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1.
Different developmental stages of Microplitis rufiventris Kok. larvae were each exposed to a sublethal dosage (0.4?ppm) of Lefenuron [N-{2,5-dichloro-4-(1,1,2,3,3,3-hexafluoropropoxy)-phenylaminocarbonyl}-2, 6-difluorobenzamide] or Lefenuron/Deltanet [O-n-butylO-(2.2-dimethyl-2, 3-dihydrobenzofuran-7-y1)-N, N'-dimethyl-N-N'-thiodicarbamate] by feeding treated artificial diets to parasitized Spodoptera littoralis (Boisd.) larvae to evaluate their effects on the reproductive potential of resulting parasitoids. Lefenuron treatments caused a great reduction in the reproductive ability of either the host insect or its parasitoid. Ovaries of parasitoid females (1 day old) emerged from Lefenuron/Deltanet treatments contained more ova than those from either Lefenuron or controls. Experienced females from Lefenuron/Deltanet treatments deposited significantly more eggs and contained at death more remaining mature oocytes in their calyx and egg-reservoirs. The combination of carbamate insecticide (Deltanet) and chitin-inhibiting growth regulator (Lefenuron) may enhance the reproductive ability of insect parasitoid and may provide a potential means for developing more effective biological control methods against insect pests.  相似文献   
2.
Two field experiments were carried out during 1982/83 and 1983/84 seasons at Experimental Farm of National Research Centre at Shalakan, Kalubia Governorate, Egypt, to study the effects of supplemental growth factors on the reversal of glyphosate-induced inhibition in photosynthetic pigments and protein in faba beans. A split plot design with four replications was used in both seasons. Glyphosate at 0,312 and 468 g.a.i./ha as well as the untreated treatment, arranged at random in main plots while, the growth factors, i.e., growth regulators, amino acids and nutrient elements at different concentrations distributed randomly in the sub plots. The results could be summarized as follows:
1. Glyphosate decreased chlorophyll a, b and carotenoides content and the total pigments content in the leaves of faba bean plants, as well as, the protein content of seeds and protein yield per hectare.
2. The treatments of phenylalanine at 500 ppm, urea at 1 %, cytolinin at 4/1000 and tryptophan at 500 ppm, reversed the glyphosate-induced-phytotoxicity on decreasing the chlorophyll a, b content and total pigments content in faba bean leaves. The same treatments, as well as, zinc sulfate at 1 %, reversed the glyphosate-induced-phytotoxicity on decreasing the carotenoids content in faba bean leaves.
3. The treatment of G a 3 at 100 ppm gave the highest percentage of crude protein in seeds, while the lowest value was obtained from cytokinin at 4/1000, in both seasons.
4. The treatments of cytokinin at 4/1000, phenylalanine at 500 ppm and tryptophan at both levels, reversed the glyphosate-induced-phytotoxicity on decreasing the protein yield per h.  相似文献   
3.
Zusammenfassung Traditionelle, extensiv bearbeitete Olivenhaine, aber auch moderne Intensiv-Plantagen mit künstlicher Bewässerung und hohem Einsatz von Düngern bzw. chemischen Pflanzenschutzmitteln kennzeichnen die derzeitigen verschiedenen Anbauformen der Olive im Mittelmeerraum. Schadlepidopteren wie die Olivenmotte (Prays oleae, Lep.: Yponomeutidae) und die Jasminmotte (Palpita unionalis, Lep.: Pyralidae) werden durch regelmässigen Insektizideinsatz bekämpft. Das von der EU geförderte internationale Forschungsprojekt TRIPHELIO zielte auf die Entwicklung insektizidfreier Alternativmethoden durch (1) die Optimierung der pheromongestützten Überwachung und Verwirrtechnik, (2) der Anwendung von Habitatmanagement-Strategien zur Förderung natürlicher Gegenspieler, und (3) dem Einsatz von Trichogramma-Schlupfwespen. Zusätzlich wurden Module für eine optimale Anwendung biotechnischer und biologischer Methoden bezüglich der Phänologie der Schadinsekten und möglicher Nebenwirkungen von Pestiziden erarbeitet. Die intensive Kooperation zwischen Wissenschaftlern und Praktikern aus mehreren Ländern Europas und Nordafrikas erlaubte den Entwurf möglicher Lösungsansätze für verschiedene Anbaubedingungen und klimatische Regionen des Mittelmeerraumes. Die wichtigsten Ergebnisse und Ausblicke für eine zukünftige praktische Umsetzung werden in dieser Veröffentlichung beschrieben.  相似文献   
4.
5.

Background:

Hypertension is one the most common causes of chronic kidney disease (CKD). One of the major concerns in hypertensive patients is early detection of renal disorders. In the past, serum creatinine (Scr) concentration was used as a marker of kidney function, but it proffers a late reflection of reduced glomerular filtration rate. Cystatin C and neutrophil gelatinase-associated lipocalin (NGAL) have been recently proven to be useful for quantification of CKD. Therefore, we compared the diagnostic value of NGAL with cystatin C and creatinine to evaluate kidney function in hypertensive patients.

