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1.
An experiment was designed to answer two questions as they apply to random skin-flap survival: Is there a therapy that can improve random skin-flap survival when given postoperatively? And if so, when does one start such a therapy? Fluosol-DA 20% (Fluosol) has increased random skin-flap survival when given preoperatively in our laboratory. An experiment was devised to see if it could rescue failing flaps. One-hundred Sprague-Dawley rats were divided into a control (N = 25) and five experimental groups (N = 15). All had 10 X 13 cm reverse McFarlane random flaps raised and reinset. The experimental groups underwent hemodilution with either Ringer's lactate or Fluosol at 4, 8, and 12 hours after flap elevation. All were kept in 50% oxygen for 72 hours postoperatively. The flaps and their corresponding necrotic areas were measured on day 7. As to when to institute a therapy, we simultaneously evaluated the use of a microfluorometer as a monitor of flap survival. Analysis of flap survival showed little difference between control and experimental Ringer's lactate or Fluosol groups. Analysis of the microfluorometric data led to the following points. First, as a monitor of flap viability, it is limited by a lack of specificity and sensitivity. Second, comparison of the data from portions of the flap destined to live with those destined to die suggests that it may not be failure of circulatory inflow that leads to flap death.  相似文献   
2.
The effect of composition of the medium and pH on the growth of Pediastrum duplex Meyen and Dictyosphaerium pulchellum Wood was studied. Both species showed preference to alkaline conditions. The ammonium nitrate grown colonies of D. pulchellum lacked mucilage and showed a more compact form, resembling D. pulchellum var. minitum Deflandre. From this it appears that D. pulchellum var. minitum is a nutritional variant of the species and not a stable variety.  相似文献   
3.
Abstract

The pre-penetration and infection process of Colletotrichum dematium on mulberry leaf was investigated by scanning electron microscope. Conidia produced on germination appressoria directly or at the end of short germ tubes. Appressoria were formed mostly over cuticle, but sometimes over stomata also. At 72 h post-inoculation, an extensive network of sub-cuticular runner hyphae (RH) was produced. The RH were traceable by the cuticular bulgings on leaf surface. The RH emerged to leaf surface through ruptured cuticle to form secondary infection hyphae (SIH). The SIH re-entered the leaf tissue by sending penetration branches through stomata. Conidia were formed singly on short conidiophores from the RH and SIH, at short intervals. The conidia developed on RH were exposed to leaf surface through ruptured cuticle. Some times conidia were released through stomata also. The RH and SIH had thick knots from which hyphal branches and conidia were developed. Definite acervuli were not developed.  相似文献   
4.
Abstract

Leaf yield loss in mulberry due to Macrophomina root rot disease was assessed in three different states of south India at field level. The highest leaf yield loss recorded was in V-1 variety (34.74%), whereas the lowest leaf yield loss was in K-2 variety (28.54%). However, the leaf yields losses in other varieties viz., MR-2 (32.90%), S-36 (32.06%), RFS-175 (31.75%) and S-13 (29.0%) recorded were medium. The average leaf yield loss was 31.49% due to root rot disease caused by M. phaseolina in mulberry.  相似文献   
5.
Inhaled nitric oxide (iNO) is used clinically to treat pulmonary hypertension in newborns, often in conjunction with hyperoxia (NO/O2). Prolonged exposure to NO/O2 causes synergistic lung injury and death of lung epithelial cells. To explore the mechanisms involved, oxygen-resistant HeLa-80 cells were exposed to NO +/- O2. Exposure to NO and O2 induced a synergistic cytotoxicity, accompanied with apoptotic characteristics, including elevated caspase-3-like activity, Annexin V incorporation, and nuclear condensation. This apoptosis was associated with a synergistic suppression of NF-kappaB activity. Cells lacking functional NF-kappaB p65 subunit were more sensitive to NO/O2 than their wild type counterparts. This injury was partially rescued by transfection with a p65 expression construct, suggesting an inverse relationship between NF-kappaB and susceptibility to the cytotoxicity of NO/O2. Despite the reduced NF-kappaB activity in cells exposed to NO +/- O2, IkappaBalpha was degraded, suggesting that pathways regulating the steady-state levels of IkappaB were not involved. However, exposure to NO/O2 caused a marked reduction in nuclear localization and an increase in protein carbonyl formation of NF-kappaB p65 subunit. These results suggest that NO/O2-induced apoptosis occurs by suppressing NF-kappaB activity.  相似文献   
6.
Crimean-Congo hemorrhagic fever (CCHF) virus is one among the major zoonosis viral diseases that use the Hyalomma ticks as their transmission vector to cause viral infection to the human and mammalian community. The fatality of infectious is high across the world especially in Africa, Asia, Middle East, and Europe. This study regarding codon usage bias of S, M, and L segments of the CCHF virus pertaining to the host Homo sapiens, reveals in-depth information about the evolutionary characteristics of CCHFV. Relative Synonymous Codon Usage (RSCU), Effective number of codons (ENC) were calculated, to determine the codon usage pattern in each segment. Correlation analysis between Codon adaptation index (CAI), GRAVY (Hydrophobicity), AROMO (Aromaticity), and nucleotide composition revealed bias in the codon usage pattern. There was no strong codon bias found among any segments of the CCHF virus, indicating both the factors i.e., natural selection and mutational pressure shapes the codon usage bias.  相似文献   
7.
