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41.
Trends in cardiovascular complications of diabetes   总被引:2,自引:0,他引:2  
Leibson CL  Narayan KM 《JAMA》2005,293(14):1723-1724
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BACKGROUND: The improvement of regional and global ventricular function following percutaneous coronary intervention (PCI) with reperfusion of the artery supplying the infarct area in acute myocardial infarction is well-described. However, little is known of the potential effects of late recanalization of chronic coronary artery occlusion on left ventricular function. OBJECTIVE: To determine whether PCI improves regional and global left ventricular function in patients with chronic coronary artery occlusions. PATIENTS AND METHODS: Thirty-five patients having at least one coronary artery occluded for six weeks or longer were included in the present prospective study. Exercise thallium-201 myocardial perfusion scintigraphy, multiple-gated acquisition ventriculography and two-dimensional echocardiography were performed in 19 patients (16 men; mean age of 58+/-5 years) who underwent a successful PCI to assess both regional and global left ventricular function before and six weeks following the procedure. RESULTS: The mean ejection fractions before and after reperfusion were 51+/-7% and 58+/-6% using Simpson's method (P<0.001) by echocardiography, and 45+/-1% and 53+/-1% (P=0.01) by multiple-gated acquisition ventriculography, respectively. The echocardiographic wall motion score was 24+/-9 before and 15+/-6 after PCI (P<0.001). The exercise perfusion score (21+/-1 and 14+/-1 [P=0.01]), rest perfusion score (15+/-1 and 12+/-1 [P=0.02]) and reinjection perfusion score (14+/-1 and 11.1+/-1 [P=0.07]) also improved after PCI. The presence of angina was strongly associated with an improvement in left ventricular function and wall motion score (P<0.01). CONCLUSIONS: PCI significantly improved the regional and global left ventricular function in patients with chronic total coronary occlusion. This procedure may provide symptom benefits in selected patients.  相似文献   
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Although port wine stains are seen in 0.3% births, widespread cutaneous capillary malformations are unusual and an association with static gliosis has not been previously reported. This is a report of a 3-year-old boy with a fixed widespread capillary naevus (port wine stain), megalencephaly and global developmental, and features of gliosis on brain magnetic resonance imaging (MRI).  相似文献   
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To assess the outcome of low-dose-ganciclovir prophylaxis (500 mg twice a day for 3 months) in renal-transplant recipients, a retrospective analysis of 185 patients transplanted between 1998 and 2001 was performed. There were 29 (15.6%) patients who belonged to the highest risk group, donor cytomegalovirus (CMV) positive, recipient negative (D + R-), and 37 (20%) patients in the lowest risk group, D-R-. Induction immunosuppression consisted of polyclonal antibody or OKT3 (n = 62, 33.5%), interleukin-2 receptor antibody (n = 61, 33%), and no induction (n = 62, 33.5%). CMV disease occurred in 13 (7%) patients. Highest incidence was in D + R- group (17.2%), with no cases in D-R- group (P = 0.03). Tissue-invasive CMV occurred in 4 of these 13 patients. In patients developing CMV disease, there was no evidence of ganciclovir resistance and no mortality over a mean follow-up of 42 months. Low-dose ganciclovir was found to be as effective in decreasing the incidence of clinical CMV disease as high-dose ganciclovir (1 gm three times a day for 3-6 months) in previous studies.  相似文献   
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String vessels are collagenous structures connected to capillaries. They have no endothelial cells or lumen. We assessed collagen IV-labeled string vessels in the white matter (WM) of subjects with Alzheimer's disease (AD) (n = 12) and non-AD controls (n = 11) using 100 microm celloidin sections. Ten standard fields were digitally captured and the number and length of normal vessels and string vessels were quantified by computerized image analysis. The WM of the AD-diagnosed individuals contained more strings per mm2 (3.95 +/- 0.49) than comparable WM from controls (1.36 +/- 0.39) (p = 0.0005) and had increased total string vessel length in mm/mm2 (AD = 0.29 +/- 0.04; control = 0.10 +/- 0.03; p = 0.0015). There was a 25% increase (not statistically significant) in vessel density in mm/mm2 in AD subjects (AD = 11.88 +/- 0.87; control = 9.53 +/- 0.78; p = 0.06), presumably due to brain atrophy in the white matter. Although vessel length was slightly increased in AD subjects, they still had more than double the string length per total vessel length (AD = 2.88 +/- 0.38) compared to controls (1.36 +/- 0.27) (p = 0.0057). This increase in string vessels in the white matter of AD subjects suggests a decrease in vascular supply in this disease.  相似文献   
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The term mucositis is coined to describe the adverse effects of radiation and chemotherapy treatments. Mucositis is one of the most common adverse reactions encountered in radiation therapy for head and neck cancers, as well as in chemotherapy, in particular with drugs affecting DNA synthesis (S-phase-specific agents such as fluorouracil, methotrexate, and cytarabine). Mucositis may limit the patient's ability to tolerate chemotherapy or radiation therapy, and nutritional status is compromised. It may drastically affect cancer treatment as well as the patient's quality of life. The incidence and severity of mucositis will vary from patient to patient. It will also vary from treatment to treatment. It is estimated that there is 40% incidence of mucositis in patients treated with standard chemotherapy and this will not only increase with the number of treatment cycles but also with previous episodes. Similarly, patients who undergo bone marrow transplantation and who receive high doses of chemotherapy have a 76% chance of getting mucositis. Patients receiving radiation, in particular to head and neck cancers, have a 30% to 60% chance. The exact pathophysiology of development is not known, but it is thought to be divided into direct and indirect mucositis. Chemotherapy and/or radiation therapy will interfere with the normal turnover of epithelial, cells leading to mucosal injury; subsequently, it can also occur due to indirect invasion of Gram-negative bacteria and fungal species because most of the cancer drugs will cause changes in blood counts. With the advancement in cytology, a more precise mechanism has been established. With this understanding, we can select and target particular mediators responsible for the mucositis. Risk factors such as age, nutritional status, type of malignancy, and oral care during treatment will play important roles in the development of mucositis. Many treatment options are available to prevent and treat this condition, but none of them can completely prevent or treat mucositis. More and more pathological methods are being developed to understand this condition so that better therapeutic regimens can be selected. Emphasis also should be made in assessing the patient's psychologic condition, particular depressive disorders. This is important because treatment with antidepressants will not only contribute in lifting depression but also reduces pain somatization. Although mucositis is rarely life-threatening, it will interfere with treatment of cancer to a great extent.  相似文献   
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