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1.
This is a comparative study of uptake of trimethoprim from 1) fresh water, 2) salt water after 7 days of adaption and 3) salt water without previous adaptation. The rate and extent of absorption were found to vary significantly. The salt water adapted group reached a plasma concentration of approx. 1 µg/ml after 10 h, the unadapted salt water group after 24 to 48 h and the fresh water group did not reach this concentration. The results are discussed in relation to the non-ionic diffusion theory and to the alterations taking place in euryhaline species of fish during adaptation to salt water.  相似文献   
2.

Background  

In a project to determine the causes of winter mortality in reindeer in Finnmark County, northern Norway, the most frequent diagnosis turned out to be complete emaciation, despite several of the reindeer having been given silage for up to 4 weeks before they died. The present paper describes autopsy results and other findings in these animals.  相似文献   
3.

Background

The oncogenesis of ovarian cancer is poorly understood. The aim of this study was to identify mRNAs differentially expressed between moderately and poorly differentiated (MD/PD) serous ovarian carcinomas (SC), serous ovarian borderline tumours (SBOT) and superficial scrapings from normal ovaries (SNO), and to correlate these mRNAs with clinical parameters including survival.

Methods

Differences in mRNA expression between MD/PD SC, SBOT and SNO were analyzed by global gene expression profiling (n = 23), validated by RT-qPCR (n = 41) and correlated with clinical parameters.

Results

Thirty mRNAs differentially expressed between MD/PD SC, SBOT and SNO were selected from the global gene expression analyses, and 21 were verified (p<0.01) by RT-qPCR. Of these, 13 mRNAs were differentially expressed in MD/PD SC compared with SNO (p<0.01) and were correlated with clinical parameters. ZNF385B was downregulated (FC = −130.5, p = 1.2×10−7) and correlated with overall survival (p = 0.03). VEGFA was upregulated (FC = 6.1, p = 6.0×10−6) and correlated with progression-free survival (p = 0.037). Increased levels of TPX2 and FOXM1 mRNAs (FC = 28.5, p = 2.7×10−10 and FC = 46.2, p = 5.6×10−4, respectively) correlated with normalization of CA125 (p = 0.03 and p = 0.044, respectively). Furthermore, we present a molecular pathway for MD/PD SC, including VEGFA, FOXM1, TPX2, BIRC5 and TOP2A, all significantly upregulated and directly interacting with TP53.

