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61.
Lower Permian Bryozoan fauna of Jamal Formation, exposed in Bagh-e Vang (Shotori Mountains, northeast Iran) includes six species. Three species – Streblotrypa (Streblascopora) marmionensis (Etheridge 1926), Rhabdomeson bispinosum (Crockford 1944) and Alternifenestella kungurensis (Stuckenberg 1898) – indicate the Lower Permian (Artinskian to Kungurian) age of the formation. Three additional taxa – Fistulipora sp. 1, Fistulipora sp. 2 and undetermined timanodictyid bryozoan ?Timanodictya sp. could not be identified at the species level. The investigated fauna refers to Uralian and Australian palaeobiogeographic provinces.  相似文献   
62.
'Rhupus' is a rare condition sharing features of rheumatoid arthritis (RA) and systemic lupus erythematosus (SLE). If rhupus is a distinctive entity, an overlap between RA and SLE or a subset of SLE is currently debated. This study was performed to explore the prevalence of antibodies against cyclic citrullinated peptides (anti-CCP antibodies) in rhupus. Patients meeting American College of Rheumatology criteria for RA, SLE, or both were included. Clinical and radiographic features were recorded and sera were searched for anti-CCP antibodies, rheumatoid factor, antinuclear antibodies, anti-extractable nuclear antigens, and antibodies against double-stranded DNA (anti-dsDNA antibodies). Seven patients for each group were included. Clinical and serological features for RA or SLE were similar between rhupus and RA patients, and between rhupus and SLE patients, respectively. Values for anti-CCP antibodies obtained were significantly (p < 0.05) higher in RA (6/7) and rhupus (4/7) than in SLE patients (0/7) and healthy subjects (0/7). Our data support the possibility that rhupus is an overlap between RA and SLE, because highly specific autoantibodies for RA (anti-CCP) and for SLE (anti-dsDNA and anti-Sm) are detected in coexistence.  相似文献   
63.
Considering the unfavourable response of breast cancer (BC) to treatment, we assessed the therapeutic potential hesperidin in mice bearing 4T1 BC tumours. Anti-tumour effects were assessed by measuring pathologic complete response (pCR), survival analysis, immunohistochemistry for E-cadherin, VEGF, MMP9, MMP2 and Ki-67, serum measurement of IFNγ and IL-4, and gene expression analysis of CD105, VEGFa, VEGFR2 and COX2. Survival of tumour-bearing mice was the highest in mice receiving a combination of hesperidin and doxorubicin (Dox) (80%) compared to the normal saline (43%), hesperidin 5 (54%), 10 (55.5%), 10 (60.5%) and 40 (66%) mg/kg, and 10 mg/kg Dox-treated (73%) groups (p < 0.0001 for all). Compared to the normal saline group, there was a significant elevation in IFNγ level in the animals receiving 20 (p = 0.0026) and 40 (p < 0.001) mg/kg hesperidin, 10 mg/kg Dox (p < 0.001), and combined hesperidin (20 mg/kg) and Dox (10 mg/kg) (p < 0.001). A significant reduction in the gene expression of CD 105 (p = 0.0106), VEGFa (p < 0.0001), VEGFR2 (p < 0.0001), and Cox2 (p = 0.034) and a significant higher pCR score (p = 0.006) were noticed in mice treated with 10 mg/kg Dox + 20 mg/kg hesperidin compared to those treated with 10 mg/kg Dox alone. Immunohistochemical staining showed significant reductions in Ki-67 (p < 0.001) and VEGF (p < 0.001) and a significant elevation in E-cadherin (p = 0.005) in the 10 mg/kg Dox + 20 mg/kg treatment group than in 10 mg/kg Dox alone group. Hesperidin can be considered as a potentially suitable anti-cancer agent for BC that can synergize with other chemotherapeutics.  相似文献   
64.
