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11.
Rao VM; Dalinka MK; Mitchell DG; Spritzer CE; Kaplan F; August CS; Axel L; Kressel HY 《Radiology》1986,161(1):217-220
Four patients with proved osteopetrosis (three with the infantile malignant form and one with the benign form) were examined with magnetic resonance imaging at 1.5 T. All patients were studied in the coronal and sagittal planes using both short and long repetition time/echo time sequences. The infantile malignant form was characterized by a complete lack of signal from the marrow alternating with a signal intensity equivalent to that of the intervertebral disks, resulting in a "stepladder" appearance. In the benign form or after successful marrow transplantation in the infantile malignant form, intermediate or high signal intensity in the vertebrae was noted, suggesting the presence of some marrow elements. 相似文献
12.
Evaluation of plasma cystatin C as a marker for glomerular filtration rate in patients with type 2 diabetes 总被引:17,自引:0,他引:17
Harmoinen AP Kouri TT Wirta OR Lehtimäki TJ Rantalaiho V Turjanmaa VM Pasternack AI 《Clinical nephrology》1999,52(6):363-370
AIM: To evaluate plasma cystatin C as a marker of the glomerular filtration rate in patients with type 2 diabetes and their age and sex-matched controls. MATERIALS AND METHODS: Forty-seven patients with one decade of type 2 diabetes and 51 non-diabetic control subjects were studied. Plasma cystatin C was measured by particle-enhanced turbidimetric immunoassay in a new application for the Hitachi 704 analyzer. For comparison, plasma creatinine and creatinine clearance were measured. The plasma clearance of 51Cr-EDTA by the single injection method was utilized as reference. RESULTS: In patients with type 2 diabetes the correlation coefficient between plasma cystatin C and the plasma clearance of 51Cr-EDTA was 0.774 (Spearman's coefficient) and that between plasma creatinine and the plasma clearance of 51Cr-EDTA was 0.556 (p = 0.001 for the difference). The correlation between creatinine clearance and the plasma clearance of 51Cr-EDTA was 0.411. In receiver operating characteristic (ROC) curve analysis the diagnostic accuracy of plasma cystatin C was significantly better than that of plasma creatinine (p = 0.047) or creatinine clearance (p = 0.001). The best diagnostic efficiency (98%) for cystatin C was obtained when the cut-off limit was set at 1.32 mg/l. In the control group the correlation coefficients were: between cystatin C and the plasma clearance of 51Cr-EDTA 0.627, between creatinine and the plasma clearance of 51Cr-EDTA 0.466 and between creatinine clearance and the plasma clearance of 51Cr-EDTA 0.416. The area under the ROC plot curve of cystatin C was also greatest in the control group, but the diagnostic accuracy of cystatin C was marginally better than that of either plasma creatinine (p = 0.05) or creatinine clearance (p = 0.08). Among the control subjects various non-renal causes may have interfered with cystatin C concentrations reducing the correlations. CONCLUSIONS: Cystatin C measurement is a more sensitive and specific test for GFR in patients with type 2 diabetes than plasma creatinine or its clearance, when GFR is normal or only slightly reduced. If an elevated cystatin C concentration is found, non-renal factors have to be excluded. The turbidimetric application described here can easily be applied for most clinical chemistry analyzers and is therefore useful in daily clinical practice. 相似文献
13.
K. Kaukinen K. Turjanmaa M. Mäki J. Partanen R. Venäläinen T. Reunala P. Collin 《Scandinavian journal of gastroenterology》2013,48(9):942-946
Background: While dyspeptic patients in primary care often receive empirical treatment with antisecretory drugs, a substantial number suffer from motility disturbances which may be associated with their complaints. We aimed to compare the effectiveness of treatment with antisecretory treatment with a prokinetic agent in uninvestigated dyspepsia. Methods: 563 patients presenting dyspeptic complaints to the general practitioner with a low likelihood of organic (ulcer, reflux or malignant) disease, i.e. absence of alarm symptoms or a history of peptic ulcer disease or gastro-oesophageal reflux disease were included. They entered a randomized, double-blind trial of 4 weeks of ranitidine 150 mg bid compared with 4 weeks of cisapride 10 mg bid, with 3 months follow-up. Treatment failure was defined as no response to treatment or a relapse of symptoms within the follow-up period. Also studied were the effect on dyspepsia severity, response to treatment after 4 weeks, and time to relapse. Results: For all randomized patients, the incidence of overall treatment success after 3 months follow-up with antisecretory treatment was 107/271 (39.5%) and with a prokinetic agent 122/282 (43.3%); the risk difference was 3.8% (95% CI-4.4% to 12.0%); the difference in symptom severity score after 4 weeks of treatment was 0.3; 95% CI-0.4% to 1.0%. For patients responding to 4 weeks of treatment, relapsefree time was 86 days in the prokinetic group and 79 days in the acid suppression group (P = 0.005). Conclusions: Antisecretory and prokinetic therapies are equally effective in primary care patients with uninvestigated dyspeptic complaints, though relapse rates are lower in patients treated with prokinetic treatment. 相似文献
14.
