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101.
Objective – To test whether an initial plasma lactate≥6.0 mmol/L is associated with the presence of macroscopic gastric wall necrosis and overall survival in dogs presenting with gastric dilatation‐volvulus (GDV). Additionally, if no association was identified we sought to identify a different predictive initial plasma lactate concentration and to examine whether serial plasma lactate concentrations provide better prediction of survival. Design – Retrospective study over a 5‐year period (2003–2007). Setting – Urban private referral small animal teaching hospital. Animals – Eighty‐four client‐owned dogs with a diagnosis of GDV and plasma lactate measurements. Interventions – None. Measurements and Main Results – There was no statistically significant relationship found between survival and the presence of macroscopic gastric wall necrosis with the initial plasma lactate≥6 mmol/L. There was a significant relationship between the initial plasma lactate >2.9 mmol/L for predicting necrosis and <4.1 mmol/L for predicting survival to discharge. Forty dogs that had an increased initial plasma lactate (>2.5 mmol/L) also had a subsequent plasma lactate measured within 12 hours of presentation, with 37/40 dogs surviving and 70% of these surviving dogs having the subsequent lactate decrease by≥50% within 12 hours. The 3/40 that died failed to decrease their plasma lactate by≥50% from the initial blood lactate. Conclusion – The results of this study indicate that an initial presenting plasma lactate concentration≥6.0 mmol/L is not predictive of macroscopic gastric wall necrosis or survival in dogs presenting with GDV. A decrease in plasma lactate concentrations≥50% within 12 hours may be a good indicator for survival. Limitations to the study include its retrospective nature, the small number of patients, and the number of dogs that were euthanized rather than allowed to progress to a natural outcome.  相似文献   
102.
This case series describes a rare entity, nasal angiofibroma, in 13 dogs that were presented to the University of Wisconsin, School of Veterinary Medicine from 1988 to 2000. All dogs in this case series presented with clinical signs and radiographic changes that were strongly suggestive of a locally invasive neoplasm. However, histopathology completed on transnostral core biopsy samples revealed benign appearing vascular proliferation with secondary lymphosuppurative inflammation was established despite cytologic criteria of malignancy present in five dogs. On the basis of the outcomes in this case series, nasal angiofibroma should be considered a differential for dogs presenting with clinical signs consistent with a malignant nasal tumour.  相似文献   
103.
A 14.5-kg, 13-year-old female spayed Cocker spaniel was evaluated because of episodic hind limb weakness. Results of examination were consistent with sick sinus syndrome with intermittent second-degree atrioventricular block. Transesophageal atrial pacing was successful in providing chronotropic support during permanent pacemaker implantation. Transesophageal atrial pacing appears to be a viable option for temporary atrial pacing in dogs with hemodynamically marked bradycardia without significant atrioventricular blockade.  相似文献   
104.
Between 1998 and 2009, the four tomato‐infecting begomovirus species detected in Taiwan were Ageratum yellow vein Hualien virus (AYVHuV), Tomato leaf curl Taiwan virus (ToLCTWV), Tomato yellow leaf curl Thailand virus (TYLCTHV) and a newly defined species Tomato leaf curl Hsinchu virus (ToLCHsV). AYVHuV was detected occasionally in 2003 and ToLCHsV only in 2000–2001, whilst ToLCTWV was detected throughout the period. TYLCTHV was first detected in 2005. Between 1998 and 2005, >99% of the begomovirus‐positive samples were infected with ToLCTWV. In 2007 in western Taiwan, 16% of the positive samples were infected with ToLCTWV, 35% with TYLCTHV and 49% with mixed infection (ToLCTWV/TYLCTHV). In contrast, in eastern Taiwan the proportions were 84% ToLCTWV, 2% TYLCTHV and 14% mixed infection. However, throughout Taiwan in 2008–2009, most positive samples were either identified as TYLCTHV (51%) or mixed infection (ToLCTWV/TYLCTHV; 41%), and only 8% were ToLCTWV. This shows a clear trend of shifting from ToLCTWV to TYLCTHV and mixed infection over a short time period in Taiwan. Sequence analyses indicated that tomato‐infecting AYVHuV, an apparent recombinant between ToLCTWV and AYVHuV from Ageratum, represents a new strain Hsinchu. TYLCTHV Taiwan isolates were highly similar to each other, whereas ToLCTWV isolates had greater diversity and were classified into three strains which had one country‐wide and two local distributions. ToLCTWV and TYLCTHV were confirmed as monopartite and bipartite begomoviruses, respectively, by agroinfection followed by transmission with Bemisia tabaci biotype B. In addition, TYLCTHV was found to be mechanically transmissible together with viral DNA‐B.  相似文献   
105.

