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61.
We evaluated long-term dynorphin A-immunoreactivity in the rat area postrema (AP) after the administration of cisplatin. First, rats were given 1, 5 and 10 mg/kg body weight cisplatin (i.p.) and their behavior was monitored for 72 h. We observed a delayed increase in pica 24-72 h after injection, compared to the 24 h before injection. We attributed this to the cisplatin injection. Pica was defined as an increase in the intake of non-nutritional matter such as kaolin. Administration of 1, 5 and 10 mg/kg cisplatin led to an increase in kaolin intake on day 1. Administration of 5 and 10 mg/kg of cisplatin led to decreased intake of laboratory chow (MF) on days 1–3, but 10 mg/kg cisplatin causes an excessive aggravation of their condition. Following this behavioral experiment, we immunohistochemically examined the induction of dynorphin A in the AP at 24, 48 and 72 h post-administration of 1 and 5 mg/kg cisplatin. Administration of 5 mg/kg cisplatin caused dynorphin A to accumulate gradually in the neurosoma of the AP neurons, and the numbers of positive AP neurosomata at 48 and 72 h post-administration were higher than following an equal dosage of 0.9% NaCl. These findings suggest that dynorphin A increases in the central nervous system for a long time following administration, and causes certain behavioral and clinical changes, including those related to appetite and nausea.  相似文献   
62.
In order to investigate whether mesangial transport by glomeruli is delayed in ddY mice pretreated with sheep anti type IV collagen serum, the mice were administered an overload of human IgA myeloma serum. Non pretreated ddY mice used as controls and both experimental and control BALB/c mice were also processed in a similar manner. The intensities of mesangial deposition of human IgA were examined periodically and were found to correlate well with deposition of mouse IgA. Both mouse and human IgAs showed a gradual increase for up to 8 experimental weeks. In the control young ddY mice, however, the overloaded mesangial human IgA quickly disappeared, presenting no appreciable mesangial deposition of autologous IgA. In sharp contrast, both the experimental and control BALB/c mice showed an initially prolonged and rather heavy mesangial deposition of human IgA, followed by a gradual decrease and somewhat light mesangial deposition of autologous mouse IgA. These results obtained using experimental ddY mice appear to confirm the possibility that non immunological local trapping, due to retardation of mesangial transport function, causes mesangial deposition of autologous mouse IgA in this particular strain. Acta Pathol Jpn 39: 289 295, 1989.  相似文献   
63.
Publication bias in reproductive research   总被引:3,自引:0,他引:3  
Publication bias is defined as any tendency on the part of investigators or editors to fail to publish study results on the basis of the direction or strength of the findings. This may lead to overestimation of treatment effects in published work. Inappropriate decisions about patient management may result. We investigated what proportion of abstracts at the European Society of Human Reproduction and Embryology (ESHRE) annual meeting eventually reached full publication, what was the time to publication, and which factors might have affected publication. Among the 2691 abstracts of six ESHRE annual meetings, 151 (5.6%) reporting randomized controlled trials (RCT) were identified. Comprehensive searches of electronic databases and handsearching of the two major journals in the field yielded 79 full publications pertaining to these abstracts. Kaplan-Meier analysis estimated 56% of RCT abstracts to be eventually published in full, the median time to publication being 32.5 months. Positive outcome (i.e. significant results) did not affect the publication rate, and neither did sample size, the subject category, or the native language (English/non-English) of the country of origin. Oral presentations resulted in eventual full publication significantly more frequently (69%) than posters (42%). It is concluded that a considerable publication deficit, but not a publication bias, exists for RCT in reproductive research.  相似文献   
64.
Rats were permanently hypodipsic when offered a quinine adulterated fluid on a chronic basis. Plasma osmolarity and Na concentration were normal, but the quinine drinkers showed a slight hyperkalemia compared to water drinking controls. The quinine-drinking rats maintained hydromineral equilibrium through the excretion of a small amount of concentrated urine. The quinine intake was closely matched to need, and fell to near zero when food was removed or water was supplied intravenously. This harmony of intake and output was disrupted after acute hypertonic NaCl load: while the obligatory salt diuresis was no different between water and quinine drinkers, the latter did not drink (except at the lowest level of adulteration) within several hours. However, by 24 hr all had shown a delayed drinking response. This delay in drinking of quinine was also evident after non-painful intravenous NaCl infusions, but no drinking occurred after nephrectomy. Quinine drinkers were also unresponsive to isoproterenol and intracranial dipsogens. These data are discussed in terms of their implication for definitions of regulatory drinking behavior.  相似文献   
65.
