Objective To observe the histological change of different waves in treating SD rats of the long-pulse 1064nm Nd:YAG laser and the 560～1200 nm intense pulse light,in order to provide the theory bases of non-ablative rejuvenation.Methods Two waves were used on experimental mice.The dermic thickness and the expression of collagen typesⅠand Ⅲwere detected by HE stain and immunohistochemical methods. Semiquantitative analysis was used to determine the mean of absorbance.Results Thedermal thicknesses and the mean of absorbance of collagen typesⅠandⅢin two different waves were higher than those in common control groups(P＜0.05).The effect of Nd:YAG laser groups were higher than IPL groups(P＜0.05).The expression of collagen typeⅠwas higher than that of collagen type Ⅲ(P＜0.001).Conclusion After Nd:YAG laser or IPL irradiation,the dermal thickness and collagen typesⅠandⅢof SD rats are increased.The effects of Nd:YAG laser are better than those of 560～1 200 nm IPL.The expression of collagen type Ⅲ is obviously more than that of collagen typeⅠin the early,whereas the expression of collagen typeⅠis obviously more than that of collagen type Ⅲin the later.It proves that the mechanism of dermal remodeling of non-ablative skin rejuvenation is mainly correlation with raising range and time of collagen typeⅠ.

Following extensive bowel resection， the intestinal tract undergoes a variety of adaptive responses to enhance bowel function． The purpose of this study was to determine the effect of glutamine-supplemented parenteral nutrition on mucosal cellularity and gut function． In addition， enterocyte gene expression of two relevant systems was also characterized and related to the structural and functional changes that occurred．Male Wistar rats underwent a 60％ small bowel resection and jugular vein catheterization and were randomized into two groups． The control group （n＝10） received a standard intravenous nutritional solution and the study group （n＝10） received a similar solution but enriched with alanylglutamine dipeptide． After 7 days blood was taken for amino acid analysis， and bowel was harvested to determine mucosal morphology and expression of mucosal cell glutaminase and IGF-I mRNA． Mesentery lymphnodes were cultured to determine the presence of bacteria and thus access bacteria translocation． Serum glutamine concentration and mucosal architecture were maintained in the study group compared to the controls． Seventy percent of lymphnodes were cultured positive in control vs． only 20％ in the study group （P＜0．05）． Jejunal mucosal glutaminase and ileum mucosal IGF-I mRNA increased twofold and threefold respectively compared to control animals．Parenteral nutrition supplemented with alanyl-glutamine dipeptide supports mucosal cellularity and regional immune function in rodents following intestinal resection， These alterations are associated with enhanced enterocyte expression of glutaminase and IGF-I． These changes may facilitate the structural and functional alterations which were observed in the glutamine treated animals．

Objective:To explore the image quality and its evaluation method using virtual grid under different tube voltages in the clinical chest X-ray exam.Methods:According to the conditions of chest X-ray photography commonly used in clinical practice, the corresponding thickness of plexiglass (20 cm, including CDRAD phantom) was determined as the experimental object. With a fixed tube loading of 4 mAs and the tube voltage from 60 to 125 kV, the experimental object was imaged in three ways: physical grid, none grid and virtual grid. The common physical parameters (CNR, σ, C, SNR), texture analysis (Angular second moment, texture Contrast, Correlation, Inverse difference moment, Entropy) and CDRAD phantom score (IQF inv) were evaluated. Two-way ANOVA test was used for each group of common physical parameters, and further pairwise comparisons were made. At the same time, applying virtual grids on the obtained images with chest anthropomorphic model and texture indexing the images with and without virtual grids, then rank sum test of paired sample can be conducted. Results:There were differences in image quality among the three groups of grid mode( P<0.05), and the physical grid delivered the best image quality. The tube voltage had an impact on all image quality evaluation indexes ( P<0.05). The tube voltage was positively correlated with CNR, SNR, angular second moment, inverse difference moment and IQF inv ( P<0.05), and negatively correlated with σ, C, texture contrast and entropy ( P<0.05). There was no significant correlation between the tube voltage and Correlation ( P>0.05). The chest anthropomorphic model images were used to evaluate the virtual grids, and the texture indexes (Angle second moment, Contrast, Correlation, Inverse difference moment, Entropy) were statistically significant (P<0.05). Conclusions:The virtual grid can improve the image quality of chest X-ray photography, and the image texture analysis method can be a useful supplement to the image quality evaluation parameters.

Objective:To explore and compare the impacts of different scanning protocols on image quality and radiation dose in chest computed tomography (CT) scans.Methods:A retrospective analysis was conducted for the data of 65 randomly selected patients who underwent chest CT scans using a tube voltage of 120 kV, the automatic modulation technique for tube current, and z-axis radiation dose modulation at the Emergency Department of our hospital from June to July 2023. The enrolled cases were divided into two groups: the high-resolution group ( n = 34) and the conventional group ( n = 31), with the settings for scanning protocols identical to those for phantom scans. For patients in both groups, thin-layer images of the cross-sections in the lung and mediastinal windows were reconstructed using thickness/intervals of 1 mm/1 mm and 2 mm/1 mm, respectively. Meanwhile, high-resolution and conventional CT scans were conducted using a Catphan500 phantom under a tube voltage of 120 kV and a tube current of 150 mAs. Of both scanning protocols, the high-resolution CT scan utilized the lung nodule-orientated scanning mode, pitch of 1.5, and a detector combination providing a collimation of 16 × 0.75 mm. In contrast, the conventional CT scan was performed using the body-orientated scanning mode, pitch of 0.813, and a detector combination providing a collimation of 16 × 1.5 mm. Then, the high-contrast resolutions of the phantom images obtained using the two scanning protocols were objectively evaluated. Both coronal chest images in the lung window and cross-sectional images in the mediastinal window were reconstructed with a thickness/interval of 5 mm/5 mm for both groups. Then, the obtained images were imported into the Radimetrics system to compare the body size-specific dose estimation (SSDE), doses to sensitive organs on the body surface, and scanning time of both groups. For the cross-sectional images in the mediastinal window, the contrast-noise-ratio (CNR), signal-to-noise ratio (SNR), and figure-of-merit (FOM) were measured and calculated at the fixed anatomical parts. For the cross-sectional images in the lung window, their quality was subjectively evaluated by two senior diagnostic radiologists. Results:The result of phantom scans indicated that high-resolution CT scans yielded images with an approximately 5% increase in the spatial resolution in the xy-plane and a nearly 20% increase in the spatial resolution along the z-axis compared to conventional CT scans. The result of clinical data demonstrated that the conventional group exhibited significantly higher doses to the thyroid and the female breast ( t = 2.8, 2.3, P < 0.05), along with notably elevated SNR, CNR, and FOM values of the right trapezius, compared to the high-resolution group ( t = 4.1, 5.8, z=4.4, P < 0.001). However, the high-resolution group manifested significantly higher SNR, CNR, and FOM values of the thoracic aorta compared to the conventional group ( t = 3.4, 4.4, z=3.4, P < 0.001). In addition, the cross-sectional and coronal images in the lung window of the clinical cases in the high-resolution group exhibited more stable quality, with subjective scores exceeding 4 and the average scores of both groups not statistically significantly different. Conclusions:For chest CT examination, high-resolution CT scans are more suitable for observations focusing on the details of the lungs and mediastinum, while conventional CT is more suitable for those centering on soft tissues on the body surface.