Herpes simplex virus (HSV) entry requires the core fusion machinery of gH/gL and gB as well as gD and a gD receptor. When gD binds receptor, it undergoes conformational changes that presumably activate gH/gL, which then activates gB to carry out fusion. gB is a class III viral fusion protein, while gH/gL does not resemble any known viral fusion protein. One hallmark of fusion proteins is their ability to bind lipid membranes. We previously used a liposome coflotation assay to show that truncated soluble gB, but not gH/gL or gD, can associate with liposomes at neutral pH. Here, we show that gH/gL cofloats with liposomes but only when it is incubated with gB at pH 5. When gB mutants with single amino acid changes in the fusion loops (known to inhibit the binding of soluble gB to liposomes) were mixed with gH/gL and liposomes at pH 5, gH/gL failed to cofloat with liposomes. These data suggest that gH/gL does not directly associate with liposomes but instead binds to gB, which then binds to liposomes via its fusion loops. Using monoclonal antibodies, we found that many gH and gL epitopes were altered by low pH, whereas the effect on gB epitopes was more limited. Our liposome data support the concept that low pH triggers conformational changes to both proteins that allow gH/gL to physically interact with gB.  相似文献   
8.
Amyloglucosidase (EC 3.2.1.3) from Aspergillus niger was employed for the saccharification of mango (Mangifera indica Linn) kernel starch. Response surface methodology based on a three-level three-factor Box-Behnken design was employed to optimize the important process variables such as substrate concentration (137.5-412.5 mg), enzyme concentration (4-12 mg) and temperature (35-55 °C). The sugar yield increased with both enzyme concentration and temperature, and decreased with substrate concentration. The response surface model indicated optimum conditions (substrate, 137.5 mg; enzyme, 12 mg; temperature, 55 °C) for obtaining 0.4851 mg sugar/mg substrate, which was also verified experimentally.  相似文献   
9.
Designed and synthesized novel homopiperazine linked imidazo[1,2-a]pyrimidine derivatives (10a–i, 11a–g, 12), and evaluated them for their in vitro cytotoxicity against HeLa cells (cervical cancer), A549 cells (lung cancer) cells, by MTT assay. Compound 12 (IC50 = 4.14 µM) and compound 10c (IC50 = 5.98 µM) were found to be 2.5 fold, and 1.74 fold more potent when compared with standard Etoposide (IC50 = 10.44 µM), against A549 (lung cancer cells). Compound 12 also found to be 1.57 and 1.13 fold potent against DU145 (IC50 = 6.24 µM) and HeLa (IC50 = 6.54 µM), respectively when compared with Etoposide (DU145, IC50 = 9.8 µM; HeLa, IC50 = 7.43 µM). Compound 10f (IC50 = 6.12 µM) was found to be 1.31 fold more potent than Etoposide (IC50 = 7.43 µM) against HeLa cell lines.Moreover compounds 10a and 11a showed cytotoxicity at low micro-molar concentrations against A549 cells. Synthesized compounds were also evaluated for their antimicrobial activity by Cup plate diffusion method. Compounds 10c, 11b, 11d and 11f displayed remarkable antimicrobial activity relating to their standard drugs Gentamycin, Amphotericin B and Ampicillin. Significantly, compound 10c showed broad spectrum activity against tested microbial strains. All the designed compounds were well occupied the binding site of the colchicine and interacted with both α- and β-tubuline interface (PDB ID: 3E22), which demonstrates that synthesized compounds are promising tubulin inhibitors. Also, the synthesized compounds occupied the catalytic triad and adenine-binding site, in the active site of β-ketoacyl-acyl carrier protein synthase III enzyme (PDB ID: 1MZS). The molecular docking results provided the useful information for the future design of more potent inhibitors. These preliminary results convinced further investigation and modifications on synthesized compounds aiming towards the development of potential cytotoxic as well as antimicrobial agents.  相似文献   
10.
Breast cancers are the leading cancers among females. Diagnosis by fine needle aspiration cytology (FNAC) is the gold standard. The widely practiced screening method, mammography, suffers from high false positive results and repeated exposure to harmful ionizing radiation. As with all other cancers survival rates are shown to heavily depend on stage of the cancers (Stage 0, 95%; Stage IV, 75%). Hence development of more reliable screening and diagnosis methodology is of considerable interest in breast cancer management. Raman spectra of normal, benign, and malignant breast tissue show significant differences. Spectral differences between normal and diseased breast tissues are more pronounced than between the two pathological conditions, malignant and benign tissues. Based on spectral profiles, the presence of lipids (1078, 1267, 1301, 1440, 1654, 1746 cm(-1)) is indicated in normal tissue and proteins (stronger amide I, red shifted DeltaCH2, broad and strong amide III, 1002, 1033, 1530, 1556 cm(-1)) are found in benign and malignant tissues. The major differences between benign and malignant tissue spectra are malignant tissues seem to have an excess of lipids (1082, 1301, 1440 cm(-1)) and presence of excess proteins (amide I, amide III, red shifted DeltaCH2, 1033, 1002 cm(-1)) is indicated in benign spectra. The multivariate statistical tool, principal components analysis (PCA) is employed for developing discrimination methods. A score of factor 1 provided a reasonable classification of all three tissue types. The analysis is further fine-tuned by employing Mahalanobis distance and spectral residuals as discriminating parameters. This approach is tested both retrospectively and prospectively. The limit test, which provides the most unambiguous discrimination, is also considered and this approach clearly discriminated all three tissue types. These results further support the efficacy of Raman spectroscopic methods in discriminating normal and diseased breast tissues.  相似文献   
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