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31.
  • 1. The brown meagre (Sciaena umbra) is a demersal sciaenid fish recognized as indicative of good environmental quality and is defined as an umbrella species for the ecological community of rocky coastal habitats. Sciaena umbra is classified as a Vulnerable fish species by the International Union for Conservation of Nature (IUCN) and knowledge on the distribution of its spawning habitats is essential for its conservation.
  • 2. Passive acoustic monitoring (PAM) is a suitable tool to monitor S. umbra distribution because of the high consistency, over space and time, of the communication sounds that this species emits during the reproductive period, with irregular or regular rhythms, or with calls merging into a chorus.
  • 3. During the summer of 2019, the presence of this species was investigated acoustically at 40 listening points distributed along the tidal inlets that connect the Venice lagoon with the open sea.
  • 4. Longer sounds, comprising a higher number of faster repeated pulses, were found during the chorus and were used as a proxy of spawning activity; similar sound features have been recorded in different captive Sciaenids during spawning.
  • 5. The three inlets were classified as more or less suitable for spawning on the basis of the vocal rhythms identified, demonstrating a clear preference along a north–south gradient and indicating higher spawning activity in the internal‐facing areas of the inlets, compared with the seaward‐facing areas. The chorus occurred in localized areas consistently throughout the breeding season, suggesting that spawning is concentrated in preferred areas.
  • 6. For the first time a relationship between the sound features and vocal rhythms of fish has been highlighted by an in situ study. This validates the use of the chorus as a reliable natural indicator of S. umbra breeding sites, and in turn suggests a potential non‐invasive approach based on PAM for mapping the key reproductive areas of this vulnerable species in the Mediterranean Sea.
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A 6-year-old spayed female ferret (Mustela putorius furo) exhibiting clinical signs of weakness, anorexia, lethargy, weight loss, and frequent urination was presented for a veterinary evaluation to determine the underlying cause of the aforementioned abnormal behavior and clinical condition. Physical examination revealed a large, firm, painless, movable subcutaneous mass at the base of the tail. Radiographic and ultrasound images confirmed the presence of a soft tissue mass compressing the sacrococcygeal vertebrae, but there was no evidence of metastatic lesions. Because of the poor prognosis and progressive deterioration of the animal's clinical condition, the ferret was humanely euthanized. Gross necropsy revealed a 4 × 4 × 3.5 cm, firm, yellow-tan, ovoid, subcutaneous mass wrapped around the rectum and the anus. The mass did not appear to breach the serosa. Evaluation of the abdominal cavity revealed a pale yellow liver, possibly associated with hepatic lipidosis with no gross evidence of metastasis in the body cavity. The histopathological features of the mass were consistent with a liposarcoma. To the best of the authors' knowledge, this is the first case of subcutaneous liposarcoma reported in a ferret.  相似文献   
34.
Orange juice is a source of antioxidants that might afford in vivo protection from oxidative stress. To test this hypothesis, we carried out a human intervention study with blood orange juice containing high amounts of vitamin C, anthocyanins, and carotenoids. Sixteen healthy female volunteers were enrolled in a crossover study and were given 600 mL/day of blood orange juice or a diet without juice for 21 days. Before and after each intervention period, plasma vitamin C, cyanidin-3-glucoside, and carotenoids were quantified. Furthermore, plasma antioxidant capacity, malondialdehyde concentration in plasma, 11-dehydrotromboxane B(2) urinary excretion, and lymphocyte DNA damage were evaluated as biomarkers of oxidative stress. Blood orange juice consumption determined a significant increase in plasma vitamin C, cyanidin-3-glucoside, beta-cryptoxanthin, and zeaxanthin. Also, lymphocyte DNA resistance to oxidative stress was improved whereas no effect was observed on the other markers that we analyzed. In turn, these results suggest that blood orange juice is a bioavailable source of antioxidants, which might moderately improve the antioxidant defense system; however, the long-term effects of its consumption are to be further investigated.  相似文献   
35.
A degenerate gas of identical fermions is brought to collapse by the interaction with a Bose-Einstein condensate. We used an atomic mixture of fermionic potassium-40 and bosonic rubidium-87, in which the strong interspecies attraction leads to an instability above a critical number of particles. The observed phenomenon suggests a direction for manipulating fermion-fermion interactions on the route to superfluidity.  相似文献   
36.
