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671.

Background:

Early detection is a key to survival for gastric cancer. Molecular markers such as miRNA (microRNA) can have great importance in the early diagnosis of gastric cancer. Expression of miR-21 and miR-221 are deregulated in many types of human cancers. This study aimed to investigate the differences in miRNA expression patterns within the Iranian population.

Methods:

Total RNA was extracted from gastric cancer tissues and adjacent non-cancerous tissues from 32 patients. Expression levels of miR-21 and miR-221 were detected by Real time RT-PCR using a specific primer, with 5s rRNA as the internal reference gene.

Results:

Our data showed that the expression levels of miR-21 and miR-221 in gastric cancer samples were significantly higher than in paired non-cancerous samples (P < 0.05). The receiver operating characteristic (ROC) analyses yielded the area under the curve (AUC) values of 80.30 for miR-21 and 93.30 for miR-221, and combined ROC analysis revealed the highest AUC value of 96.90 in discriminating GC patients from healthy controls.

Conclusion:

It seems that miR-21 and miR-221 expression pattern in Iranian patients with gastric cancer are similar to any other population. Considering the increased expression level of two miRNAs in cancerous tissue compared to normal tissue as well as the area under ROC curve, miR-21 and miR-221 can be used for early detection of gastric cancer. Key Words: MicroRNAs, Tumor markers, Stomach neoplasms  相似文献   
672.
Producing higher yields under organic conditions is generally hampered by weeds and lesser nutrient supply. In wheat certain adaptive traits like early season vigour, taller plants, and shorter life cycle have been reported to help plants compete with weeds and produce satisfactory yields. In this experiment we tested the hypothesis ‘that early flowering and maturity conferred by insensitive vernalization alleles Vrn-A1a and/or Vrn-B1 has a yield advantage under organic conditions’ in Canadian spring wheat germplasm. We genotyped 32 cultivars for their vernalization gene composition (Vrn-A1a, Vrn-B1 and Vrn-D1) and studied these cultivars in organic and conventional management systems. We found 88 % of the cultivars possessed vernalization (Vrn) insensitive allele Vrn-A1a either alone or in combination with Vrn-B1. There were no differential affects between the cultivars having insensitive Vrn allele at either single locus (Vrn-A1a) or two (Vrn-A1a, Vrn-B1) under organic and conventional field conditions; except for days to maturity, where cultivars having only Vrn-A1a allele matured earlier. This earlier maturity did not translate to any yield advantage under organic field conditions. Overall, the cultivars grown under organic conditions were earlier flowering, lower yielding with lower test weight compared to the conventional management system. Significant cultivar × environment interactions were found for grain yield, grain protein content and grain fill rate. For grain protein content, cross-over interactions of the cultivars between the management systems were observed. Three cultivars (Marquis, Unity and Minnedosa) exhibited minimal comparative loss in grain yield and grain protein content under organic field conditions, and hence could potentially serve as parents for organic wheat breeding programs.  相似文献   
673.
674.
Abstract: This study summarized recent results on POR and plastid development in order to find an explanation for the existence of Pchlide spectral forms. This review has summarized many researches about the Pchlide spectral forms and their phototransformability in different higher plants which have been published. Chlorophyll (Chl) is the most important pigment on the Earth. Each spring millions of tons Chl are formed during bud break and leaf development. The sun light needed for photosynthesis is captured by Chl and transformed to chemical energy. In the Biosynthesis of chlorophyll (Chl) begins with the synthesis of delta-aminolevulinic acid (ALA) from glutamic acid. Chl biosynthetic pathway, a light dependent enzyme protochlorophyllide oxidoreductase (POR) catalyses a key light-driven reaction, trans addition of hydrogen across the C-17-C-18 double bond of the Chl precursor, protochlorophyllide (Pchlide), that triggers a profound transformation in plant development. Pchlide is spectrally heterogeneous and exist in different spectral forms having slightly different absorption and fluorescence peaks. The identified Pchlide spectral forms can be sorted into three groups. The first group is designated as short-wavelength forms. This group with fluorescence in the 625-646 nm spectral region has a heterogeneous nature and is made by four components. The second group includes the long-wavelength Pchlide forms with emission maxima between 652 and 657 nm. The third group is found in the extreme red region (670-730 nm) of the fluorescence emission spectra and includes a number of pigment forms with spectral bands of low intensity. This region is also influenced by vibrational bands of the short-and long-wavelength Pchlide forms.  相似文献   
675.
Thyrotoxicosis exhibit collective clinical manifestation, caused by excessive serum thyroid hormones particularity thyroxin. The clinical signs and symptoms included general alteration of metabolic process leading to weight loss fatigue and weakness and some specific disorders such as cardiovascular, neuromuscular reproductive gastrointestinal dermatological and bone disorders. The diagnosis of thyrotoxicosis relay on the thyroid function test carried out by the laboratory serum measurement of thyroxin, triiodothyronine and thyroid stimulating hormones accompanied by other para-medical examinations suggested by clinicians and endociologicst. In thyrotoxicosis serum level of thyroid hormones and thyroxin in particular elevated accompanied by pituitary thyroid stimulating hormone suppression reaching to undetectable level in sever thyrotoxicosis. Among the most common cause of thyrotoxicosis are, thyroid autoimmunity diseases thyroid toxic, adenoma toxic nodular and multinodular hyperthyroidism. The main aim behind this review is to explore the clinical manifestation, the causative factors, diagnosis, metabolic disorder occur due to thyrotoxicosis.  相似文献   
