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131.
The aim of this study was to evaluate the distribution of frozen–thawed spermatozoa within the uterine lumen and oviducts following intrauterine laparoscopic deposition at two sites. Twelve bitches of unknown reproductive history were randomly distributed into two groups. Semen (3 ml containing 300 × 106 frozen–thawed spermatozoa) was infused at the uterine body (UB group) or at the cranial tip of the left uterine horn. A 22‐G catheter was used to access the uterine lumen. Sperm cell distribution was evaluated after ovariohysterectomy performed 3 h after artificial insemination (AI). There was no difference between groups in mean time to perform AI. Spermatozoa were detected in all uterine segments, including the tip of both horns, but none was detected in the oviduct. The 22‐G catheter facilitated deposition of semen in the uterine lumen, particularly at the UB site. Sperm cell distribution occurred evenly along both horns, independent of the site of semen deposition.  相似文献   
132.
Rational molecular design and processing, enabling large-area molecular ordering, are important for creating high-performance organic materials and devices. We show that, upon one-step hot-pressing with uniaxially stretched Teflon sheets, a polymer brush carrying azobenzene-containing mesogenic side chains self-assembles into a freestanding film, where the polymer backbone aligns homeotropically to the film plane and the side chains align horizontally. Such an ordered structure forms through translation of a one-dimensional molecular order of the Teflon sheet and propagates from the interface macroscopically on both sides of the film. The resultant wide-area bimorph configuration allows the polymer film to bend rapidly and reversibly when the azobenzene units are photoisomerized. The combination of polymer brushes with hot-pressing and Teflon sheets provides many possibilities in designing functional soft materials.  相似文献   
133.
Chlamydophila felis is a causative agent of acute and chronic conjunctivitis and pneumonia in cats. Cats can be vaccinated with killed or attenuated C. felis. However, current serodiagnostics cannot distinguish these cats from naturally infected cats. This causes difficulty of early diagnosis and seroepidemiological survey for C. felis. We previously reported that C. felis CF0218 can be used as a C. felis-infection-specific diagnostic antigen in experimentally infected and/or vaccinated cats. In this study, we evaluated an enzyme-linked immunosorbent assay using recombinant CF0218 as antigen (CF0218-ELISA) to detect anti-C. felis antibody in 714 sera of domestic cats whose histories of vaccination against C. felis are known. The 44 vaccinated cats were 93% negative using CF0218-ELISA; half of these scored positive by immunofluorescence assay (IFA) using C. felis-infected cells as antigen. The 670 non-vaccinated cats had CF0218-ELISA positivity rates that were statistically in agreement with IFA (18% vs. 21%). These results show that CF0218, which was identified as a C. felis-infection-specific antigen, is a useful serodiagnostic antigen to distinguish naturally C. felis-infected cats from vaccinated and non-infected cats.  相似文献   
134.
The skin fluke Neobenedenia girellae has become a serious problem in Japan since the 1990s. Present control methods focus on the removal of the attached parasite and these post-infection treatments are often labor intensive, time consuming, and/or stressful to fish. Chub mackerel Scomber japonicus are highly susceptible to N. girellae. However, because of their sensitive nature, bath treatments may cause mortality. In this study, we investigated the efficacy of cage shading to reduce skin fluke infection and the frequency of conventional post-infection treatments. Juvenile mackerel were reared in cages with or without shade for 3 months and their skin fluke infections were monitored. We performed either freshwater baths or oral administration of praziquantel if fluke intensity exceeded the given criteria. In unshaded cages, 3 total bath treatments or 6 total drug treatments were conducted. In contrast, no treatment was required for the shaded cage. The overall fluke intensity in the shaded cage was less than half that of the unshaded cages, despite the lack of treatments. This study demonstrated for the first time the practical use of shading in fish farms to reduce skin fluke infection.  相似文献   
135.
Agricultural fields, including rice (Oryza sativa L.) paddy fields, constitute one of the major sources of atmospheric methane (CH4) and nitrous oxide (N2O). Organic matter application, such as straw and organic fertilizer, enhances CH4 emission from paddy fields. In addition, rice straw management after harvest regulates CH4 emissions in the growing season. The interaction of tillage times and organic fertilizer application on CH4 and N2O emissions is largely unknown. Therefore, we studied the effects of fallow-season tillage times and fertilizer types on CH4 and N2O emissions in paddy fields in Ehime, southwestern Japan. From November 2011 to October 2013, four treatments, two (autumn and spring) or one (spring) in the first year, or two (autumn and spring) or three (autumn, winter, and spring) in the second year times of tillage with chemical or organic fertilizer application, were established. Gas fluxes were measured by the closed-chamber method. Increasing the number of tillage times from one to two decreased succeeding CH4 emission and the emission factor for CH4 (EFCH4) in the rice-growing season, suggesting that the substrate for CH4 production was reduced by autumn and spring tillage in the fallow season. Higher EFCH4 [1.8–2.0 kg carbon (C) ha?1 d?1] was observed when more straw was applied (6.9–7.2 Mg ha?1) in the second year. Organic fertilizer application induced higher CH4 emission just after the application as basal and supplemental fertilizers, especially at a lower straw application rate. This indicated that EFCH4 in the organically managed fields should be determined individually. Organic fertilizer application with two tillage times induced N2O efflux during the rice-growing season in the second year, but N2O emissions were not affected by winter tillage. Although paddy fields can act as an N2O sink because of reduced soil conditions when straw application was high, application of organic C and nitrogen as fertilizer can enhance N2O production by the denitrification process during the growing season, especially in the ripening stage when soil anaerobic conditions became moderate. These results suggest that negative emission factors for N2O (EFN2O) can be applied, and EFN2O of organic fertilizer should be considered during the estimation of N2O emission in the paddy field.  相似文献   
136.
Little information is available on the relationship between computed tomography (CT) imaging findings and the pathologic diagnosis of canine hepatic tumors. Our purpose was to clarify the characteristic features of CT findings in liver tumors in dogs. Data from 33 dogs with either a hepatocellular carcinoma, n = 14, hepatocellular adenoma, n = 14, or nodular hyperplasia, n = 5 were summarized from medical records. CT features for each histologic diagnosis were characterized and analyzed statistically. Common findings in hepatocellular carcinoma included central (79%, P = 0.0030) and marginal enhancement (93%, P = 0.00043) in the arterial phase, cyst-like lesions (93%), capsule formation (93%), and hypoattenuation in the portal (86%), and equilibrium phases (93%). Hepatic adenoma was characterized by a characteristic diffuse enhancement pattern during the arterial phase (57%, P = 0.013), which was also found in nodular hyperplasia (60%), but never in hepatocellular carcinoma. Nodular hyperplasia was less likely to have a capsule structure (20%, P = 0.0087). Mass size was significantly smaller in nodular hyperplasia than in hepatocellular carcinoma and hepatic adenoma (P = 0.0033 and 0.038, respectively). Hyperattenuation in the arterial and the portal phase i.e. contrast retention, was more frequent in hepatic adenoma than in the other groups (P = 0.037 and 0.037, respectively). Nodular hyperplasia was more frequently isoattenuating in the equilibrium phase (P = 0.043).  相似文献   
137.
The effect of appetite regulatory hormone cholecystokinin (CCK) on the secretions of oxyntomodulin (OXM) and ghrelin, and the effect of ghrelin on the secretions of CCK and OXM were studied in ruminants. Eight Holstein steers, 7 months old, 243 ± 7 kg body weight (BW), were arranged in an incomplete Latin square design (8 animals × 4 treatments × 4 days of sampling). Steers were intravenously injected with 10 µg of sulfated CCK‐8/kg BW, 20 µg of acyl ghrelin/kg BW, 100 µg of des‐acyl ghrelin/kg BW or vehicle. Blood samples were collected from ?60 min to 120 min relative to time of injection. Plasma concentrations of ghrelin, sulfated CCK and OXM were measured by double‐antibody radioimmunoassay. Plasma acyl ghrelin was increased to peak level (428.3 ± 6 pg/mL) at 60 min after injection of CCK compared with pre‐injected levels (203.3 ± 1 pg/mL). These results showed for the first time, that intravenous bolus injection of CCK increased ghrelin secretion in ruminants. In contrast, injection of ghrelin did not change CCK secretion. Administration of ghrelin or CCK has no effect on plasma OXM concentrations. In conclusion, our results show that administration of CCK increased ghrelin secretion but did not affect OXM release in ruminants. Ghrelin did not affect the secretions of CCK and OXM.  相似文献   
138.