骨骼畸形儿童的临床研究   总被引:1,自引:0,他引:1  
目的探讨骨骼畸形与晚发性佝偻病(DR)的关系.方法采用病例对照,结合临床调查,检测了85例骨骼畸形儿童及50例健康儿童的血钙、血磷、碱性磷酸酶(ALP)、骨碱性磷酸酶(BALP)、X线.结果85例5~16岁骨骼畸形儿童的临床症状主要为多汗、肢体疼痛、肢体无力、肌肉痉挛;体征以鸡胸和X形腿为多见;血钙、血磷、碱性磷酸酶检测阳性率均低,BALP测定阳性率(BALP>250U/L)为14.1%,诊断为DR,并与对照组比较,差异有显著性意义(p<0.05).结论要重视骨骼畸形儿童的诊断及DR的诊断和防治工作.  相似文献   
66.
Delayed pressure urticaria (DPU) is a poorly understood syndrome. We describe 17 patients with DPU. Chronic urticaria was present in 94%. All had negative challenges for immediate demographism and cold urticaria. DPU was induced with a pressure challenge on the shoulder of 15 pounds for 15 min. Average onset of pressure lesions after challenge was 6.5. Lesions were painful, not pruritic, peaked at 9 hr, and disappeared by 24 to 48 hr. Fever, chills, and/or arthralgias occurred in 78%. Positive laboratory abnormalities included leukocytosis in 20% and elevated erythrocyte sedimentation rate in 37.5%. Skin biopsies of lesions showed perivascular round cell infiltrates and negative immunofluorescence. Urticaria responded to antihistamines, but not aspirin, in 100% of patients, while pressure lesions improved with nonsteroidal anti-inflammatory drugs (NSAID), but not antihistamines, in 80% of patients. Both urticaria and DPU were controlled with prednisone, which was necessary in 87.5% of patients. A severe nonremitting course was noted in 7%, 40% had a moderate remitting course requiring intermittent prednisone, and 53% had a mild remitting disease requiring no medication or antihistamines and/or NSAID only. We conclude that DPU is more common than previously appreciated and likely involves mediators other than histamine, possibly the prostaglandin system.  相似文献   
67.
Summary A specific 6-keto-prostaglandin PGI2 radioimmunoassay (R.I.A.) was used to follow tissue prostacyclin formation in a series of acute and delayed pig flaps. Each flap measured 12×5 cm and four white, female ehester pigs, averaging 21 kgs in weight, were used. Flap tissue samples were taken at day 0 (control) 1–8, 10, 14, 17 and 21 using 0.4 mm diameter cork borer. Prostacyclin formation started to rise on day 4 and extended until the 10th day in both types of flaps. The hyperemic circulation that occurred following delay procedure is associated with a rise in prostacyclin production whereas the higher rise in prostacyclin in the undelayed flap is due to the reactive inflammation.  相似文献   
68.
(1) Background: Labeling is one of the significant strategies to guide sustainable consumption behaviors. Nowadays, multi labels being displayed on the front-of-pack of food products is a common phenomenon. However, labels seldom operate solo, and competition or complement effects may be exerted on different labels. Therefore, the research objective is to explore the interaction effect when nutrition and low-carbon labels appear simultaneously; (2) Methods: Across four scenario-based experiments, including ice cream, yogurt, steak, and toast, this study manipulated the separate and joint occurrences of low-carbon and nutrition labels, the interaction effect of joint labels was tested, and the serial mediation model, which includes resource allocation and anticipated enjoyment of food consumption, was verified; (3) Results: Results show that people have a positive preference for the nutrition label and the carbon label, respectively, while these two labels working simultaneously attenuate the positive effect of the single label. When facing nutrition and carbon labels simultaneously, people would infer partial resources are allocated to healthy and environmental aspects so they have a lower anticipated enjoyment from food consumption. Thus, these two labels working simultaneously attenuate the positive effect of the single label, and consumers have a lower evaluation of food products. In addition, the joint backfire on the effect is only exerted on people with a higher level of zero-sum bias and only when joint labels have a high consistency of labels; (4) Conclusions: This study solved the contradictory problem of the joint effect of positive labels. The findings in this research contribute to promote sustainable food consumption. We suggest that similar labels should be avoided in the same front-of-pack of food, and manufacturers need to use ads to bring down consumers’ zero-sum bias.  相似文献   
69.
