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171.
Lime-trees (Tilia begonifolia Stev.) have countless ecological and economical values in the northern forests of Iran. Bole wounds on residual trees are commonly caused by logging. The healing ability of bole wounds and the effect of bole wounds on diameter growth in lime-trees were assessed in a natural mixed uneven-age stand. The susceptibility to decay in relation to the wound severity was also evaluated. Condition and location of lime-trees before and after selective logging were determined through systematic plot sampling. The position of each lime-tree was identified on a topographical map using the global positioning system. After 10 years from wound occurrence, tree and wound characteristics were also re-measured. Overall, 68 stems (9.7 stem ha?1) of lime-trees were found in the sampled area, 25 stems (36.8%) were damaged in the form of bole wound, and 43 stems (63.2%) were undamaged. Statistical differences between wounded or non-wounded lime-trees in terms of diameter and height were not found. Most of the wounds occurred at the height of < 1 m; the average wound size was 370.5 cm2. Wound severity was related to wound size and wound position. Wound width healing rate was 6.2 mm year?1. The wound shape was found to be a healing factor as the healing rate by width was higher than that by length. Healed wounds were only 12, 60% of bole wounds resulted in decay. Diameter growth of wounded trees was 43.5% lower than undamaged trees. The average annual diameter growth decreased by increasing wound severity. The results indicated the lime-tree is a very sensitive species to damage caused by logging (bole wound). Single-tree selection cutting needs more careful logging operations to reduce damage on residual lime-trees in order to safeguard this species, valuable in ecologic and economic terms.  相似文献   
172.

Background

Intrauterine infusions have been widely used for the treatment of endometritis in the mare. Nevertheless, their consequences on endocrine and endometrial molecular aspects are unknown. We studied the effect of a 1% povidone-iodine solution intrauterine infusion on progesterone levels, endometrial histology and estrogen (ERα) and progesterone (PR) receptor distribution by immunohistochemistry.

Methods

Fourteen healthy mares were used in this study. Estruses were synchronized and seven mares were treated with intrauterine infusions at days 0 and 2 post ovulation of two consecutive estrous cycles. Uterine biopsy samples were taken on days 6 and 15 post ovulation.

Results

The treatment did not induce an inflammatory response indicating endometritis, neither affected the ERα. However, it reduced the percentage of PR positive cells (PPC) on day 6 (deep glandular epithelium, control: 95.7 vs. infused: 61.5, P < 0.05). Treated mares tended to have lower progesterone levels on day 2 (3.9 ng/ml vs. 6.6 ng/ml, P = 0.07), and higher levels on day 15 compared with controls (4.4 ng/ml vs. 1.3 ng/ml, P = 0.07).

