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Objective: Nucleolar organizer regions (NORs) are DNA coils that transcribe to ribosomal RNA. The NOR-associated protein, termed argyrophilic NOR (AgNOR), was visible within the nucleus by staining with silver nitrate examination via the light microscope. AgNOR counting is a proliferation marker and may help in the diagnosis and prognosis of various neoplastic lesions. Aneuploidy (abnormal DNA content) can predict the progression, survival and prognosis of the tumors. The aim of this study was to evaluate the role of AgNORs, DNA ploidy status, and total S-phase fraction (TSPF) as prognostic parameters in malignant salivary gland tumors (MSGTs). Methods: The current study is a retrospective study on a cohort of MSGTs (N=47), to assess AgNORs using Silver Nitrate stain, DNA index (DI), and TSPF using flow cytometry (FCM). Data including tumor size and site, lymphovascular invasion (LVI), lymph node metastasis (LNM) were collected. Results: The AgNORs count was statistically significant with MSGT type. DI was found to have a significant association with tumor site, tumor size and MSGT type. In addition, TSPF was found to be significantly associated with LVI. A moderate positive correlation was noted between AgNORs count and TSPF. LNM, tumor site, high AgNORs and low DI were all associated with short disease-free survival (DFS) and poor overall survival (OS). Conclusion: The present study revealed that high AgNORs count, DNA aneuploidy and TSPF had a poor influence on MSGTs prognosis.  相似文献   
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Journal of Pharmacokinetics and Pharmacodynamics - Clinical trials in patients with ulcerative colitis (UC) face the challenge of high and variable placebo response rates. The Mayo Clinical Score...  相似文献   
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Graefe's Archive for Clinical and Experimental Ophthalmology - To clarify the prognosis of corneal perforation, we compared the etiology and characteristics of patients with traumatic and...  相似文献   
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The notarium is a rigid bony structure, which resulted from the fusion of thoracic vertebrae of some pterosaurs and birds. It is high variable, ranging from two to six fused thoracic vertebrae. In this study, we reviewed and analyzed approximately 270 specimens of neornithine birds (representing 80% of the living orders) and some fossils in order to identify the number of fused vertebrae, degree and sites of vertebral fusion, occurrence of sutures, and other structures of potential phylogenetic and functional significance. These data were analyzed using a recent time-calibrated molecular phylogenetic tree and principal component analyses analysis evaluating the relationship with long bones in order to reconstruct macroevolutionary trends related to the evolution of the notarium. The occurrence of this structure shows a mosaic distribution over neornithine phylogeny, originating several times independently, especially during the Paleogene, in predominantly ground-dwelling forms. The notarium of these groups is characterized by: neural spines fused into single structure, intervertebral openings small to absent, large ventral keels forming ventral plates, and fused transverse processes. Derived neornithines, such as aquatic forms and long-legged birds, have a tendency to display a decreased degree of fusion between the vertebrae, which may indicate a reduction or disappearance of the notarium.  相似文献   
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Journal of Interventional Cardiac Electrophysiology - Delineate retrospectively and prospectively the incidence and characteristics of transient ST-segment elevation during transseptal puncture....  相似文献   
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Background

As the population ages in developed countries, the number of Pap smears for cervical cancer screening of older women is increasing. There is concern that cervical atrophy may cause misinterpretation of results for this segment of the population. The present study evaluated the accuracy of screening for high-grade intraepithelial lesions (HSILs) in women younger or older than 50 years, to determine whether aging affects cytological interpretation.

Methods

Patients with HSIL cytology (N = 1565) were dichotomized into those aged 20–49 years or aged ≥ 50 years. Association between histology results and age was examined. Pearson’s chi-squared test and Cochran-Armitage trend test were used for statistical analysis.

Results

The positive predictive value (PPV) for cervical intraepithelial neoplasia (CIN)2 and worse was 65.2% (62/95) in older women but 87.3% (482/552) in younger women (p < 0.001). Older patients had a significantly lower PPV (p = 1.69 × 10–8). Separately analyzing chronic cervicitis, CIN1 and overt cancer grouped together, compared with another group composed of CIN2 and CIN3, we found that the PPV for CIN2 and CIN3 was lower in older than in younger women [44.2% (42/95)-vs-82.4% (455/552), p < 0.001], respectively.

Conclusions

HSILs are associated with a wide range of disease categories as age increases, and the accuracy of HSIL interpretation is lower in older women.

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In Becker muscular dystrophy (BMD), muscle weakness progresses relatively slowly, with a highly variable rate among patients. This complicates clinical trials, as clinically relevant changes are difficult to capture within the typical duration of a trial. Therefore, predictors for disease progression are needed. We assessed if temporal increase of fat fraction (FF) in BMD follows a sigmoidal trajectory and whether fat fraction at baseline (FFbase) could therefore predict FF increase after 2 years (ΔFF). Thereafter, for two different MR-based parameters, we tested the additional predictive value to FFbase. We used 3-T Dixon data from the upper and lower leg, and multiecho spin-echo MRI and 7-T 31P MRS datasets from the lower leg, acquired in 24 BMD patients (age: 41.4 [SD 12.8] years). We assessed the pattern of increase in FF using mixed-effects modelling. Subsequently, we tested if indicators of muscle damage like standard deviation in water T2 (stdT2) and the phosphodiester (PDE) over ATP ratio at baseline had additional value to FFbase for predicting ∆FF. The association between FFbase and ΔFF was described by the derivative of a sigmoid function and resulted in a peak ΔFF around 0.45 FFbase (fourth-order polynomial term: t = 3.7, p < .001). StdT2 and PDE/ATP were not significantly associated with ∆FF if FFbase was included in the model. The relationship between FFbase and ∆FF suggests a sigmoidal trajectory of the increase in FF over time in BMD, similar to that described for Duchenne muscular dystrophy. Our results can be used to identify muscles (or patients) that are in the fast progressing stage of the disease, thereby facilitating the conduct of clinical trials.  相似文献   
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