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排序方式: 共有1540条查询结果,搜索用时 15 毫秒
91.
Ardissino G Avolio L Dacco V Testa S Marra G Viganò S Loi S Caione P De Castro R De Pascale S Marras E Riccipetitoni G Selvaggio G Pedotti P Claris-Appiani A Ciofani A Dello Strologo L Lama G Montini G Verrina E;ItalKid Project 《The Journal of urology》2004,172(1):305-310
PURPOSE: The nephropathy associated with vesicoureteral reflux (VUR) is one of the leading causes of chronic renal failure (CRF) in children. We describe the clinical course of the disease based on information available in the ItalKid Project database, and analyze the predictive value of baseline renal function, age at VUR diagnosis and urinary protein excretion in relation to the risk of progressive renal failure. MATERIALS AND METHODS: As of December 31, 2001 the registry included a total of 343 patients (261 males) with a diagnosis of primary VUR, which was the leading single cause of CRF, accounting for 25.4% of all patients with CRF. RESULTS: The estimated risk of end stage renal disease (ESRD) by age 20 years was 56%. The patients with a creatinine clearance (Ccr) of less than 40 ml per minute at baseline had an estimated 4-fold greater risk of ESRD developing in comparison with those whose Ccr was 40 to 75 ml per minute. No significant difference in probability of disease progression to ESRD was found between subjects diagnosed with VUR at age 6 months or less and those diagnosed later (older than 6 months). Furthermore, children with normal urinary protein excretion (a urinary protein [uPr]/urinary creatinine [uCr] ratio of less than 0.2 in 36 patients) and low grade proteinuria (uPr/uCr 0.2 to 0.8 in 34 patients) at baseline showed a significantly slower decrease in mean Ccr than those with moderate proteinuria (uPr/uCr greater than 0.8 in 34 patients). Hypertension and/or antihypertensive treatment (including antiprogressive drugs) were reported in 29.1% of patients. CONCLUSIONS: The results of the present study define the long-term risk of ESRD in a large population of children with CRF and VUR, and provide some critical information for identifying the prognosis. 相似文献
92.
Lama G Graziano L Calabrese E Grassia C Rambaldi PF Cioce F Tedesco MA Di Salvo G Esposito-Salsano M 《Pediatric nephrology (Berlin, Germany)》2004,19(4):413-418
We evaluated blood pressure in a sample of patients with neurofibromatosis type 1 (NF1), using ambulatory blood pressure monitoring (ABPM), to determine whether ABPM, when compared with casual BP recordings, allowed the detection of a higher risk for hypertension. We also evaluated the correlation between BP and vascular abnormalities. We studied 69 NF1 patients (36 males and 33 females) with a mean age of 11±4 years, divided into group A, with 24-h mean systolic blood pressure (SBP) or diastolic blood pressure (DBP) <95th percentile, and group B, with mean SBP or DBP >95th percentile. Standard electrocardiography and M-mode, two-dimensional echocardiography were performed and all patients were in sinus rhythm. ABPM identified 11 hypertensive patients (16%); 5 had a mean SBP >95th percentile, 3 mean SBP–DBP >95th percentile, and 3 a mean DBP >95th percentile. Laboratory and other investigations to exclude secondary hypertension were normal. Cardiac abnormalities were found in 13 of the 69 patients (18.8%) with NF1. There were no significant clinical and cardiac differences between the normotensive and hypertensive group. Our data emphasize the importance of periodic ABPM in NF1 patients to diagnose hypertension early and avoid target organ damage and increased mortality. 相似文献
93.
A longitudinal design was used to examine spatial working memory performance in aging Long-Evans rats on a 12-arm, delayed-non-match-to-sample radial maze task. Compared to performance at 12-13 months of age, the same rats exhibited a significant performance deficit at 15-16 months of age across all retention intervals (1.5-10h). All rats exhibited some degree of decline, and no rat performed as well as they had 3 months earlier. This early onset deficit may relate to the degree of difficulty required to perform accurately in a task that maximizes both spatial information processing and flexible working memory representations. Following our observation, rats were implanted with a chronic cannula aimed at the medial septal nucleus. Acute intraseptal tacrine treatments (0.0-25 micrograms/0.5 microl) did not significantly affect any index of performance. Rats exhibited further memory decline over the course of testing (up to 20 months of age). Detection of early onset dysfunction could allow for experimental analysis of underlying mechanisms and therapeutic strategies early in the course of age-related changes. 相似文献
94.
