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301.
Russian Journal of Bioorganic Chemistry - New Furan, 1,3,4-thiadiazole and 1,2,4-triazole hybrid compounds and their 1,3,4-oxadiazole hybrid derivatives were synthesized. The thioglycoside...  相似文献   
302.
Background and aimGastric Cancer (GC) is a leading cause of morbidity and mortality worldwide, particularly in developing nations, only a few suitable gastric cancer serum biomarkers with acceptable sensitivity and specificity exist. This work aims to highlight and uncover miR-30a-5p and miR-182–5p′s diagnostic roles regarding gastric cancer and their roles in predicting prognosis.Methods148 patients participated in this study. Groups I, II, and III had 47 patients with GC, 54 patients with benign gastric lesions, and 47 apparently healthy subjects of coincided age and gender as controls, respectively. All participants were clinically evaluated and subjected to CBC, serum CEA, and CA19-9 by ELISA, and real-time PCR tests of miR-30a-5p and miR-182–5p.ResultsMiR30a-5p and miR-182–5p were down regulated in gastric cancer patients in Group I more than Groups II and III (P < 0.001). ROC curve analysis revealed that miR30a-5p had better AUC, sensitivity, and specificity (0.961%, 93.62%, and 90.74%respectively). When miR-182–5p was gathered with CEA and CA19-9, specificity raised to 98.15% and PPV to 97.6%. Lower miR-30a-5p levels are linked with the presence of distant metastases, advanced TNM stage, and degree of pathological differentiation of tumors in GC patients (p = 0.034, 0.019, 0.049) respectively. According to the multivariate analysis, miR30a-5p expression level could be an independent predictor of GC.ConclusionOur results exhibited that miRNAs, miR-30a-5p and miR182–5p, gene expression have a diagnostic power and can identify patients with GC. MiR-30a-5p displayed the highest diagnostic specificity and sensitivity. Besides other known tumor markers, they could offer simple noninvasive biomarkers that predict gastric cancer.  相似文献   
303.
Due to the better solubility of the 4,4′-substituted bipyridine ligand a series of 4,4′-bis(tert-butyl)-2,2′-bipyridinedichlorometal(II) complexes, [M(tbbpy)Cl2], with M = Cu, Ni, Zn, Pd, Pt was synthesised and characterised. The blue copper complex 4,4′-bis(tert-butyl)-2,2′-bipyridinedichlorocopper(II) was isolated in two different polymorphic forms, as prisms 1 with a solvent inclusion and solvent-free as needles 2. Both structures were determined by X-ray structure analysis. They crystallise in the monoclinic space group P21/c with four molecules in the unit cell, but with different unit cells and packing motifs. Whereas in the prisms 1, with the unit cell parameters a = 12.1613(12), b = 10.6363(7), c = 16.3074(15) Å, β = 94.446(8)°, the packing is dominated by intra- and intermolecular hydrogen bonds, in the needles 2, with a = 7.738(1), b = 18. 333(2), c = 13.291(3) Å, β = 97.512(15)°, only intramolecular hydrogen bonds appear and the complex molecules are arranged in columns which are stabilised by π-π-stacking interactions. In both complexes the copper has a tetrahedrally distorted coordination sphere. These copper complexes were also studied by EPR spectroscopy in solution, as frozen glass and diamagnetically diluted powder with the analogue [Pd(tbbpy)Cl2] as host lattice.  相似文献   
304.

Background

Prolonged wound-discharge following total hip arthroplasty (THA) is associated with an increased risk of infection. However, the potential role of hypertension in prolonging the duration of wound healing in this population has not yet been investigated. The aim of the present study was to compare healing in this population that has not yet been investigated. The aim of the present study was to compare hypertensive and normotensive THA patients in terms of the length of time required to achieve a dry wound and the length of stay in the hospital.

Methods

One hundred and twenty primary THA patients were evaluated. Pre-operative clinical history and physical examination revealed that 29 were hypertensive and 91 were normotensive. The two groups were statistically matched using optimal propensity score matching. The outcomes of interest were the number of days until a dry wound was observed and the duration of hospital stay.

Results

The average systolic blood pressures were 150.1 mmHg and 120.3 mmHg for the hypertensive and normotensive groups, respectively. The mean number of days until the wound was dry was 3.79 for the hypertensive group and 2.03 for the normotensive group. Hypertensive patients required more days for their wounds to dry than normotensive patients (odds ratio  = 1.65, p<0.05). No significant difference in the duration of hospital stay was found between the two groups.