Virtanen MP Nieminen T Kähönen MA Majahalme SK Tuomisto MT Turjanmaa VM Kööbi T 《Journal of human hypertension》2008,22(2):126-128
We evaluated the relationship between the variability in the left ventricular mass index (LVMI) and different hemodynamic factors. LVMI was associated with blood pressure and, in one subgroup, strongly to arterial pulse wave velocity (PWV). High physical activity was connected to increased LVMI, and a combination of low stroke index (SI) and high heart rate (HR) to decreased LVMI. 相似文献
15.
Patrick Smith Ph.D. Martti T. Tuomisto Ph.D. James Blumenthal Ph.D. Andrew Sherwood Ph.D. Lauri Parkkinen MS Mika Kähönen MD Ilkka Pörsti MD Silja Majahalme MD Väinö Turjanmaa MD 《Annals of behavioral medicine》2013,45(1):99-109
Background
Psychosocial factors have been associated with cardiovascular outcomes, but few studies have examined the association between psychosocial function and natriuretic peptides.Purpose
The purpose of this study is to determine the predictive value of hostility, anger, and social support in relation to atrial natriuretic peptide (ANP), a marker of vascular health, among middle-aged men.Methods
One hundred twenty-one men (mean age?=?39.8 years, SD?=?4.1) underwent assessments of ANP and completed the Cook–Medley Hostility Scale, the Spielberger State–Trait Anger Scale, and the Interview Schedule for Social Interaction.Results
Higher levels of hostility (β?=?0.22 [95 % CI 0.04, 0.40], P?=?0.032) and trait anger (β?=?0.18 [95 % CI 0.01, 0.37], P?=?0.044) were associated with greater ANP levels. In contrast, higher perceived social support was also associated with lower ANP levels, (β?=??0.19 [95 % CI ?0.05, ?0.41], P?=?0.010).Conclusions
Psychosocial factors, including hostility, anger, and social support, are associated with varying ANP levels among middle-aged men, independent of cardiovascular and behavioral risk factors. 相似文献16.
The activation of factor XI initiates the intrinsic coagulation pathway. Until recently it was believed that the main activator of factor XI is factor XIIa in conjunction with the cofactor high molecular weight kininogen on a negatively charged surface. Two recent reports have presented evidence that in a purified system factor XI is activatable by thrombin together with the soluble polyanion dextran sulfate. To assess the physiological relevance of these findings we studied the activation of factor XI in normal and factor XII-deficient plasma. We used either kaolin/cephalin or dextran sulfate as a surface for the intrinsic coagulation pathway, tissue factor to generate thrombin via the extrinsic pathway, or the addition of alpha-thrombin directly. 125I-factor XI, added to factor XI-deficient plasma at physiologic concentrations (35 nmol/L), is rapidly cleaved on incubation with kaolin. The kinetics appear to be exponential with half the maximum cleavage at 5 minutes. Similar kinetics of factor XI cleavage are seen when 40 nmol/L factor XIIa (equal to 10% of factor XII activation) is added to factor XII-deficient plasma if an activating surface is provided. Tissue factor (1:500) added to plasma did not induce cleavage of factor XI during a 90-minute incubation, although fibrin formation within 30 seconds indicated that thrombin was generated via the extrinsic pathway. Adding 1 mumol/L alpha-thrombin (equivalent to 50% prothrombin activation) directly to factor XII deficient or normal plasma (with or without kaolin/cephalin/Ca2+ or dextran sulfate) led to instantaneous fibrinogen cleavage, but again no cleavage of factor XI was observable. We conclude that in plasma surroundings factor XI is not activated by thrombin, and that proposals of thrombin initiation of the intrinsic coagulation cascade are not supportable. 相似文献
17.
