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101.
目的:总结肝脏少见肿瘤的CT特点,以提高其CT诊断水平.材料和方法:回顾性分析9例肝脏少见肿瘤的临床、病理及CT特点.结果:其CT特点包括:(1)3例肝肉瘤类肿瘤体积均较大,易坏死囊变,发展快;其中胚胎性肉瘤内见分隔状软组织影;(2)1例肝类癌内见钙化影;(3)1例肝非何杰金氏淋巴瘤肝内多个类圆形低密度肿块,环形增强及腹膜后淋巴结肿大;(4)1例肝血管淋巴管瘤病见多房囊性低密度及纤维分隔影,周边见斑点状、条状钙化,肿瘤周围及其内纤维分隔明显增强;(5)3例肝血管平滑肌脂肪瘤增强后均见中心斑点状增强血管影.结论:典型CT表现结合临床其它资料,可提高肝脏少见肿瘤CT诊断的准确性.  相似文献   
102.
BackgroundIn diabetic retinopathy (DR) screening programmes feature-based grading guidelines are used by human graders. However, recent deep learning approaches have focused on end to end learning, based on labelled data at the whole image level. Most predictions from such software offer a direct grading output without information about the retinal features responsible for the grade. In this work, we demonstrate a feature based retinal image analysis system, which aims to support flexible grading and monitor progression.MethodsThe system was evaluated against images that had been graded according to two different grading systems; The International Clinical Diabetic Retinopathy and Diabetic Macular Oedema Severity Scale and the UK’s National Screening Committee guidelines.ResultsExternal evaluation on large datasets collected from three nations (Kenya, Saudi Arabia and China) was carried out. On a DR referable level, sensitivity did not vary significantly between different DR grading schemes (91.2–94.2.0%) and there were excellent specificity values above 93% in all image sets. More importantly, no cases of severe non-proliferative DR, proliferative DR or DMO were missed.ConclusionsWe demonstrate the potential of an AI feature-based DR grading system that is not constrained to any specific grading scheme.Subject terms: Diagnosis, Medical imaging  相似文献   
103.
BACKGROUND: Coronary artery calcification is a common feature of atherosclerosis, occurring in 90% of angiographically significant lesions. There is recent evidence that coronary artery calcification is frequent in hemodialysis patients and it has been suggested that this increased incidence may be associated to uremia-related factors. The development and progression of coronary artery calcification is similar to osteogenesis. The aim of this study was to evaluate the relationship between coronary artery calcification, uremia-related factors, and bone histomorphometry in hemodialysis patients. METHODS: A total of 101 hemodialysis patients were assessed for biochemical markers of inflammation, oxidative stress, and bone metabolism. Subsequently, they were submitted to multislice coronary tomography (MSCT) and transiliac bone biopsy. RESULTS: The median calcium score was 116.2 (range 0 to 5547). Fifty-two percent of the patients showed moderate and severe coronary artery calcification, 20% had calcium scores greater than 1000. In univariate analysis, age (r= 0.57, P < 0.000001), osteoprotegerin (OPG) (r= 0.44, P= 0.00002), and body mass index (BMI) (r= 0.24, P= 0.01) correlated positively with calcium score. Bone trabecular volume and trabecular thickness correlated negatively with calcium score (r=-0.24, P= 0.02; r=-0.22, P= 0.03). There was a correlation of borderline significance between calcium score and C-reactive protein (CRP) (r= 0.18, P= 0.062). The multiple linear regression analysis identified OPG as the only variable independently associated with coronary artery calcification. CONCLUSION: Coronary artery calcification is highly prevalent in the hemodialysis population and is associated with older age, higher BMI, inflammation and reduced trabecular bone volume. Higher OPG is independently associated with coronary artery calcification and may represent an incomplete self-defensive response to the progression of atherosclerosis in hemodialysis patients.  相似文献   
104.

Background

In recent years, a role for the immune system in the pathogenesis of psychiatric diseases has gained increased attention. Although bipolar disorder appears to be associated with altered serum cytokine levels, a putative immunological contribution to its patho-physiology remains to be established. Hitherto, no direct analyses of cerebrospinal fluid (CSF) cytokines in patients with bipolar disorder have been performed.

Methods

We analyzed CSF cytokine concentrations in euthymic patients with diagnosed bipolar disorder type I (n = 15) or type II (n = 15) and healthy volunteers (n = 30) using an immunoassay-based protein array multiplex system.

Results

The mean interleukin (IL)-1β level (4.2 pg/mL, standard error of the mean [SEM] 0.5) was higher and the IL-6 level (1.5 pg/mL, SEM 0.2) was lower in euthymic bipolar patients than in healthy volunteers (0.8 pg/mL, SEM 0.04, and 2.6 pg/mL, SEM 0.2, respectively). Patients with 1 or more manic/hypomanic episodes during the last year showed significantly higher levels of IL-1β (6.2 pg/mL, SEM 0.8; n = 9) than patients without a recent manic/hypomanic episode (3.1 pg/mL, SEM 1.0; n = 10).

