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1.
Claudins are the major component of tight junctions, which form a primary barrier to paracellular diffusion and maintain cell polarity in normal epithelia and endothelia. In cancer cells, claudins play additional roles besides serving as components of the tight junctions, and participate in anoikis or invasion. Among the claudin family proteins, claudin‐1 has the most promising potential, both diagnostically and prognostically, in many types of cancers, including oral, gastric, liver, and colon cancers. However, conflicting results have been reported in relation to the degree of claudin‐1 expression and the prognosis, suggesting that the expression level of claudin‐1 alone is not sufficient to analyze the relationship between claudin‐1 and cancer progression. As endocytic trafficking of claudin‐1 has been reported in several epithelial cell types in vitro, we aimed to determine whether intracellular localization of claudin‐1 is the missing aspect between claudin‐1 and cancer. We investigated the expression of claudin‐1 in 83 tongue squamous cell carcinoma (TSCC) pathological specimens. Although the expression level of claudin‐1 based on immunohistochemistry was not associated with TSCC progression, within the high claudin‐1 expression group, the incidence of intracellular localization of claudin‐1 was correlated with cervical lymph node metastasis. In an in vitro experiment, claudin‐1 was constitutively internalized in TSCC‐derived cells. Motility of TSCC‐derived cells was increased by deficiency of claudin‐1, suggesting that the decrease in cell‐surface claudin‐1 promoted the cell migration. Therefore, intracellular localization of claudin‐1 at the invasion front may represent a promising diagnostic marker of TSCC.  相似文献   
2.
目的:比较白内障微创超声乳化手术前后角膜前表面屈光力(ASF)、角膜真实净屈光力(TNP)和总角膜屈光力(TCRP)分布特点及角膜前后表面曲率半径比(B/F ratio)差异。

方法:前瞻性研究。收集2020-12/2021-05就诊于潍坊眼科医院行2.2mm微切口超声乳化白内障吸除联合人工晶状体植入术的年龄相关性白内障患者156例156眼。术前及术后3mo行Pentacam眼前节生物测量仪检查,收集以角膜顶点和以瞳孔为中心2、4、6mm环上和区域内ASF、TNP和TCRP,以及手术前后B/F ratio。

结果:术后3mo,以角膜顶点为中心2mm直径环上和区域内ASF值较术前均无差异(均P>0.05),而4、6mm直径环上和区域内ASF值较术前均有差异(均P<0.05); 以瞳孔为中心2mm直径环上及区域内ASF值较术前均无差异(均P>0.05)。以角膜顶点为中心和以瞳孔为中心2、4、6mm直径环上和区域内TNP、TCRP值较术前均有差异(均P<0.05)。术前以角膜顶点为中心和瞳孔为中心在2mm与6mm之间环上和4mm与6mm之间环上TCRP值均有差异(均P<0.0167); 在2mm与6mm区域内TCRP值均有差异(均P<0.0167); 术后3mo,以角膜顶点为中心和瞳孔为中心环上TCRP值在2mm与6mm之间、4mm与6mm之间均有差异(均P<0.0167),而以角膜顶点为中心和瞳孔为中心区域内TCRP值仅在2mm与6mm直径范围内有差异(P<0.0167)。B/F ratio术前为81.79%±1.87%,术后3mo为80.68%±2.23%(P<0.001)。

结论:白内障手术前后以角膜顶点和以瞳孔为中心的不同直径环上及区域内各项角膜屈光力参数会有一定的变化和差异,人工晶状体度数计算的K值选择及基于角膜特性的人工晶状体个体化选择时应予以考虑。  相似文献   

