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81.
Widespread morbidity and mortality of Juglans nigra has occurred in the western USA over the past decade. Tree mortality is the result of aggressive feeding by the walnut twig beetle (Pityophthorus juglandis) and subsequent canker development around beetle galleries caused by a filamentous ascomycete in genus Geosmithia (Ascomycota: Hypocreales). Thirty-seven Geosmithia strains collected from J. californica, J. hindsii, J. major and J. nigra in seven USA states (AZ, CA, CO, ID, OR, UT, WA) were compared with morphological and molecular methods (ITS rDNA sequences). Strains had common characteristics including yellowish conidia en masse, growth at 37 C and absence of growth on Czapek-Dox agar and belonged to a single species described here as G. morbida. Whereas Geosmithia are common saprobes associated with bark beetles attacking hardwoods and conifers worldwide, G. morbida is the first species documented as a plant pathogen.  相似文献   
82.
An industrial Penicillium chrysogenum strain was transformed using two dominant selection markers, namely the bacterial gene for phleomycin resistance (ble) fused to a fungal promoter, and the acetamidase (amdS) gene from Aspergillus nidulans. Transformation frequencies of up to 20 transformants per microgram of DNA were obtained with the ble system. With the amdS marker the frequency was up to 120 transformants. Cotransformation was very efficient when using amdS as a selection marker. The introduction of pAN5-41B, a plasmid carrying the Escherichia coli lacZ gene fused to the strong glyceraldehyde-3-phosphate dehydrogenase gene (gpd) promoter from A. nidulans, resulted in the formation of blue colonies on XGal plates indicating expression of the lacZ fusion gene in P. chrysogenum. A more detailed analysis of expression levels in several transformants showed that up to 6% of the total amount of soluble protein consists of the beta-galactosidase fusion protein.  相似文献   
83.
BACKGROUND: Expression of the nuclear steroid hormone receptors (SHR) within certain parts of the human brain has been described by many authors. However, a comprehensive analysis of SHR expression in the human brain still has not been performed. AIM: To investigate the expression of SHR in different anatomical areas of the brain, especially within the neocortex. METHOD: Immunohistochemical expression of estrogen receptors (ER), progesterone receptors (PR) and androgen receptors (AR) in different regions of the human brain was examined. RESULTS: Nuclear expression of the AR was found in the mamillary body, praecentral gyrus and hippocampus of males. The same expression in analysed structures of female was not found. The expression of ER and PR was not observed. CONCLUSIONS: The analysis revealed unexpected localization of SHR within the brain cortex, which could be the first step to the explanation of SHR action in brain as an interrelationship to function and behaviour. These results indicate on the possibility of SHR detection in post-mortal brain.  相似文献   
84.
Aim: Vacuum-assisted closure (VAC) was primarily designed for the treatment of pressure ulcers or chronic, debilitating wounds. Recently, VAC has become an encouraging treatment modality for sternal wound infection after cardiac surgery, providing superior results to conventional treatment strategies. Methods: From November 2004 to September 2006, 34 patients, undergoing VAC therapy for sternal wound infection following cardiac surgery, were prospectively evaluated. Ten patients (29 %) were treated for superficial sternal wound infection and 24 (71 %) for deep sternal wound infection. The median age was 69.9 years (range 48 to 82) and the median BMI was 33.4 kg/m(2) (range 28 to 41). Twenty patients (59 %) were women and 19 patients (59 %) were diabetics. Owing to sternal wound infection complications, 16 patients (47 %) were readmitted to the department. VAC was used following the previous failure of the conventional treatment strategy in 7 patients (21 %). Results: Thirty-three patients (97 %) were treated successfully. One patient (3 %) died of multiple organ failure. The overall length of hospitalization was 34.6 days (range 9 to 62). The median number of dressing changes was 4.6 (range 3 to 10). The median VAC treatment time until surgical closure was 9.2 days (range 6 to 21 days). VAC therapy was solely used as a bridge to definite wound closure. Three patients (9 %) with chronic fistula were re-admitted 1 to 6 months after VAC therapy. Conclusions: VAC therapy is a safe and reliable option in the treatment of sternal wound infection in cardiac surgery. VAC therapy should be considered an effective adjunct to conventional treatment modalities for the treatment of extensive and life-threatening wound infections following cardiac surgery, particularly in the presence of risk factors.  相似文献   
85.
