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141.
BACKGROUND: We evaluated the value of coronary artery calcification (CAC) score in coronary artery disease (CAD) detection in asymptomatic hemodialysis (HD) patients by evaluating the association among CAC score, exercise electrocardiography (EECG), and Thallium-201 dipyridamole scintigraphy. Correlation between aortic pulse wave velocity (PWV) and CAC score was also evaluated. METHODS: CAC score was assessed with conventional computed tomography in 40 patients. Thirty patients completed EECG and 25; those with a positive CAC score and/or a positive EECG performed Thallium dipyridamole scintigraphy. Carotid-femoral PWV was assessed in all patients. RESULTS: There was no association among CAC score and EECG or Thallium dipyridamole scintigraphy. In contrast, CAC score was correlated with aortic PWV. CONCLUSION: The previous results question the role of CAC score in the detection of CAD in asymptomatic HD patients. The correlation between CAC score and aortic PWV raises the possibility that CAC score represents more an indicator of coronary artery medial wall calcification than a marker of CAD.  相似文献   
142.
BACKGROUND: Osteopontin (OPN) is reported to have two distinct functions in kidney disease: Promotion of inflammation at sites of tissue injury, and inhibition of calcium oxalate monohydrate stone formation. However, many of the studies supporting these functions were carried out in animal models of acute renal injury or in cultured cells; thus, the role of OPN in chronic renal disease is not well defined. We examined the role of OPN in adenine phosphoribosyltransferase (Aprt) knockout mice, in which inflammation and formation of 2,8-dihydroxyadenine (DHA) kidney stones are prominent features, by generating Aprt/Opn double knockout mice. METHODS: We characterized the phenotypes of six- and 12-week-old Aprt-/- Opn-/-, Aprt-/- Opn+/+, Aprt+/+ Opn-/-, and Aprt+/+ Opn+/+ male and female mice using biochemical, histologic, immunohistochemical, and in situ hybridization techniques. RESULTS: At 6 weeks of age, there was no difference in phenotype between double knockout and Aprt knockout mice. At 12 weeks, there was increased adenine and DHA excretion, renal crystal deposition, and inflammation in double knockout versus Aprt knockout male mice. Double knockout and Aprt knockout female mice at 12 weeks had less pathology than their male counterparts, but kidneys from double knockout females showed more inflammation compared with Aprt knockout females; both genotypes had similar levels of DHA crystal deposition. CONCLUSION: We conclude that (1) OPN is a major inhibitor of DHA crystal deposition and inflammation in male mice; and (2) OPN is a major modifier of the inflammatory response but not of crystal deposition in female mice. Thus, separate mechanisms appear responsible for the tissue changes seen in DKO males versus females.  相似文献   
143.
Ectopic thyroid tissue in the lower neck with a coexisting normally located multinodular goiter is a rare entity. We present a 27-year old asymptomatic woman with a recent history of a painless mass in the left side of her lower neck. Thyroid function tests were normal. An ultrasound of her neck showed a multinodular goiter and a 3.4 cm solid mass in the left lower cervical area. These findings were confirmed by an MRI scan of her neck. The Tc99m Pertechnetate scan showed the presence of a functioning area under the left lobe of the thyroid gland. The patient underwent surgery. The cervical mass was identified as a structure separate from the left lobe of the thyroid, without any attachments to the body of the gland and was uniformly resected. A subtotal thyroidectomy was also performed. The histology revealed that the separate structure represented ectopic thyroid tissue. The patient had an uneventful postoperative recovery, subsequent to which she was euthyroid and had normal calcium levels.  相似文献   
144.
BACKGROUND: The quality improvement effort in clinical practice has focused mostly on 'performance quality', i.e. on the development of comprehensive, evidence-based guidelines. This study aimed to assess the 'conformance quality', i.e. the extent to which guidelines once developed are correctly and consistently applied. It also aimed to assess the existence of quality gaps in the treatment of certain patient segments as defined by age or gender and to investigate methods to improve overall conformance quality. METHODS: A retrospective audit of clinical practice in a well-defined oncology setting was undertaken and the results compared to those obtained from prospectively applying an internally developed clinical protocol in the same setting and using specific tools to increase conformance quality. RESULTS: All indicators showed improvement after the implementation of the protocol that in many cases reached statistical significance, while in the entire cohort advanced age was associated (although not significantly) with sub-optimal delivery of care. A 'learning curve' phenomenon in the implementation of quality initiatives was detected, with all indicators improving substantially in the second part of the prospective study. CONCLUSIONS: Clinicians should pay separate attention to the implementation of chosen protocols and employ specific tools to increase conformance quality in patient care.  相似文献   
145.
Catastrophic antiphospholipid syndrome in a 14-year-old child   总被引:2,自引:0,他引:2  
Antiphospholipid syndrome (APS) is an autoimmune disease. Less than 1% of patients with APS present with life-threatening catastrophic APS (CAPS). We report here a case of CAPS in a young girl with cardiac, gastrointestinal and renal involvement. Although the management was complicated, the outcome was better than expected. We suggest that CAPS be included in the differential diagnosis of acute renal failure in children with multi-organ involvement and prolonged phospholipid-dependent coagulation time and promptly treated with immunomodulating agents and anticoagulants.  相似文献   
146.