Breast cancer (BC) is an important cause of female cancer-related death. It has recently been demonstrated that metabolic disorders including lipid metabolism are a hallmark of cancer cells. Lipin-1 is an enzyme that displays phosphatidate phosphatase activity and regulates the rate-limiting step in the pathway of triglycerides and phospholipids synthesis. The objective of this study was to evaluate lipin-1 expression, its prognostic significance, and its correlation with p53 tumor suppressor in patients with BC. In this study, 55 pairs of fresh samples of BC and adjacent noncancerous tissue were used to analyze lipin-1, using quantitative real-time polymerase chain reaction and immunohistochemistry (IHC) staining. The expression of other clinicopathological variables and p53 was also examined using IHC technique. The cell migration was studied in MCF-7 and MDA-MB231 cells following the inhibition of lipin-1 by propranolol. Our results show that the relative expression of lipin-1 messenger RNA was significantly higher in BC tissues compared with the adjacent normal tissue and its inhibition reduced cell migration in cancer cells. This upregulation was negatively correlated with histological grade of tumor and p53 status (p = .001 and p = .034) respectively and positively correlated with the tumor size (p = .006). Our results also seem to indicate that the high lipin-1 expression is related to a good prognosis in patients with BC. The expression of lipin-1 may be considered as a novel independent prognostic factor. The inhibition of lipin-1 may also have therapeutic significance for patients with BC. The correlation between lipin-1 and p53 confirms the role of p53 in the regulation of lipid metabolism in cancer cells.  相似文献   
65.
Though the HIV/AIDS epidemic in Southeastern Europe is one of low reported prevalence, numerous studies have described the pervasiveness of medical providers’ lack of knowledge of HIV/AIDS in the Balkans. This study sought to culturally adapt an instrument to assess medical providers’ knowledge of and attitudes towards HIV/AIDS in Albania. Cultural adaptation was completed through development of a survey from previously validated instruments, translation of the survey into Albanian, blinded back translation, expert committee review of the draft instrument, focus group pre-testing with community- and University Hospital Center of Tirana-based physicians and nurses, and test-retest reliability testing. Blinded back translation of the instrument supported the initial translation with slight changes to the idiomatic and conceptual equivalences. Focus group pre-testing generally supported the instrument, yet some experiential and idiomatic changes were implemented. Based on unweighted kappa and/or prevalence adjusted bias adjusted kappa (PABAK), 20 of the 43 questions were deemed statistically significant at kappa and/or PABAK ≥0.5, while 12 others did not cross zero on the 95% confidence interval for kappa, indicating their probable significance. Subsequently, an instrument to assess medical providers’ knowledge of and attitudes toward HIV/AIDS for an Albanian population was developed which can be expanded within Albania and potentially to other countries within the Balkans, which have an Albanian-speaking population.  相似文献   
66.
67.
The differential transform method (DTM) is semi-numerical method which is used to study the steady, laminar buoyancy-driven convection heat transfer of a particulate biofluid suspension in a channel containing a porous material. A two-phase continuum model is used. A set of variables is implemented to reduce the ordinary differential equations for momentum and energy conservation (for both phases) to a dimensionless system. DTM solutions are obtained for the dimensionless system under appropriate boundary conditions. We examine the influence of momentum inverse Stokes number (Skm), Darcy number (Da), Forchheimer number (Fs), particle loading parameter (pL), particle-phase wall slip parameter (Ω) and buoyancy parameter (B) on the fluid-phase velocity (U) and particle-phase velocity (Up). Padé approximants are also employed to achieve satisfaction of boundary conditions. Excellent correlation is obtained between the DTM and numerical quadrature solutions. The results indicate that there is a strong decrease in fluid-phase velocities with increasing Darcian (first-order) drag and the second-order Forchheimer drag, and a weaker reduction in particle-phase velocity field. Fluid and particle-phase velocities are also strongly affected with inverse momentum Stokes number. DTM is shown to be a powerful tool providing engineers with an alternative simulation approach to other traditional methods for multi-phase computational biofluid mechanics. The model finds applications in haemotological separation and biotechnological processing.  相似文献   
68.