《Value in health》2021,24(8):1137-1144
ObjectivesPopulation-adjusted comparisons of progression-free survival (PFS) from single-arm trials of cancer treatments can be derived using matching-adjusted indirect comparisons (MAICs); however, results are still susceptible to bias, particularly if the trials had different tumor assessment schedules. This study aims to assess the effects of assessment-schedule matching (ASM) on the relative effectiveness on the PFS of avelumab versus approved comparator immunotherapies or chemotherapy after population matching in the second-line (2L) setting for metastatic urothelial carcinoma.MethodsThe MAIC used patient-level data for avelumab from the JAVELIN Solid Tumor trial (NCT01772004). PFS was compared with published curves for other treatments to obtain population-adjusted hazard ratios (HRs). The MAIC was repeated after conducting ASM for differences in tumor assessment scheduled first at 6 weeks for avelumab and durvalumab and at 8 or 9 weeks for other treatments.ResultsMAIC adjustment alone altered the HR estimates up to 23%, whereas MAIC plus ASM resulted in up to 32.7% reductions from naive comparisons. Even in cases in which MAIC had little effect, ASM brought an additional change of 11.1% to 15.4%. Overall, the HR range of avelumab versus other treatments changed from 0.83 to 1.25 for naive comparisons to 0.76 to 0.99 after ASM plus MAIC, numerically favoring avelumab.ConclusionsSmall variations in assessment schedules can introduce bias in unanchored indirect treatment comparisons of interval-censored time-to-event outcomes. In this study, adjusted PFS was comparable across second-line urothelial carcinoma treatment options, numerically favoring avelumab versus immunotherapies and chemotherapy agents. Correcting this bias is especially important when HRs are applied in cost-effectiveness models to transition patients between states.  相似文献   
70.
目的探讨重症先天性膈疝(CDH)患儿的临床治疗策略。 方法选择2015年1月至2019年10月,西北妇女儿童医院小儿外科收治的7例重症CDH患儿为研究对象。采用回顾性研究方法收集受试儿一般临床资料、治疗、转归及术后随访结果等进行分析。本研究遵循的程序符合2013年新修订的《世界医学协会赫尔辛基宣言》要求。 结果本组7例重症CDH患儿临床资料分析结果如下。①一般临床资料:7例患儿中,男、女性患儿分别为4例(No.2、5~7)与3例(No.1、3~4);1例(No.4)为足月单纯低出生体重儿,1例(No.7)为足月低出生体重合并多系统畸形儿,5例(No.1~3、5~6)为低出生体重早产儿;2例(No.2、7)为采取辅助生殖技术出生婴儿,均合并染色体异常。娩出方式:5例(No.1~4、7)经剖宫产术娩出,2例(No.5~6)自然分娩。4例孕母(No.1~2、6~7)有流产史。②治疗情况:除No.6患儿出生后1、5、10 min Apgar评分均为10分外,其余6例在手术室或产房采取气管插管、高频振荡通气(HFOV)、禁食、胃肠减压治疗。No.1患儿因合并多发复杂畸形,患儿家属放弃手术治疗,3例(No.4~6)经左侧胸后外侧切口入路手术,3例(No.2~3、7)经左上腹切口入路手术进行CDH修补术。③转归:1例(No.1)术前放弃治疗后死亡,3例(No.3~4、7)术后死亡。这4例死亡患儿中,除No.4患儿外,No.1、3、7患儿均合并复杂先天性心脏病及其他系统畸形。3例(No.2、5~6)患儿采取手术治疗后治愈出院,均合并早产、低出生体重、其他非复杂畸形。对这3例痊愈患儿术后随访结果显示,1例(No.2)术后1个月CDH复发,经再次CDH修补术治疗后,膈肌完整,截至随访时未见复发;No.5~6患儿截至随访时,均生长发育良好。 结论合并复杂先天性心脏病,可能是影响重症CDH患儿预后的主要因素之一。对重症CDH患儿娩出后采取即时气管插管、HFOV、延迟手术修复(DSR)等治疗策略,有助于提高该病患儿手术治愈率。  相似文献   
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