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101.
102.
结合目前中国农业现状和智能化方面的先进技术,设计一个通过管路连接到灌溉系统的施肥机,通过控制肥水的EC/pH浓度和进入灌溉管道的肥水量来实现自动施肥,它能够执行较精确的施肥过程,预防肥液施用不足或过量现象产生。本文设计的智能施肥机采用西门子SV-200系列PLC作为控制器,监控软件选用VB。  相似文献   
103.
In this study, quantum dots (QDs) having the photophysical properties of brightness, photostability and narrow emission were synthesized. The electrospinning has been introduced to be a simple technique for generating ultrathin fibers. Herein, we have synthesized QDs and electrospun polyvinylacetate (PVAc) nanofibers having these strongly luminescing QDs particles. The size and morphology of QDs were recorded with transmission electron microscopy (TEM). The structural nanofiber webs have been discussed by scanning electron microscopy (SEM). And fluorescence properties of strongly luminescing QDs nanofibers were also discussed.  相似文献   
104.
105.
Drug-induced liver injury (DILI) is a significant threat to patient health and a major concern during drug development. Recently, multiple circulating microRNAs (miRNAs) have been reported to be potential biomarkers for DILI. To adapt and validate miRNAs for clinical use, we investigated the time-course changes in miR-122 expression levels in an acetaminophen-induced liver injury model in rats. In addition, miR-155 and miR-21 were evaluated as makers of inflammation and regeneration, respectively, to characterize liver status. Our results revealed that miR-122 is an early and sensitive biomarker of hepatocellular injury at a stage when alanine transaminase, aspartate transaminase, and total bilirubin were not detectable. However, no significant differences in the expression levels of other miRNAs (miR-155 and -21) were observed between treatment and vehicle groups. Collectively, these time-course changes in the expression levels of miRNAs may be useful as markers for clinical decision-making, in the diagnosis and treatment of DILI.  相似文献   
106.

Objective

To evaluate endotracheal tube intracuff pressure (Pcuff) changes over time and the effect of these changes on air leak pressure (Pleak).

Study design

Prospective experimental study.

Animals

A group of nine healthy adult Beagle dogs.

Methods

In part I, in vitro measurements of Pcuff were recorded for 1 hour in eight endotracheal tubes subjected to four treatments: room temperature without lubricant (RT0L), room temperature with lubricant (RTWL), body temperature without lubricant (BT0L), and body temperature with lubricant (BTWL). In part II, nine dogs were endotracheally intubated and Pleak was evaluated at Pcuff of 25 mmHg. Subsequently, Pcuff was reset to 25 mmHg (baseline) and Pcuff measurements were recorded every 5 minutes for 1 hour. Subsequently, a second Pleak measurement was recorded at the current Pcuff. The data were analyzed using Wilcoxon signed-rank test, repeated measures anova and Mann–Whitney U test.

Results

In part I, Pcuff differed significantly between the RT0L and RTWL treatments at 5–60 minutes, and between the BT0L and BTWL treatments at 5–35, 55 and 60 minutes (p < 0.05). In part II, compared with baseline pressures, mean Pcuff decreased to <18 mmHg at 10 minutes and significant decreases were recorded at 15–60 minutes (Pcuff range: 10.0 ± 4.9 to 13.4 ± 6.3 mmHg, mean ± standard deviation). Significant differences were observed between the first and second Pleak measurements (p = 0.034). Pleak decreased in six of nine dogs, was not changed in two dogs and increased in one dog.

Conclusions and clinical relevance

Significant decreases in Pcuff over time were measured. Pleak may decrease during anesthesia and increase the risk for silent pulmonary aspiration. The results indicate the need for testing Pcuff more than once, especially at 10 minutes after the onset of anesthesia.  相似文献   
107.
Glutamine metabolism is an important metabolic pathway for cancer cell survival, and there is a critical connection between tumour growth and glutamine metabolism. Because of their similarities, canine mammary carcinomas are useful for studying human breast cancer. Accordingly, we investigated the correlations between the expression of glutamine metabolism‐related proteins and the pathological features of canine mammary tumours. We performed immunohistochemical and western blot analysis of 39 mammary tumour tissues. In immunohistochemical analysis, the expression of glutaminase 1 (GLS1) in the epithelial region increased according to the histological grade (P < .005). In the stromal region, complex‐type tumours displayed significantly higher GLS1 intensity than simple‐type tumours. However, glutamate dehydrogenase expression did not show the same tendencies as GLS1. The western blot results were consistent with the immunohistochemical findings. These results suggest that the expression of GLS1 is correlates with clinicopathological factors in canine mammary tumours and shows a similar pattern to human breast cancer.  相似文献   
108.
Paddy and Water Environment - Reclaimed soil is known to have high salinity due to poor water permeability. Soil conditioner can improve the permeability of the ground by changing the composition...  相似文献   
109.
Atherosclerosis is a chronic inflammatory disease that is characterized by infiltration of mononuclear lymphocytes into the intima through the expression of adhesion molecules on the arterial wall. In the present study, we report the inhibitory effects of two diarylheptanoids, 5-O-methylhirsutanonol (1) and oregonin (2), isolated from the methanolic extracts of Alnus japonica leaves, on the expression of adhesion molecules in human umbilical vein endothelial cells (HUVECs). Compounds 1 and 2 inhibited tumor necrosis factor (TNF)-alpha-induced up-regulation of vascular cell adhesion molecule-1 (VCAM-1) and intercellular adhesion molecule-1 (ICAM-1), which also prevented adhesion of monocytes to HUVECs, and slightly suppressed the mRNA expression of the inflammation-associated gene interleukin-1beta (IL-1beta). A further study demonstrated the inhibitory effect of compound 1 on DNA-binding of nuclear factor kappaB (NF-kappaB) and on the phosphorylation and degradation of inhibitory factor kappaBalpha (IkappaBalpha) in TNF-alpha-stimulated HUVECs. These results indicate that compounds 1 and 2 may be useful in the prevention and treatment of atherosclerosis through attenuation of adhesion molecule expression by inhibition of NF-kappaB activation.  相似文献   
110.
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