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91.
Eight patients with diffuse panbronchiolitis (DPB) who had repeated intractable airway infections were continuously treated withNocardia rubra cell wall skeleton (N-CWS), a biological response modifier. As a result, subjective symptoms were reduced in 6 patients. Antibiotics therapy could be discontinued completely in two patients and the dose of antibiotics could be reduced considerably in two other patients. No adverse reactions in relation to N-CWS were observed. These results suggest that N-CWS is effective in treating erythromycin-resistant DPB.Abbreviations BRM Biological response modifier - DPB Diffuse panbronchiolitis - EM erythromycin - N-CWS Nocardia rubra cell wall skeleton  相似文献   
92.
农田林网中天空散射辐射的分布特征   总被引:2,自引:0,他引:2  
蔡天麟  高丽春 《生态学杂志》1991,10(2):29-31,35
一、引言森林生态系统是陆地生态系统的一个重要组成部分,它既可改善农业的生产条件,又可给人们提供良好的生活环境,是维持自然生态平衡的一个重要因素。在我国华北平原和沿海平原地区,林粮间作的方式可分为路林、沟渠林带网格的复合系统和混农林业系统,其中林木可起保持水土,防  相似文献   
93.
The methylation status of the nuclear DNA from a mealybug, aPlanococcus species, has been studied. Analysis of this DNA by High Performance Liquid Chromatography and Thin Layer Chromatography revealed the presence of significant amounts of 5-—methylcytosine. Since analysis of DNA methylation using the Msp I/Hpa II system showed only minor differences in susceptibility of the DNA to the two enzymes, it seemed possible that 5-methylcytosine (5mC) occurred adjacent to other nucleotides in addition to its usual position, next to guanosine. This was verified by dinucleotide analysis of DNA labelledin vitro by nick translation. These data show that the total amount of 5-methylcytosine in this DNA is slightly over 2.3 mol %, of which 0.61% occurs as the dinucleotide 5mCpG, 0.68% as 5mCpA, 0.59% as 5mCpT and 0.45% as 5mCpC. 5mCpG represents approximately 3.3% of all CpG dinucleotides. The experimental procedure would not have permitted the detection of 5mCp5mC, if it occurs in this system. Unusually high amounts of 6-methyladenine (approximately 4 mol %) and 7-methylguanine (approximately 2 mol %) were also detected, 6-methyladenine and 7-methylguanine occurred adjacent to all four nucleotides. The total G+C content was 33.7% as calculated from dinucleotide data and 32.9% as determined from melting profiles.  相似文献   
94.
The molecular, biochemical, and cellular characterization of EhGEF1 protein is described. Complete cDNA sequence of 1890 bp revealed an open reading frame that encodes a protein of 69 kDa. EhGEF1 is constituted of Dbl homology domain, pleckstrin homology domain, and several putative regulation sites. Studies of guanine nucleotide exchange activity of EhGEF1 on several GTPases from Entamoeba histolytica and Homo sapiens showed preferential activation on EhRacG, suggesting that EhGEF1 protein could be involved in mechanisms related to actin cytoskeleton activation, cytokinesis, capping, and uroid formation in trophozoite. Confocal microscopy studies of pExEhNeo/HSV-tagged-EhGEF1-transfected cells showed that trophozoites stimulated with ConA, EhGEF1, and EhRacG were localized at plasma membrane. Cellular studies showed that F-actin content of pExEhNeo/HSV-tagged-EhGEF1-transfected trophozoites as well as cellular migration and cell damage capacity were significantly altered. The observations suggest that EhRacG was the principal target of EhGEF1 and that EhGEF1 may provide a link between F-actin dynamics and EhRacG signaling.  相似文献   
95.
This paper reports on a case of massive hyperostotic alterations observed in the skeleton of an adult woman from the necropolis of Montescaglioso Belvedere (Basilicata, Southern Italy) attributed to the Enotrian culture and dated to the 6th century BC. Hyperostotic changes involve joints, the vertebral column, and the lower limbs. In particular, the large flowing ossification in both the thoracic (T6-T10) and lumbar (L2-L5) tracts, the sacralization of L5, accompanied by sacroiliac fusion on the left side, and the proliferative bone production on both the metaphyseal portion of the left tibia and the left third metatarsal are described. The vertebral antero-lateral ossification and the sacroiliac fusion support a diagnosis of diffuse idiopathic skeletal hyperostosis (DISH), while the flowing bone formation on the lower limbs supports a diagnosis of melorheostosis. The pathological conditions described here were already described in the literature, but this is the first reported case of the coexistence of DISH and the very rare melorheostosis. Furthermore, the skeleton from Montescaglioso Belvedere represents the first case of this disease described for ancient Europe, therefore adding a valuable contribution to the reconstruction of the antiquity and distribution of skeletal dysplasias.  相似文献   
96.