3.
Mahomed F  Altini M  Meer S 《Oral diseases》2007,13(4):386-392
OBJECTIVES: The aim of this study was to investigate the potential use of E-cadherin, a tumour-suppressor gene product involved in establishing cell-cell adhesion and one of its associated proteins, beta-catenin, as markers of nodal metastasis in oral squamous cell carcinoma (OSCC). MATERIALS AND METHODS: Thirty invasive OSCCs in patients with (n = 19) and without (n = 11) nodal metastases, as confirmed on histopathologic examination of the resected regional lymph nodes (n = 30), were examined for E-cadherin and beta-catenin expression by immunohistochemistry. RESULTS: There was a highly significant association (P < 0.0001) between E-cadherin and beta-catenin expression and tumour differentiation by conventional Broders' grading of the whole tumour. Irrespective of the nodal status and invasive tumour front (ITF) grading score, however, loss of expression was recorded at the ITF in 28 (93%) of 30 tumours and 22 (73%) of 30 tumours stained for E-cadherin and beta-catenin respectively. CONCLUSION: The results of this study suggest an association between loss of expression of E-cadherin and beta-catenin and a lower degree of differentiation; however, their use as markers of nodal metastasis in OSCC appears unreliable.  相似文献   
4.
目的利用多维分析法对住院病案首页数据质量进行评价,以形成科学、系统的住院病案首页质控管理模式,提升住院病案首页填写质量。方法对某三甲医院2019年1月至12月的住院病案按照随机数字表法抽取3000份,采用多维分析法,从住院病案首页填报的完整性、准确性、住院病案首页优质率三个方面进行分析。结果该院住院病案首页数据的完整率、准确率及住院病案首页质量优质率分别为92.40%,96.03%和91.80%。住院病案首页中缺失较多的项目为RH血型、ABO血型、是否有31天再入院计划等;错误较多的项目为主要诊断、主要手术及操作及主要诊断、主要手术及操作编码。其中内科系统及重症医学科完整率高于外科系统,内科系统正确性及住院病案首页优质率高于外科系统和重症医学科,差异均有统计学意义(均P<0.05)。结论多维分析方法是住院病案首页数据质量控制的重要辅助工具,可为临床及医院管理人员进行住院病案首页数据质量控制提供科学的依据。  相似文献   
5.
Climate change in the last century was associated with spectacular growth of many wild Pacific salmon stocks in the North Pacific Ocean and Bering Sea, apparently through bottom-up forcing linking meteorology to ocean physics, water temperature, and plankton production. One species in particular, pink salmon, became so numerous by the 1990s that they began to dominate other species of salmon for prey resources and to exert top-down control in the open ocean ecosystem. Information from long-term monitoring of seabirds in the Aleutian Islands and Bering Sea reveals that the sphere of influence of pink salmon is much larger than previously known. Seabirds, pink salmon, other species of salmon, and by extension other higher-order predators, are tightly linked ecologically and must be included in international management and conservation policies for sustaining all species that compete for common, finite resource pools. These data further emphasize that the unique 2-y cycle in abundance of pink salmon drives interannual shifts between two alternate states of a complex marine ecosystem.Predator control of community structure and ecosystem function became a tenet of intertidal and nearshore marine ecology following early studies of Paine and others (13), yet with few exceptions (4, 5), until more recent times the idea has been less well appreciated for open oceans. Growing attention now is being paid to the overexploitation of pelagic species, particularly those at higher trophic levels currently and in the past, and effects on ocean ecosystems of the loss, or development, of top-down forcing (612).The prevailing view has long held that most biological change in ocean ecosystems, apart from human exploitation, is driven from the bottom up (1316). One striking example that has been linked to bottom-up processes driven by climate change is the burgeoning abundance of wild Pacific salmon (Oncorhynchus spp.), and in particular pink salmon (Oncorhynchus gorbuscha), in the subarctic North Pacific Ocean and Bering Sea (SNPO/BS). Underpinning the notion initially were studies that found (i) strong coherence between decadal patterns in the Aleutian Low pressure system, which exerts a large influence over climate in the North Pacific Ocean, and patterns in salmon production across a broad region of the SNPO/BS (17, 18); (ii) decadal patterns in primary production that could be explained by the effect of the Aleutian Low pressure system on basin scale wind fields (19); and (iii) decadal patterns in zooplankton, squid, and pelagic fish production that also were correlated with meteorological forcing over the North Pacific Ocean and consistent with patterns in primary production (20). Thus, the general explanation for waxing and waning abundances of salmon over the record in the 20th century was that physical forcing by shifts in the strength and position of the Aleutian Low altered winds, ocean temperatures, and primary and secondary production to the benefit or detriment of salmon. A decadal scale oscillation in the Aleutian Low, now often referred to as the Pacific Decadal Oscillation (PDO) (21), has been linked to numerous physical and biological variability in the SNPO/BS in addition to salmon abundance (2123).It was subsequently shown that salmon population responses and their relation to the PDO were out of phase between Alaska and the northwest coast of North America during much of the 20th century (24); that warm anomalies in coastal temperatures were associated with increased survival of salmon in Alaska; and that regional-scale variability in ocean temperature was a better predictor of salmon survival than large, basin-scale variability characterized by the PDO (25). A recent analysis from around the rim of the North Pacific Ocean found regional covariance in abundance of pink salmon, chum salmon (Oncorhynchus keta), and sockeye salmon (Oncorhynchus nerka) associated with the Aleutian Low, and with smaller scale spatially coherent, but regionally distinct, patterns in climate (26).Water temperature can be important to the early growth and survival of pink salmon fry directly by its effect on physiology and indirectly by its effect on the timing and development of zooplankton prey stocks in nursery areas, which commonly is advanced and greater in warmer years than in cooler years. In cooler springs, fry grow more slowly and a greater number die both from lack of food and from an increased susceptibility to predators (27, 28). For example, a conceptual model for Prince William Sound, Alaska, holds that, in years of abundant spring zooplankton, fry grow faster and remain longer in the shelter of inshore nurseries where they are protected from walleye pollock (Theragra chalcogramma) and Pacific herring (Clupea pallasii), two chief predators that remain offshore feeding primarily on swarms of large calanoid copepods and other macrozooplankton. In cooler years of lower zooplankton biomass inshore, fry grow more slowly, move offshore earlier, and suffer higher predation by pollock and herring due to spatial overlap, smaller size, and less alternative prey for those two predators (28).Although the relationship between climate and pink salmon survival is likely complex, fluctuations in abundance appear to be modulated in large measure directly and indirectly by the thermal environment in which a stock lives. Such a fundamentally bottom-up explanation is bolstered by observations of high growth and survival rates of pink salmon during the period of warmer ocean temperatures and population increase (29, 30), and at this time provides a more parsimonious explanation for population dynamics than would explanations invoking strictly top-down control across such a broad region. Now, however, several lines of evidence indicate that pink salmon themselves are having a large top-down influence on other salmon species, other upper trophic level pelagic species, plankton standing stocks, and by inference, the functioning of the open-ocean ecosystem in the SNPO/BS.  相似文献   
6.