676.
Assessment of the effect of combination of intrathecal midazolam and lidocaine on postoperative pain was the aim of this study. This randomized controlled trial was performed during 2007 in a teaching hospital of Arak University of Medical Sciences. Forty five male patients who were candidates for elective inguinal herniorrhaphy entered the study and randomly divided into three groups of control (lidocaine 5% plus normal saline), M 0.5 (lidocaine 5% and midazolam 0.5 mg) and M 1.0 (lidocaine 5% and midazolam 1 mg) according intrathecal solution injected for spinal anesthesia. Mean arterial blood pressure, heart rate, post-operative pain, narcotic requirements and complications (nausea, vomiting, pruritic, headache, hypotension and bradycardia) were recorded. The severity of post-operative pain was lowest in M 1.0 group in all postoperative measurements except at 2 h after operation. With regard of complications, only there was significant difference in vomiting between three groups which had the highest frequency in M 0.5 group. No severe hypotension was seen; though, bradycardia occurred in one patient in M 0.5 group which needed treatment. Present findings suggest that administration of intrathecal midazolam (especially 1 mg) together with lidocaine is effective in reducing post-operative pain in patients undergoing open inguinal herniorrhaphy and is not associated with adverse effect.  相似文献   
677.
Flumazenil is one of imidazo-benzodiazepine (Anexate) which has been generally used as benzodiazepine competitive antagonist for the treatment of benzodiazepine intoxication during recent decades. Some has recommended diagnostic usage in ICU as well, for suspected benzodiazepine intoxicated cases. In this study we present a patient intoxicated with lorazepam who developed a ventricular tachycardia after receiving flumazenil as therapeutic mean, though the attack was appropriately terminated by administration of a bolus dose of Amiodarone. We believe that the ventricular tachycardia onset in above mentioned case is secondary to Flumazenil administration in susceptible patient with previous history of ischemic heart disease. Ventricular tachycardia has rarely reported as flumazenil side effects.  相似文献   
678.
Basement membrane of glomerular mesangium (BMG) is one of important components which play a key role to support of the capillary loops in a renal glomerulus and completeness of BMG due to interaction of ureteric bud and metanephric mesenchyme during glomerulogenesis. As laminin contribute in extra cellular matrix and especially in basement membrane, the aim of the present study was to demonstrate the distribution of this molecule so, in this investigation specific antibody against laminin have been used in light microscopy to study development of BMG of fetal and postnatal mouse glomerular mesangium. Female inbred Balb/c mice were selected and were kept under normal condition and finding vaginal plug was assumed as day zero of pregnancy. Two pregnant mice were sacrificed by cervical dislocation in one of gestational days 13-18, respectively and their fetuses were fixed, serially sectioned and by using antibody against laminin in BMG were carried out. The same process was used for kidneys preparation at 15 postnatal days. Present data revealed that laminin showed weak reaction on day 14 of gestation. The amount of laminin increased continuously until next days of fetal life and primary of 10 days postnatal in BMG. After this period, laminin reaction did not show significant change in newborns. These data indicate that laminin appears just during the glomerulogenesis and because of continuity with vasculature which is required for Extra Cellular Matrix (ECM) and glomerular endothelial cell differentiation, laminin, is the one of major structural proteins in BMG.  相似文献   
679.
Cell cycle stage and synchronization of donor cells are important factors influencing the success of somatic cell nuclear transfer. This study examined whether serum starvation has any effect on specific cell death. We also studied the effects of serum starvation, culture to confluence, and full confluency (confluent + 72 h) on cell cycle characteristics and apoptosis of goat dermal fibroblast cells. The cells were obtained from the ear of a 1.5‐year‐old female goat. The following experimental groups were analysed for fibroblast cells: (i) normally growing, (ii) confluent, (iii) full confluency, (iv) cells starved for 48 h and (v) cells starved for 72 h. Analysis of cell cycle distribution by flow cytometry showed that 4.56 and 51.88% of normal cycling cells were at the G0 and G1 phases respectively. In the confluent group, 80% of the cells were arrested in the G0/G1 phase. Serum starvation for 48 and 72 h arrested 84.78% and 90.1% cells at the G0/G1 phase respectively which showed a significant difference when compared with the control group (p < 0.05). Double staining by PI and FITC distinguishes G0 phase from G1 phase. In the full confluency group, 91.53% of cells were at G0/G1 stage, but in contrast to the serum starved group, this high percentage of G0/G1 cells was mainly associated with G1 cells. Under normal culture conditions, 6.39% of cells underwent early apoptosis. In the confluent group 8.93% of cells showed early apoptosis. Serum starvation for 48 and 72 h caused early apoptosis in 8.91 and 39.83% of the cells respectively. Full confluency treatment did not increase the number of apoptotic cells significantly (8.67%). After 72 h, serum starvation significantly increased early apoptosis (p < 0.05). In conclusion, the use of full confluency is suitable for cell cycle synchronization because it arrests cells at the G0/G1 phase and also induces less apoptosis in comparison with the serum starvation group.  相似文献   
680.
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