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101.
In-canopy mixing ratio gradients and above-canopy fluxes of several volatile organic compounds (VOCs) were measured using a commercial proton transfer reaction mass spectrometer (PTR-MS) in a European beech (Fagus sylvatica) forest in Denmark. Fluxes of methanol were bidirectional: Emission occurred during both day and night with highest fluxes (0.2 mg C m−2 h−1) during a warm period; deposition occurred dominantly at daytime. Confirming previous branch-level measurements on beech, the forest’s monoterpene emissions (0–0.5 mg C m−2 h−1), and in-canopy mixing ratios showed a diurnal cycle consistent with light-dependent emissions; a result contrasting temperature-only driven emissions of most conifer species. Also emitted was acetone, but only at ambient temperatures exceeding 20°C. Slow deposition dominated at lower temperatures. Our in-canopy gradient measurements contrast with earlier results from tropical and pine forest ecosystems in that they did not show this beech ecosystem to be a strong sink for oxygenated VOCs (OVOCs). Instead, their gradients were flat and only small deposition velocities (<0.2 cm s−1) were observed to the onsite soil. However, as methanol soil uptake was consistent and possibly related to soil moisture, more measurements are needed to evaluate its soil sink strength. In turn, as canopy scale fluxes are net fluxes with stomatal emissions from photosynthesizing leaves potentially affecting non-stomatal oxygenated VOC uptake, only independent, controlled laboratory experiments may be successful in separating gross fluxes.  相似文献   
102.
Bacteria were isolated from the mycelial surface of Pleurotus ostreatus and their role in fruiting body induction (fructification) of the edible mushroom P. ostreatus was investigated. Analysis of the bacterial community that colonized the mycelium showed that the species composition and numbers of culturable bacteria differed according to the developmental stage of P. ostreatus. In particular, the population size of fluorescent pseudomonads increased during fruiting body induction. An experiment showed that inoculation of pure cultures of the mycelium with strains of fluorescent Pseudomonas spp. isolated from the mycelial plane of commercially produced mushrooms promoted the formation of primordia and enhanced the development of the basidiome of P. ostreatus. Results of this research strongly suggest that inoculation of the mycelium with specific bacteria may have beneficial applications for mushroom production.  相似文献   
103.
104.
Glass slide arrayed with fosmid clone DNAs generated from swine feces as probes were fabricated and used as a metagenome microarray (MGA). MGA appeared to be specific to their corresponding target genomic fragments. The detection limit was 10 ng of genomic DNA (ca. 10(6) bacterial cells) in the presence of 1000 ng of background DNA. Linear relationships between the signal intensity and the target DNA (20-100 ng) were observed (r ( 2 )=0.98). Application of MGA to the comparison of swine fecal metagenomes suggested that the microbial community composition of swine intestine could be dependent on the health state of swine.  相似文献   
105.
The CC chemokine receptor 7 (CCR7) and cognate CCR7 ligands, CCL19 and CCL21, help establish microenvironments in lymphoid tissue that can facilitate encounters between naive T cells and mature dendritic cells (DCs). This study was conducted to determine if CCR7 ligands can augment the immunogenicity of a DNA vaccine that expresses glycoprotein B (gB) of the pseudorabies virus (PrV). The genetic co-transfer of CCR7 ligands along with a PrV DNA vaccine increased the levels of serum PrV-specific immunoglobulin (Ig) G by 2- to 2.5-fold. In addition, the level of PrV-specific IgG2a isotype was significantly enhanced by co-injection of CCR7 ligand DNA, which indicates that CCR7 ligand biases the humoral immunity toward the Th1-type pattern. The co-injection of CCR7 ligand DNA consistently enhanced the level of Th1-type cytokines (IL-2 and IFN-gamma) produced by stimulated immune cells when compared with a group that was vaccinated with the PrV DNA vaccine. Also, the genetic co-transfer of CCR7 ligand DNAs with PrV DNA vaccine provided prolonged survival against a virulent challenge by PrV. Moreover, the co-administration of CCR7 ligand DNA increased the number of mature DCs into the secondary lymphoid tissues, which appeared to enhance the proliferation of PrV-immune CD4(+) T cells. Taken together, these findings indicate that CCR7 ligands are an attractive adjuvant for a PrV DNA vaccine that can offer protective immunity against the PrV.  相似文献   
106.
Universal infantile hepatitis B virus (HBV) vaccination may lead to an increase in vaccine escape variants, which may pose a threat to the long-term success of massive vaccination. To determine the prevalence of occult infections in Korean vaccinated individuals, 87 vaccinated subjects were screened for the presence of HBV DNA using both the nested PCR protocol and the VERSANT HBV DNA 3.0 assay. The mutation patterns of variants were analyzed in full-length HBV genome sequences. Their HBsAg secretion and replication capacities were investigated using both in vitro transient transfection and in vivo hydrodynamic injection. The presence of HBV DNA was confirmed in 6 subjects (6.9%). All six variants had a common mutation type (X8Del) composed of an 8-bp deletion in the C-terminal region of the HBV X gene (HBxAg). Our in vitro and in vivo analyses using the full-length HBV genome indicated that the X8Del HBxAg variant reduced the secretion of HBsAg and HBV virions compared to the wild type. In conclusion, our data suggest that a novel mutation (X8Del) may contribute to occult HBV infection in Korean vaccinated individuals via a reduced secretion of HBsAg and virions, possibly by compromising HBxAg’s transacting capacity.  相似文献   
107.
Kim A  Lee J  Choi JS  Won NH  Koo BH 《Acta cytologica》2000,44(3):361-367
OBJECTIVE: To evaluate the accuracy of fine needle aspiration cytology (FNAC) of the breast at our institution and to perform quality assurance. STUDY DESIGN: Two hundred forty-six cases with pathologic confirmation were selected and reviewed. A pathologist performed most of the aspirations at an outpatient breast clinic. We correlated cytologic and histologic findings and evaluated the influence of the size, location, grade, and pathologic subtypes and fibrosis in breast lesions on diagnostic results. RESULTS: The likelihood ratios for malignant, suspicious, atypical, benign and unsatisfactory cytologic diagnoses were 98.71, 5.48, 1.09, 0.07 and 0.55, respectively. The absolute and complete sensitivities for malignant lesions were 64.5% and 90.3%, respectively. The specificity was 71.9%. False negative and positive rates were 4.3% and 0.7%, respectively. The predictive value for a malignant cytologic diagnosis was 98.4%. The rate of unsatisfactory samples was 9.3%. The rate of concordance between cytologic and histologic diagnosis was lower for large and diffusely growing lesions (benign and malignant), for malignancies with abundant fibrosis and of unusual types and for carcinomas of low grade. All axillary and recurrent chest wall lesions were diagnosed cytologically. Cell block sections were useful in a small number of cases. CONCLUSION: Understanding the performance and limitations of FNAC can enhance its value as a diagnostic technique in the management of breast disease.  相似文献   
108.