Conclusions

Hypertensive patients had a higher risk of prolonged wound discharge after THA than their normotensive counterparts. Patients with prolonged wound drainage are at greater risk for infection. Clinicians should pay particular attention to infection-prevention strategies in hypertensive THA patients.  相似文献   
305.
Attention deficit hyperactivity disorder (ADHD) is one of the most common childhood behavioral disorders characterized by inattention, hyperactivity and impulsivity. In Saudi Arabia the prevalence of combined ADHD is 16.4?%. ADHD etiology is not clear and not completely understood. There are several evidences for involvement of dopaminergic, serotonergic and noradrenergic neurotransmitter systems in the pathogenesis of ADHD. Monoamine Oxidase A (MAOA) is involved in the degradation of all three of these neurotransmitters. Dopamine Transporter 1 (DAT1) plays an important role in controlling blood levels of dopamine. The aim of the present study is to investigate the association between ADHD and polymorphisms of MAOA 30?bp-promoter VNTR and DAT1 40?bp 3′ UTRVNTR in Saudi population. PCR technique was employed to detect polymorphisms of MAOA and DAT1 genes in a sample of 120 ADHD subjects and 160 controls. Alleles and genotypes frequencies for both of MAOA and DAT1 polymorphisms were compared among ADHD subjects against controls. Association between ADHD and alleles as well as genotypes for each studied polymorphisms was tested by odds ratio (OR) test and the magnitude of this association was estimated by 95?% confidence interval (95?% CI). A significant association was found between two MAOA genotypes 3/4 and 3/2 with ADHD (P?<?0.01, OR?=?3, 4.9) as a risk effect. No significant association was found with MAOA alleles. Among DAT1 polymorphisms two alleles (7 and 11 repeats) (P?<?0.01, OR?=?2.5 and 3.3) as well as two genotypes (11/11 and 11/7) (P?<?0.01, OR?=?4, 3) showed significant association with ADHD as a risk effect. On the contrary, 9 and 10 repeats revealed significant association as a protective effect as well as 10/10 and 10/9 genotypes. These findings support the hypothesis that some of the MAOA and DAT1 polymorphisms have a causative role in the development of ADHD in the Saudi population. Another polymorphism did not give rise to support this hypothesis. This is the first report investigated the association between MAOA and DAT1 polymorphism at molecular level in Saudi Arabia population as well as Arab world. Therefore further studies are needed to generalize obtained results at Saudi Arabia.  相似文献   
306.
307.
Loratadine is a class II water-insoluble drug and its dissolution rate and, consequently, absorption are dependent on the gastrointestinal pH. The resulting very high variability in bioavailability and related inter- and intra-subject absorption variations present a major challenge that hinders the realization of an effective and uniform therapy. Among the several techniques that have been used to minimize pH dependency of dissolution rate, liquisolid compacts technique can be suggested as a promising solution. In this study, it was hypothesized that the formulation of loratadine using liquisolid compacts technique may reduce the effect of pH variation on the drug dissolution rate. Solubilities of loratadine in propylene glycol, Tween 80, and polyethylene glycol 400 were first measured and propylene glycol was selected as for producing the highest solubility among the tested solvents. Several liquisolid tablet formulations containing various ratios of drug: propylene glycol (5%, 10%, and 20% w/w) were prepared. The ratio of microcrystalline cellulose (carrier) to silica (coating powder material) was kept constant in all formulations. The dissolution behavior of loratadine from liquisolid compacts was investigated in several buffered media with different pH values (pH 1.2, 2.5, and 5). The results showed that the drug release rates produced by liquisolid compacts were significantly higher and less affected by pH variation compared with conventionally made (direct compression) and commercial (Clarityn) tablets. In conclusion, liquisolid compacts technique may be used as a tool to minimize the effects of pH variation on the dissolution rate of drugs with poor water solubility.  相似文献   
308.
The genetic diversity of 13 local Palestinian fig genotypes was investigated using RAPD markers. Among the 30 tested primers, 28 revealed various banding patterns and 2 generated no polymorphic bands. In addition, 13 primers (46.4%) produced good amplification products with high intensity and pattern stability. A total of 94 DNA fragments (loci), separated by electrophoresis on agarose gel were detected, ranging in size from 190 to 1300 bp. Of these fragments, 72 (76.6%) were polymorphic and 22 (23.4%) were monomorphic. A minimum of three and a maximum of eight DNA fragments were obtained using (OPH-02 and OPT-10) as well as (OPA-13, OPA-18 and OPY-07) primers respectively. The maximum percentage of polymorphic markers was 100.0 (Z-5, Z-12, and OPT-10) and the minimum was 60.0 (OPH-02). Primers OPY-07 and OPA-13 revealed high collective resolving power (Rp) values with 4.640 and 4.760 respectively and therefore, they were the most useful RAPD primers to assess the genetic diversity in the Palestinian figs. Genetic distance matrix showed an average distance range from 0.186 to 0.559 with a mean of 0.373. Thus, the cultivars tested in this study were characterized by large divergence at the DNA level. To our knowledge, this is the first report using RAPD marker to assess genetic diversity of Palestinian figs.  相似文献   
309.
310.
The gastrointestinal tract is a dynamic ecosystem containing a complex microbial community. In this paper, the indigenous intestinal bacteria and the microbial fermentation profile particularly short chain fatty acids (SCFA), lactate, and ammonia concentrations are reviewed. The intestinal bacterial composition changes with age. The bacterial density of the small intestine increases with age and comprises of lactobacilli, streptococci, enterobacteria, fusobacteria and eubacteria. Strict anaerobes (anaerobic gram-positive cocci, Eubacterium spp., Clostridium spp., Lactobacillus spp., Fusobacterium spp. and Bacteroides) are predominating caecal bacteria in young broilers. Data from culture-based studies showed that bifidobacteria could not be isolated from young birds, but were recovered from four-week-old broilers. Caecal lactobacilli accounted for 1.5-24% of the caecal bacteria. Gene sequencing of caecal DNA extracts showed that the majority of bacteria belonged to Clostridiaceae. Intestinal bacterial community is influenced by the dietary ingredients, nutrient levels and physical structure of feed. SCFA and other metabolic products are affected by diet formulation and age. Additional studies are required to know the bacterial metabolic activities together with the community analysis of the intestinal bacteria. Feed composition and processing have great potential to influence the activities of intestinal bacteria towards a desired direction in order to support animal health, well-being and microbial safety of broiler meat.  相似文献   
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