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141.
Root-pruning is generally recommended as an appropriate treatment to reduce competition for soil water and/or nutrients and suppression of crop yield in areas adjacent to windbreaks. Several recent studies suggest, however, that factors other than soil water might be causing yield reduction at the interface. For two consecutive years, we evaluated root-pruning effects on soil water at the windbreak/crop interface under both cropped (soybean [Glycine max (L) Merr.] variety Iroquois, 1997) and non-cropped (1998) conditions in Mead, Nebraska, USA. Volumetric soil water content near the windbreaks was systematically measured at various soil depths, distances from the windbreak, and windbreak exposures using Time Domain Reflectometry (TDR). Overall differences in soil water content between root-pruned and non-pruned plots in soybean were smaller in magnitude at all distances in both the west (windbreak on the east side) and the east (windbreak on the west side) exposures in 1997, compared with the non-cropped condition in the south exposure in 1998. With a soybean crop in 1997, volumetric soil water content in the east exposure averaged 2.3% greater in the top 30 cm of the soil profile at a distance of 0.75H (H = windbreak height) into the field from the windbreak when compared to the non-pruned treatment. In the west exposure, however, the differences were undetectable at corresponding distance and depth. The increase in soybean yield in root-pruned plots corresponded well with the observed differences in soil water content at various distances, especially in the east exposure. Under a non-cropped condition in 1998, soil water content in the root-pruned plots was significantly greater than the non-pruned plots in the top 45-cm profile, averaging 3.3% at 0.75H and 2.2% at 1.0H. Beyond 1.0H, the increase was not significant. These results agree with the previously reported range of crop yield suppression near windbreaks, indicating that soil water competition between the crop and windbreak is highly related to, and probably plays a leading role in yield suppression within the competition zone.This revised version was published online in November 2005 with corrections to the Cover Date.  相似文献   
142.
Polycyclic aromatic hydrocarbons (PAHs) were determined by an HPLC method with fluorescence detection in bivalves (Mitylus galloprovincialis), cephalopods (Todarodes sagittatus), crustaceans (Aristeus antennatus), and fish (Mullus surmeletus, Scomber scombrus, Micromesistius poutassou, and Merluccius merluccius) caught in the Gulf of Naples (Tyrrhenian Sea, Italy). Anthracene, fluoranthene, pyrene, benz(a)anthracene, chrysene, benzo(b)fluoranthene, and benzo(k)fluoranthene were detected, at different concentrations, in all of the examined marine organisms, whereas benzo(a)pyrene, dibenz(a,h)anthracene, benzo(g,h,i)perylene, and indeno(1,2,3-cd)pyrene were found only in Mediterranean mussels. Of mussels collected in winter 71.43% exceeded the maximum residual levels (MRL) fixed for the benzo(a)pyrene in European Regulation 208/2005/EC, whereas all samples collected in summer reported values lower than this limit. In comparison to the other marine organisms, the mussels showed the highest PAH concentrations (p < 0.01). Fish showed total PAH levels lower than those of cephalopods and, in particular, European hake showed the lowest values (6.06 ng/g of fresh weight).  相似文献   
143.
Accurate diagnosis of canine filariosis is essential for choosing correct therapeutic approach. Therefore, reliable methods for discriminating among the different filarial infections in dogs are needed. The authors report simple and highly specific molecular methods that identify the three most common filarial nematodes of European dogs: Dirofilaria immitis, D. repens and Acanthocheilonema (syn. Dipetalonema) reconditum, based on (1) PCR amplifications of mitochondrial DNA (12S rDNA and coxI) with general filarial primers followed by digestion with restriction enzymes that generates band polymorphisms clearly discriminating the three species and (2) PCR amplifications with species-specific primers to support the restriction analysis, in particular in the case of multiple infections.  相似文献   
144.
The purpose of this study was to investigate the prognostic value of various clinical, ECG, echocardiographic, and Doppler echocardiographic variables in dogs with dilated cardiomyopathy. The relationship to survival of 11 variables was evaluated in 63 dogs. Studied variables were age at time of diagnosis, class of heart failure (HF), dyspnea, ascites, atrial fibrillation (AF), ejection fraction (EF), E-point septal separation, end-diastolic volume index, end-systolic volume index (ESV-I), and restrictive or nonrestrictive transmitral flow (TMF) pattern. Median survival time was 671 days (lower 95% confidence limit, 350 days). Survival curves showed that severity of HF, ascites, ESV-I greater than 140 mL/m2, EF less than 25%, and restrictive TMF pattern had a significant negative relation to survival time. Thirty-nine dogs with both sinus rhythm and AF presented adequate TMF recordings; in these dogs, after stratification by TMF pattern, the restrictive TMF pattern was the most important negative prognostic indicator. We conclude that in dogs with dilated cardiomyopathy the restrictive TMF pattern appears to represent a useful prognostic indicator. Class of HF, ascites, ESV-I, and EF are also useful indexes if an adequate TMF pattern is not recorded.  相似文献   
145.
146.