Arce S Luger E Muehlinghaus G Cassese G Hauser A Horst A Lehnert K Odendahl M Hönemann D Heller KD Kleinschmidt H Berek C Dörner T Krenn V Hiepe F Bargou R Radbruch A Manz RA 《Journal of leukocyte biology》2004,75(6):1022-1028
Despite the important role immunoglobulin G (IgG)-secreting plasma cells play in memory immune responses, the differentiation and homeostasis of these cells are not completely understood. Here, we studied the differentiation of human IgG-secreting cells ex vivo and in vitro, identifying these cells by the cellular affinity matrix technology. Several subpopulations of IgG-secreting cells were identified among the cells isolated from tonsils and bone marrow, particularly differing in the expression levels of CD9, CD19, and CD38. CD38 low IgG-secreting cells were present exclusively in the tonsils. A major fraction of these cells appeared to be early plasma cell precursors, as upon activation of B cells in vitro, IgG secretion preceded up-regulation of CD38, and on tonsillar sections, IgG-containing, CD38 low cells with a plasmacytoid phenotype were found in follicles, where plasma cell differentiation starts. A unitary phenotype of migratory peripheral blood IgG-secreting cells suggests that all bone marrow plasma cell populations share a common precursor cell. These data are compatible with a multistep model for plasma cell differentiation and imply that a common CD38 low IgG-secreting precursor gives rise to a diverse plasma cell compartment. 相似文献
95.
Lombardi F Raia V Spagnuolo MI Nugnes R Valerio G Ciccarelli G Franzese A 《Pediatric diabetes》2004,5(4):199-201
Cystic fibrosis (CF)-related diabetes mellitus is an unusual complication in very young pediatric patients with CF. It is generally associated with more severe clinical manifestations of CF. In this report, we describe a case of diabetes and CF starting in infancy. The patient manifested a form of intermittent diabetes without fasting hyperglycemia, which was exacerbated by steroid treatment during pulmonary disease and occasionally required insulin therapy. Insulin responses to oral and intravenous glucose challenge were low. The clinical and radiological status was stable during the 9-yr follow-up. Our patient demonstrates that diabetes may not only represent a complication of CF, as previously maintained, but can also be a co-morbid condition proceeding along with the exocrine disease. The early occurrence of hyperglycemia in this case may highlight an impairment of beta-cell function, which might be genetically determined. Careful monitoring of the glucose profile and of beta-cell function is indicated in patients with CF to avoid late recognition of diabetes. 相似文献
96.
97.
Hemolytic effects of water-soluble fullerene derivatives 总被引:3,自引:0,他引:3
Bosi S Feruglio L Da Ros T Spalluto G Gregoretti B Terdoslavich M Decorti G Passamonti S Moro S Prato M 《Journal of medicinal chemistry》2004,47(27):6711-6715
A series of water-soluble fullerene C(60) derivatives has been investigated for their cytotoxic and hemolytic properties, with the aim to correlate structure with toxicity. We observed that cationic chains induce significant toxicity while the presence of neutral or anionic moieties did not produce any response in our model. A validation of these experimental observations has been performed by theoretical studies in which hydrophilic and hydrophobic surface areas were correlated quantitatively with hemolytic properties. 相似文献
98.
99.
Low prevalence of BRAF mutations in radiation-induced thyroid tumors in contrast to sporadic papillary carcinomas 总被引:10,自引:0,他引:10
Nikiforova MN Ciampi R Salvatore G Santoro M Gandhi M Knauf JA Thomas GA Jeremiah S Bogdanova TI Tronko MD Fagin JA Nikiforov YE 《Cancer letters》2004,209(1):1-6
Point mutations of the BRAF gene have been recently described with high prevalence in papillary thyroid carcinomas. However, this molecular alteration has not been studied in radiation-induced thyroid tumors. We analyzed the prevalence of BRAF point mutations and RET/PTC rearrangements in 55 post-Chernobyl papillary carcinomas, compared with 82 sporadic papillary carcinomas. Radiation-induced tumors demonstrated a low prevalence (4%) of BRAF point mutations and high prevalence (58%) of RET/PTC rearrangements. Sporadic papillary carcinomas revealed a clearly distinct pattern, with 37% of tumors harboring BRAF mutations and 20% RET/PTC rearrangements. These results demonstrate a significant difference in the molecular genetic profile of sporadic and radiation-induced thyroid tumors. 相似文献
100.