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91.

Context

Abundance and diversity of bumblebees have been declining over the past decades. To successfully conserve bumblebee populations, we need to understand how landscape characteristics affect the quantity and quality of floral resources collected by colonies and subsequently colony performance.

Objectives

We therefore investigated how amount and composition of pollen collected by buff-tailed bumblebee Bombus terrestris colonies was affected by the surrounding landscape (i.e. the proportion of forest, urban, semi-natural habitats) and how they were related to colony growth.

Methods

Thirty B. terrestris colonies were placed at grassland sites differing in surrounding landscape. Colonies were established in spring when availability of flowering plants was highest, and their weight gain was monitored for 1 month. We additionally recorded the quantity and compared plant taxonomic composition and nutritional quality (i.e. amino acid composition) of pollen stored.

Results

Bumblebee colonies varied little in the pollen spectra collected despite differences in surrounding landscape composition. They collected on average 80 % of pollen from woody plants, with 34 % belonging to the genus Acer. Early colony growth positively correlated with total amount of woody pollen and protein collected and decreased with increasing proportions of semi-natural habitats and total amino acid concentrations.

Conclusions

Our results suggest that woody plant species represent highly important pollen sources for the generalist forager B. terrestris early in the season. We further show that colony growth of B. terrestris is predominantly affected by the quantity, not quality, of forage, indicating that several abundant plant species flowering throughout the bumblebees’ foraging season may cover the colonies’ nutritional needs.
  相似文献   
92.
A 20-year-old gelding was diagnosed with peritonitis and severe reactive mesothelial hyperplasia. Exploratory laparotomy findings were suggestive of a neoplastic etiology; however, additional diagnostics ruled this out and the horse made a full recovery. This report demonstrates the difficulty and value of differentiating between reactive and neoplastic mesothelial processes.  相似文献   
93.
The objective of this study was to determine the characteristics based on ultrasonographic examination of the stomach, duodenum, jejunum, cecum, and peritoneal fluid in normal adult ponies. Abdominal ultrasonographic examination was performed in nine unsedated standing ponies. The duodenum was examined at three sites and the jejunum in 12 regions. Wall thickness, contractility, distention, and luminal contents were recorded. Stomach wall thickness and location, cecal wall thickness, and peritoneal fluid location and character were recorded. Statistical analysis was performed. Wall thicknesses (in cm) were 0.431 +/- 0.069 for the stomach, 0.188 +/- 0.033 for the duodenum (at all sites), 0.195 +/- 0.031 for the jejunum (at all regions), and 0.179 +/- 0.031 for the cecum. Duodenal contractions per minute were 3.78 +/- 1.10. The stomach spanned 5.14 +/- 0.9 intercostal spaces, with the 8th intercostal space being the most cranial and the 15th intercostal space being the most caudal space through which the stomach was identified. It was possible to identify the jejunum in all ponies dorsal to the left dorsal colon and from the ventral abdominal wall. Peritoneal fluid was identified in six ponies. Peritoneal fluid was usually seen transiently and most commonly in the ventral aspect of the abdominal cavity or around the duodenum. Overall, the ponie's abdominal ultrasonographic examinations revealed wall thicknesses that were less than the published normal ranges for horses. It appears that ponies may have increased duodenal contractility than horses and that the conformation of ponies may change the locations for imaging the stomach.  相似文献   
94.
Putative genetic markers have been associated with ETEC F4 (Mucine 4 [MUC4]; MUC4GG;CG as susceptible; MUC4CC as resistant) and F18 (Fucosyltransferase 1 [FUT1]; FUT1GG;AG as susceptible; FUT1AA as resistant) resistances respectively. In this study, 71 post‐weaning pigs were followed from d0 (35 days old) to d42 (77 days of age) to investigate the effect of MUC4 or FUT1 genotypes on the mid‐jejunal microbiota composition, pigs expression of genes related to inflammation (IL8, GPX2, REG3G, TFF3, CCL20 and LBPI) and glycomic binding pattern profile (Ulex europaeus agglutinin I [UEA] fucose‐binding lectin and peanut agglutinin [PNA] galactose‐specific), and on blood plasma targeted metabolomics profile, faecal score and performance parameters of growing healthy pigs. The MUC4 and FUT1 resistant genotypes improved the pigs’ growth performance and had firmed