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41.
Effect of an interfering substance on determination of potassium by ion-specific potentiometry in animal urine 总被引:1,自引:0,他引:1
Analytical characteristics of photometry and ion-specific potentiometry for urine from sheep, horses, cows, dogs, and cats were determined, using solutions of sodium and potassium chloride. The performance of both methods were acceptable, but the ion-specific potentiometer (in the mode for urine analysis) was superior in terms of linearity of response and correlation between actual vs measured concentrations. Coefficients of variation of either method for repeated analyses of various concentrations of sodium and potassium were always less than 2.5%. The measurement of sodium concentration in urine samples correlated well between both methods for samples from sheep, horses, cows, dogs, and cats. In contrast, measurement of potassium concentrations in urine samples from sheep, horses, cows, and cats was underestimated consistently by ion-specific potentiometry. The magnitude of the apparent error was variable between species and was often increased with greater urine potassium concentrations. These phenomena were not seen in urine samples from dogs. Sequential dilution of urine samples from sheep before analysis reduced the magnitude of the error observed by ion-specific potentiometry. Seemingly, an equilibrium process existed in which potassium was bound by an anionic or zwitterionic chemical and was sequestered from interaction with the ion-specific electrode. Ultrafiltration experiments indicated the putative potassium chelator was a low molecular weight compound. 相似文献
42.
Iron deficiency anemia was identified and characterized in three 14 to 29-month-old male llamas (llama Nos. 1-3) from separate herds in Colorado. The identification of iron deficiency anemia was based on hypoferremia (serum iron = 20-60 micrograms/dl), erythrocytic features, and hematologic response to iron therapy. The anemia was moderate and nonregenerative and characterized by erythrocyte hypochromia, microcytosis (mean cell volume = 15-18 fl), and decreased mean corpuscular hemoglobin concentration (36.0-41.0 g/dl). Morphologic features unique to llamas with iron deficiency anemia included irregular distribution of hypochromia within erythrocytes and increased folded cells and dacryocytes. The cause of iron deficiency was not determined. The llamas were treated with various doses and schedules of parenteral iron dextran. Two of the llamas were monitored for up to 14 months after the start of iron therapy and experienced increases in hematocrit and mean cell volume values. In one llama, progressive replacement of microcytic cells with normal cells was visualized on sequential erythrocyte volume distribution histograms following iron therapy. 相似文献
43.
Jaumann R Williams DA Buczkowski DL Yingst RA Preusker F Hiesinger H Schmedemann N Kneissl T Vincent JB Blewett DT Buratti BJ Carsenty U Denevi BW De Sanctis MC Garry WB Keller HU Kersten E Krohn K Li JY Marchi S Matz KD McCord TB McSween HY Mest SC Mittlefehldt DW Mottola S Nathues A Neukum G O'Brien DP Pieters CM Prettyman TH Raymond CA Roatsch T Russell CT Schenk P Schmidt BE Scholten F Stephan K Sykes MV Tricarico P Wagner R Zuber MT Sierks H 《Science (New York, N.Y.)》2012,336(6082):687-690
Vesta's surface is characterized by abundant impact craters, some with preserved ejecta blankets, large troughs extending around the equatorial region, enigmatic dark material, and widespread mass wasting, but as yet an absence of volcanic features. Abundant steep slopes indicate that impact-generated surface regolith is underlain by bedrock. Dawn observations confirm the large impact basin (Rheasilvia) at Vesta's south pole and reveal evidence for an earlier, underlying large basin (Veneneia). Vesta's geology displays morphological features characteristic of the Moon and terrestrial planets as well as those of other asteroids, underscoring Vesta's unique role as a transitional solar system body. 相似文献
44.
Abdominal emergencies in cattle. 总被引:1,自引:0,他引:1
45.
Morin DE Garry FB Weiser MG 《Veterinary clinical pathology / American Society for Veterinary Clinical Pathology》1993,22(3):81-86
Hematologic abnormalities consistent with iron deficiency anemia were experimentally induced in two healthy llamas by repeated phlebotomy. Hematologic abnormalities included erythrocyte microcytosis and hypochromia, decreased hemoglobin concentration, hypoferremia, and decreased transferrin saturation. Erythrocyte volume distribution histograms were more sensitive than mean corpuscular volume values for detection of microcytosis. Hypochromia, which was often eccentric, was morphologically observed on Wright-Giemsa-stained blood films. Frequent folded erythrocytes and dacryocytes were also noted on the blood films. Hematologic abnormalities resolved rapidly after cessation of blood removal, without parenteral iron supplementation. 相似文献
46.
