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71.
Changes in the yields of the oleoresin and content of pungent bioactive principles: [6], [8], [10] gingerols and [6] shogaol of Jamaican ginger ( Zingiber officinale) were investigated during different stages of maturity (7-9 months). Ethanolic oleoresin extracts were prepared (95%, w/w) by cold maceration of dried ginger powder, and their percentage yields were calculated (w/w). The pungent bioactive principles in the ginger oleoresin were extracted with methanol and quantitatively analyzed by high performance liquid chromatography (HPLC). Ginger harvested at 8 months from Bourbon, Portland had the highest oleoresin yield (8.46 +/- 0.46%). [6] Gingerol was found to be the most abundant pungent bioactive principle in all the oleoresin samples investigated, with the 9 months sample from Bourbon, Portland containing the highest level (28.94 +/- 0.39%). The content of [6] gingerols was also found to be consistently high (7-9 months) in oleoresin samples from Johnson Mountain, St. Thomas (15.12 +/- 0.39 to 16.02 +/- 0.95%). The results suggest that Bourbon in Portland may be the most ideal location for cultivating ginger for high yields and quality, however, Johnson Mountain in St. Thomas could prove to be the least restrictive location, allowing for harvesting of good quality material throughout the maturity period (7-9 months).  相似文献   
72.
OBJECTIVE: To study associations between reported sugar intake and salivary bacteria (mutans streptococci, MS and lactobacilli, LB), and sugar intake in relation to body mass index (BMI), in women and adolescents. DESIGN: Cross-sectional study. Habitual dietary intake was reported in a questionnaire and whole saliva samples were collected and cultivated. SETTING: Stockholm, Sweden. SUBJECTS: Four hundred and fourteen mothers and their 16-year-old children (57% girls). RESULTS: Reported total sugar intake was significantly associated with LB in mothers (P = 0.001), but not in daughters and sons (P = 0.03 for mother-son interaction). When excluding lactose, the associations with LB and MS were significant in daughters (P = 0.032 and 0.005, respectively). High BMI and sugar intake from milk were independently associated with MS counts in mothers in a multiple regression model (R2 = 0.053). In daughters, sugar from beverages, candies/chocolates and fruits were all independently associated with MS counts (R2 = 0.074), whereas in sons, only mothers' MS counts were associated (R2 = 0.084). High BMI, low intake from cooked meals and high intake of candies/chocolates were all independently associated with LB in mothers (R2 = 0.076), while, except for candies/chocolates in daughters, no significant associations were found in children. BMI was significantly associated with bacteria counts in both mothers and children, whereas reported sugar intake was not. CONCLUSION: The associations between reported sugar intake and bacteria were generally weak. In mothers and daughters, some significant associations were found, but not in sons. Bacteria counts, but not reported sugar intake, were positively associated with BMI.  相似文献   
73.
Reef fishes are significant socially, nutritionally and economically, yet biologically they are vulnerable to both over‐exploitation and degradation of their habitat. Their importance in the tropics for living conditions, human health, food security and economic development is enormous, with millions of people and hundreds of thousands of communities directly dependent, and many more indirectly so. Reef fish fisheries are also critical safety valves in times of economic or social hardship or disturbance, and are more efficient, less wasteful and support far more livelihoods per tonne produced than industrial scale fisheries. Yet, relative to other fisheries globally, those associated with coral reefs are under‐managed, under‐funded, under‐monitored, and as a consequence, poorly understood or little regarded by national governments. Even among non‐governmental organizations, which are increasingly active in tropical marine issues, there is typically little focus on reef‐associated resources, the interest being more on biodiversity per se or protection of coral reef habitat. This essay explores the background and history to this situation, examines fishery trends over the last 30 years, and charts a possible way forward given the current realities of funding, capacity, development patterns and scientific understanding of coral reef ecosystems. The luxury live reef food‐fish trade is used throughout as a case study because it exemplifies many of the problems and challenges of attaining sustainable use of coral reef‐associated resources. The thesis developed is that sustaining reef fish fisheries and conserving biodiversity can be complementary, rather than contradictory, in terms of yield from reef systems. I identify changes in perspectives needed to move forward, suggest that we must be cautious of ‘fashionable’ solutions or apparent ‘quick fixes’, and argue that fundamental decisions must be made concerning the short and long‐term values of coral reef‐associated resources, particularly fish, for food and cash and regarding alternative sources of protein. Not to address the problems will inevitably lead to growing poverty, hardship and social unrest in many areas.  相似文献   
74.
Previous studies on the transport and absorption of resveratrol (3,5,4-O-trihydroxystilbene) were done using the pure compound. In this study, the absorption of resveratrol in digested peanut micellar from boiled and roasted peanuts was investigated using a human intestinal Caco-2 cell monolayer. The amount transported and rate of transport of both resveratrol glycosides and its hydrolytic product were quantified by a reverse-phase high-performance liquid chromatography method with mass spectrometric detection. Four peaks were identified in the digested peanut micellar of both boiled and roasted peanuts: two resveratrol glycosides, one resveratrol diglycoside, and possibly an acylated resveratrol glycoside. Resveratrol from roasted peanut micellar had a higher transport rate than those from the boiled peanut. This implies that resveratrol from roasted peanut is better absorbed than from boiled peanut. Also, the rate of transport and amount of resveratrol transported were higher for the hydrolytic product than the nonhydrolyzed glycosides. This has strong implications for in vivo absorption as the enzymatic activity of gut microflora could enhance the bioavailability of β-glycosides of dietary polyphenols.  相似文献   
75.
