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排序方式: 共有191条查询结果,搜索用时 203 毫秒
21.
BACKGROUND: Breast cysts are mainly benign and are reported in association with fibrocystic disease and phyllodes tumor. Rarely have cystic changes been reported to occur in malignant tumors. They are usually small but large in rare cases. Giant breast cysts are very rare, and only a few cases have been reported. CASE: A 37-year-old woman presented with a rapidly growing breast mass. Mammography showed a huge, well-circumscribed cystic mass (17 x 16 x 16 cm) suggestive of a benign lesion. Cytologic examination revealed a highly cellular tumor composed of malignant cells of various sizes and shapes in a necrotic background. The smears were diagnosed as positive for malignancy and suggested metaplastic carcinoma. Mastectomy was performed, and histologic study confirmed the cytologic diagnosis. CONCLUSION: This is the first reported case of a breast cyst of this size. Clinically the cyst was confused with a benign lesion. The fine needle aspiration aided the diagnosis and planning of treatment. 相似文献
22.
Lee EJ Lee HJ Kamli MR Pokharel S Bhat AR Lee YH Choi BH Chun T Kang SW Lee YS Kim JW Schnabel RD Taylor JF Choi I 《Genomics》2012,100(3):195-202
We report a systematic study of gene expression during myogenesis and transdifferentiation in four bovine muscle tissues and of adipogenesis in three bovine fat tissues using DNA microarray analysis. One hundred hybridizations were performed and 7245 genes of known and unknown function were identified as being differentially expressed. Supervised hierarchical cluster analysis of gene expression patterns revealed the tissue specificity of genes. A close relationship in global gene expression observed for adipocyte-like cells derived from muscle and adipocytes derived from intramuscular fat suggests a common origin for these cells. The role of transthyretin in myogenesis is a novel finding. Different genes were highly induced during the transdifferentiation of myogenic satellite cells and in the adipogenesis of preadipocytes, indicating the involvement of different molecular mechanisms in these processes. Induction of CD36 and FABP4 expression in adipocyte-like cells and adipocytes may share a common pathway. 相似文献
23.
Zohreh Habibi Rasool Kheyrabadi Sabrieh Ghasemi Maryam Yousefi Seik Weng Ng 《Phytochemistry letters》2012,5(4):705-707
A new eudesmane-type sesquiterpenoid together with two known flavonoids were isolated from the chloroform extract of the aerial part of Sclerorhachis platyrachis. The structure of the new compound was deduced from its comprehensive spectroscopic analysis including IR, EI-MS, 1H NMR, 13C NMR, DEPT, COSY, HMBC and HMQC and was shown to be 4R*-hydroxy-6S*-tigloyloxyeudesma-7S*-11 (13)-en-12-oic acid (1). Finally, the structure of the new compound was unambiguously confirmed by single-crystal X-ray analysis. The structure of known compounds 2 and 3 were identified by comparison of their spectral data with those reported in the literature. 相似文献
24.
Abolfathi M Hajimoradloo A Ghorbani R Zamani A 《Comparative biochemistry and physiology. Part A, Molecular & integrative physiology》2012,161(2):166-173
We evaluated the effects of starvation and refeeding on digestive enzyme activities in juvenile roach, Rutilus rutilus caspicus. Fish were divided into four feeding groups (mean mass 1.68 ± 0.12 g). The control group was fed to satiation twice a day throughout the experiment with formulated diet (SFK). The other three groups were deprived of feed for 1(S1), 2(S2), and 3(S3) weeks, respectively, and then fed to satiation during the refeeding period. The results showed that trypsin specific activity was not affected significantly either by starvation or refeeding, in all experimental groups. Chymotrypsin specific activity did not change significantly in S1 fish during the experimental period. In S2 and S3 fish no significant changes were observed during the starvation period. Upon refeeding, the activity increased in S2 fish, while it decreased in S3 fish. Amylase specific activity decreased significantly during the starvation period in all experimental groups. Upon refeeding, the activity increased. Alkaline phosphatase specific activity did not change significantly during the experiment period in S3 fish, while it showed significant changes during the starvation and refeeding period in the S1 and S2 fish. Starvation also had a significant effect on the structure of the intestine. 相似文献
25.
Lioudyno MI Broccio M Sokolov Y Rasool S Wu J Alkire MT Liu V Kozak JA Dennison PR Glabe CG Lösche M Hall JE 《PloS one》2012,7(4):e35090
The impact of synthetic amyloid β (1-42) (Aβ(1-42)) oligomers on biophysical properties of voltage-gated potassium channels Kv 1.3 and lipid bilayer membranes (BLMs) was quantified for protocols using hexafluoroisopropanol (HFIP) or sodium hydroxide (NaOH) as solvents prior to initiating the oligomer formation. Regardless of the solvent used Aβ(1-42) samples contained oligomers that reacted with the conformation-specific antibodies A11 and OC and had similar size distributions as determined by dynamic light scattering. Patch-clamp recordings of the potassium currents showed that synthetic Aβ(1-42) oligomers accelerate the activation and inactivation kinetics of Kv 1.3 current with no significant effect on current amplitude. In contrast to oligomeric samples, freshly prepared, presumably monomeric, Aβ(1-42) solutions had no effect on Kv 1.3 channel properties. Aβ(1-42) oligomers had no effect on the steady-state current (at -80 mV) recorded from Kv 1.3-expressing cells but increased the conductance of artificial BLMs in a dose-dependent fashion. Formation of amyloid channels, however, was not observed due to conditions of the experiments. To exclude the effects of HFIP (used to dissolve lyophilized Aβ(1-42) peptide), and trifluoroacetic acid (TFA) (used during Aβ(1-42) synthesis), we determined concentrations of these fluorinated compounds in the stock Aβ(1-42) solutions by (19)F NMR. After extensive evaporation, the concentration of HFIP in the 100× stock Aβ(1-42) solutions was ~1.7 μM. The concentration of residual TFA in the 70× stock Aβ(1-42) solutions was ~20 μM. Even at the stock concentrations neither HFIP nor TFA alone had any effect on potassium currents or BLMs. The Aβ(1-42) oligomers prepared with HFIP as solvent, however, were more potent in the electrophysiological tests, suggesting that fluorinated compounds, such as HFIP or structurally-related inhalational anesthetics, may affect Aβ(1-42) aggregation and potentially enhance ability of oligomers to modulate voltage-gated ion channels and biological membrane properties. 相似文献
26.