Methods:

In this study, 42 hypertensive patients and 30 healthy volunteers were recruited. Serum cystatin C (Scys C) and plasma NGAL were measured using ELISA method. Creatinine, urea, hemoglobin, fibrinogen, and C-reactive protein were measured according to the routine methods. Estimated glomerular filtration rate (eGFR) was considered as the gold standard method (cut-off value of < 78 ml/min/1.73 m2.

Results:

In the patient group, plasma NGAL, cystatin C, and creatinine were all significantly correlated with eGFR, and plasma NGAL correlated best with eGFR. Receiver-operating characteristics analysis indicated that plasma NGAL was a better indicator than creatinine and cystatin C for predicting a GFR < 78 ml/min/1.73 m2. The sensitivity and specificity for NGAL were 96% and 100%, for cystatin C were 92% and 60% and for creatinine were 76% and 47%, respectively.

Conclusion:

Plasma NGAL demonstrated a higher diagnostic value to detect kidney impairment in the early stages of CKD as compared to Scys C and Scr in hypertensive patients.Key Words: Neutrophil gelatinase-associated lipocalin (NGAL), Cystatin C, Creatinine, Hypertension  相似文献   
6.
The objective of this study is to investigate the effect of different time and rates of boron (B) foliar application on olive (Olea europaea L.) tree's tissue boron concentration, total phenol, chlorophyll, total soluble sugars, and endogenous hormones. A field experiment was conducted during two successive seasons 2010/2011 and 2011/2012 using 20 years old olive trees cv. Frantoio. The trees are grown in sandy soil planted at 5 × 5 m apart under drip irrigation system at the Nuclear Research Center Experimental Farm, Inshas, El-Qaliubiya Governorate, Egypt. Boron was applied foliarly as boric acid at the following rates (0.0, 100, 200, 300, 400, 500 mg L?1) at flower initiation and after 1 and 2 months from flower initiation. Results showed that boron was significantly effective in increasing leaf, bud, and fruit boron concentration. Total phenol concentration in leaves and buds were significantly highest in the control treatment, significantly decreased as the boron application rate increased. Total chlorophyll, chlorophyll a and b, and total soluble sugars significantly increased as the boron application rate increased and the highest increase was achieved at 200 mg L?1 boron concentration rate. Leaf and bud endogenous indole acetic acid (IAA) and abscisic acid (ABA) were highest in the control treatment; they decreased as the boron application rate increased. However, gibberellic acid (GA3) increased in response to boron treatments compared with the control. The maximum increase was observed at 200 mg L?1 boron rate. We concluded that boron is mobile in olive tree as reproductive organs accumulated more boron than vegetative organs. There is evidence that boron is involved in reduction of phenols, increase in fruit set, and in sugar transport. A balance in endogenous hormones (IAA, GA, ABA) concentrations in olive tree has induced the maximum fruit set and yield.  相似文献   
7.
8.
Background:CE is a zoonotic parasitic infection caused by Echinococcus granulosus worldwide and is associated with economic losses among livestock animals. EG95 is an immunogenic antigen from the E. granulosus. Lactococcus lactis has been prested as a safe vehicle for antigen delivery. The goal of this study was to design a novel L. lactis strain displaying EG95 as a vaccine delivery system. Methods:The eg95 encoding gene fragment fused to the M6 anchoring protein was cloned into the pNZ7021 vector, and L. lactis NZ9000 displaying recombinant EG95 was constructed. The expression of an approximately 32-kDa EG95 protein was confirmed by Western blotting and immunofluorescence analysis. The immune responses were evaluated in BALB/c mice immunized orally and subcutaneously with the live and killed recombinant L. lactis, respectively. Results:Total IgG level in mice immunized with heat-killed recombinant L. lactis (pNZ7021-eg95) significantly increased compared to the control group. sIgA was significantly higher in mice received live recombinant L. lactis (pNZ7021-eg95) compared to the control mice. Splenic lymphocytes from immunized mice represented the high levels of IFN-γ and the low-levels of IL-4 and IL-10. Conclusion:Our results indicate that immunization with EG95-expressing L. lactis can induce both specific humoral and cellular immune responses in mice. Key Words: Echinococcus granulosus, Lactococcus lactis, Immunization, Vaccines  相似文献   
9.
This study estimates the levels and determinants of farm‐level technical efficiency of shrimp farmers, using the stochastic production frontier function involving a model for technical inefficiency effects. A sample of 90 brackish water shrimp farms were surveyed in the region of Shyamnagar Upazila of the Satkhira District, Bangladesh, to study their economic efficiencies. Data were collected, using a questionnaire survey from September to October 2011. The mean technical efficiency level of the shrimp farmers was estimated at 82%, and thus, farmers operate 18% below the production frontier. The results suggest that the inefficiency effect is significant, and that education, age, non‐farm income and distance of the farm are significant determinants of technical inefficiency. By operating at full technical efficiency levels, shrimp production can increase from the current yield of 225.56 to 265.28 kg/ha. Besides improving technical efficiency, technological progress and extension services (such as dissemination of proper information of the technological practices and further adoption of technological practices) can also contribute to increased shrimp production levels. Finally, quality feed and fingerling at affordable prices need to be ensured to further promote shrimp production.  相似文献   
10.
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