This study investigated the production of polyclonal (pAB) antibodies and the first time production of monoclonal (mAB) antibodies against the mycotoxin alternariol, and their implementation in enzyme immunoassay (EIA) for the rapid determination of alternariol in foods. Both EIAs were highly sensitive, with detection limits (IC??) of 35 ± 6.9 pg/mL (mAb EIA) and 59 ± 16 pg/mL (pAb EIA). Food products (n = 109; apple and tomato products, white wine) from German retail shops were analyzed. At a detection limit of 1-2 μg/kg, alternariol at 1-13 μg/kg was found with high frequency in apple (67%) and tomato (93%) products. Tomatoes with visible signs of Alternaria infection, stored at room temperature for up to 4 weeks, contained alternariol at levels up to 50 mg/kg, as determined by EIA and HPLC-FLD. It is concluded that the alternariol immunoassays present a versatile screening tool which could facilitate food control for Alternaria toxins.  相似文献   
76.
A market survey and review of government statistics were carried out to establish imports and exports of marine ornamental fishes into and out of Hong Kong, and to examine the local trade in terms of volume, value and species composition. Official government import figures for marine aquarium fishes were available from 1984 to 1991 and from 1997 and 1998. When compared with net imports, export and re-export volumes over the 15-year period were small, indicating that most imports entered the local market, or were exported unrecorded. The market survey of marine aquarium shops in Hong Kong was carried out between August 1996 and January 1997. From this survey, an annual estimate of 957,563 coral reef fish was calculated for the local trade, valued at HK$57,453,780, with a mean retail price of HK$60 per fish. These figures account for an estimated 2–3% of the global value and volume of marine aquarium fish trade, according to 1992 figures and, compared with government figures, indicate that official declarations of imports are underreported by at least 2–3 fold. A total of 342 marine aquarium fish species, from 49 families, were recorded with about 60% belonging to the families Labridae, Chaetodontidae, Pomacanthidae and Pomacentridae. It was estimated that a large proportion of the trade was in juvenile fishes and almost all fish were less than 10cm in standard length. It was common to see fishes in poor condition, species hard to maintain in captivity, or those listed for conservation concern, on sale. There are no regulations for local traders of live marine fishes other than those relating to either protected species or animal welfare. Licensing of traders in marine fishes could be introduced under existing Hong Kong legislation if fishes were to be re-classified as animals. This is strongly recommended as a step towards regulating and managing the trade in Hong Kong.  相似文献   
77.
Haemostatic alterations in dogs experimentally infected with Leishmania infantumwere studied before and after therapy with meglumine antimonate. Haemostatic function tests including platelet count, collagen-induced platelet aggregation, prothrombin time, activated partial thromboplastin time, thrombin time, plasma fibrinogen determination, and serum fibrinogen/fibrin degradation products concentration were performed. In the course of infection and before treatment, moderate thrombocytopenia (P<0·00001) decreased collagen induced platelet aggregation (P=0·0003), prolonged thrombin time (P=0·0117) and increased fibrinogen/fibrin degradation products were observed. Statistically significant differences of plasma fibrinogen concentration, prothrombin time, and activated partial thromboplastin time were not encountered. Haemostatic parameters returned to normal values after therapy. The results indicate that Leishmania infection may impair haemostasis suggesting induction of disseminated intravascular coagulation (DIC), and that treating dogs in an early stage of infection may potentially avoid the possibility of developing an uncompensated DIC.  相似文献   
78.
