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251.
ObjectiveTo investigate the test-retest reliability and validity of the Kerlan-Jobe Orthopaedic Clinic shoulder and elbow score (KJOC) in elite Canoe Slalom athletes and determine its ability to predict future shoulder pain.DesignObservational study with embedded test-retest reliability study.SettingBritish Canoe Slalom National Training Centre.ParticipantsNineteen athletes from the British Canoe Slalom team for the 2019 season.Main outcome measuresThe KJOC was completed at the start of winter training and start of the 2019 competitive season. Current, historical (6-months pre-questionnaire) and prospective (4-months post-questionnaire) shoulder injuries were recorded.ResultsTest-retest reliability was found to be excellent (ICC3,1 = 0.97), with a minimal detectable change (MDC95%) of 6.7. Compared to uninjured athletes, currently injured and historically injured athletes scored significantly lower (p = 0.002 and p = 0.011, respectively), with the difference between means > MDC95%. A cut-off of 88 was found to be predictive of shoulder pain (AUC: 0.779; sensitivity: 0.60; specificity: 0.95; positive likelihood ratio: 11.4).ConclusionThe KJOC demonstrated excellent reliability and can distinguish between athletes with and without current or historical shoulder pain. A KJOC score of <88 was associated with increased risk of shoulder pain. The KJOC should be completed as part of a risk profile for shoulder pain.  相似文献   
252.
PurposeAlthough skin cutaneous melanoma (SKCM) is a relatively immunotherapy-sensitive tumor type, there is still a certain fraction that benefits less from treatment. Ferroptosis has been demonstrated to modulate tumor progression in many cancer types. This study focused on ferroptosis-related genes to construct a prognostic model for SKCM patients.Materials and methodsGene expression profiles of SKCM samples were obtained from public databases. Unsupervised consensus clustering was used to determine molecular subtypes related to ferroptosis. Least absolute shrinkage and selection operator (LASSO) and stepwise Akaike information criterion (stepAIC) were applied to construct a prognostic model based on differentially expressed genes between two molecular subtypes.ResultsC1 and C2 subtypes were identified with differential prognosis and immune infiltration. A 7-gene prognostic model was constructed to classify samples into high-FPRS and low-FPRS groups. Low-FPRS group with favorable prognosis had higher immune infiltration and more enriched immune-related pathways than the high-FPRS group. The two groups showed distinct sensitivity to immunotherapy, with the low-FPRS group predicted to have more positive response to immunotherapy than the high-FPRS group. A nomogram based on the FPRS score and clinical features was built for more convenient use.ConclusionsThe critical role of ferroptosis involved in SKCM development was further validated in this study. The prognostic model was efficient and stable to be applied in clinical conditions to support clinicians in determining personalized therapy for SKCM patients especially those with metastasis.  相似文献   
253.
Acinar cell carcinoma (ACC) is a rare pancreatic malignancy with distinctive clinical, molecular, and morphological features. The long-term survival of ACC patients is substantially superior to that of pancreatic adenocarcinoma patients. As there are no significant patient series about ACCs, our understanding of this illness is mainly based on case reports and limited patient series. Surgical resection is the treatment of choice for patients with the disease restricted to one organ; however, with recent breakthroughs in precision medicine, medicines targeting the one-of-a-kind molecular profile of ACC are on the horizon. There are no standard treatment protocols available for people in which a total surgical resection to cure the condition is not possible. As a result of shared genetic alterations, ACCs are chemosensitive to agents with activity against pancreatic adenocarcinomas and colorectal carcinomas. The role of neoadjuvant or adjuvant chemoradiotherapy has not been established. This article aims to do a comprehensive literature study and present the most recent information on acinar cell cancer.  相似文献   
254.
255.
It was aimed to investigate the compressibility, compactibility, powder flow and tablet disintegration of a new excipient comprising magnesium (Mg) silicate co-processed (5%–85% w/w) onto chitin, microcrystalline cellulose (MCC) and starch as the hydrophilic polymers of interest. Initially, the mechanism of tablet disintegration was studied by measuring water infiltration rate, moisture sorption, swelling capacity and hydration ability. Moreover, the powders compression behavior was carried out by applying Kawakita model of compression analysis in addition to porosity and radial tensile strength measurements. In vitro drug release of compacts made of 400?mg ibuprofen and 300?mg of the hydrophilic polymers containing 30% w/w Mg silicate co-precipitate was investigated in phosphate buffer (pH 7.8). This work demonstrated that the incorporation of Mg silicate to the hydrophilic polymers lead to the improvement of powder flowability, compactibility, stability (with regard to storage conditions), compacts crushing strength, and disintegration time in addition to faster drug release. The overall findings are practically advantageous in the context of finding a low cost and multifunctional co-processed excipient of natural origins.  相似文献   
256.
