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31.
Interaction of human low-density lipoproteins (LDL) with discoidal complexes comprised of egg yolk phosphatidylcholine and human apolipoprotein A-I (molar ratio, 88:1, respectively) was investigated. The multicomponent gradient gel electrophoretic pattern of LDL is transformed to one that includes a predominant component with an apparent particle diameter larger than that of the initial major LDL but still in the size range of normal LDL. The apparent particle diameter increase (range, 0.2-3.5 nm) is proportional to the increase (range, 6-40%) in LDL phospholipid/protein weight ratio following incubation (37 degrees C; 6 and 24 h); the smaller the initial LDL diameter, the greater the apparent particle diameter increase and percentage of phospholipid uptake. The LDL unesterified cholesterol/protein weight ratio decreases (range, 33-39%), but does not correlate with the increase in apparent particle diameter value. Interaction products are round particles with intact apolipoprotein B and show no evidence of phospholipid degradation. The products appear more dense than expected from the size vs. density relationship observed for nonincubated LDL subspecies. In addition to products in the normal LDL size range, larger components (apparent particle diameter range, 29.0-41.2 nm) also form and may be association complexes of phospholipid-modified LDL. Our results indicate that phospholipid uptake by LDL may contribute to the particle size polydispersity observed in plasma LDL.  相似文献   
32.
The present study was carried out to investigate the impact of climate change on land suitability for agricultural development in a sub-basin of Karkheh River Basin, Iran. For this, land suitability of the sub-basin was evaluated twice; once regardless of the climate change impact, and again by involving the impact of climate change. Simple Limitation Approach was used to evaluate the suitability of the sub-basin for cultivation of winter wheat. According to the results, around 22.57% (124121.16 ha) of the study area is suitable for cropping while the capability of 39.29% (216086.13 ha) of the sub-basin was evaluated to be poor/moderate for this purpose. In this research, in order to investigate the impact of climate change on farmlands, the changing trend of the four variables of maximum and minimum temperature, precipitation, and radiation were stimulated by the year 2039 using downscaled interpolation of IPCM general circulation model under three emission scenarios of A1B, A2, and B1. The stimulation was done by LARS-WG Software. The overlaying was done once more, but this time using the stimulated values. Comparing the current and stimulated land suitability maps revealed the fact that, in the most pessimistic future under A1B scenario, approximately 15.51% (85288.95 ha) of the study area will lose its capability for farming as a result of an increase of 1.3?C in temperature, and a decrease of 20.43% mm in total precipitation. The research finding emphasizes the risk of climate change on land health for farming purposes.  相似文献   
33.

Objectives

Assessing the value of the Combined-Apgar score in predicting neonatal mortality and morbidity compared to the Conventional-Apgar.

Methods

This prospective cohort study evaluated 942 neonates (166 very preterm, 233 near term, and 543 term) admitted to a tertiary referral hospital. At 1- and 5-minutes after delivery, the Conventional and Combined Apgar scores were recorded. The neonates were followed, and the following information was recorded: the occurrence of severe hyperbilirubinemia requiring medical intervention, the requirement for mechanical ventilation, the occurrence of intraventricular hemorrhage (IVH), and neonatal mortality.

Results

Before adjusting for the potential confounders, a low Conventional (<7) or Combined (<10) Apgar score at 5-minutes was associated with adverse neonatal outcomes. However, after adjustment for the gestational age, birth weight and the requirement for neonatal resuscitation in the delivery room, a depressed 5-minute Conventional-Apgar score lost its significant associations with all the measured adverse outcomes; after the adjustments, a low 5-minute Combined-Apgar score remained significantly associated with the requirement for mechanical ventilation (OR,18.61; 95%CI,6.75–51.29), IVH (OR,4.8; 95%CI,1.91–12.01), and neonatal mortality (OR,20.22; 95%CI,4.22–96.88). Additionally, using Receiver Operating Characteristics (ROC) curves, the area under the curve was higher for the Combined-Apgar than the Conventional-Apgar for the prediction of neonatal mortality and the measured morbidities among all the admitted neonates and their gestational age subgroups.