A carlavirus was isolated from leaves of a dandelion plant raised in the experimental garden of the Hugo de Vries Laboratory in Amsterdam. The virus was readily sap-transmissible and infected 24 out of the 52 plant species and cultivars tested, with visible symptoms in 18 of them.Myzus persicae andCuscuta subinclusa (dodder) did not transmit the virus. In addition the virus was not seed-transmitted in dandelion. Dilution end-point was 10–5, thermal inactivation occurred at between 80–85°C and longevity in vitro was approximately 24h. The virus had a sedimentation coefficient of 136 S. Polyacrylamide gel electrophoresis of the coat protein gave two bands, consisting of proteins with molecular masses ranging from 37 000 to 34 300 Da (band I) and from 34 000 to 32 800 Da (band II). The molecular mass of the RNA was 2.84 x 106 Da. The average buoyant density of the virus was 1.306 gcm–3 and the average A260/A280 ratio 1.16. The virus particles had a normal length of 668 nm. with the light microscope, large mainly vacuolate inclusions were observed in the epidermal cells of infectedNicotiana cleavelandii leaves. In ultra-thin sections of systemically infected leaves ofN. clevelandii, bundles of aggregated virus particles were detected, whereas in infected dandelion leaves there were fewer aggregates and more scattered virus particles. There was a close serological relationship to dandelion latent virus, chrysanthemum virus B and potato virus S and a more distant one to carnation latent virus, elderberry carlavirus,Helenium virus S and potato virus M. The occurrence of the virus was found to be restricted to dandelion plants in the experimental garden in Amsterdam. On the basis of large differences in host range, symptomatology and lack of transmission byM. persicae it was decided that the virus could not be considered a strain of either dandelion latent virus, chrysanthemum virus B or potato virus S. We therefore propose that it be called dandelion carlavirus.Samenvatting Een carlavirus werd geïsoleerd uit een paardebloemplant, die opgekweekt was in de proeftuin van het Hugo de Vries-Laboratorium in Amsterdam. Het virus kon gemakkelijk met sap worden overgebracht en was in staat 24 van de 52 getoetste plantesoorten en-cultivars te infecteren, waarbij op 18 van deze symptomen zichtbaar werden.Myzus persicae en warkruid (Cuscuta subinclusa) konden het virus niet overbrengen. Evenmin kon het virus met zaad van geïnfecteerde planten van paardebloem overgaan. De verdunningsgrens was 10–5, de inactiveringstemperatuur 80–80°C en de houdbaarheid in vitro ongeveer 24 uur. Het virus had een sedimentatiecoëfficiënt van 136 S. Polyacrylamide-gelelektroforese van het manteleiwit resulteerde in twee banden, bestaande uit eiwitten met molecuulmassa's die varieerden van 37000 tot 34 3000 Da (band I) en van 34 000 tot 32 800 Da (band II). De molecuulmassa van het RNA was 2,84×106Da. De gemiddelde zweefdichtheid van het virus bedroeg 1,306g cm–3 en de gemiddelde A260/A280 verhouding was 1,16. Het virus had een normale lengte van 668 nm. In de epidermiscellen van geïnfecteerde bladeren vanNicotiana clevelandii werden met de lichtmicroscoop insluitsels met draderige en vacuoleachtige structuren waargenomen. In ultradunne coupes van systemisch geïnfecteerde bladeren vanN. clevelandii waren bundels geaggregeerde virusdeeltjes zichtbaar. In geïnfecteerde bladeren van paardebloem werden daarentegen meer verspreid voorkomende virusdeeltjes gevonden en minder aggregaten. Het virus vertoonde een sterke serologische verwantschap met het dandelion latent virus, chrysantevirus B en aardappelvirus S; er was een geringe verwantschap met het latente anjervirus, het carlavirus van vlier, Helenium virus S en het aardappelvirus M. Het vóórkomen van het virus bleek beperkt te zijn tot paardebloemen in de proeftuin in Amsterdam. Gezien de grote verschillen in waardplantenreeks, symptomatologie en overdracht metM. persicae hebben we gemeend, dat het virus niet slechts als een stam kon worden beschouwd van hetzij het dandelion latent virus, hetzij het chrysantevirus B en het aardappelvirus S. We stellen voor de naam carlavirus van paardebloem aan dit virus te geven.  相似文献   
79.
The aim of this study was to identify ultrasound accessible blood vessels in the loggerhead sea turtle (Caretta caretta) and describe their Doppler waveform patterns, peak systolic velocity, mean velocity, systolic/diastolic ratio as well as pulsatility and resistive indices. B-mode, colour and pulsed-wave Doppler examinations were performed on 10 turtles. Flow measurements were recorded for the left and right aorta, epigastric and internal iliac arteries, and right hepatic vein. Additionally, the large blood vessels of three dead turtles were injected with latex and dissected for anatomical support. A parabolic flow velocity profile was observed in all arteries. The waveforms of the right and left aortic arteries showed an unusual pattern when compared with mammals. The hepatic vein flow velocity waveform of the loggerhead sea turtle was found to be similar to that in the dog, although the flow velocity in the C-wave was higher than that in the A-wave. The low resistance flow pattern observed suggests that the loggerhead sea turtle's organs require a continuous blood supply.  相似文献   
80.

Background  

The Brazilian Atlantic Forest is highly endangered and only about 7% of the original forest remains, most of which consists of fragments of secondary forest. Small mammals in the Atlantic Forest have differential responses to this process of fragmentation and conversion of forest into anthropogenic habitats, and have varying abilities to occupy the surrounding altered habitats. We investigated the influence of vegetation structure on the micro-scale distribution of five small mammal species in six secondary forest remnants in a landscape of fragmented Atlantic Forest. We tested whether the occurrence of small mammal species is influenced by vegetation structure, aiming to ascertain whether species with different degrees of vulnerability to forest fragmentation (not vulnerable: A. montensis, O. nigripes and G. microtarsus; vulnerable: M. incanus and D. sublineatus; classification of vulnerability was based on the results of previous studies) are associated with distinct vegetation characteristics.  相似文献   
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