BackgroundThe hair follicle is a unique structure, one of the most dynamic structures in mammalians, which can reproduce in every new cycle all the mechanism involved in its fetal development. Although a lot of research has been made about the human hair follicle much less has been discovered about the importance of the cytokeratins (CKs) in its development.ObjectiveStudy the immunohistochemical pattern of epithelial CKs during human hair follicle development.MethodsWe performed an immunohistochemical study using fresh post-mortem skin biopsies of human fetuses between 4 and 25 weeks of gestational age to study the expression of cytokeratins (CKs): CK1, CK10, CK13, CK14, CK16 and CK20 during human hair follicle fetal development.Study limitationsRestrospective study with a good number of makers but with a small population.Results/conclusionWe found that, the CKs were expressed in an intermediate time during follicular development. The epithelial CKs (CK1, CK14, CK10, CK13) and the epithelial CKs with a proliferative character such as CK16 were expressed first, as markers of cellular maturation and follicular keratinization. At a later phase, CK20 was expressed in more developed primitive hair follicles as previously discussed in literature.  相似文献   
257.
目的 该研究采用网络药理学和分子对接的研究方法结合体内实验探讨槐花散治疗溃疡性结肠炎(ulcerative colitis, UC)的主要化合物和靶点,并分析其作用机制。方法 利用多个数据库筛选药物活性成分、药物靶点和UC疾病基因,并进行拓扑分析,构建“化合物-药物靶点-疾病基因”关系网络。利用DAVID在线分析工具对候选靶点进行基因本体(Gene ontology, GO)功能和生物通路(KEGG)富集分析。通过SYBYL X2.0软件进行分子对接,获取总评分、共识评分和结合位点。利用硫酸葡聚糖钠盐(dextran sodium sulfate,DSS)建立UC小鼠模型,槐花散干预后,评估疾病活动指数和结肠病理,RT-qPCR检测白介素6(IL-6)、白介素17(IL-17)mRNA表达水平,Western Blot检测IL-6、IL-17蛋白表达水平。结果 槐花散中有20个化合物对应375个靶点对121个UC疾病基因产生影响。对72个关键靶点作GO功能分析筛选得303个GO条目,其中生物过程相关的条目223条,细胞组成相关的条目25条,分子功能相关的条目55条。KEGG富集分析筛选得到88条通路。分子对接结果显示关键靶点与对应的化合物有较好的结合活性。体内实验显示,槐花散可以改善UC小鼠DAI评分,下调IL-6、IL-17的表达,减轻结肠组织病理损伤。结论 槐花散治疗UC具有多成分、多靶点、多通路的特点,为槐花散治疗UC的进一步研究提供了理论依据。  相似文献   
258.
ObjectivesColonization and infection with third-generation cephalosporin-resistant Escherichia coli (3GCR-EC) are frequent in haematological and oncological patients. In this high-risk setting, German guidelines recommend single-room contact precautions (SCP) for patients with 3GCR-EC that are non-susceptible to fluoroquinolones (F3GCR-EC). However, this recommendation is controversial, as evidence is limited.MethodsWe performed a prospective, multicentre cohort study at four haematology and oncology departments assessing the impact of SCP on hospital-acquired colonization or bloodstream infection (BSI) with F3GCR-EC. Two sites performed SCP for F3GCR-EC patients including single rooms, gloves and gowns (SCP sites), and two did not (NCP sites). Active screening for 3GCR-EC was performed and isolates were characterized with molecular typing methods including whole genome sequencing and core genome multiple locus sequence typing to assess patient-to-patient transmission. Potential confounders were assessed by competing-risk regression analysis.ResultsWithin 12 months, 1386 patients at NCP sites and 1582 patients at SCP sites were included. Hospital-acquisition of F3GCR-EC was observed in 22/1386 (1.59%) and 16/1582 (1.01%) patients, respectively (p 0.191). There were 3/1386 (0.22%) patients with BSI caused by F3GCR-EC at NCP sites and 4/1582 (0.25%) at SCP sites (p 1.000). Patient-to-patient transmission occurred in three cases at NCP and SCP sites each (p 1.000). The number of patients needed to screen in order to prevent one patient-to-patient transmission of F3GCR-EC was determined to be 3729.ConclusionsUse of SCP had no significant impact on hospital-acquisition or patient-to-patient transmission of F3GCR-EC in this high-risk setting.  相似文献   
259.
260.
This research investigated the effects of different thermoplastics types and different kinds of straw on selected properties of polymer-straw boards. Polyethylene, polyethylene, and polystyrene of virgin and of recycled origin were used for bonding the boards. Three kinds of straw were used: rape (Brassica napus L. var. napus), triticale (Triticosecale Witt b m.), and rye (Secale L.). Five-layer polymer-straw boards were produced. The obtained boards differed in both the materials they were made of and the moisture content (7, 25, and 2% for the core, the middle, and the face layers, respectively), and 30% of straw particles were substituted with thermoplastics added to the face layers. It was found that properties of polymer-straw boards strongly depend on both the kind of straw and the type of polymer used. The best mechanical properties were obtained for rye straw and polystyrene or recycled polymers, whereas the best hydrophobic properties were observed for rape straw combined with recycled polyethylene or polypropylene. Although recycled polymers improved the hydrophobic properties of the boards, they impaired their mechanical properties in comparison with the reference ones. However, in terms of bending strength, they still met the requirements for heavy duty load-bearing boards for use in humid conditions (20 MPa for P7 boards according to EN 312).  相似文献   
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