Objective

N-butane and n-pentane can both produce general anesthesia. Both compounds potentiate γ-aminobutyric acid type A (GABAA) receptor function, but only butane inhibits N-methyl-d-aspartate (NMDA) receptors. It was hypothesized that butane and pentane would exhibit anesthetic synergy due to their different actions on ligand-gated ion channels.

Study design

Prospective experimental study.

Animals

A total of four Xenopus laevis frogs and 43 Sprague–Dawley rats.

Methods

Alkane concentrations for all studies were determined via gas chromatography. Using a Xenopus oocyte expression model, standard two-electrode voltage clamp techniques were used to measure NMDA and GABAA receptor responses in vitro as a function of butane and pentane concentrations relevant to anesthesia. The minimum alveolar concentrations (MAC) of butane and pentane were measured separately in rats, and then pentane MAC was measured during coadministration of 0.25, 0.50 or 0.75 times MAC of butane. An isobole with 95% confidence intervals was constructed using regression analysis. A sum of butane and pentane that was statistically less than the lower-end confidence bound isobole indicated a synergistic interaction.

Results

Both butane and pentane dose-dependently potentiated GABAA receptor currents over the study concentration range. Butane dose-dependently inhibited NMDA receptor currents, but pentane did not modulate NMDA receptors. Butane and pentane MAC in rats was 39.4 ± 0.7 and 13.7 ± 0.4 %, respectively. A small but significant (p < 0.03) synergistic anesthetic effect with pentane was observed during administration of either 0.50 or 0.75 × MAC butane.

Conclusions

Butane and pentane show synergistic anesthetic effects in vivo consistent with their different in vitro receptor effects.

Clinical relevance

Findings support the relevance of NMDA receptors in mediating anesthetic actions for some, but not all, inhaled agents.  相似文献   
139.
In this study, plasma MMP‐9 activity was evaluated in cats with lymphoma. Plasma samples were obtained from 26 cats with lymphoma before treatment. From 13 of the included 26 cats, plasma samples were obtained 4 weeks after the initiation of treatment. Plasma samples were also obtained from 10 healthy cats as a control. Plasma MMP‐9 activity was examined by gelatin zymography and semi‐quantitative value (arbitrary unit; a.u.) for each sample was calculated. Relatively high levels of MMP‐9 were observed in cats with lymphoma compared with those in healthy control cats. MMP‐9 quantification through zymography showed significantly higher activity in cats with lymphoma (median, 0.63 a.u.; range, 0.23–3.24 a.u.) than in healthy controls (0.22 a.u.; 0.12–0.46 a.u.; P < 0.01). MMP‐9 activities were significantly different before (0.73 a.u.; 0.30–3.24 a.u.) and after treatment (0.50 a.u.; 0.14–1.32 a.u.; P = 0.017). Measuring plasma MMP‐9 activity in cats with lymphoma may become an appropriate monitoring tool for feline lymphoma.  相似文献   
140.
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