Conclusion

a 1% povidone-iodine infusion during days 0 and 2 post ovulation in healthy mares did not induce histological changes indicating endometritis, but altered progesterone concentrations and reduced the expression of endometrial PR at day 6 without affecting the ERα. These changes could reduce embryo survival.  相似文献   
173.
The effectiveness of flow cytometric assays for canine use is still requiring standardization. Despite several studies using purified mononuclear cells, no methodology or reference ranges are available for immunophenotyping of whole blood leukocytes (WBL). Fresh and pre-fixed WBL were used to identify cell-subsets, (Thy-1(+)/CD5(+)/CD4(+)/CD8(+)/CD21(+) and CD14(+)) and measure MHC-II, CD45RA/CD45RB expression. We described here an efficient method for fast quantification of canine-WBL, using pre-fix in a microplate assay, which allows long-term sample storage prior to phenotyping. Decreased percentage of CD5(+)-T-cells within the lymphocyte-gate and increased percentage of CD21(+)-B-cells were observed in young animals, which led to higher T/B cell ratios in middle-aged dogs. Lower numerical counts of Thy-1(+), CD4(+), CD8(+) and CD21(+) lymphocyte were observed when compared to young animals. In addition, we identified an age-related decline of MHC-II/CD45RA expression by lymphocytes. We proposed an improved method for phenotyping of canine peripheral blood mononuclear cells (PBMC) that has significant use for researchers and veterinary clinicians. The hematological changes of senescence previously identified on PBMC could be adequately reproduced on features identified by whole blood. Furthermore, this study supplies normal range references as baseline standards for clinical purposes, besides specific immunological parameters to monitor canine aging process.  相似文献   
174.
The gap between data analysis and site-specific recommendations has been identified as one of the key constraints on widespread adoption of precision agriculture technology. This disparity is in part due to the fact that analytical techniques available to understand crop GIS layers have lagged behind development of data gathering and storage technologies. Yield monitor, sensor and other spatially dense agronomic data is often autocorrelated, and this dependence among neighboring observations violates the assumptions of classical statistical analysis. Consequently, reliability of estimates may be compromised. Spatial regression analysis is one way to more fully exploit the information contained in spatially dense data. Spatial regression techniques can also adjust for bias and inefficiency caused by spatial autocorrelation. The objective of this paper is to compare four spatial regression methods that explicitly incorporate spatial correlation in the economic analysis of variable rate technology: (1) a regression approach adopted from the spatial econometric literature; (2) a polynomial trend regression approach; (3) a classical nearest neighbor analysis; and (4) a geostatistical approach. The data used in the analysis is from a variable rate nitrogen trial in the Córdoba Province, Argentina, 1999. The spatial regression approaches offered stronger statistical evidence of spatial heterogeneity of corn yield response to nitrogen than ordinary least squares. The spatial econometric analysis can be implemented on relatively small data sets that do not have enough observations for estimation of the semivariogram required by geostatistics. The nearest neighbor and polynomial trend analyses can be implemented with ordinary least squares routines that are available in GIS software. The main result of this study is that conclusions drawn from marginal analyses of this variable rate nitrogen trial were similar for each of the spatial regression models, although the assumptions about spatial process in each model are quite different.  相似文献   
175.
OBJECTIVE: To assess the efficacy and safety of 2 protocols using bromocriptine mesylate and prostaglandins to terminate unwanted pregnancy in bitches. DESIGN: Prospective randomized single-blind controlled study. ANIMALS: 34 crossbred and purebred bitches referred for possible pregnancy termination. Seven additional pregnant bitches were used as controls. PROCEDURE: Pregnancy was assessed by ultrasonographic examination from day 25 after mating in all bitches. Of the 34 bitches, 25 were pregnant and were randomly allocated to a treatment group. Group-1 dogs (n = 12) received a combination of increasing amounts of bromocriptine mesylate (15 to 30 microg/kg [6.8 to 13.6 microg/lb], p.o., q 12 h) and dinoprost tromethamine (0.1 to 0.2 mg/kg [0.045 to 0.09 mg/lb], s.c., q 24 h). Group-2 dogs (n =13) received a combination of increasing amounts of bromocriptine mesylate (the same schedule as group-1 dogs) and cloprostenol sodium (1 microg/kg [0.45 microg/lb], s.c., q 48 h). Both groups were treated until pregnancy termination. Results-Treatment success was 100% in both groups. Days of treatment required for pregnancy termination did not significantly differ between groups (5.0 +/- 0.6 vs 3.7 +/- 0.6 days, group-1 and group-2 dogs, respectively) although adverse effects only developed in group-1 dogs. At the end of the protocols, pseudopregnancy was observed in 3 of 12 and 6 of 13 group-1 and group-2 dogs, respectively. Pregnancy termination was followed by a mucoid sanguineous vulvar discharge for 3 to 10 days. CONCLUSIONS AND CLINICAL RELEVANCE: Results of this study indicate that protocols that combine the use of bromocriptine mesylate and prostaglandins for the termination of unwanted pregnancy in bitches are efficient and safe. The use of bromocriptine mesylate and cloprostenol had the best results and could be easily used on an outpatient basis.  相似文献   