27.
Mushtaq Hussain Syeda Qamarunnissa Saboohi Raza Javed Qureshi Abdul Wajid Sheikh A. Rasool 《Biologia》2009,64(5):852-858
DNA photolyase is perhaps the most ancient and direct arsenal in curing the UV-induced dimers formed in the microbial genome.
Out of two cofactors of the enzyme, catalytic and light harvesting, differences in the latter have provided basis for categorizing
photolyases of prokaryotes as folate and deazaflavin types. In the present study, the homology modeling of DNA photolyase
of Enterococcus faecalis was undertaken. The predicted models were structurally compared with the crystal structure coordinates of photolyases from
Escherichia coli (folate type) and Anacystis nidulans (deazaflavin type). Discrepancies present in the multiple sequence alignment and tertiary structures, particularly at the
light harvesting cofactor (methenyltetrahydrofolic acid, MTHF; 8-hydroxy-5-deazaflavin, 8-HDF) binding sites indicated the
mechanistic nature of enterococcal photolyase. Concisely, despite the greater holistic homology with folate-type photolyase,
enterococcal photolyase was characterized as deazaflavin-type. The presence of 8-HDF binding sites and groove architecture
of substrate binding sites were also found supportive in this regard. The inter cofactor distance and/or orientation also
implied to the efficient energy transfer in photolyase of Enterococcus in comparison with E. coli. In addition, we observed relatively high protein deformability in the enterococcal genome, which may favors the repair action
of photolyase. The findings are expected to provide molecular insights into the difference in sunlight inactivation rate of
two important fecal contamination indicators, namely Enterococcus and E. coli. 相似文献
28.
Muhammad Hidayat Rasool 《Indian journal of microbiology》2008,48(3):401-404
The present study was conducted to develop and evaluate an experimental ISCOM-based infectious bursal disease (IBD) vaccine.
The indigenous very virulent infectious bursal disease virus (vvIBDV) already attenuated and adapted to Vero cell line was
used. After denaturation of viral proteins with sodium dodecyl sulphate (SDS), an IBD-ISCOM was constructed. The non-incorporated
viral components were separated from ISCOM by centrifugation of dialysate. The pathogenicity and immunogenicity trials were
conducted in 3-week-old broiler chicken. A commercial oil-emulsified vaccine (CEVAC IBD K) was used for comparison. There
were no clinical signs of disease, gross or microscopic lesions in bursa of Fabricius in group G1 vaccinated with ISCOM-based
vaccine and bursa to body weight ratio were comparable to un-vaccinated control group (G3). The virus-neutralizing antibody
titers were significantly (P<0.05) higher in group G1 as compared with group G2 which was vaccinated with commercial vaccine.
On challenge with vvIBDV, 100%, 75% and 0.00% protection was achieved in G1, G2 and G3, respectively. The results indicated
that ISCOM-based IBD vaccine is safe and immunogenic. 相似文献
29.
30.
Atahar Husein Azfar Jamal Mohammad Zulfazal Ahmed Mohammad Arish Rahat Ali Shams Tabrez Fayyaz Rasool Abdur Rub 《Journal of cellular biochemistry》2018,119(9):7844-7854
Leishmania is a protozoan parasite that resides and replicates in macrophages and causes leishmaniasis. The parasite alters the signaling cascade in host macrophages and evades the host machinery. Small G‐proteins are GTPases, grouped in 5 different families that play a crucial role in the regulation of cell proliferation, cell survival, apoptosis, intracellular trafficking, and transport. In particular, the Ras family of small G‐proteins has been identified to play a significant role in the cellular functions mentioned before. Here, we studied the differential expression of the most important small G‐proteins during Leishmania infection. We found major changes in the expression of different isoforms of Ras, mainly in N‐Ras. We observed that Leishmania donovani infection led to enhanced N‐Ras expression, whereas it inhibited K‐Ras and H‐Ras expression. Furthermore, an active N‐Ras pull‐down assay showed enhanced N‐Ras activity. L donovani infection also increased extracellular signal–regulated kinase 1/2 phosphorylation and simultaneously decreased p38 phosphorylation. In contrast, pharmacological inhibition of Ras led to reduction in the phosphorylation of extracellular signal–regulated kinase 1/2 and enhanced the phosphorylation of p38 in Leishmania‐infected cells, which could lead to increased interleukin‐12 expression and decreased interleukin‐10 expression. Indeed, farnesylthiosalicyclic acid (a Ras inhibitor), when used at the effective level in L donovani–infected macrophages, reduced amastigotes in the host macrophages. Thus, upregulated N‐Ras expression during L donovani infection could be a novel immune evasion strategy of Leishmania and would be a potential target for antileishmanial immunotherapy. 相似文献