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1.
Seven enrichment media (two proposed by the authors) for detecting salmonellas from polluted freshwater were compared. The Most Probable Number technique for enumeration of salmonellas in water samples was used, directly adding filtered water to buffered peptone water as the pre-enrichment medium. The results indicate that Rappaport-Vassiliadis/43 and Rappaport-Vassiliadis/43 supplemented with 10 micrograms of sodium novobiocin per ml are the best media for the recovery and enumeration of salmonellas from water samples.  相似文献   
2.
Seven enrichment media (two proposed by the authors) for detecting salmonellas from polluted freshwater were compared. The Most Probable Number technique for enumeration of salmonellas in water samples was used, directly adding filtered water to buffered peptone water as the pre-enrichment medium. The results indicate that Rappaport-Vassiliadis/43 and Rappaport-Vassiliadis/43 supplemented with 10 μg of sodium novobiocin per ml are the best media for the recovery and enumeration of salmonellas from water samples.  相似文献   
3.
Unpredictable growth pattern of costochondral graft.   总被引:6,自引:0,他引:6  
B Guyuron  C I Lasa 《Plastic and reconstructive surgery》1992,90(5):880-6; discussion 887-9
Costochondral grafts have gained increasing popularity in reconstruction of the temporomandibular joint and condyle in children. This is a report on the long-term follow-up of eight adolescent patients who underwent reconstruction of the temporomandibular joint and ramus for correction of hemifacial microsomia or trauma-related temporomandibular joint ankylosis during varying periods of growth. Six patients had hemifacial microsomia, and two suffered from posttraumatic temporomandibular joint ankylosis. Average follow-up was 80.4 months. Four patients had excessive growth of the graft, one patient had suboptimal growth, and three patients had no growth. In addition, one patient had undergone four procedures for significant graft overgrowth. Based on this study and review of the literature, we have concluded that the growth pattern of the costochondral graft is extremely unpredictable, ankylosis is a common problem following a temporomandibular joint reconstruction with costochondral graft, and mandibular overgrowth on the grafted site can actually be more troublesome than the lack of growth. Furthermore, maxillary growth is proportionately influenced by vertical mandibular growth of the graft, while the horizontal maxillary growth is not altered. Ankylosis is a result of ossification of the cartilaginous portion and the three-dimensional graft overgrowth, aggressively extending beyond the cartilage graft boundary. Based on this study, we recommend that this procedure be performed only on severe deficiencies. Adequate amounts of soft tissue should be retained between the skull base and the graft, and we further recommend harvesting the graft from the fourth or fifth rib, which may reduce the potential for overgrowth.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
4.
Quercetin 3-rutinoside, quercetin 3-α-l-rhamnoside, 7,4′-dimethylquercetin 3-rutinoside and the novel glycoside 7,4′-dimethylquercetin 3-rutinoside-5-glucoside have been identified from aerial parts of Erythroxylon argentinum.  相似文献   
5.
The study of natural hybrid zones can illuminate aspects of lineage divergence and speciation in morphologically cryptic taxa. We studied a hybrid zone between two highly divergent but morphologically similar lineages (south‐western and south‐eastern) of the Iberian endemic Bosca's newt (Lissotriton boscai) in SW Iberia with a multilocus dataset (microsatellites, nuclear and mitochondrial genes). STRUCTURE and NEWHYBRIDS analyses retrieved few admixed individuals, which classified as backcrosses involving parental individuals of the south‐western lineage. Our results show asymmetric introgression of mtDNA beyond the contact from this lineage into the south‐eastern lineage. Analysis of nongeographic introgression patterns revealed asymmetries in the direction of introgression, but except for mtDNA, we did not find evidence for nonconcordant introgression patterns across nuclear loci. Analysis of a 150‐km transect across the hybrid zone showed broadly coincident cline widths (ca. 3.2–27.9 km), and concordant cline centres across all markers, except for mtDNA that is displaced ca. 60 km northward. Results from ecological niche modelling show that the hybrid zone is in a climatically homogenous area with suitable habitat for the species, suggesting that contact between the two lineages is unlikely to occur further south as their distributions are currently separated by an extensive area of unfavourable habitat. Taken together, our findings suggest the genetic structure of this hybrid zone results from the interplay of historical (biogeographic) and population‐level processes. The narrowness and coincidence of genetic clines can be explained by weak selection against hybrids and reflect a degree of reproductive isolation that is consistent with cryptic speciation.  相似文献   
6.
In the context of radiotherapy, collateral effects of ablative doses of ionizing radiation (AIR) on stromal components of tumors remains understudied. In this work, cancer-associated fibroblasts (CAFs) isolated from freshly resected human lung tumors were exposed to AIR (1x 18 Gy) and analyzed for their release of paracrine factors. Inflammatory mediators and regulators of angiogenesis and tumor growth were analyzed by multiplex protein assays in conditioned medium (CM) from irradiated and non-irradiated CAFs. Additionally, the profile of secreted proteins was examined by proteomics. In functional assays, effects of CAF-CM on proliferative and migratory capacity of lung tumor cells (H-520/H-522) and human umbilical vein endothelial cells (HUVECs) and their tube-forming capacity were assessed. Our data show that exposure of CAFs to AIR results in 1) downregulated release of angiogenic molecules such as stromal cell-derived factor-1, angiopoietin, and thrombospondin-2 (TSP-2); 2) upregulated release of basic fibroblast growth factor from most donors; and 3) unaffected expression levels of hepatocyte growth factor, interleukin-6 (IL-6), IL-8, IL-1β, and tumor necrosis factor-α. CM from irradiated and control CAFs did not affect differently the proliferative or migratory capacity of tumor cells (H-520/H-522), whereas migratory capacity of HUVECs was partially reduced in the presence of irradiated CAF-CM. Overall, we conclude that AIR mediates a transformation on the secretory profile of CAFs that could influence the behavior of other cells in the tumor tissue and hence guide therapeutic outcomes. Downstream consequences of the changes observed in this study merits further investigations.  相似文献   
7.
International Journal of Primatology - Intergroup encounters are common in nonhuman primates and can vary from affiliative to aggressive. We extracted data from the literature to test five...  相似文献   
8.
We reported previously that the expression of Wnt-related genes is lower in osteoporotic hip fractures than in osteoarthritis. We aimed to confirm those results by analyzing β-catenin levels and explored potential genetic and epigenetic mechanisms involved.  相似文献   
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