Background

Safflower (Carthamus tinctorius L.) is a difficult crop to genetically transform being susceptible to hyperhydration and poor in vitro root formation. In addition to traditional uses safflower has recently emerged as a broadacre platform for the production of transgenic products including modified oils and pharmaceutically active proteins. Despite commercial activities based on the genetic modification of safflower, there is no method available in the public domain describing the transformation of safflower that generates transformed T1 progeny.

Results

An efficient and reproducible protocol has been developed with a transformation efficiency of 4.8% and 3.1% for S-317 (high oleic acid content) and WT (high linoleic acid content) genotypes respectively. An improved safflower transformation T-DNA vector was developed, including a secreted GFP to allow non-destructive assessment of transgenic shoots. Hyperhydration and necrosis of Agrobacterium-infected cotyledons was effectively controlled by using iota-carrageenan, L-cysteine and ascorbic acid. To overcome poor in vitro root formation for the first time a grafting method was developed for safflower in which ~50% of transgenic shoots develop into mature plants bearing viable transgenic T1 seed. The integration and expression of secreted GFP and hygromycin genes were confirmed by PCR, Southern and Western blot analysis. Southern blot analysis in nine independent lines indicated that 1-7 transgenes were inserted per line and T1 progeny displayed Mendelian inheritance.