In the last years bioresorbable materials are gaining increasing interest for building implantable optical components for medical devices. In this work we show the fabrication of bioresorbable optical fibers designed for diffuse optics applications, featuring large core diameter (up to 200 μm) and numerical aperture (0.17) to maximize the collection efficiency of diffused light. We demonstrate the suitability of bioresorbable fibers for time‐domain diffuse optical spectroscopy firstly checking the intrinsic performances of the setup by acquiring the instrument response function. We then validate on phantoms the use of bioresorbable fibers by applying the MEDPHOT protocol to assess the performance of the system in measuring optical properties (namely, absorption and scattering coefficients) of homogeneous media. Further, we show an ex‐vivo validation on a chicken breast by measuring the absorption and scattering spectra in the 500–1100 nm range using interstitially inserted bioresorbable fibers. This work represents a step toward a new way to look inside the body using optical fibers that can be implanted in patients. These fibers could be useful either for diagnostic (e. g. for monitoring the evolution after surgical interventions) or treatment (e. g. photodynamic therapy) purposes. Picture : Microscopy image of the 100 μm core bioresorbable fiber.

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97.
Summary Fruit removal rates ofMyoporum acuminatum in a Queensland population were correlated with size of the ripe fruit crop throughout the season, but only sporadically correlated with nutritive contents of the fruits. Removal rates, as a proportion of crop size, varied synchronously among individuals and did not differ consistently among individuals with differing fruit traits. The principal avian consumer wasMeliphaga lewinii.  相似文献   
98.
99.
In additive manufacturing, or 3D printing, material is deposited drop by drop, to create micron to macroscale layers. A typical inkjet ink is a colloidal dispersion containing approximately ten components including solvent, the nano to micron scale particles which will comprise the printed layer, polymeric dispersants to stabilize the particles, and polymers to tune layer strength, surface tension and viscosity. To rationally and efficiently formulate such an ink, it is crucial to know how the components interact. Specifically, which polymers bond to the particle surfaces and how are they attached? Answering this question requires an experimental procedure that discriminates between polymer adsorbed on the particles and free polymer. Further, the method must provide details about how the functional groups of the polymer interact with the particle. In this protocol, we show how to employ centrifugation to separate particles with adsorbed polymer from the rest of the ink, prepare the separated samples for spectroscopic measurement, and use Diffuse Reflectance Fourier Transform Infrared Spectroscopy (DRIFTS) for accurate determination of dispersant/particle bonding mechanisms. A significant advantage of this methodology is that it provides high level mechanistic detail using only simple, commonly available laboratory equipment. This makes crucial data available to almost any formulation laboratory. The method is most useful for inks composed of metal, ceramic, and metal oxide particles in the range of 100 nm or greater. Because of the density and particle size of these inks, they are readily separable with centrifugation. Further, the spectroscopic signatures of such particles are easy to distinguish from absorbed polymer. The primary limitation of this technique is that the spectroscopy is performed ex-situ on the separated and dried particles as opposed to the particles in dispersion. However, results from attenuated total reflectance spectra of the wet separated particles provide evidence for the validity of the DRIFTS measurement.  相似文献   
100.
Biotinidase deficiency is an autosomal recessive disorder of biotin metabolism leading to varying degrees of neurologic and cutaneous symptoms when untreated. In the present study, we report the clinical features and the molecular investigation of biotinidase deficiency in four unrelated consanguineous Algerian families including five patients with profound biotinidase deficiency and one child characterized as partial biotinidase deficiency. Mutation analysis revealed three novel mutations, c.del631C and c.1557T>G within exon 4 and c.324-325insTA in exon 3. Since newborn screening is not available in Algeria, cascade screening in affected families would be very helpful to identify at risk individuals.  相似文献   
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