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排序方式: 共有632条查询结果,搜索用时 15 毫秒
81.
We present a rare case of primary spleen Echinococcus cyst with rupture evidence due to trauma. The cyst presented with an echogenic pattern at ultrasound examination but subsequent CT study revealed calcification of the cyst wall and signs of rupture. Serological tests were positive for echinococcus and eosinophilia defined. Volume changes of hydatid cyst were not discernible in the imaging studies despite evidence of rupture. Both imaging methods may suggest the diagnosis unless typical diagnostic features are present. Hydatid disease was confirmed histologically on the specimen after surgical excision of the cyst.  相似文献   
82.
Q fever is a zoonotic disease caused by Coxiella burnetii-an obligate, Gram-negative, intracellular bacteria. Acute febrile illness, hepatitis, and atypical pneumonia are the three most common manifestations, whereas lobar pneumonia is rarely reported among acute Q fever patients. We report a case of acute Q fever with lobar pneumonia and multi-organ involvement.  相似文献   
83.
Breast cancers are the most common cancer-affecting women; critically the identification of novel biomarkers for improving early detection, stratification and differentiation from benign tumours is important for the reduction of morbidity and mortality.To identify and functionally characterise potential biomarkers, we used mass spectrometry (MS) to analyse serum samples representing control, benign breast disease (BBD) and invasive breast cancer (IDC) patients. Complementary and multidimensional proteomic approaches were used to identify and validate novel serum markers.Annexin A3 (ANX A3) was found to be differentially expressed amongst different breast pathologies. The diagnostic value of serum ANX A3 was subsequently validated by ELISA in an independent serum set representing the three groups. Here, ANX A3 was significantly upregulated in the benign disease group sera compared with other groups (P < 0.0005).In addition, paired breast tissue immunostaining confirmed that ANX A3 was abundantly expressed in benign and to a lesser extent malignant neoplastic epithelium. Finally, we illustrated ANX A3 expression in cell culture lysates and conditioned media from neoplastic breast cell lines, and its role in neoplastic breast cell migration in vitro.This study confirms the novel role of ANX A3 as a mammary biomarker, regulator and therapeutic target.  相似文献   
84.

Objectives

To characterize the microstructure, mechanical properties, ionic release and tarnish resistance of conventional and experimental Ag-based soldering alloys for orthodontic applications.

Methods

Disk shaped specimens were prepared from four commercial Ag based soldering alloys [Dentaurum Universal Silver Solder (DEN), Orthodontic Solders (LEO), Ortho Dental Universal Solder (NOB), and Silver Solder (ORT)] and four experimental alloys Ag12Ga, Ag10Ga5Sn, Ag20In and Ag7Sn. The elemental composition and microstructure was determined by SEM/EDX and XRD analysis, while the mechanical properties were determined by Instrumented Indentation Testing. Ionic release of Ag, Cu, Zn, Ga, In and Sn was determined by ICP-EAS in 0.9% NaCl and Ringer’s solutions after 28, 49 and 70 days. Tarnish resistance was also tested and colorimetry was applied to quantify the differences in color (DE) before and after immersion in testing media. DSC was used to determine the melting range of the experimental alloys. Mechanical properties, ionic release and DE were statistically compared by ANOVA and Holm-Sidak multiple comparison test (a = 0.05).

Results

All commercially alloys belong to the Ag–Zn–Cu ternary system and consist a Ag rich face centered cubic (FCC) and Cu (FCC) phase. The former is the predominant phase also in experimental alloys. Conventional alloys demonstrated higherhardness, less ductility and lower melting rangers compared to experimental alloys. Immersion testing revealed the release of Cu and Zn ions from the commercially alloys and Ga ions from AgGa and AgGaSn while no ionic release was identified for AgIn and AgSn. All alloys failed tarnish testing according to ISO 10271 showing DE values much higher than the clinical acceptable limit (3.7).