Barbano R ;Palumbo O ;PascuUi B ;Galasso M ;Volinia S ;D'Angelo V ;Icolaro N ;Coco M ;Dimitri L ;Graziano p ;Copetti M ;Valori VM ;Maiello E ;CareUa M ;Fazio VM ;Parrella p 《中华神经外科疾病研究杂志》2014,(5):433-433
Gliomas represent a disparate group of tumours for which there are to date no cure. Thus, there is a recognized need for new diagnostic and therapeutic approaches based on increased understanding of their molecular nature. We performed the comparison of the microRNA (miRNA) profile of 8 WHO grade II gliomas and 24 higher grade tumours (2 WHO grade III and 22 glioblastomas) by using the Affymetrix GeneChip miRNA Array v. 1.0. A relative quantification method (RT-qPCR) with standard curve was used to confirm the 22 miRNA signature resulted by array analysis. The prognostic performances of the confirmed miRNAs were estimated on the Tumor Cancer Genome Atlas (TCGA) datasets. We identified 22 miRNAs distinguishing grade II gliomas from higher grade tumours. RT-qPCR confirmed the differential expression in the two patients'groups for 13 out of the 22 miRNAs. The analysis of the Glioblastoma Multiforme (GBM) and Lower Grade Glioma (LGG) datasets from TCGA demonstrated the association with prognosis for 6 of those miRNAs. Moreover, in the GBM dataset miR-21 and miR-210 were predictors of worse prognosis in both univariable and multivariable Cox regression analyses ( HR 1.19, P = O. 04, and HR 1.18, P = 0. 029 respectively). Our results support a direct contribution of miRNAs to glioma cancerogenesis and suggest that miR-21 and miR-210 may play a role in the aggressive clinical behaviour of glioblastomas. 相似文献
18.
KH Neppelenbroek RS Seó VM Urban S Silva LN Dovigo JH Jorge NH Campanha 《Oral diseases》2014,20(4):329-344
In healthy individuals, Candida species are considered commensal yeasts of the oral cavity. However, these microorganisms can also act as opportunist pathogens, particularly the so‐called non‐albicans Candida species that are increasingly recognized as important agents of human infection. Several surveys have documented increased rates of C. glabrata, C. tropicalis, C. guilliermondii, C. dubliniensis, C. parapsilosis, and C. krusei in local and systemic fungal infections. Some of these species are resistant to antifungal agents. Consequently, rapid and correct identification of species can play an important role in the management of candidiasis. Conventional methods for identification of Candida species are based on morphological and physiological attributes. However, accurate identification of all isolates from clinical samples is often complex and time‐consuming. Hence, several manual and automated rapid commercial systems for identifying these organisms have been developed, some of which may have significant sensitivity issues. To overcome these limitations, newer molecular typing techniques have been developed that allow accurate and rapid identification of Candida species. This study reviewed the current state of identification methods for yeasts, particularly Candida species. 相似文献
19.
Resistance of Copenhagen rats to chemical induction of glutathione S- transferase 7-7-positive liver foci 总被引:2,自引:0,他引:2
Copenhagen (Cop) rats are completely resistant to the chemical induction of
mammary adenocarcinomas, but their susceptibility to hepatocarcinogenesis
is virtually unknown. Rat liver is a well- characterized and easily
manipulated tissue in which to study carcinogenesis. Therefore, if Cop rats
are resistant to hepatocarcinogenesis, studies into resistance mechanisms
may be feasible. Male Cop and F344 rats, 7-8 weeks old, were initiated
using either N-nitrosodiethylamine (DEN) (200 mg/kg, i.p.) or a two-thirds
partial hepatectomy (PH) followed by N-methyl-N-nitrosourea (MNU) (60
mg/kg, i.p.). The rats were then promoted using a modified resistant
hepatocyte (RH) protocol (a combination of four doses of 2-
acetylaminofluorene (2-AAF) and a single dose of CCl4 that provides a
selective mitotic stimulus for initiated cells). Six weeks after initiation
the rats were killed and liver sections were stained for glutathione
S-transferase 7-7 (GST 7-7), a marker for putative preneoplastic
hepatocytes. Cop rats were found to be highly resistant, having a
approximately 9- and approximately 27-fold smaller percentage of liver area
occupied by GST 7-7-positive foci than susceptible F344 rats following
initiation by DEN and MNU respectively. Furthermore, gross liver nodules
did not form in any of the Cop rats, whereas all F344 rat livers contained
nodules. Hepatic necrosis caused by DEN during initiation, and CCl4 during
promotion is necessary to stimulate compensatory hepatocyte division. We
demonstrated that these agents do indeed increase serum transaminase levels
and produce histologic evidence of necrosis in Cop rats. In order for liver
foci to grow rapidly in the RH protocol, the surrounding normal hepatocytes
must be mito-inhibited by 2-AAF. We found that the degree of
mito-inhibition of normal hepatocytes by 2-AAF is the same in Cop and F344
rats. These results show that the Cop rat is highly resistant to the
chemical induction of putative preneoplastic liver foci and nodules.
相似文献
20.
A George VM Srivastava GD Sundararaj 《Journal of Medical Imaging and Radiation Oncology》1997,41(2):199-200
A young man presented with desmoplastic fibroma in the proximal ulna. This rare tumour was treated by curettage and bone grafting. 相似文献