We compared histochemical and immunohistochemical staining as well as fluorochrome labeling in murine bone specimens that were fixed with 10% neutral buffered formalin to those fixed with HistoChoice®. We showed that sections from undecalcified tibiae fixed for 4 h in HistoChoice® resulted in enhanced toluidine blue and Von Kossa histochemical staining compared to formalin fixation. HistoChoice® produced comparable or improved staining for alkaline phosphatase. Acid phosphatase localization was better in formalin fixed specimens, but osteoclasts were visuralized more easily in HistoChoice® fixed specimens. As expected, immunohistochemical labeling was antibody dependent; some antibodies labeled better in HistoChoice® fixed specimens while others were better in formalin fixed specimens. Toluidine blue, Von Kossa, and alkaline phosphatase staining of sections fixed for 12 h produced sections that were similar to 4 h fixed sections. Fixation for 12 h preserved acid phosphatase activity better. Increasing fixation to 12 h affected immunolocalization differentially. Bone sialoprotein labeling in HistoChoice® fixed specimens was comparable to formalin fixed samples. On the other hand, after 12 h formalin fixation, osteocalcin labeling was comparable to HistoChoice®. For most histochemical applications, fixing murine bone specimens for 4 h with HistoChoice® yielded superior staining compared to formalin fixation. If immunohistochemical localization is desired, however, individual antibodies must be tested to determine which fixation process retains antigenicity better. In addition, there was no detectable difference in the intensity of fluorochrome labeling using either fixative. Finally, fixation duration did not alter the intensity of labeling.  相似文献   
69.
Altruistic suicide is best known in the context of programmed cell death (PCD) in multicellular individuals, which is understood as an adaptive process that contributes to the development and functionality of the organism. After the realization that PCD‐like processes can also be induced in single‐celled lineages, the paradigm of altruistic cell death has been extended to include these active cell death processes in unicellular organisms. Here, we critically evaluate the current conceptual framework and the experimental data used to support the notion of altruistic suicide in unicellular lineages, and propose new perspectives. We argue that importing the paradigm of altruistic cell death from multicellular organisms to explain active death in unicellular lineages has the potential to limit the types of questions we ask, thus biasing our understanding of the nature, origin, and maintenance of this trait. We also emphasize the need to distinguish between the benefits and the adaptive role of a trait. Lastly, we provide an alternative framework that allows for the possibility that active death in single‐celled organisms is a maladaptive trait maintained as a byproduct of selection on pro‐survival functions, but that could—under conditions in which kin/group selection can act—be co‐opted into an altruistic trait.  相似文献   
70.
The reaction of the zinc(II) acetate and 1,4-bis(3-pyridyl)-2,3-diaza-1,3-butadiene (3-bpdb) in presence of perchlorate anions produces a new one-dimensional coordination polymer, {[Zn(μ-3-bpdb)(3-bpdb)2(H2O)2](ClO4)2·3-bpdb}n (1). The compound 1 has been characterized by IR, 1HNMR and 13CNMR spectroscopies. The single crystal X-ray data shows an infinite one-dimensional structure that grows in two- and three-dimensions by hydrogen bonding and π-π stacking. The compound 1 also has been synthesized at micro-size by sonochemical processes and characterized by IR and X-ray powder diffraction (XRD). The scanning electron microscopy (SEM) shows compound 1 has been grown as micro-rod morphology. The thermal stabilities at bulk and micro-size scale were studied by thermal gravimetric (TG) and differential thermal analysis (DTA). The ZnO nanoparticles were obtained by direct calcination at 400 °C under air atmosphere and by thermolysis in oleic acid at 200 °C. The obtained zinc(II) oxide nanoparticles were characterized by X-ray diffraction (XRD) and scanning electron microscopy (SEM).  相似文献   
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