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71.
Upper Permian (Murghabian) sponges from the Surmaq Formation exposed in the Hambast Mountains, south of Abadeh, central Iran are described. The sponge fauna of the Surmaq Formation is composed of at least 26 taxa, including 12 species of sphinctozoans, 12 species of inozoans, one operculospongid, and one lithistid species. The following taxa were determined to genus or species level: Sphinctozoa: Family Sebargasiidae: Amblysiphonella hambastensis n. sp., Discosiphonella iranica n. sp., Family Colospongiidae: Colospongia cortexifera Senowbari-Daryan and Rigby, Exaulipora permica (Senowbari-Daryan), Platythalamiella sp. 1, Platythalamiella? sp. 2, Parauvanella minima Senowbari-Daryan, Colospongia? or Neoguadalupia? sp., Family Guadalupiidae: Cystothalamia surmaqensis n. sp., Imbricatocoelia cf. paucipora Rigby, Fan and Zhang, Family Thaumastocoeliidae: Sollasia ostiolata Steinmann, Family Cryptocoeliidae: Stylocoelia circopora Wu. Inozoa: Family Peronidellidae: Preperonidella cf. Preperonidella recta grossa (Wu), Heptatubispongia symmetrica Rigby and Senowbari-Daryan, Hambastella sincassa n. gen., n. sp., Hambastella cumcassa n. sp., Family Maeandrostiidae: Maeandrostia kansasensis Girty, Maeandrostia? dubia n. sp., Surmaqella pustulata n. gen., n. sp., Family Auriculospongiidae: Pseudopalaeoaplysina huayingensis Wang, Qiang and Zhang, Family Disjectoporidae: Disjectopora beipeiensis Fan, Rigby and Zhang, Lichuanopora cf. bancaoensis Fan, Rigby and Zhang, Family Khmeriidae: Imilce newelli Flügel. Lithistida: Family Astylospongiidae: Raanespongia iranica n. sp. Among the sphinctozoans A. hambastensis n. sp. is an extremely abundant species. Among the inozoans the genus Hambastella n. gen., with both species, is the most abundant genus. The genera Disjectopora, Lichuanopora, and Pseudopaleoaplysina, were described as hydrozoans by early workers, but are assigned to the inozoans in this paper. The Upper Permian sponge fauna, as well as the composition of other reef organisms, from the Hambast Mountains in central Iran is different from that of the assemblage in the Lower Permian reefal limestones of Bagh-e Vang from the Shotori Mountians (northeast Iran).  相似文献   
72.
73.
Non–small-lung cancer (NSCLC) is the leading cause of cancer death. Early detection of NSCLC could pave the way for effective therapies. Analysis of molecular genetic biomarkers in biological fluids has been proposed as a useful tool for cancer diagnosis. Here, we aimed to develop a panel of noncoding RNAs (ncRNAs) in sputum for NSCLC early detection. Expression of 11 ncRNAs were analyzed by real–time polymerase chain reaction in sputum samples of 30 NSCLC patients and 30 sex- and age-matched cancer-free controls. Stability of endogenous microRNAs (miRNAs) in sputum was evaluated after 3 and 6 days at 4°C, 6 months, and 1 year at −80°C. Nine ncRNAs showed significant differences of their expression in sputum between NSCLC patients and controls. A logistic regression model with the best prediction was built based on miR-145, miR-126, and miR-7. The composite of the three miRNAs produced 90% sensitivity and specificity in distinguishing NSCLC patients from the controls. Results indicate that miRNAs could be useful biomarkers based on their stability under various storage conditions and maintain differential changes between cancer and control groups. Moreover, measurement of miRNAs in sputum could be a noninvasive approach for detection of lung cancer.  相似文献   
74.
Lineweaver-Burk plot analysis is the most widely used method to determine enzyme kinetic parameters. In the spectrophotometric determination of enzyme activity using the Lineweaver-Burk plot, it is necessary to find a wavelength at which only the substrate or the product has absorbance without any spectroscopic interference of the other reaction components. Moreover, in this method, different initial concentrations of the substrate should be used to obtain the initial velocities required for Lineweaver-Burk plot analysis. In the present work, a multi-wavelength model-based method has been developed and validated to determine Michaelis-Menten constants for some enzyme reactions. In this method, a selective wavelength region and several experiments with different initial concentrations of the substrate are not required. The absorbance data of the kinetic assays are fitted by non-linear regression coupled to the numeric integration of the related differential equation. To indicate the applicability of the proposed method, the Michaelis-Menten constants for the oxidation of phenanthridine, 6-deoxypenciclovir and xanthine by molybdenum hydroxylases were determined using only a single initial concentration of the substrate, regardless of any spectral overlap.  相似文献   
75.
A mathematical model using simple concepts of repeated games is proposed to model the course and prognosis of factitious disorders. Although simple, the model seems capable of explaining the yet unknown mechanisms underlying the variable course of factitious disorders. One of the notable results of this study is the significant effect of involved physicians in the treatment process on the course of the disease. Particularly, the doctor's error rate in realizing whether the symptoms are real or factitious can considerably affect the course of the disease. This is the first paper to apply a mathematical model to factitious disorders.  相似文献   
76.