Objective

To analyze trends in the use of partial nephrectomy, we evaluated which individual factors of renal nephrometry score (RNS) influenced the operative approach bi-annually from 2008 to 2014.

Materials and Methods

We performed a retrospective review of renal cell carcinoma treated by surgery in 2008, 2010, 2012, and 2014. The complexity of renal masses was measured using the R.E.N.A.L. nephrometry scoring system with CT or MRI. Group comparison in terms of operation year and surgical type (partial nephrectomy versus radical nephrectomy) was performed. We developed a nomogram to quantitate the likelihood of selecting partial nephrectomy over radical nephrectomy.

Results

A total of 1106 cases (237 in 2008, 225 in 2010, 292 in 2012, and 352 in 2014) were available for the study. Over the study period, the proportion of partial nephrectomies performed increased steadily from 21.5% in 2008 to 66.5% in 2014 (p < 0.05). Furthermore, use of partial nephrectomy increased steadily in all RNS complexity groups (low, moderate, and high) (p < 0.05). In the analysis of individual components of RNS, values of the R and N components increased statistically by year in the partial nephrectomy group (p < 0.05). Average AUC was 0.920.

Conclusions

The proportion of partial nephrectomies performed sharply increased over the study period. Additionally, over the study period, more partial nephrectomies were performed for renal masses of larger size and closer to the collecting system and main renal vessels. A nomogram developed based on this recent data set provides significant predictive value for surgical decision making.  相似文献   
109.
Systemic lupus erythematosus (SLE) is a systemic autoimmune disease characterized by both population and phenotypic heterogeneity. Our group previously identified linkage to SLE at 4p16 in European Americans (EA). In the present study we replicate this linkage effect in a new cohort of 76 EA families multiplex for SLE by model-free linkage analysis. Using densely spaced microsatellite markers in the linkage region, we have localized the potential SLE susceptibility gene(s) to be telomeric to the marker D4S2928 by haplotype construction. In addition, marker D4S394 showed marginal evidence of linkage disequilibrium with the putative disease locus by the transmission disequilibrium test and significant evidence of association using a family-based association approach as implemented in the program ASSOC. We also performed both two-point and multipoint model-based analyses to characterize the genetic model of the potential SLE susceptibility gene(s), and the lod scores both maximized under a recessive model with penetrances of 0.8. Finally, we performed a genome-wide scan of the total 153 EA pedigrees and evaluated the possibility of interaction between linkage signals at 4p16 and other regions in the genome. Fourteen regions on 11 chromosomes (1q24, 1q42, 2p11, 2q32, 3p14.2, 4p16, 5p15, 7p21, 8p22, 10q22, 12p11, 12q24, 14q12, 19q13) showed evidence of linkage, among which, signals at 2p11, 12q24 and 19q13 also showed evidence of interaction with that at 4p16. These results provide important additional information about the SLE linkage effect at 4p16 and offer a unique approach to uncovering susceptibility loci involved in complex human diseases.  相似文献   
110.
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