176.
The presence of viruses in the weedLeonotis nepetaefolia in central México is reported from two field surveys.L. nepetaefolia, with viral-like symptoms such as mosaic, leaf deformation and calico, was observed growing next to cultivated fields in the Valley of Atlixco, Puebla, an important agricultural region in Mexico. The viruses harbored by this plant were characterized biologically, serologically and by molecular methods. The viruses detected wereAlfalfa mosaic virus (AMV),Cucumber mosaic virus (CMV), a satellite RNA of CMV (CMV satRNA) andTobacco mosaic virus (TMV). This last one was detected only during the first survey. CMV was the predominant virus found in both surveys, and was associated mostly to mosaic symptom. Phylogenetic analysis based on the coat protein gene sequence of CMV indicated that this isolate belongs to subgroup IA and confirmed that it is a mosaic-inducing isolate, whereas AMV belongs to subgroup II. Finally, CMV satRNA was found to be a non-necrogenic ameliorative variant, both by symptomatology and by phylogenetic analysis. Our results suggest thatL. nepetaefolia is a reservoir for several viruses in central Mexico, and given its wide distribution in several parts of the world, its role as a virus reservoir could be more general. http://www.phytoparasitica.org posting Aug. 31, 2005.  相似文献   
177.
Tropical Animal Health and Production - Equine chorionic gonadotrophin (eCG) is a hormone having FSH/LH effects. It can be used to enhance sperm quality in male goats (bucks) during the...  相似文献   
178.
The aim of the present study was to compare the endometrial gene expression of epidermal growth factor receptor (EGFR), nodal growth differentiation factor (NODAL), prostaglandin-endoperoxide synthase 2 (PTGS2), oestrogen receptor 1 (ESR1) and progesterone receptor (PGR) in repeat breeder cows (RBC) and non-RBC during diestrus. Endometrial samples were collected by cytobrush technique and stored in RNA stabilizing solution at −20°C until RT-qPCR analysis. Differences in endometrial mRNA expression of selected genes were assessed by ANOVA and simple (r) and the partial correlations (rp) among selected genes were performed. Results demonstrated that mRNA expression of EGFR and NODAL were higher in RBC than in non-RBC (3 and 25-fold change, p < .01 and p < .01, respectively), while the mRNA expression of PTGS2 was lower (1.56-fold change, p < .01). Although there were no differences detected in the mRNA expression of ESR1 and PGR, there was a positive correlation between the expression of ESR1 and EGFR (0.84, p < .05) and a negative correlation between PGR and PTGS2 (−0.49, p < .05). In conclusion, the difference on the endometrial mRNA expression of the genes included in the study between RBC and non-RBC indicates a deregulation of important mechanisms that are vital to establish a successful pregnancy. Thus, the present study provides useful insight as a base for future studies to elucidate the causes of RBC.  相似文献   
179.
The focus of this study was to investigate the chemical and colour changes occurring at different exposure times on artificially photo-irradiated surfaces of normal and red heartwood in beech in order to understand the mechanisms that cause the changes and to evaluate the possibility of usages of beech not only for energy production purposes. In this sense, surface colour modifications are of crucial importance to define the commercial value of beech wood. The artificial photo-irradiation of the wood samples was performed in a Solar Box, equipped with an ultraviolet filter that cuts off the spectrum at 280 nm. Reflectance spectrophotometry and Fourier transform infrared (FTIR) spectroscopy were used to assess artificial sunlight influence. The experimental data were statistically treated to evaluate their significance. Colour monitoring revealed that wood surface colour undergoes an important variation due to photo-irradiation, occurring within the first 24–48 h. Moreover, it was found that the chromatic coordinates (L*a*b*) in normal wood and in red heartwood tended to similar values after 504 h. FTIR spectroscopy allowed for investigating the rate of photodegradation of wood surface due to oxidation reactions of wood components. The results were validated by statistical analysis applied both to the colorimetric and spectroscopic data.  相似文献   
180.
Histidine kinases, used for environmental sensing by bacterial two-component systems, are involved in regulation of bacterial gene expression, chemotaxis, phototaxis, and virulence. Flavin-containing domains function as light-sensory modules in plant and algal phototropins and in fungal blue-light receptors. We have discovered that the prokaryotes Brucella melitensis, Brucella abortus, Erythrobacter litoralis, and Pseudomonas syringae contain light-activated histidine kinases that bind a flavin chromophore and undergo photochemistry indicative of cysteinyl-flavin adduct formation. Infection of macrophages by B. abortus was stimulated by light in the wild type but was limited in photochemically inactive and null mutants, indicating that the flavin-containing histidine kinase functions as a photoreceptor regulating B. abortus virulence.  相似文献   
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