Conclusions

This protocol demonstrates significant improvements in both the efficiency and ease of use over existing safflower transformation protocols. This is the first complete method of genetic transformation of safflower that generates stably-transformed plants and progeny, allowing this crop to benefit from modern molecular applications.
  相似文献   
106.
Plants can play an important role in wastewater treatment and water reuse in terrestrial and space systems. Chive growth in biologically treated graywater, simulating the anticipated early planetary base graywater, was evaluated in this study for NASA. Phytotoxicity due to physiochemical parameters such as ammonium-nitrogen (NH4 +-N), nitrite-nitrogen (NO2 ?-N), pH, and sodium (Na+) was assessed using a series of hydroponic experiments in an environmentally controlled growth chamber. Nitrification in wastewater was observed in all graywater treatments, which converted NO2 ?-N (a toxic form of nitrogen) and NH4 +-N (toxic at high concentrations) to nitrate-nitrogen (NO3 ?-N) (preferred N form for plant uptake). Irrespective of the increase in the NO3 -N concentration due to nitrification, chives in the wastewater treatments typically had poor or no growth. The high levels of Na+ present in the graywater treatments affected potassium uptake and may have affected other nutrient uptake. The impact of nitrification on wastewater pH and NO2 ?-N toxicity is believed to be the critical factor affecting chive growth and may hinder the use high nitrogen waste streams for plant growth unless NO2 ?-N concentrations are controlled during biological treatment of graywater.  相似文献   
107.
Concerns have been raised of possible human food chain transfer of lead and arsenic from crops grown on orchard soils with histories of lead arsenate use. The objective of this study was to determine arsenic and lead uptake by three cultivars of carrots grown on four orchard soils with histories of lead arsenate use. Total concentrations of arsenic and lead in these soils ranged from 93 to 291 and from 350 to 961 mg kg?1 for arsenic and lead, respectively. Arsenic in peeled carrot ranged from 0.38 to 1.64 mg kg?1, while lead ranged from 2.67 to 7.3 mg kg?1 dry weight. This study demonstrated that carrots will accumulate arsenic and lead in the root, which may become a human health risk when consumed. However, further studies are needed to determine what fraction of arsenic and lead in these carrots are bioavailable to humans when consumed.  相似文献   
108.
The interaction between four flavonoids (catechin, epicatechin, rutin, and quercetin) and bovine serum albumin (BSA) was investigated using tryptophan fluorescence quenching. Quenching constants were determined using the Stern-Volmer equation to provide a measure of the binding affinity between the flavonoids and BSA. The binding affinity was strongest for quercetin and ranked in the order quercetin > rutin > epicatechin = catechin. The pH in the range of 5-7.4 does not affect significantly (p < 0.05) the association of rutin, epicatechin, and catechin with BSA, but quercetin exhibited a stronger affinity at pH 7.4 than at lower pH (p < 0.05). Quercetin has a total quenching effect on BSA tryptophan fluorescence at a molar ratio of 10:1 and rutin at approximately 25:1. However, epicatechin and catechin did not fully quench tryptophan fluorescence over the concentration range studied. Furthermore, the data suggested that the association between flavonoids and BSA did not change molecular conformation of BSA and that hydrogen bonding, ionic, and hydrophobic interaction are equally important driving forces for protein-flavonoid association.  相似文献   
109.
Each of seven mares was given an intravenous (IV) injection of 40% dimethyl sulfoxide (DMSO) at a dosage of 1 g/kg, over 35 min, immediately followed by a single IV injection of a trimethoprim (TMP) and sulfamethoxazole (SMZ) combination (SMZ 83%, TMP 17%) at a combined dosage of 44 mg/kg (7.48 mg/kg TMP; 36.52 mg/kg SMZ). Each horse served as its own control and was alternately treated with an identical dose of TMP-SMZ treatment alone at least seven days following or preceding the DMSO and TMP-SMZ treatment. Serum and cerebrospinal fluid (CSF) concentrations of TMP and SMZ were measured over a six hour period. Dimethyl sulfoxide treatment caused no significant difference in the mean serum concentration of SMZ or in the mean CSF concentrations of TMP or SMZ. The mean serum concentration of TMP was significantly (p less than 0.05) increased at the two, four and six hour sampling time in the mares receiving pretreatment with DMSO. The clearance of TMP was also significantly (p less than 0.05) decreased from 675 mL/h/kg to 327 mL/h/kg by DMSO administration. Concentrations of TMP and SMZ in the CSF in both treatment groups exceeded the minimum inhibitory concentrations for many common bacterial pathogens of equine origin. In addition, CSF concentration of TMP exceeded the serum concentrations required for 50% inhibition of dihydrofolate reductases of protozoan origin. Serum TMP and SMZ concentration were similar to those reported to be effective against Toxoplasma gondii in in vitro studies on the killing or inhibition of the organism.  相似文献   
110.
The inhibition of eel acetylcholinesterase by the 4-nitrophenyl esters of 2-furyl(methyl)-, methyl(2-thienyl)-, di-2-furyl-, and di-2-thienylphosphinic acid (I, II, III, and IV, respectively) was investigated at pH 6.90 in 0.067 M phosphate buffer (25.0°C) using stopped-flow instrumentation and automated data processing. Our evaluation of the dissociation constant, Kd, the unimolecular bonding rate constant, k2, and the bimolecular reaction constant, ki, are the first reported values for these constants for alkyl/heteroaryl and diheteroaryl esters of phosphinic acids. The largest ki value (19,330 M?1 sec?1) was observed for the reaction of I with the enzyme. The order for the remaining three is II > IV > III. There is no direct relationship between the hydrolysis rates of the esters and their anticholinesterase activities on eel acetylcholinesterase. Likewise, there is no direct relationship between their anticholinesterase activities and the LD50 values in rats.  相似文献   
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