The development of polio vaccines 50 yr ago essentially halted childhood polio epidemics in the industrialized world. During the past quarter century, a constellation of delayed neuromuscular symptoms, called postpolio syndrome, became recognized among the aging polio survivors. The prevalence of postpolio syndrome in the U.S. population is estimated to be in the hundreds of thousands. The most common symptoms are fatigue, pain, and new onset weakness thought to be related to delayed deterioration of motor neuron function. When a patient with postpolio syndrome presents for surgery, special precautions are warranted, because these patients may have respiratory impairment, sleep apnea, swallowing difficulties, and cold intolerance. This article first reviews clinical features and some pathoetiologic theories of postpolio syndrome and then focuses on anesthetic considerations including the use of common anesthetics, neuromuscular blockade, regional anesthesia, and general anesthetic management strategies.  相似文献   
147.
AIM:Model of End-stage Liver Disease (MELD) score has recently gained wide acceptance over the old Child-Pugh score in predicting survival in patients with decompensated cirrhosis, although it is more sophisticated. We compared the predictive values of MELD, Child-Pugh and creatininemodified Child-Pugh scores in decompensated cirrhosis.METHODS: A cohort of 102 patients with decompensated cirrhosis followed-up for a median of 6 mo was studied.Two types of modified Child-Pugh scores estimated by adding 0-4 points to the original score using creatinine levels as a sixth categorical variable were evaluated.RESULTS: The areas under the receiver operating characteristic curves did not differ significantly among the four scores, but none had excellent diagnostic accuracy (areas:0.71-0.79). Child-Pugh score appeared to be the worst, while the accuracy of MELD was almost identical with that of modified Child-Pugh in predicting short-term and slightly better in predi~ng medium-term survival. In Cox regression analysis, all four scores were significantly associated with survival, while MELD and creatinine-modified Child-Pugh scores had better predictive values (c-statistics: 0.73 and 0.69-0.70) than Child-Pugh score (c-statistics: 0.65).Adjustment for gamma-glutamate transpeptidase levels increased the predictive values of all systems (c-statistics:0.77-0.81). Analysis of the expected and observed survival curves in patients subgroups according to their prognosis showed that all models fit the data reasonably well with MELD probably discriminating better the subgroups withworse prognosis.CONCLUSION: MELD compared to the old Child-Pugh and particularly to creatinine-modified Child-Pugh scores does not appear to offer a clear advantage in predicting survival in patients with decompensated cirrhosis in daily clinical practice.  相似文献   
148.
There are two histological types of pyogenic granuloma (PG) of the oral cavity: the lobular capillary hemangioma (LCH) and non-LCH type. The aim of the present study was to examine and compare the clinical features, etiological factors, diameter of vascular elements and immunohistochemical features of LCH and non-LCH histological types of PG to determine whether they are two distinct entities. Thirty cases of LCH and 26 cases of non-LCH PG were retrieved and retrospectively studied. Clinically, LCH PG occurred more frequently (66.4%) as sessile lesion whereas non-LCH PG occurred as pedunculated (77%). Non-LCH PG was associated more frequently (86.4%) with etiological factors. The lobular area of the LCH PG contained a greater number of blood vessels with small luminal diameter than did the central area of non-LCH PG. In the central area of non-LCH PG a significantly greater number of vessels with perivascular mesenchymal cells non-reactive for alpha-smooth muscle actin and muscle-specific actin was present than in the lobular area of LCH PG. The differences found in the present study suggest that the two histological types of PG represent distinct entities.  相似文献   
149.
Microglia motility plays a crucial role in response to lesion or exocytotoxic damage of the cerebral tissue. The neuropeptide neurotensin elicited the migration of the human microglial cell line C13NJ by a mechanism dependent on both phosphatidylinositol-3 kinase (PI3 kinase) and mitogen-activated protein (MAP) kinases pathways. The effect of neurotensin on cell migration was blocked by the neurotensin receptor-3 propeptide, a selective ligand of this receptor. The type I neurotensin receptor-3 was the only known neurotensin receptor expressed in these microglial cells, and its activation led to the phosphorylation of both extracellular signaling-regulated kinases Erk1/2 and Akt. Furthermore, the effect of neurotensin on cell migration was preceded by a profound modification of the F-actin cytoskeleton, particularly by the rapid formation of numerous cell filopodia. Both the motility and the filopodia appearance induced by neurotensin were totally blocked by selective inhibitors of MAP kinases or PI3 kinase pathways. In the murine microglial cell line N11, the neurotensin receptor-3 is also the only neurotensin receptor expressed, and its activation by neurotensin leads to the phosphorylation of both Erk1/2 and Akt. In these cells, neurotensin induces the gene expression of several cytokines/chemokines, including MIP-2, MCP-1, interleukin-1beta and tumor necrosis factor-alpha. This induction is dependent on both protein kinases pathways. We observed that the effect of neurotensin on the cytokine/chemokine expression is also inhibited by the neurotensin receptor-3 propeptide. This is the demonstration that the neurotensin receptor-3 is functional and mediates both the migratory action of neurotensin and its induction of chemokines/cytokines expression.  相似文献   
150.
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