Conclusions

We have identified 21 mRNAs differentially expressed (p<0.01) between MD/PD SC, SBOT and SNO. Thirteen were differentially expressed in MD/PD SC, including ZNF385B and VEGFA correlating with survival, and FOXM1 and TPX2 with normalization of CA125. We also present a molecular pathway for MD/PD SC.  相似文献   
4.
To evaluate the role of seafoods in the epidemiology of human listeriosis and the role of the processing environment as a source of Listeria monocytogenes in seafood products, 305 L. monocytogenes isolates were characterized by multilocus enzyme electrophoresis using 21 genetic loci and restriction enzyme analysis of total DNA. Forty-four isolates were recovered from patients in Norway; 93 were isolated from seafoods, seafood-processing environments, and seawater from 55 different producers; and the remaining 168 isolates originated from six seafood-processing plants and one transport terminal examined in detail for L. monocytogenes. The patient isolates fell into 11 electrophoretic types, with four of them being responsible for 77% of the listeriosis cases in 1992 to 1996. Isolates from Norwegian seafoods and processing environments showed great genetic diversity, indicating that seafoods and seafood-processing environments do not offer a niche for specific L. monocytogenes strains. On the other hand, isolates from individual processing plants were genetically more homogenous, showing that plants are likely to be colonized with specific subclones of L. monocytogenes. The isolation of identical subclones of L. monocytogenes from both human patients and seafoods, including ready-to-eat products, suggests that such products may have been possible sources for listeriosis cases in Norway.  相似文献   
5.
Lipopolysaccharides (LPS) from Legionella bozemanii serogroup 1 and Legionella longbeachae serogroup 1 were subjected to chemical analyses. The lipid A part of both LPSs contained 2,3-dideoxy-2,3-diamino-d-glucose as major constituents and d-glucosamine and glycerol as minor constituents of the sugar backbone structure. Both LPSs exhibited a very complex fatty acid composition. Twenty amide-linked 3-hydroxy fatty acids were detected in LPS of L. longbeachae, whereas seventeen were encountered in LPS of L. bozemanii. Both LPSs contained nine ester-linked nonhydroxy fatty acids and the unique long-chain fatty acids 27-oxo-octacosanoic acid, 29-oxotriacontanoic acid, heptacosane-1,27-dioic acid and nonacosane-1,29-dioic acid. SDS-PAGE showed that L. bozemanii produced smooth-form LPS, whereas L. longbeachae LPS was mainly of the R-type. Composition analyses were in accordance with these electrophoretic patterns. d-Quinovosamine and l-fucosamine constituted 80 mol% of the polysaccharide part of L. bozemanii LPS. Other sugars identified were d-glucosamine, d-mannose, d-glucose, l-rhamnose, d-glycero-d-manno-heptose, l-glycero-d-mannoheptose, 2-keto-3-deoxy-octonic acid and glycerol. The polysaccharide chain from LPS of L. longbeachae appeared to be shorter, but composed of the same sugars except l-fucosamine. Both LPSs contained glycerol phosphate and glucosamine phosphate and L. longbeachae LPS contained in addition glucose phosphate.Abbreviations EI Electron impact - GlcN3N 2,3-Diamino-2,3-dideoxy-d-glucose - HPAEC High pH anion-exchange chromatography - Kdo 2-Keto-3-deoxy-octonic acid - LPS Lipopolysaccharide - PCP Phenol/chloroform/petroleum ether solvent - PED Pulsed electrochemical detection - PS Polysaccharide - TFA Trifluoroacetyl - TMS Trimethylsilyl  相似文献   
6.
The complement component C3 was isolated from spotted wolffish (Anarhichas minor Olafsen) serum by polyethylene glycol precipitation, anion exchange chromatography and gel filtration. Silver staining in SDS-PAGE and rabbit anti-wolffish C3 antiserum used in Western blotting revealed that spotted wolffish C3 contains two polypeptide chains, M(r)65 and 115kDa, respectively. The high molecular weight alpha-chain of the C3 incorporated 14C-methylamine suggesting that it contained a reactive thioester group. The deduced amino acid sequence, after screening a liver cDNA expression library, showed that the wolffish C3 contained key amino acids for binding C3 convertase, factor H, I and properdin. Also, high degree of homology to other vertebrate C3 was found in the beta-alpha junction site. Phylogenetic tree analysis indicated that the Japanese flounder and spotted wolffish that belong to order pleuronectiformes and perciformes, respectively, are phylogenetically close species. Immunohistochemical experiments showed that liver hepatocytes and blood contained C3, and in situ hybridisation experiments revealed that liver hepatocytes expressed C3.  相似文献   
7.
8.
The function of the cytochrome b559, a Photosystem II (PS II) reaction center ubiquitous component is not yet known. Cytochrome b559appears in a high (HP) or low (LP) potential form. The HP form is converted into the LP form during aerobic photoinhibition. It has been proposed before that this conversion, assumed to be reversible, ascribes protection against light stress of PS II by redirecting electron flow within PS II thus avoiding charge recombination of the primary radical pair and related oxidative damage. Here, we have used an experimental system allowing to assay the relation between the cytochrome b559redox potential shift, its reversibility and protection against light induced PS II inactivation. Under anaerobic conditions fast reversible photoinactivation of PS II in isolated spinach thylakoids is observed accompanied by monomerisation of PS II. Monomers did not dissociate further into PS II sub-particles and did not migrate out of the grana partitions as observed in aerobic photoinactivation. The anaerobic photoinactivation is accompanied by an increase in the cytochrome b559LP/HP ratio. However, despite recovery of PS II activity and partially of its dimeric form in darkness under aerobic conditions, no reversal of the cytochrome b559redox potential shift accompanied these processes. Re-exposure of reactivated thylakoids having an increased PS II population in the LP form of the cytochrome b559to strong illumination under aerobic conditions, did not result in a measurable protection of PS II as compared to control thylakoids. While it is possible that cytochrome b559may play a protective role against light stress in PS II, the results presented here do not indicate that the increase in the ratio LP/HP form is involved in this process.  相似文献   
9.
Amyotrophic lateral sclerosis (ALS) and parkinsonism-dementia complex (PDC) are neurodegenerative disorders that occurred with extremely high frequency among the native population on Guam, especially in the 1950s and 1960s, but have substantially declined over the last half-century. The etiology of these diseases is unknown, but the most plausible hypothesis centers on imbalances in essential and toxic metals. We have determined the concentrations of Cd, Co, Cu, Fe, Mn, Rb, V, and Zn in formalin-fixed brain tissue collected during the period 1979–1983 from eight Guamanian patients with ALS, four with PDC, and five control subjects using high-resolution inductively coupled plasma-mass spectrometry. The concentrations of Cd are markedly and significantly elevated both in gray and white matter in ALS, but not in PDC patients. The concentrations of Zn are elevated for both patient groups, in both gray and white matter, but only the difference in gray matter for PDC is significant. For the other metals, no significant differences are found.  相似文献   
10.
OBJECTIVE: To evaluate the intraoperative imprint diagnoses of smears from sentinel lymph nodes that had been primary screened by cytotechnologists and to assess the most important causes of false negative (FN) imprint diagnoses. STUDY DESIGN: Material consisted of 429 imprints from sentinel lymph nodes in 211 breast cancer patients that were sent for frozen section examination over 13 months. RESULTS: The mean number of imprints/lymph nodes per patient was 2.02. The mean screening time per imprint was 3.6 minutes. Sixty-six sentinel nodes (16%) from 51 women (24%) were metastatic. Imprints and/or frozen sections were positive in 54 nodes (82%). Imprints were positive in 38 nodes, representing 70% of intraoperative positive nodes and 58% of the total number of positive nodes. Twenty-six of 28 (93%) FN imprints were due to suboptimal sampling. Four of 9 FN macrometastases did not contain diagnostic or suspicious cells/cell groups even on rescreening, whereas a few, and then only 1 diagnostic group were identified in 2/9. There were no false positives. CONCLUSION: Primary screening by experienced cytotechnologists is both rapid and reliable and enabled the diagnosing pathologist to concentrate on the frozen section. The major cause of false negative imprints is sampling, even in macrometastases.  相似文献   
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