocytomas. METHODS: Computed tomography (CT) was performed in seven patients and magnetic resonance imaging (MRI) was performed in all patients. RESULTS: CT showed a solid or solid/cystic mass with variable contrast enhancement. MRI showed a heterogeneous mass, with hypointense signal on T1 and iso/hyperintense signal on T2-weighted images (WI) and gadolinium enhancement. Extension to adjacent structures occurred in five patients and spread through the cerebral spinal fluid (CSF) in two. CONCLUSIONS: Pineal region tumors have no pathognomonic imaging pattern. MRI and CT are complementary in diagnosis and are important to determine localization, extension, and meningeal spread. 相似文献
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During the first half of the 20th century, chronic energy undernutrition due to low dietary intake, repeated infections, and rapid succession of pregnancy were the factors most responsible for maternal undernutrition and consequent adverse outcomes of pregnancy. Efforts to improve dietary intake, treatment of infections, and provision of contraceptive care were the major focuses of intervention from 1950 to 1990. These interventions resulted in reduction in severe grades of undernutrition. However, there was no reduction in mild and moderate degrees of undernutrition and anemia during pregnancy and there was no significant improvement in the course and outcome of pregnancy, or in birth weight. During the 1990s, among the middle- and upper-income groups, there has been a progressive rise in obesity and consequent adverse effects. The advent of HIV infection in India in the 1980s will inevitably lead to increases in severe undernutrition associated with HIV infection in pregnancy and an adverse impact of maternal HIV infection on the fetus. Practicing physicians and nutritionists in the new millennium will therefore have to assess each person individually and provide appropriate advice regarding diet, exercise, fertility, and infection prevention and control in order to achieve optimum health and nutrition status during pregnancy and to prevent adverse pregnancy outcomes. 相似文献
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Bipolar affective disorder. II. EEG, neuropsychological, and clinical correlates of CT abnormality 总被引:1,自引:0,他引:1
M J Dewan C V Haldipur M F Boucher T Ramachandran L F Major 《Acta psychiatrica Scandinavica》1988,77(6):677-682
Since the clinical significance of CT abnormalities found in bipolar patients remains obscure, we studied 26 DSM-III bipolar patients who had specific CT abnormalities (third ventricle enlargement, and hyperdensity of the caudate, thalamus, anterior frontal white matter, and right temporal lobe) on numerous parameters such as EEG, the Halstead-Reitan Neuropsychological Battery, premorbid personality adjustment, family history of affective disorder, positive and negative symptoms, employment history, and response to lithium carbonate treatment. None of these measures could differentiate between the CT abnormal and CT normal subgroups. The implications of these findings are discussed. 相似文献
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Santosh Isaac Poonnoose Raju P Manjooran John Mathew Pranatartiharan Ramachandran 《Journal of clinical neuroscience》2007,14(3):281-283
We report an unusual case of chronic subdural haematoma (CSH) associated with cerebrospinal fluid (CSF) rhinorrhoea emphasizing the importance of managing both conditions simultaneously. A 59- year-old man presented with watery discharge from the right nostril, of 2 months duration. MRI of the brain showed a CSH in the left fronto-parietal region with significant mass effect. There was an arachnoidocoele with a defect in the planum sphenoidale. He first underwent a burr hole evacuation of the CSH following which the CSF rhinorrhea did not subside, even with bed rest. Transnasal endoscopic closure of the CSF dural fistula was done. On the first post-operative day, he was disoriented and a CT scan showed a recollection of the subdural haematoma that required repeat evacuation. The patient was asymptomatic at discharge. To our knowledge this is the first reported case of CSF rhinorrhoea associated with CSH. Simultaneous closure of the CSF dural fistula at the time of evacuation of a coexisting CSH would be the optimal management. 相似文献
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