肠系膜上静脉血栓形成临床特点及预后相关因素分析

目的 探讨肠系膜上静脉血栓形成（SWVT）临床特征、诊治方法,研究预后相关因素。方法 回顾性分析华北理工大学附属医院2005~2015年40例肠系膜上静脉血栓形成患者临床资料。结果 主要症状有腹痛、腹胀、发热及呕吐等。40例患者中,29例行单纯抗凝治疗,11例行手术治疗,6例患者30天内死亡。与30天生存率相关的因素为肠切除和确诊前持续时间。结论 该疾病症状不典型,增强CT对诊断具有重要意义,抗凝为基础,保守治疗无效时手术治疗为主要治疗手段,肠切除和确诊前持续时间是影响SMVT 30天生存率相关因素。     

More precise localization of nasal tumors associated with chronic exposure of F-344 rats to formaldehyde gas

Considerable interest and research have resulted from the finding that squamous cell carcinomas, polypoid adenomas, and a small number of other nasal neoplasms occurred in F-344 rats following chronic inhalation exposure to formaldehyde. These tumors were reported to originate in the anterior portion of the nasal cavity but their precise location in the nose was not determined. Histologic sections from the nasal passages of these rats have been reexamined and the location of each tumor has been recorded. The majority of squamous cell carcinomas occurred on the anterior portion of the lateral aspect of the nasoturbinate and adjacent lateral wall (57%) or the midventral nasal septum (26%). Polypoid adenomas were confined to a small region of the anterior nasal cavity and were restricted to the free margins of the naso-and maxilloturbinates and lateral wall adjacent to these margins. One neoplasm, considered to be the malignant counterpart of the polypoid adenoma, originated on the dorsal margin of the maxilloturbinate in the same region of the nose. Remaining neoplasms were generally too large or too poorly preserved for assessment of their site of origin. Mechanistic studies directed toward a better understanding of the nasal carcinogenicity of formaldehyde, or other nasal carcinogens, should take into account the anatomic sites of origin of the neoplasms whenever this can be determined.     

A re-evaluation of the role of C3 in B-cell activation

There is considerable evidence that, in vivo, C3 is required for the induction and maintenance of memory cells of the B-cell lineage. Recent data from in-vitro systems indicate that ligation of C3 receptors on B cells can activate these cells, and that appropriately presented C3 split products can act as B-cell growth factors. Here, Gerry Klaus and John Humphrey propose that in vivo these growth-promoting effects of C3 may operate within the microenvironment of germinal centres, where B cells encounter antigen-antibody-C3 complexes on the surfaces of follicular dendritic cells.     

Impact of Precursor Concentration on Perovskite Crystallization for Efficient Wide-Bandgap Solar Cells

High-crystalline-quality wide-bandgap metal halide perovskite materials that achieve superior performance in perovskite solar cells (PSCs) have been widely explored. Precursor concentration plays a crucial role in the wide-bandgap perovskite crystallization process. Herein, we investigated the influence of precursor concentration on the morphology, crystallinity, optical property, and defect density of perovskite materials and the photoelectric performance of solar cells. We found that the precursor concentration was the key factor for accurately controlling the nucleation and crystal growth process, which determines the crystallization of perovskite materials. The precursor concentration based on Cs_0.05FA_0.8MA_0.15Pb(I_0.84Br_0.16)₃ perovskite was controlled from 0.8 M to 2.3 M. The perovskite grains grow larger with the increase in concentration, while the grain boundary and bulk defect decrease. After regulation and optimization, the champion PSC with the 2.0 M precursor concentration exhibits a power conversion efficiency (PCE) of 21.13%. The management of precursor concentration provides an effective way for obtaining high-crystalline-quality wide-bandgap perovskite materials and high-performance PSCs.     

Influence of Mineralogical Structure of Mold Flux Film on Heat Transfer in Mold during Continuous Casting of Peritectic Steel

The mineralogical structure of flux films is a critical factor in controlling heat transfer in the mold and avoiding the longitudinal cracking of slabs during the continuous casting of peritectic steel. In this study, the layered structure, crystallization ratio, mineralogical species, and morphology features of flux films were characterized by optical microscopy, X-ray diffraction, and electron-probe microanalysis. Microstructural observation revealed that the normal flux films for peritectic steels present a multilayered structure and high crystallization ratio (60~90 vol%), mainly composed of well-developed crystalline akermanite and cuspidine. In contrast, the films with outstanding flux characteristics with abundant longitudinal cracks on the slab surface have a low crystallization ratio (<50 vol%) or vast crystallite content (>80 vol%). Furthermore, heat transfer analysis showed that the low crystallization ratio and the vast crystallite content of flux films worsen the heat transfer rate or uniformity in the mold, whereas the appropriate thickness and cuspidine content of flux films can improve the heat transfer performance. From the above results, it is concluded that using strong crystalline flux to obtain the ideal mineral phase structure of flux film is one of the important measures for reducing longitudinal cracks during continuous casting of peritectic steel slabs.     

Effect of goal-directed fluid therapy on renal function in critically ill patients: a systematic review and meta-analysis

ObjectiveTo evaluate whether goal-directed fluid therapy (GDFT) reduces the risk of renal injury in critical illness.MethodsMEDLINE via PubMed, EMBASE, CENTRAL and CBM was searched from inception to 13 March 2022, for studies comparing the effect of GDFT with usual care on renal function in critically ill patients. GDFT was defined as a protocolized intervention based on hemodynamic and/or oxygen delivery parameters. A fixed or random effects model was applied to calculate the pooled odds ratio (OR) based on heterogeneity through the included studies.ResultsA total of 28 studies with 9,019 patients were included. The pooled data showed that compared with usual care, GDFT reduced the incidence of acute kidney injury (AKI) in critical illness (OR 0.62, 95% confidence interval (CI) 0.47 to 0.80, p< 0.001). Sensitivity analysis with only low risk of bias studies showed the same result. Subgroup analyses found that GDFT was associated with a lower AKI incidence in both postoperative and medical patients. The reduction was significant in GDFT aimed at dynamic indicators. However, no significant difference was found between groups in RRT support (OR 0.88, 95% CI 0.74 to 1.05, p= 0.17). GDFT tended to increase fluid administration within the first 6 h, decrease fluid administration after 24 h, and was associated with more vasopressor requirements.ConclusionsThis meta-analysis suggests that GDFT aimed at dynamic indicators may be an effective way to prevent AKI in critical illness. This may indicate a benefit from early adequate fluid resuscitation and the combined effect of vasopressors.