Significance

The conventional Ag based soldering alloys showed substantial differences in their microstructure, mechanical properties and ionic release, and thus different clinical performance is anticipated. Ga, Sn and In might be employed as alloying addition to modify the properties of Ag brazing alloys.  相似文献   
85.
Objectives:The aim of this research was to assess galvanic behavior of lingual orthodontic brackets coupled with representative types of orthodontic wires.Materials and Methods:Three types of lingual brackets: Incognito (INC), In-Ovation L (IOV), and STb (STB) were combined with a stainless steel (SS) and a nickel-titanium (NiTi) orthodontic archwire. All materials were initially investigated by scanning electron microscopy / x-ray energy dispersive spectroscopy (SEM/EDX) while wires were also tested by x-ray diffraction spectroscopy (XRD). All bracket-wire combinations were immersed in acidic 0.1M NaCl 0.1M lactic acid and neutral NaF 0.3% (wt) electrolyte, and the potential differences were continuously recorded for 48 hours.Results:The SEM/EDX analysis revealed that INC is a single-unit bracket made of a high gold (Au) alloy while IOV and STB are two-piece appliances in which the base and wing are made of SS alloys. The SS wire demonstrated austenite and martensite iron phase, while NiTi wire illustrated an intense austenite crystallographic structure with limited martensite. All bracket wire combinations showed potential differences below the threshold of galvanic corrosion (200 mV) except for INC and STB coupled with NiTi wire in NaF media.Conclusions:The electrochemical results indicate that all brackets tested demonstrated galvanic compatibility with SS wire, but fluoride treatment should be used cautiously with NiTi wires coupled with Au and SS brackets.  相似文献   
86.
The complications of foot ulcerations are the leading cause of hospitalization and amputation among diabetic patients. Yet despite the high associated morbidity and mortality, there is no universally accepted classification system for diabetic foot ulcers. Although a handful of classification systems have been developed, they are used infrequently, even by wound specialists. Only by improving communication between care providers will the healthcare strategies we use be improved, because management of the diabetic foot involves a multidisciplinary approach. This review is meant to provide an overview of four existing classification systems and offer a new system of classification that is simple to conduct, easy to remember, and serves as a guide for treatment. It is our hope that this effort will encourage discussion and debate in the process.  相似文献   
87.
Reports on the success of permanent vascular access in elderly HD patients vary considerably. We reviewed the records of 149 patients [62F and 87M] aged 20–89 years old (median 59) who were on hemodialysis for 6–242 (49 median) months, and had undergone 202 vascular access procedures (177 Cimmino-Brescia fistulae and 25 PTFE grafts). Patients were divided into two groups according to the age they started HD. Group A: 48 patients, over 60 years old (range 60–83; median 70) on HD for 43.5, (6–140) months. Group B: 101 patients, under 60 years old, range (15–59) median 46, on HD for 54 (6–242) months. There were no differences between the two groups in terms of gender, primary renal disease, (except polycystic kidney disease), Hct and EPO administration. The initial choice of vascular access, the complications and the technique survival were examined in both groups. Cimmino-Brescia fistulae were used as the first choice of vascular access in all patients except one in group B. PTFE-grafts were the second or third choice in 7/48 (group A) and 15/101 (group B) (p: NS). The only reason for technique failure was vascular thrombosis in both groups (11/48 group A and 31/101 group B p: NS). Other complications were: aneurysms (10/48 and 14/101, p: NS), infections (0/48 and 2/101 p: NS) and edema (0/48 and 6/101, p: NS). Five-year technique survival of the first AV fistula in the two groups was 35% and 45% respectively (log-rank test, p: NS). These findings suggest that: a) A.V. fistula is the first choice of vascular access in aged HD patients; b) There is no difference in vascular access complications across age groups; c) Survival of the first A.V. fistula is independent of age.  相似文献   
88.
OBJECTIVES: The aim of the present study was to investigate the composition, morphology, bulk structure and ionic release of two brands of titanium orthodontic brackets: Orthos2 (Ormco, USA) and Rematitan (Dentaurum, Germany). METHODS: Five specimens of each group were examined with computerized X-ray microtomography, to reveal the morphology and structure of brackets, whilst resin-embedded and metallographically polished specimens were subjected to SEM/EDS analysis and Vickers microhardness measurements. Brackets were also maintained in 0.9% saline for 2 months and the ionic release in the immersion medium was determined with Inductively Coupled Plasma Atomic Emission Spectroscopy. The results of the hardness and ionic release measurements were statistically analyzed with two-way ANOVA and Tukey's test (alpha = 0.05). RESULTS: Orthos2 brackets consisted of two parts, the base (commercially pure Ti grade II) and the wing (Ti-6Al-4V alloy), joined together by laser welding, producing large gaps along the base-wing interface. The base was of lower hardness (Hv = 145), than the wing (Hv = 392) and incorporated a standard foil base-mesh pad. Rematitan brackets consisted of commercially pure Ti grade IV, with a single-piece manufacturing pattern of virtually identical hardness (p > 0.05) at the base and wings, featuring a laser-etched base-mesh pad. The hardness of the Rematitan brackets was significantly lower than the hardness of the Orthos2 wings, but double the hardness of the Orthos2 base. Released Ti levels were below the threshold level (1 ng/ml) of analysis for both materials, whilst traces of Al (3 ppm) and V (2 ppm) were found in the immersion media for Ti-6Al-4V alloy. SIGNIFICANCE: The structural and hardness differences found may influence the torque transfer characteristics from activated archwires to the brackets and the crevice corrosion potential at the base-wing interface (Orthos2). The detection of Al and V in the immersion medium (Orthos2) may imply a different biological response from the two types of Ti brackets.  相似文献   
89.
90.
Mally A  Walker CL  Everitt JI  Dekant W  Vamvakas S 《Toxicology》2006,224(1-2):108-118
Trichloroethene (TCE) is classified as a potential human carcinogen although there is a significant debate regarding the mechanism of TCE induced renal tumor formation. This controversy stems in part from the extremely high doses of TCE required to induce renal tumors and the potential contribution of the associated nephrotoxicity to tumorigenesis. We have used Eker rats, which are uniquely susceptible to renal carcinogens, to determine if exposures to TCE in vivo or exposure to its metabolite S-(dichlorovinyl)-L-cysteine (DCVC) in vitro can transform kidney epithelial cells in the absence of cytotoxicity. Treatment with TCE (0, 100, 250, 500, 1000 mg/kg bw by gavage, 5 days a week) for 13 weeks resulted in a significant increase in cell proliferation in kidney tubule cells, but did not enhance formation of preneoplastic lesions or tumor incidence in Eker rat kidneys as compared to controls. In vitro, concentrations of DCVC, which reduced cell survival to 50%, were able to transform rat kidney epithelial cells. However, no carcinogen-specific mutations were identified in the VHL or Tsc-2 tumor suppressor genes in the transformants. Taken together, the inability of TCE to enhance formation of preneoplastic changes or neoplasia and the absence of carcinogen-specific alteration of genes accepted to be critical for renal tumor development suggest that TCE mediated carcinogenicity may occur secondary to continuous toxic injury and sustained regenerative cell proliferation.  相似文献   
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