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361.
目的:研究胃癌患者血清糖链抗原125(CA125)、糖链抗原724(CA724)、癌胚抗原(CEA)、糖链抗原199(CA199)水平的表达及与临床病理特征的关系。方法:选取2016年5月-2017年8月我院收治的胃癌患者94例记为胃癌组,胃部良性病变患者82例记为良性病变组,另取同期于我院接受体检的健康志愿者80例记为对照组。分别测定三组受试者血清CA125、CA724、CEA、CA199水平,并分析上述指标与胃癌患者临床病理特征的关系,并观察胃癌患者各指标单独检测和联合检测的阳性率。结果:三组受试者血清CA125、CA724、CEA、CA199水平整体比较差异有统计学意义(P0.05),胃癌组、良性病变组、对照组的血清CA125、CA724、CEA、CA199水平呈逐渐降低趋势,两两对比差异有统计学意义(P0.05)。不同性别的胃癌患者CA125、CA724、CEA、CA199水平比较差异无统计学意义(P0.05),年龄60岁、TNM分期为Ⅲ-Ⅳ期、肿瘤大小≥5 cm2的胃癌患者CA125、CA724、CEA、CA199水平均高于年龄≤60岁、TNM分期为Ⅰ-Ⅱ期、肿瘤大小5 cm2的胃癌患者,差异有统计学意义(P0.05)。联合检测的胃癌阳性率高于CA125、CA724、CEA、CA199单独检测,且CA724单独检测高于CA125、CEA、CA199单独检测,差异有统计学意义(P0.05)。结论:胃癌患者血清CA125、CA724、CEA、CA199水平较高,与患者的年龄、TNM分期、肿瘤大小等因素有关,且联合检测的胃癌检出率较高,可为胃癌的早期诊断提供指导作用。  相似文献   
362.
摘要 目的:探讨非小细胞肺癌(NSCLC)组织程序性细胞死亡蛋白1配体(PD-L1)、甲状腺转录因子-1(TTF-1)、突触素(SYN)表达与临床病理特征及预后的关系。方法:对2013年2月至2015年2月期间在我院治疗的97例NSCLC患者进行研究。检测NSCLC组织以及癌旁组织中PD-L1、TTF-1、SYN表达。分析PD-L1、TTF-1、SYN表达与临床病理特征的相关性。Kaplan-Meier生存曲线分析不同PD-L1、TTF-1、SYN表达患者总生存率的差异。Cox比例风险回归分析NSCLC患者预后的影响因素。结果:与癌旁组织相比,NSCLC组织中PD-L1、TTF-1阳性表达升高,SYN阴性表达升高(P<0.05)。PD-L1、TTF-1、SYN表达均与TNM分期和淋巴结转移相关(P<0.05)。PD-L1、TTF-1阴性患者的生存率分别高于PD-L1、TTF-1阳性患者,SYN阴性患者的生存率低于SYN阳性患者(P<0.05)。Cox比例风险回归分析结果显示,TNM分期、PD-L1阳性表达、TTF-1阳性表达、SYN阴性表达、淋巴结转移是NSCLC患者预后的影响因素(P<0.05)。结论:NSCLC组织中PD-L1、TTF-1阳性表达升高,SYN阴性表达升高,并且均与TNM分期、淋巴结转移和预后相关,其在NSCLC的诊断和预后评估中具有一定临床价值。  相似文献   
363.
[目的]了解湛江市外来入侵植物的种类特征、生活型、起源和危害情况等,对制定预防和控制管理措施提供参考。[方法]以野外调查为主,结合文献资料、网络资源以及标本数据,确定湛江市外来入侵植物的种类、生活型、原产地、引入途径,并进行评估及划分危害等级。[结果]湛江市现有外来入侵植物共112种(含变种),隶属于37科89属,其中,菊科(21种)、禾本科(13种)和豆科(13种)为种类较多的3个科,三者合计占湛江市外来入侵植物总种数的41.96%。湛江市外来入侵植物中以草本植物居多(98种),占入侵植物总数的87.50%。入侵植物主要来源于美洲,共82种,占总种数的73.21%;且55.36%(62种)的入侵植物为有意引入。从危害等级看,外来入侵植物中恶性入侵种(1级)23种,严重入侵种(2级)35种,局部入侵种(3级)21种,一般入侵种(4级)15种,有待观察种(5级)18种。[结论]湛江市的外来入侵植物种类繁多,这与湛江独特的地理位置以及日趋频繁的人类活动息息相关,应当加强监管与防范,及时对外来物种进行治理。  相似文献   
364.
通过野外调查研究了鄱阳湖滩地水生植物物种多样性和群落多样性,并将遥感(RS)技术与地理信息系统(GIS)技术和全球定位系统(GPS)技术相结合,研究了鄱阳湖滩地植被的分布、面积和生物量,绘制了滩地植被生物量等级分布图.结果如下1)鄱阳湖滩地分布有水生植物28科、56属、95种3变种,其中灰化苔草(Carexcineras-cens)、阿及苔草(C.argi)、草(Phalaris arundinacea)、获(Miscanthus sacchariflorus)、芦苇(Phragmites communis)、单性苔草(C.unisexualis)和针蔺(Eleochari valleculosa)7种植物为主要优势种;2)鄱阳湖滩地植被可划分为12个群丛类型,其中灰化苔草群丛(C.cinerascens Ass.)和阿及苔草群丛(C.argiAss.)占优势,"荻+芦-灰化苔草群丛”(M.sacchariflorus+P.communis-C.cinerascens Ass.)次之;3)鄱阳湖滩地植被主要分布于该湖的南部和西部,2000年4月16日其总面积为1018.74km2,占鄱阳湖总面积的33.65%,其中单位面积生物量≥4000g·m-2的植被面积为444.53km2,分别占鄱阳湖总面积和滩地植被总面积的14.68%与43.63%;4)2000年4月16日全湖滩地植被总生物量为3.81×106t(鲜重),全湖滩地植被平均单位面积生物量为3735.93g·m-2(鲜重);5)滩地植被单位面积生物量与Landsat-ETM+4亮度值间的回归方程为y=-4897.11+87.68x(式中y为生物量g·  相似文献   
365.
