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51.
Divided attention effects have been observed across a variety of stimuli and perceptual tasks, which have given rise to both object-based and space-based theories of divided attention. Object-based theories assert that processing information from multiple objects is limited, whereas space-based theories assert that processing information from multiple locations is limited. Extant results in the literature are collectively inconsistent with both simple object-based theories and simple space-based theories of divided attention. Using a visual search task with the extended simultaneous-sequential method to reveal capacity limitations, we found evidence of limited-capacity processing of object properties and unlimited-capacity processing of feature contrast. We found no evidence of a separate spatial limitation. A multiple pathway processing theory can account for these and a large body of previous results. According to this theory, tasks that require object processing must follow a limited-capacity pathway and therefore incur divided attention effects. Tasks that depend on only feature contrast can follow a separate unlimited-capacity processing pathway and therefore do not incur divided attention effects.  相似文献   
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目的观察顺铂等灌注和恩度治疗恶性胸腹积液的临床疗效及安全性。方法 62例晚期恶性胸腹水患者,治疗组32例,胸/腹腔内灌注恩度和化疗药物DDP/5-FU,对照组30例,仅灌注化疗药物DDP/5-FU,均3次/周,连续4周为一疗程,休息4周后,评价疗效及不良反应。结果治疗组中12例CR,16例PR,3例SD,1例PD,有效率为87.5%;对照组6例CR,13例PR,7例SD,4例PD,有效率为63.3%,两组比较差异有统计学意义(P〈0.05),不良反应发生率两组比较无统计学意义(P〉0.05)。结论顺铂等加恩度灌注治疗恶性胸腹腔积液有较好的疗效和安全性,并有效提高了晚期肿瘤患者的生活质量,值得临床进一步推广应用。  相似文献   
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糖脂代谢是人体生命活动中重要的物质代谢过程,其合成代谢与分解代谢的相互协调确保正常的生理功能。阴阳学说中“阳化气”“阴成形”的理论是对机体生命规律及物质与能量关系的生动描述。抑胃肽(GIP)和胰高血糖素样肽1(GLP-1)作为2种主要的肠促胰素,由肠道内分泌细胞产生,作用于胰腺、脑、肝脏等组织,合成与分解饮食中的糖类与脂质,为机体提供能量并存储能量。其中,GIP刺激白色脂肪,促进脂质储存,具有类似于“阴成形”的作用,GLP-1刺激棕色脂肪,增加产热,具有类似于“阳化气”的作用,二者之间还有对立制约、互根互用、消长平衡的阴阳关系。GIP与GLP-1的关系与机体糖脂代谢的生理、病理学密切相关。糖脂代谢紊乱早期均以瘀滞状态为主,糖尿病以阳盛阴病为主,而肥胖症以阴盛阳病为主。调整阴阳可改善糖脂代谢紊乱状态,现代医学研究表明,共同激动GIP与GLP-1,会产生更好地控制血糖、体质量的效果。本文借助中医阴阳理论,以肠促胰素为切入点,浅析GIP与GLP-1在糖脂代谢中的作用关系,以丰富中医药对糖尿病、肥胖症等代谢疾病的研究思路。  相似文献   
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Purpose:This study was conducted to ensure the integrity of surgery wounds.Methods:This was a randomized prospective trial of 300 patients who underwent small-incision cataract surgery (SICS) at our hospital over a one-year period. We used 2–3 drops of 5% povidone-iodine at the end of each case, not only to disclose any wound leaks but also to sterilize the surface of the eye.Results:Three hundred patients underwent SICS. One hundred ten patients had postoperative wound leak in SICS due to surgical complications. Premature entry comprising 75% (83 cases), followed by floppy iris syndrome comprising 20% (22 cases) and 5% (6 cases) comprising pseudoexfoliation (PXF) syndrome. There was a drop in the number of re-surgeries from 12 to 3 cases since we started implementing this technique.Conclusion:The simple procedure is very handy and economical in identifying the leak and can reduce further complications such as endophthalmitis and re-surgeries. Among residents, this can be a boon where povidone-iodine acts as a riverbank for the outflow of aqueous, outlining the speed, location, and quantity of the leak. Siep’s test plays an important role in identifying any postoperative wound leaks and also sterilizing the eye surface post surgery.  相似文献   
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In the present study, the root nodules of Premna herbacea Roxb. (PH) was investigated for its in vitro cytotoxicity and in vivo antitumor activity. Two extracts, aqueous and alcoholic; two fractions of alcoholic extract, ethyl acetate and butanol fractions were screened for their in vitro cytotoxicity by brine shrimp lethality (BSL) assay, trypan blue exclusion assay and MTT assay. Alcoholic extract and its ethyl acetate fraction were found to be the most effective in BSL assay, trypan blue exclusion assay. In vivo antitumor activity was screened in the Ehrlich ascites carcinoma (EAC) model and the Dalton lymphoma ascites (DLA) model. The extracts and the fractions were tested at two dosages (250 and 500 mg/kg) by intraperitoneally (i.p.) route on every alternate day upto 13th day. Cisplatin was used as positive control in both studies in single dose (day 1) 3.5 mg/kg by i.p. route. In EAC model, ascites tumor was induced by inoculating 2.5 million of EAC cells i.p. alcoholic extract at 500 mg/kg was the most effective in elevating MST, reduction in body weight in EAC induced tumor. Only the effective extract i.e., alcoholic extract were studied for hematological and antioxidant parameter. It showed a restoring effect on altered hematological parameters and a significant improvement in biochemical parameters at 250 mg/kg dose of alcoholic extract. These results explain the toxicity of 500 mg/kg might be high. In the Dalton lymphoma ascites (DLA) model, solid tumor was developed by i.m. injection of 1 million DLA cells. Both the extracts and the fractions possessed potent antitumor activity against solid tumor models by significantly reducing the solid tumor weight and volume.  相似文献   
59.
Perforative peritonitis is the most common surgical emergency in general surgical practice. Gastrointestinal perforation is the etiology in the vast majority of the patients. However, occasionally, other rare causes may be encountered. One such cause of peritonitis is spontaneous perforation of non-gravid uterus. Uterine perforation is a potential complication of any intrauterine procedure and may be associated with injury to surrounding blood vessels or viscera such as the urinary bladder or intestine. Spontaneous uterine perforation is rare and less than 50 cases have been reported in the English literature. We are presenting two such cases of spontaneous perforation of the uterus in elderly postmenopausal women which presented with generalized peritonitis and were clinically indistinguishable from gastrointestinal perforation.  相似文献   
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