Polyphenolic grapevine components involved in plant resistance against pathogens possess various pharmacological properties that include nitric oxide (NO)-dependent vasodilation and anti-inflammatory and free radical scavenging activities, which may explain the protective effect of moderate red wine consumption against cardiovascular disease. The aim of this work was (a) to verify the possibility that preharvest treatments of grapevine with a plant activator, benzo-(1,2,3)-thiadiazole-7-carbothioic acid S-methyl ester (BTH), could lead to an enriched nutraceutical potential of wine and (b) to characterize the profile of metabolites responsible for pharmacological activity. Plant spraying at the end of veraison, with a water suspension of BTH (0.3 mM), led to increased whole anthocyanin content as confirmed by HPLC comparative analysis. Extracts from berry skins of BTH-treated grapevines caused NO-dependent vasorelaxation, with a concentration-response curve that was significantly shifted to the left of the control non-BTH-treated curve. Moreover, 1:1000 dilutions of berry extracts from BTH-treated plants significantly increased basal production of guanosine 3',5'-cyclic monophosphate (cGMP) in human vascular endothelial cells when compared to the corresponding extracts of untreated plants. These results show that BTH treatment increases anthocyanin content of grape extracts, as well as their ability to induce NO-mediated vasoprotection. No increase of anthocyanin content was observed in the wine extracts from BTH-treated vines. It is concluded that BTH treatment could be exploited to increase the nutraceutical potential of grapes.  相似文献   
147.
148.
To date, limited information is available on the ability of 'Hobi'-like pestiviruses (putative bovine viral diarrhoea 3) to infect and cause disease in animal species traditionally affected by pestiviruses. In order to obtain new insights into host range and pathogenic potential of this atypical pestivirus, BVDV-seronegative calves (n=5), lambs (n=5) and piglets (n=5) were experimentally infected with the European 'Hobi'-like strain Italy-1/10-1, whereas two animals per species served as uninfected controls. Appearance of clinical signs, leukopenia, viremia, viral shedding and seroconversion were monitored for 28 days post-infection. Calves and lambs were successfully infected, displaying respiratory signs (nasal discharge), moderate hyperthermia and leukopenia, viremia and viral shedding through the nasal and faecal routes. Antibody responses were observed in both animal species by ELISA and virus neutralisation assays. In contrast, inoculated piglets did not display any clinical signs nor leukopenia and viral RNA was not detected in any biological samples. Nevertheless, the presence of detectable antibodies by virus neutralisation accounted for a successful, albeit limited infection of these animals.  相似文献   
149.
An 8-year-old intact male dwarf rabbit (Oryctolagus cuniculus) was presented with a 2-month history of unilateral scrotal swelling. The external physical examination of the rabbit patient confirmed the severe, unilateral, fluid-filled scrotal distention. Radiographic images of the effected scrotum revealed a soft tissue swelling in the area of the left testicle, and the absence of the urinary bladder in the caudal abdomen. Ultrasonography verified the presence of a fluid-filled mass in the scrotum, enveloping the left testicle. A fine-needle aspiration of the scrotal mass yielded urine, thus a diagnosis of a nonreducible herniation of the urinary bladder into the scrotum was made. An inguinal herniorrhaphy was performed, and the bladder was successfully reduced into the abdominal cavity. A bilateral routine castration and left scrotal ablation were also performed. Two months after surgery no recurrence was noted, and the patient had normal urinary function. Inguino-scrotal bladder herniation is rare in both humans and animals. Male rabbits are predisposed to inguinal and scrotal hernias because their inguinal rings remain open throughout life. Herniation of the urinary bladder should be considered as a differential diagnosis when intact male rabbits are presented with unilateral scrotal swelling.  相似文献   
150.
The aim of the present study was to analyze the effects of drug detection training on behavior and blood neurotransmitter levels in drug detection dogs so as to investigate some variables influencing dog reactivity and responsiveness to training. In all, 20 dogs were sampled out of the Guardia di Finanza canine population. All the subjects were born, reared, housed, and trained in the same facility and followed the same training sessions. Dogs’ behavioral reactivity was scored according to a standardized working dogs test to evaluate natural dog attitudes. Plasma samples were analyzed by the high-performance liquid chromatography method to evaluate adrenaline, noradrenaline, L-3,4-dihydroxyphenylalanine, homovanillic acid (HVA), 3-methoxy-4-hydroxyphenylglycol acid (MHPG), 5-hydroxyindole acetic acid (5-HIAA), and 5-hydroxytryptamine (5-HT) levels. 5-HT and 5-HIAA were also analyzed from platelets. The analysis was carried out considering training, breed, and sex as independent variables. From a behavioral point of view, significant differences were recorded before and after training in “sociability,” “playfulness,” “predatory instinct,” and “aggressiveness” scores. Lower levels of platelet 5-HT and 5-HIAA were found after training. Plasma L-3,4-dihydroxyphenylalanine levels differed between sexes, with males showing higher concentrations. These results underline the importance of complete and objective evaluations protocols of the dogs before, during, and after drugs search training to determine effective and successful selection strategies and training procedures.  相似文献   
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