Ammonia released during organic matter mineralization is converted during nitrification to nitrate. We followed spatiotemporal dynamics of the nitrifying microbial community in deep oligotrophic Lake Constance. Depth-dependent decrease of total ammonium (0.01–0.84 μM) indicated the hypolimnion as the major place of nitrification with 15N-isotope dilution measurements indicating a threefold daily turnover of hypolimnetic total ammonium. This was mirrored by a strong increase of ammonia-oxidizing Thaumarchaeota towards the hypolimnion (13%–21% of bacterioplankton) throughout spring to autumn as revealed by amplicon sequencing and quantitative polymerase chain reaction. Ammonia-oxidizing bacteria were typically two orders of magnitude less abundant and completely ammonia-oxidizing (comammox) bacteria were not detected. Both, 16S rRNA gene and amoA (encoding ammonia monooxygenase subunit B) analyses identified only one major species-level operational taxonomic unit (OTU) of Thaumarchaeota (99% of all ammonia oxidizers in the hypolimnion), which was affiliated to Nitrosopumilus spp. The relative abundance distribution of the single Thaumarchaeon strongly correlated to an equally abundant Chloroflexi clade CL500-11 OTU and a Nitrospira OTU that was one order of magnitude less abundant. The latter dominated among recognized nitrite oxidizers. This extremely low diversity of nitrifiers shows how vulnerable the ecosystem process of nitrification may be in Lake Constance as Central Europe's third largest lake.  相似文献   
86.
87.
1. Interstitial bacterial abundance, production and ectoenzyme activity were investigated over an annual cycle in an Austrian river when infiltration of oligotrophic river water into a river-bank was artificially enhanced. These microbial parameters were related to porewater chemistry and the concentration of particulate (POC) and dissolved organic carbon (DOC).
2. Porewater chemistry reflected the hydrodynamic mixing of infiltrating river water with riparian groundwater. Seasonal fluctuations in the microbial parameters resulted mainly from changes in temperature and organic matter supply. Seasonal change in porewater chemistry in the river-bank was detectable laterally only within the first metre of the sediment and decreased rapidly with increasing distance from the sediment–water interface.
3. The DOC concentration decreased only slightly during lateral transport through the aquifer, while total organic carbon (TOC) concentration as well as abundance and activity of interstitial bacteria were reduced by up to one order of magnitude within the top metre of the sediment. Retention of incoming particulate matter structured the lateral distribution pattern of TOC concentration. The POC and not the DOC pool was the main source of carbon for interstitial bacteria and, therefore, the quality of POC determines the distribution of microbial metabolism within the riparian zone.  相似文献   
88.
BackgroundHigh prevalence of type 2 diabetes mellitus (T2DM) is associated with a higher prevalence of acute coronary syndrome (ACS). Inflammation is one of the important contributors to the pathogenesis and complications of coronary atherosclerotic plaque. Growth Differentiation Factor-15 (GDF-15) and Tenascin-C (TNC) play an important role in the initiation of atherosclerotic plaque as well as its rupture. The aim of the study was to evaluate the association between serum GDF-15, TNC, and the risk of ACS among T2DM patients.MethodsAnthropometric parameters, routine biochemical investigations like liver and renal function tests, lipid profile, and Creatine Kinase-Total (CK-T), Creatine Kinase-MB (CK-MB) were measured in 42 T2DM patients with ACS and 42 T2DM patients. Serum GDF-15 and TNC were measured by Human Sandwich-ELISA kits.ResultsSerum GDF-15 and TNC levels were significantly higher in T2DM patients with ACS as compared to T2DM patients. Serum GDF-15 was significantly correlated with waist circumference, diastolic blood pressure, pulse, serum CK-T, and CK-MB. Serum TNC was significantly correlated with the pulse, serum CK-T, CK-MB, high-density lipoprotein-cholesterol, and blood urea nitro GEN. Multivariate linear regression analysis showed that waist circumference was independently positively associated with serum GDF-15.ConclusionsT2DM patients with higher serum GDF-15 and TNC levels were at higher risk of acute coronary syndrome independent of other cardiovascular risk factors.  相似文献   
89.
Peripheral nerve stimulation (PNS) is a neurostimulation analgesic technique. PNS is utilized to treat peripheral neuropathic pain. It is highly sophisticated and a specialized technique used where other forms of treatment have failed. This paper describes the PNS procedure, its therapeutic principles, indications, and the comprehensive care for patients after the PNS implant. First, we summarize our experience using this type of invasive treatment. In the second part, a case of intractable neuropathic pain following repeated surgery to the ulnar nerve is reported. Prior to PNS, the patient underwent multiple types of antineuralgic treatment with no significant result. Only after the PNS application, was a significant analgesic effect achieved.  相似文献   
90.
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