Calcareous algae and microproblematica have been studied in the Middle Permian part of the Dalan Formation in Dena Mountain, Zagros, southwest Iran. Murgabian (=Wordian) microfossils are the most diversified. The assemblages encompass, among the dasycladales, Anthracoporella spectabilis, Epimastopora piae, Epimastoporella japonica, E. likana, Paraepimastopora? cf. densipora n. comb., Gyroporella cf. nipponica, G.? aff. fluegeli n. comb., G.? aff. symmetrica, G.? aff. digitula n. comb., Mizzia yabei; among the gymnocodiaceans, Gymnocodium bellerophontis, G. nodosum, Permocalculus cf. digitatus, P. forcepinus, P. cf. fragilis, P. plumosus, P. cf. solidus, Tauridium? sp.; among the “phylloid algae” Eugonophyllum? sp.; among the other incertae sedis algae Stacheoides sp., Ungdarella uralica, Fourstonella (Efluegelia) johnsoni, and among some microproblematica alternatively assigned to foraminifers or algae Aeolisaccus dunningtoni, Tubiphytes obscurus, Pseudovermiporella nipponica, P. sodalica, and P. longipora. Each taxon is briefly characterized, whereas a more detailed analysis of the epimastoporacean algae is given. Among them, the genera Epimastopora and Epimastoporella are emended. All the described microfossils have a relatively broad stratigraphic distribution in the Permian period but they are paleoecologically important. They are indeed confident micropaleontological Middle Permian proxies, particularly for shallow-marine, warm, well-oxygenated and relatively high-energy environments. They were affected by the end-Guadalupian crisis because they strongly decrease in the upper carbonate unit of the Dalan Formation and are not found in the Triassic sediments of the area.  相似文献   
77.
Acute coronary syndromes (ACS) may be triggered by acute infections. Systemic production of interferon gamma (IFN-γ) is induced during infection and regulates the production of matrix metalloproteinases (MMPs) and their inhibitors (TIMPs), both important in plaque stability. This study evaluates the effect of IFN-γ on the MMPs/TIMP-1 ratio in cultured monocytes from 30 patients with stable coronary artery disease (CAD), 30 with unstable angina (UA) or non-ST-segment elevation myocardial infarction (NSTEMI), and 30 healthy blood donors. Supernatant concentrations of MMP-1, -2, -9, and TIMP-1 were measured by enzyme-linked immunoassays. Basal concentration of MMP-1 and TIMP-1 was similar between groups, while MMP-2 was higher in healthy individuals and MMP-9 in patients with UA/NSTEMI. Upon IFN-γ stimulation, MMP-9 secretion increased in all groups, while TIMP-1 decreased only in patients with CAD, which in turn result in a strikingly elevation in their mean MMP-9/TIMP-1 ratio. MMP-1/TIMP-1 and MMP-2/TIMP-1 ratios were <1.0 in basal conditions and after stimulation in all groups. Our results suggest that nonstimulated monocytes from patients with stable CAD show a similar behavior than those from healthy individuals. However, stimulation with IFN-γ induces an increase on the MMP-9/TIMP-1 ratio as high as that found in patients with ACS. Thus, it may bring biological plausibility to the association between acute infections and the development of ACS.  相似文献   
78.
In this study combined heat and mass transfer by mixed convective flow along a moving vertical flat plate with hydrodynamic slip and thermal convective boundary condition is investigated. Using similarity variables, the governing nonlinear partial differential equations are converted into a system of coupled nonlinear ordinary differential equations. The transformed equations are then solved using a semi-numerical/analytical method called the differential transform method and results are compared with numerical results. Close agreement is found between the present method and the numerical method. Effects of the controlling parameters, including convective heat transfer, magnetic field, buoyancy ratio, hydrodynamic slip, mixed convective, Prandtl number and Schmidt number are investigated on the dimensionless velocity, temperature and concentration profiles. In addition effects of different parameters on the skin friction factor, , local Nusselt number, , and local Sherwood number are shown and explained through tables.  相似文献   
79.
Th1 cells play a central role in immunity to brucellosis, while the exact role of Th17 cells has remained unknown. This study aimed to evaluate the peripheral distributions of Th1 and Th17 cells and serum levels of IFN-γ, IL-17A and IL-22 cytokines in brucellosis patients. One hundred patients (36 acute, 41 under-treatment and 23 relapsed) and 30 age- and sex-matched healthy controls were included. The frequencies of Th1 and Th17 cells were determined by flow cytometric analysis. Serum levels of IFN-γ, IL-17A and IL-22 were measured by multi-analyte flow assay. Increased frequencies of Th1 and Th17 cells were observed in acute and relapsed brucellosis versus under-treatment patients and healthy controls (P < 0.05). The mean serum levels of IFN-γ were significantly elevated in acute and relapsed groups compared to under-treatment patients (P = 0.002 and P = 0.01 respectively). Acute patients showed higher levels of IL-22 than under-treatment (P = 0.008). Direct correlations were found between increased frequencies of Th1 and Th17 cells in acute and relapsed patients (P = 0.007 and P = 0.001 respectively) and between IL-17A and IL-22 in both groups of patients. Our findings indicate a cooperative role for Th1 and Th17 cells in immunity to brucellosis which is more evident during acute and relapse phases of brucellosis.  相似文献   
80.
Plasmonics - In this paper, we report fabrication of a simple, stable, low-cost, and easy-to-fabricate substrate for&nbsp;surface enhanced Raman spectroscopy (SERS) applications. Silicon...  相似文献   
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