The objective of this study was to determine the effects of the administration of a high volume of isotonic crystalloid at a rapid rate on cardiovascular function in normovolemic, isoflurane-anesthetized dogs during induced hypotension.Using a prospective study, 6 adult dogs were induced to general anesthesia and cardiovascular and hematological values were measured while the dogs were maintained at 3 hemodynamic states: first during light anesthesia with 1.3% end-tidal isoflurane (ETI); then during a hypotensive state induced by deep anesthesia with 3% ETI for 45 min while administered 1 mL/kg body weight (BW) per minute of isotonic fluids; and then decreased to 1.6% ETI while receiving 1 mL/kg BW per minute of fluids for 15 min. End-tidal isoflurane (ETI) at 3.0 ± 0.2% decreased arterial blood pressure (ABP), cardiac index (CI), and stroke volume index (SVI), and increased stroke volume variation (SVV) and central venous pressure (CVP). Fluid administration during 3% ETI decreased only SVV and systemic vascular resistance index (SVRI), while CVP increased progressively. Decreasing ETI to 1.6 ± 0.1% returned ABP and SVI to baseline (ETI 1.3 ± 0.1%), while CI and heart rate increased and SVV decreased. There was significant progressive clinical hemodilution of hemoglobin (Hb), packed cell volume (PCV), total protein (TP), colloid osmotic pressure (COP), arterial oxygen content (CaO2), and central-venous oxygen content (CcvO2).High-volume, rapid-rate administration of an isotonic crystalloid was ineffective in counteracting isoflurane-induced hypotension in normovolemic dogs at a deep plane of anesthesia. Cardiovascular function improved only when anesthetic depth was reduced. Excessive hemodilution and its adverse consequences should be considered when a high volume of crystalloid is administered at a rapid rate.  相似文献   
37.
Many object-related actions can be recognized by their sound. We found neurons in monkey premotor cortex that discharge when the animal performs a specific action and when it hears the related sound. Most of the neurons also discharge when the monkey observes the same action. These audiovisual mirror neurons code actions independently of whether these actions are performed, heard, or seen. This discovery in the monkey homolog of Broca's area might shed light on the origin of language: audiovisual mirror neurons code abstract contents-the meaning of actions-and have the auditory access typical of human language to these contents.  相似文献   
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A city may become smart and green through strategic deployment of Information and Communication Technology infrastructure and services to achieve sustainability policy objectives in which trees have to be involved. Plants not only constitute green space useful to contrast urban pollution effects or provide ecosystemic benefits to residents but they can also be used as bioindicators and their involvement in communication networks can represent a significant contribution to build a smart, green city. The concept of the Internet of Things (IoT) envisages that objects that surround us will be connected and there are no reasons to exclude urban trees from among the “wired object”. Radio frequency identification devices (RFID) may represent a prerequisite of IoT application and they can be used for tree protection and management, thanks to tagging experience carried out on various plant species. RFID tags can be easily associated with plants, externally or internally. This latter approach is particularly indicated if the identification of trees needs to be secured since its production, eliminating the risk of tag losses or removal. Interesting applications may be derived by implementing RFID tags in biomonitoring systems in order to guarantee a real-time data communication in which tags may act as antennas for multifunctional green spaces. Moreover, the virtualization of green areas using sensors and mobile devices can lead to the desktop management of the urban green with the possibility of implementing a real-time navigation throughout the areas. A complex relational network in which data can be collected thanks to geospatial methods can be integrated by an IoT approach in which RFID-plants can play a significant role.  相似文献   
40.
The objective of this study was to compare the effect on the minimum alveolar concentration (MAC) of isoflurane when ketamine was administered either after or without prior determination of the baseline MAC of isoflurane in rabbits. Using a prospective randomized crossover study, 8 adult, female New Zealand rabbits were allocated to 2 treatment groups. Anesthesia was induced and maintained with isoflurane. Group 1 (same-day determination) had the MAC-sparing effect of ketamine [1 mg/kg bodyweight (BW) bolus followed by a constant rate infusion (CRI) of 40 μg/kg BW per min, given by intravenous (IV)], which was determined after the baseline MAC of isoflurane was determined beforehand. A third MAC determination was started 30 min after stopping the CRI. Group 2 (separate-day determination) had the MAC-sparing effect of ketamine determined without previous determination of the baseline MAC of isoflurane. A second MAC determination was started 30 min after stopping the CRI. In group 1, the MAC of isoflurane (2.15 ± 0.09%) was significantly decreased by ketamine (1.63 ± 0.07%). After stopping the CRI, the MAC was significantly less (2.04 ± 0.11%) than the baseline MAC of isoflurane and significantly greater than the MAC during the CRI. In group 2, ketamine decreased isoflurane MAC (1.53 ± 0.22%) and the MAC increased significantly (1.94 ± 0.25%) after stopping the CRI. Minimum alveolar concentration (MAC) values did not differ significantly between the groups either during ketamine administration or after stopping ketamine. Under the study conditions, prior determination of the baseline isoflurane MAC did not alter the effect of ketamine on MAC. Both methods of determining MAC seemed to be valid for research purposes.  相似文献   
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