faecal score susceptible genotypes in d0–d21 period. Pigs with MUC4GG genotype had a higher jejunal expression of genes relate to immune function (CCL20 and REG3G) than MUC4CG and MUC4CC pigs (p < 0.05). MUC4CG pigs had higher expression of TFF3 (implicated in mucosal integrity) than MUC4GG and MUC4CC (p < 0.05). FUT1 influenced the alpha‐ and beta‐jejunal microbial indices. The FUT1AA group had a higher number of operational taxonomic units (OTUs) belonging to Lactobacillus genus, while FUT1GG group had a higher number of OTUs belonging to Veillonella genus. MUC4CC pigs had lower scores for UEA on brush borders and goblet cells in villi than MUC4GG (p < 0.05). FUT1AA pigs had lower UEA positivity and higher PNA positivity on brush borders and goblet cells than FUT1AG and FUT1GG (p < 0.05). Both FUT1 and MUC4 influenced the metabolic profile of healthy pigs. Results highlight the role of MUC4 and FUT1 on pig intestinal homoeostasis and improved the knowledge regarding the potential interaction between host genetics, gut microbiota composition and host metabolism in a healthy status.  相似文献   
95.
96.
Three levels (0, 1 and 2%) of conjugated linoleic acid (CLA) were combined with two levels (low and high) of monounsaturated fatty acids (MUFA) for pig feeding. Productive, carcass and meat quality traits were studied. Large White ♂ × Landrace × Large White ♀ gilts (= 288) weighting 70 kg were randomly allotted to 6 different feeding treatments and fed to a final average weight of 107 kg. Loins were taken from 48 animals (8 animals randomly selected from each treatment). No differences due to dietary CLA, MUFA or CLA × MUFA interaction were found on average daily gain, average daily consumption, feed conversion ratio, carcass yield, backfat thickness, loin weight, loin pH and loin colour. A significant increase in intramuscular fat content (= 0.010) and in saturated fatty acids (SFA) (< 0.001), and a decrease in MUFA (= 0.001) and desaturase indices were found as consequence of dietary CLA, regardless the MUFA level. Therefore, dietary CLA, MUFA and their interaction did not influence productive and carcass traits of pigs. However, the use of CLA for swine feeding increased the intramuscular fat content and modified the fatty acid profile, regardless the MUFA level of the diets.  相似文献   
97.
98.
A red-bellied piranha (Pygocentrus nattereri), kept as a pet by a private owner, was presented for multifocal ulcerative lesions. Lesion biopsies were collected under general anesthesia and submitted for histopathologic and microbiologic examination. Histological examination revealed a bacterial necrotizing ulcerative dermatitis. From cultural analysis of the biopsy, Aeromonas hydrophila and Edwardsiella ictaluri were isolated. Multidrug resistance was observed in both isolates, except for neomycin and ceftazidime. Intramuscular injections of ceftazidime 22 mg/kg were administered until complete healing of the wound, except for small dermal scars that remained following treatment. Given that the piranha was maintained alone since it was purchased, except for occasional feedings with fresh nonfrozen goldfish, horizontal transmission of the infection from the prey species was considered the source of infection.  相似文献   
99.
Different species have different sensitivity to heat waves; therefore, interspecific competition may affect the crop response to heat waves. We investigated the effects of heat waves on spring barley (Hordeum vulgare L.) grown with and without wild mustard (Sinapis arvensis L.) as well as the recovery of barleys from stress. The plants were exposed to a 7‐day 35/28ºC (day/night) heat wave at ambient CO2 (400 μmol/mol) and elevated CO2 (800 μmol/mol). All seedlings were rehydrated and returned to control conditions (21/14ºC, CO2 400 μmol/mol) after the cease of heat wave and grown for a 7‐day period of recovery. Heat wave had more pronounced negative effect on the barley's aboveground biomass under competition with mustard, whereas the response of root biomass was not influenced by the presence of weeds. The heat wave induced reductions in barley's photosynthetic rate, stomatal conductance and water use efficiency under interspecific competition were higher compared to monocultured conditions. Interspecific competition impaired and delayed the recovery of barley's biomass production and leaf gas exchange parameters after heat wave. Elevated CO2 slightly mitigated negative heat wave impact on the growth and leaf gas exchange parameters but had no effect during the recovery period.  相似文献   
100.
The roots of Annona cherimolia have been shown to contain the known tetrahydroprotoberberine alkaloids corytenchine (1) and isocoreximine (2), investigated for their cytotoxic properties.  相似文献   
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