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1.
Journal of Soils and Sediments - Bedload transport discharge is important in river engineering and morphodynamics. The Meyer-Peter and Müller (MPM) equation for determining bedload transport...  相似文献   
2.

In the North Nile Delta of Egypt, the impacts of overplanting paddy rice on water delivery performance have not been discussed quantitatively. Further, the amount of water that could have been saved if farmers would follow the planned area is unknown. In this study, water delivery performance was assessed by comparison of actual paddy rice planting and the government’s planned conditions. For both conditions, performance indicators relating to adequacy, equity, and dependability were analyzed across six locations in conjunction with the branch canal water level in 2013 and 2014. Based on the difference between the actual water supply and planned water demand, the amount of water that could have been saved for downstream uses was calculated. The average adequacy for the investigation period was good at one location, fair at 2 locations, and poor at 3 locations in both years. Further, adequacy under both actual and planned conditions was poor in late July at all locations. The planned adequacy and dependability downstream and equity among locations improved compared to the actual condition in both years. Under the condition that paddy rice area is the upper limit planned by the government, about 12.3% and 9.6% of water could be potentially saved in each year. The difference between actual and planned water delivery performance is caused by the branch canal’s low water level. Control of overplanting paddy rice and coordination of water distribution among water user associations would improve stable water level in the canal and, eventually, water delivery performance.

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3.
Abstract. Ammonia excretion rate of the marine bivalve Tapes decussatus (L.) varied with body weight, temperature and starvation. There was a steady state in the excretion rates, in which these rates neither increased nor decreased during the first 6 days of starvation. The highest rates of ammonia excreted during the steady state (before decline to lower level) depended on the temperature (715 ± 86 and 395 ± 55 μg NH4.N/clam/h × 10−2) at 28°C and 20°C, respectively. At 16°C, the steady state extended from 6h to 18d starvation. Ammonia excretion rates were higher for starved clams than for fed clams at all sizes, e.g. clams of 0·07 g dry flesh weight (28 ± 9 and 13 ± 5 μg NH4.N/clam/h × 10−2 respectively) at 16°C but not at 20°C and 28°C. At each temperature, weight-specific ammonia excretion rates were related to dry flesh weight of starved clams but were not related to fed ones.  相似文献   
4.
The in vivo and in vitro mechanistic anti-inflammatory actions of cucurbitacin E (CE) (Citrullus lanatus var. citroides) were examined. The results showed that LPS/INF-γ increased NO production in RAW264.7 macrophages, whereas L-NAME and CE curtailed it. CE did not reveal any cytotoxicity on RAW264.7 and WRL-68 cells. CE inhibited both COX enzymes with more selectivity toward COX-2. Intraperitoneal injection of CE significantly suppressed carrageenan-induced rat's paw edema. ORAC and FRAP assays showed that CE is not a potent ROS scavenger. It could be concluded that CE is potentially useful in treating inflammation through the inhibition of COX and RNS but not ROS.  相似文献   
5.
The effects of different concentrations of mercury on the cyanobacterium Phormidium fragile were studied. The results revealed that the dry biomass yield, protein content, chlorophyll a and carotenoids decreased with increased concentration of mercury from 0.01 to 1.5 mg L-. Also, malate dehydrogenase (MDH), glutamate dehydrogenase (GIDH) and nitrate reductase activity was suppressed by increased metal concentration whereas glutamic-oxalacetic transaminase (GOT) and glutamic-pyruvic transaminase (GPT) were hardly affected. Mercury uptake increased at the higher levels of the metal. On the other hand, all the amino acid components gradually increased with rise of the metal level except isoleucine, histidine and methionine which were suppressed by the smaller doses and completely disappeared by the larger doses of the metal.  相似文献   
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A new collection of several Red Sea sponges was investigated for the discovery of potential breast cancer migration inhibitors. Extracts of the Verongid sponges Pseudoceratina arabica and Suberea mollis were selected. Bioassay-directed fractionation of both sponges, using the wound-healing assay, resulted into the isolation of several new and known brominated alkaloids. Active fractions of the sponge Pseudoceratina arabica afforded five new alkaloids, ceratinines A–E (2–6), together with the known alkaloids moloka’iamine (1), hydroxymoloka’iamine (7) and moloka’iakitamide (8). The active fraction of the sponge Suberea mollis afforded the three known alkaloids subereamolline A (9), aerothionin (10) and homoaerothionin (11). Ceratinine B (3) possesses an unprecedented 5,7-dibrominated dihydroindole moiety with an epoxy ring on the side chain of a fully substituted aromatic moiety. Ceratinines D (5) and E (6) possess a terminal formamide moiety at the ethylamine side chain. Subereamolline A (9) potently inhibited the migration and invasion of the highly metastatic human breast cancer cells MDA-MB-231 at the nanomolar doses. Subereamolline A and related brominated alkaloids are novel scaffolds appropriate for further future use for the control of metastatic breast cancer.  相似文献   
8.
The present work aimed to describe the normal computed tomography (CT) and cross‐sectional anatomy of the nasal and paranasal sinuses in sheep and to correlate these features with the relevant clinical practices. Twenty apparent healthy heads of Egyptian native breed of sheep (Baladi sheep) of both sexes were used for studying these sinuses. CT images and their closely identical cross sections of the same head were selected and serially labelled in a progression from the rostral nasal region to the caudal aspect of the head using cheek teeth as landmarks. The current investigation reported seven sinuses in sheep, including maxillary, frontal, lacrimal and sphenoidal as paranasal, as well as dorsal and middle conchal and ethmoidal as nasal with unnoticeable palatine and ventral nasal conchal sinuses. The boundaries, extension, structure and communications of these sinuses were fully described. The current study provided anatomical guidelines for surgical interference in the frontal and maxillary sinuses during trephination, dehorning and sinuscopy. Also, an acceptable anatomical explanation was reported in this study for the high incidence of maxillary sinusitis than other sinuses. CT and cross‐sectional anatomy could be used as helpful database for diagnosis and clinical interference of the nasal and paranasal sinuses in sheep.  相似文献   
9.
Heterochromia iridis in water buffaloes (Bubalus bubalis)   总被引:1,自引:0,他引:1  
This study included 45 unaffected animals and 593 animals affected with heterochromia irides, and 85 enucleated eyeballs with heterochromia irides. The classification of heterochromia irides, morphology of normal and heterochromic irides, and the histology, ultrastructure, and scanning electron microscopy are presented. The incidence of heterochromia irides in water buffaloes was 7.62% affecting either one or both eyes. Both complete and partial heterochromia irides occurred. Complete heterochromia iridis is more frequent than the partial form in either bilateral or unilateral cases. The pupil has a dumb-bell-shape appearance. Granula iridica occurred at the upper (100%) and lower (30%) pupillary margins and originated from the posterior pigmented epithelium. In heterochromia irides, the melanocytes is absent in the anterior border and stromal layers, and iridal thickness appeared thinner than that of normal eyes.  相似文献   
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