Limitations

All patients were in an euthymic state at the time of sampling. Owing to the large variety of drugs prescribed to patients in the present study, influence of medication on the cytokine profile cannot be ruled out.

Conclusion

Our findings show an altered brain cytokine profile associated with the manifestation of recent manic/hypomanic episodes in patients with bipolar disorder. Although the causality remains to be established, these findings may suggest a pathophysiological role for IL-1β in bipolar disorder.  相似文献   
105.
In this article a literature review shows great differences in the reported prevalences of nail biting and the consequences of intense nail biting, such as repetitive loading of the TMJ, have hitherto been neglected. Five case reports of severe nail biters with craniomandibular disorders demonstrate the response to ceased nail biting. Some psychological studies dealing with nail biting are also presented.  相似文献   
106.
107.
We evaluated the usefulness of blood group genotyping as a supplement to hemagglutination to determine the red blood cell (RBC) antigen profile of polytransfused patients with hematological diseases and renal failure. Seventy‐nine patients were selected. They all received more than three units of blood and eight (10%) had already clinical significant alloantibodies occurring alone or in combination against Rh, K, Fya, and Di antigens. DNA was prepared from blood samples and RHCE*E/e, KEL*01/KEL*02, FY*01/FY*02 and JK*01/JK*02 alleles were determined by using PCR‐RFLP. RHD*/RHD*Ψ and RHCE*C/c were tested using multiplex PCR. Discrepancies for Rh, Kell, Duffy, and Kidd systems were found between the phenotype and genotype‐derived phenotype in 16 of the 38 chronically transfused patients. The genotypes of these patients were confirmed by DNA array analysis (HEA Beadchip?; Bioarray Solutions, Warren, NJ). Genotyping was very important for the determination of the true blood groups of the polytransfused patients, helped in the identification of suspected alloantibodies and in the selection of antigen‐negative RBCs for transfusion. J. Clin. Lab. Anal. 24:311–316, 2010. © 2010 Wiley‐Liss, Inc.  相似文献   
108.
Aim: This study investigates the relationship between transepidermal water loss (TEWL) and skin permeability to tritiated water as a rapid assessment of the integrity of the barrier properties of skin as part of in vitro skin permeation studies.
Methods: TEWL values before and during the experimental period were measured using three evaporimeters (A, B, and C) representing different measuring principles and technologies. Single application of tritiated water was dosed on dermatomed human skin samples in a flow-through diffusion cell system. Radioactivity of the absorbed dose and the removable dose residues was counted to determine percent dose and flux rate. These data were further combined with TEWL values to analyze the correlation.
Results: Evaporimeter C, a closed chamber–condenser technology, had higher measurement capacity than other instruments, evaporimeter A, an open chamber, and evaporimeter B, a closed chamber ( P <0.001). The baseline TEWL value correlated with tritiated water flux ( r =0.34, P =0.04). The pattern of tritiated water expressed as percent dose permeated into receptor fluid was similar to that of TEWL values.
Conclusion: These data indicate that TEWL can be ascribed to be a measure of skin water barrier function. Further work should be conducted to interpret the significance of measuring TEWL by evaporimetry.  相似文献   
109.
We report a rare case in a female infant (age, 3.5 months) with primary immunodeficiency (IFN-γ/IL-12 pathway defect) who presented with suppurative lymphadenitis after Mycobacterium bovis BCG vaccination. The strain of M. bovis BCG identified was found to be resistant to isoniazid and rifampin. The patient was treated with a special pharmacological regimen involving isoniazid (in a limited, strategic manner), ethambutol, streptomycin, and IFN-γ, after which there was complete resolution of the lesions.  相似文献   
110.
ABSTRACT Objectives: In Chile, little information about the use of standard precautions (SP) among health care workers (HCWs) exists. As part of a larger study to tailor and test an HIV prevention intervention for community HCWs, this study describes the observed frequency with which appropriate SP were used by HCWs in low-income community clinics of Santiago. Also, the availability of supplies is described.
Sample: A total of 52 structured observations with potential contamination with body fluids were done.
Results: HCWs used SP inconsistently, especially neglecting hand washing, surface cleaning, and cleaning of shared materials. Lack of materials contributed in some instances of failure to use SPs, especially wiping surfaces and safe disposal of sharp instruments, as shown by a positive correlation between use of SP and availability of materials. Essential materials were usually available. Although more education should relate to a better understanding of the importance of SP, no difference was found between professionals and paraprofessionals in the use of SP.
Conclusions: It is clear that the initial training, continuing education, and ongoing support for practicing SP are not adequate. Training should be offered to HCWs involved in caring for clients at community clinics to stop the spread of HIV or other infectious diseases in health care settings.  相似文献   
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