Background

A vertical incision is recommended for cricothyroidotomy when the anatomy is impalpable, but no evidence-based guideline exists regarding optimum site or length. The Difficult Airway Society guidelines, which are based on expert opinion, recommend an 80–100 mm vertical caudad to cephalad incision in the extended neck position. However, the guidelines do not advise the incision commencement point. We sought to determine the minimum incision length and commencement point above the suprasternal notch required to ensure that the cricothyroid membrane would be accessible within its margins.

Methods

We measured using ultrasound, in 80 subjects (40 males and 40 females) without airway pathology, the distance between the suprasternal notch and the cricothyroid membrane, in the neutral and extended neck positions. We assessed the inclusion of the cricothyroid membrane within theoretical incisions of 0–100 mm in length made at 10 mm intervals above the suprasternal notch.

Results

In the 80 subjects, the distance ranged from 27 to 105 mm. Movement of the cricothyroid membrane on transition from the neutral to extended neck position varied from 15 mm caudad to 27 mm cephalad. The minimum incision required in the extended position was 70 mm in males and 80 mm in females, commencing 30 mm above the suprasternal notch.

Conclusions

An 80 mm incision commencing 30 mm above the suprasternal notch would include all cricothyroid membrane locations in the extended position in patients without airway pathology, which is in keeping with the Difficult Airway Society guidelines recommended incision length.  相似文献   
7.
8.
This paper attempts to answer the question of why social caseworkers have ongoing supervision by exploring the historical evolution of social work supervision. Supervision has withstood the many changes in the field since its beginning in the late 1800s and has been reinterpreted to fit the prevailing theories guiding practice, thus avoiding obsolescence. Supervision began as an educational device, then evolved into a practice tool, later became a therapeutic method, and then became a separate entity from therapy.  相似文献   
9.
Invasion is a defining feature of malignancy, but the mechanisms of invasion in many common cancers, including gynaecological malignancies, remain unclear. However, it has been proposed that malignant cells may usurp a normal embryological process, epithelial–mesenchymal transition (EMT), as a means of acquiring migratory capacity. The synergistic role of the tumour microenvironment in EMT induction has also been explored and helps to explain the spatially restricted distribution of EMT at the deep tumour margin (invasive front). Furthermore, tumour cells undergoing EMT may acquire cancer stem cell characteristics, and this may be relevant to the entire metastatic process and to tumour recurrence and treatment failure. Nevertheless, doubts persist regarding the role of EMT in malignant progression in vivo, partly because few studies have correlated molecular and histological alterations in clinical pathology specimens. In the current review we summarize the evidence for EMT in the common gynaecological epithelial malignancies, and discuss the morphological and immunohistochemical changes occurring at the invasive tumour front that may represent EMT‐like processes. The possibility that carcinosarcomas represent a variant type of EMT with ‘fixed’ mesenchymal differentiation is also considered. Diagnostic histopathologists are ideally placed to critically evaluate the role of EMT in gynaecological and other types of malignancy.  相似文献   
10.
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