Conclusions

The newly proposed Combined-Apgar score can be a good predictor of neonatal mortality and morbidity in the admitted neonates, regardless of their gestational age and resuscitation status. It is also superior to the Conventional-Apgar in predicting adverse neonatal outcomes in very preterm, near term and term neonates.  相似文献   
34.
Genetica - This study aimed to investigate the effects of incidence rate, heritability, and polygenic variance on the statistical power of genome-wide association studies (GWAS) for threshold...  相似文献   
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Multiple Sclerosis (MS) is a multifocal demyelinating central nervous system disorder in which interplay between genes and the environment are supposed to be involved. Mitochondrial DNA (mtDNA) has the only non-coding regions at the displacement loop (D-loop) region that contains two hypervariable segments (HVS-I and HVS-II) with high polymorphism. mtDNA has already been fully sequenced and many subsequent publications have showed polymorphic sites, haplogroups and haplotypes. Haplogroups could have important implications to understand association between mutability of the mitochondrial genome and disease. To assess relationship between mtDNA haplogroups and MS, we have sequenced the mtDNA HVS-I in 54 MS patients and 100 control subjects. We have found that haplogroups A and K are significantly more abundant in MS patients (P=0.042 for haplogroup A and P=0.0005 for haplogroup K). Thus, these two haplogroups might act synergistically to increase the penetrance of MS disease.  相似文献   
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In 1997, autologous sural nerve grafting to reconstruct bilaterally resected cavernosal nerves was successfully performed in patients undergoing radical retropubic prostatectomy. After 12 months, one third of these patients had erections sufficient for intercourse. Since that time, patients who have had neurovascular bundle resection and sural nerve grafting have continued to show promising results. For example, within one large cohort of men who had unilateral, nerve-sparing radical prostatectomy, significantly more men who had sural nerve grafting regained potency, and did so in less time, than men who did not have grafting. More importantly, however, with better predictions of the presence of extracapsular disease, nerve-sparing surgery can be performed more selectively, reserving wide resection and sural nerve grafting for patients likely to have extracapsular extension. A multicenter, randomized clinical trial is needed to substantiate the positive outcomes observed with sural nerve grafting.  相似文献   
39.
Transitional cell carcinoma (TCC) of the bladder typically metastasizes to the pelvic lymph nodes and to visceral sites including the lungs, liver, and bones. Other sites include the brain, especially after systemic chemotherapy. To our knowledge, we report the first case of TCC metastatic to the soft tissue of the shoulder girdle and discuss common and unusual sites of metastasis in TCC.  相似文献   
40.
Baseline or acquired resistance to docetaxel (DOC) represents a significant risk for patients with metastatic prostate cancer (PC). In the last years, novel therapy regimens have been approved providing reasonable alternatives for DOC‐resistant patients making prediction of DOC resistance of great clinical importance. We aimed to identify serum biomarkers, which are able to select patients who will not benefit from DOC treatment. DOC‐resistant PC3‐DR and DU145‐DR sublines and their sensitive parental cell lines (DU145, PC3) were comparatively analyzed using liquid chromatography‐coupled tandem mass spectrometry (LC‐MS/MS). Results were filtered using bioinformatics approaches to identify promising serum biomarkers. Serum levels of five proteins were determined in serum samples of 66 DOC‐treated metastatic castration‐resistant PC patients (mCRPC) using ELISA. Results were correlated with clinicopathological and survival data. CD44 was subjected to further functional cell culture analyses. We found at least 177 two‐fold significantly overexpressed proteins in DOC‐resistant cell lines. Our bioinformatics method suggested 11/177 proteins to be secreted into the serum. We determined serum levels of five (CD44, MET, GSN, IL13RA2 and LNPEP) proteins in serum samples of DOC‐treated patients and found high CD44 serum levels to be independently associated with poor overall survival (= 0.001). In accordance, silencing of CD44 in DU145‐DR cells resulted in re‐sensitization to DOC. In conclusion, high serum CD44 levels may help identify DOC‐resistant patients and may thereby help optimize clinical decision‐making regarding type and timing of therapy for mCRPC patients. In addition, our in vitro results imply the possible functional involvement of CD44 in DOC resistance.  相似文献   
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