For an adequate analysis of pathological speech signals, a sizeable number of parameters is required, such as those related to jitter, shimmer and noise content. Often this kind of high-dimensional signal representation is difficult to understand, even for expert voice therapists and physicians. Data visualization of a high-dimensional dataset can provide a useful first step in its exploratory data analysis, facilitating an understanding about its underlying structure. In the present paper, eight dimensionality reduction techniques, both classical and recent, are compared on speech data containing normal and pathological speech. A qualitative analysis of their dimensionality reduction capabilities is presented. The transformed data are also quantitatively evaluated, using classifiers, and it is found that it may be advantageous to perform the classification process on the transformed data, rather than on the original. These qualitative and quantitative analyses allow us to conclude that a nonlinear, supervised method, called kernel local Fisher discriminant analysis is superior for dimensionality reduction in the actual context.  相似文献   
366.
A. Herbert 《Cytopathology》2000,11(6):471-479
Opinions about cervical screening in the UK tend to follow one of two negative lines of thought. The first is that cervical cancer is a rare disease, and too much time and effort are spent on screening. The second is that it has been relatively ineffective, since incidence of invasive carcinoma did not fall until the NHS Cervical Screening Programme (NHSCSP) was introduced in 1988, although it fell by 40% since then. This paper presents publicly available data to demonstrate that neither of these views is true. Registrations of invasive carcinoma of the uterine cervix and carcinoma in situ in England and Wales between 1971 and 1996 show that a substantially increased risk of disease in women born since 1940 has been reversed, almost certainly by greatly improved screening. Cervical carcinoma is now a rare disease because most cases are prevented before they become invasive, mostly by screening young women, aged 20-40, before the decade of life when symptomatic cervical carcinoma most frequently presents.  相似文献   
367.
368.
固定对组织光学性质的影响   总被引:2,自引:0,他引:2  
利用带有积分球的SHIMADZU UV—240分光光度计,测量了组织在固定前和后的反射率和透射率,分析了福尔马林固定对组织光学性质的影响。  相似文献   
369.
ObjectiveThe role of alternate sequential administration of sunitinib and capecitabine/temozolomide (CAPTEM) in metastatic pancreatic neuroendocrine tumors (PanNETs) remains unexplored. We thus aimed to analyze the efficacy and tolerability of this strategy in advanced grade 1/grade 2 PanNETs.MethodsIn total, data of 43 patients with metastatic PanNET were collected from a real-world database of a cancer center. Twenty-four patients were treated with sunitinib followed by CAPTEM (group 1), and 19 patients were treated with CAPTEM followed by sunitinib (group 2).ResultsTwenty-three patients were treated with first-line sunitinib or CAPTEM, and 20 patients were pretreated with somatostatin analog (SSA) or SSA in combination with transcatheter arterial chemoembolization. The objective response rate with first-line treatment was similar in both groups, whereas that with second-line treatment was higher in group 1 than in group 2, albeit with no significant differences (21.1% vs 5.3%, respectively; P = .205). Median progression-free survival (mPFS) for first-line and second-line treatments did not differ between the 2 groups (11 and 12 months vs 12 and 8 months, respectively). Following subgroup analyses, treatment with first-line sunitinib and sunitinib after pretreated SSA had a longer mPFS than that with second-line sunitinib after CAPTEM (11 months vs 8 months, respectively; P = .046), whereas treatment with first-line CAPTEM and CAPTEM after pretreated SSA had an mPFS similar to that of second-line CAPTEM after sunitinib treatment. CAPTEM and sunitinib had similar tolerability.ConclusionAlternating sunitinib and CAPTEM were well tolerated and associated with similar mPFS in grade 1/grade 2 PanNETs. However, larger prospective studies are required to investigate the efficacy of alternate sequential therapies for metastatic PanNET.  相似文献   
370.
Bixler  Harris J. 《Hydrobiologia》1996,326(1):35-57
Carrageenan has annual sales of over US$ 200 million, about 15% of the world use of food hydrocolloids. The market for carrageenan has grown exponentially at 5% per year for at least 25 years: 5 500 metric tons in 1970, and over 20 000 metric tons expected in 1995. The industry has become dominated by very large, multi-product companies with carrageenan factories in Europe and the US, but factories are now springing up in the Philippines and Chile, where red seaweeds grow in abundance. About 80 000 tons of dry red seaweeds are needed to produce 20 000 tons of carrageenan. About 40 000 tons comes from the Philippines, 15 000 tons from Indonesia, 15 000 tons from Chile, and 10 000 tons from elsewhere. Carrageenan growth depends on food fads like the McLean hamburger and food winners like processed pork and turkey. Carrageenan is a regulated food additive, and current health concerns focus on the minimum safe molecular weight for carrageenan when eaten. The most innovative development in carrageenans in recent years has been the introduction of a food grade version of lower cost natural grade carrageenan. Its acceptance, however, has been hampered by strong resistance from conventional carrageenan producers.  相似文献   
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