Initial phylogenetic comparisons based on a region of the DNA polymerase of seven herpes-like viruses found in sturgeons in North America and Europe indicated the presence of three distinct clades. A revised phylogenetic analysis of the same viruses, based on corrected DNA polymerase sequences and newly obtained sequence data from the putative ATP subunit of the terminase gene, indicate only two clades. These two clades correspond to the historical designations given to these herpes-like viruses from white sturgeon Acipenser transmontanus: white sturgeon herpesvirus type 1 (WSHV-1) and type 2 (WSHV-2). The identification of putative terminase gene sequences for all seven herpes-like viruses from sturgeons confirms their affinity with the family Herpesviridae (because this gene is unique to herpesviruses) and more distantly with T4-like bacteriophages. The two clades of sturgeon herpesviruses are therefore appropriately designated as Acipenserid herpesviruses 1 and 2, which correspond to the previous common names of white sturgeon herpesvirus types 1 and 2. 相似文献
47.
Bacteria of the family Chlamydiaceae are obligate intracellular pathogens of human and animals. Chlamydophila pecorum is associated with different pathological conditions in ruminants, swine and koala. To characterize a coding tandem repeat (CTR) identified at the 3' end of incA gene of C. pecorum, 51 strains of different chlamydial species were examined. The CTR were observed in 18 of 18 tested C. pecorum isolates including symptomatic and asymptomatic animals from diverse geographical origins. The CTR were also found in two strains of C. abortus respectively isolated from faeces from a healthy ewe and from a goat belonging to asymptomatic herds, but were absent in C. abortus strains isolated from clinical disease specimens, and in tested strains of C. psittaci, C. caviae, C. felis and C. trachomatis. The number of CTR repeats is variable and encode several motifs that are rich in alanine and proline. The CTR-derived variable structure of incA, which encode the Chlamydiaceae-specific type III secreted inclusion membrane protein, IncA, may be involved in the adaptation of C. pecorum to its environment by allowing it to persist in the host cell. 相似文献
48.
Dennis MM Antognoli MC Garry FB Hirst HL Lombard JE Gould DH Salman MD 《Veterinary microbiology》2008,131(1-2):154-163
Disseminated infection (DI) of Mycobacterium avium subspecies paratuberculosis (MAP) in cattle may impair cow health, potentiate spread of disease, and is a potential food-safety risk. The objectives of this study were to determine the association between severity of histologic enteric lesions and the occurrence of DI, clinical signs, and positive fecal culture and serum ELISA results. Bacteriologic fecal culture and serum ELISA were performed on 40 dairy cows from MAP-infected herds. Cows were classified as having DI if MAP was isolated from any of 11 extra-intestinal tissues collected postmortem. A grade of 0-3, corresponding to the severity of histologically evident granulomatous inflammation was determined for sections of ileum, jejunum, mesenteric lymph node, and ileocolic lymph node. An overall intestinal inflammation (OII) grade of 0-3 was assigned to each cow. The proportion of cows with DI increased with tissue-specific lesion grade and OII grade. All cows with grade 3 inflammation in any single tissue had DI, however, some cows with DI had grade 1 inflammation or no lesions. In general, there was a positive association between OII grade and clinical signs, gross enteric lesions, and positive ELISA and fecal culture results. However, 12% of OII grade 0 cows had clinical signs (explained by other conditions recognized with necropsy), and the proportion of positive ELISA results was lower for OII grade 3 cows relative to grade 2 cows. Although MAP dissemination may occur early in the disease process, histopathology of intestinal tissues may be used to detect a substantial proportion of DI cows. 相似文献
49.
Involvement of microbial respiratory pathogens in acute interstitial pneumonia in feedlot cattle 总被引:1,自引:0,他引:1
Loneragan GH Gould DH Mason GL Garry FB Yost GS Miles DG Hoffman BW Mills LJ 《American journal of veterinary research》2001,62(10):1519-1524
OBJECTIVE: To evaluate viral and bacterial respiratory pathogens and Mycoplasma spp isolated from lung tissues of cattle with acute interstitial pneumonia (AIP) and cattle that had died as a result of other causes. SAMPLE POPULATION: 186 samples of lung tissues collected from cattle housed in 14 feedlots in the western United States. PROCEDURE: Lung tissues were collected during routine postmortem examination and submitted for histologic, microbiologic, and toxicologic examinations. Histologic diagnoses were categorized for AIP, bronchopneumonia (BP), control samples (no evidence of disease), and other disorders. RESULTS: Cattle affected with AIP had been in feedlots for a mean of 1272 days before death, which was longer than cattle with BP and control cattle. Detection of a viral respiratory pathogen (eg, bovine respiratory syncytial virus [BRSV], bovine viral diarrhea virus, bovine herpesvirus 1, or parainfluenza virus 3) was not associated with histologic category of lung tissues. Bovine respiratory syncytial virus was detected in 8.3% of AIP samples and 24.0% of control samples. Histologic category was associated with isolation of an aerobic bacterial agent and Mycoplasma spp. Cattle with BP were at greatest risk for isolation of an aerobic bacterial agent and Mycoplasma spp. CONCLUSIONS AND CLINICAL RELEVANCE: Analysis of these results suggests that AIP in feedlot cattle is not a consequence of infection with BRSV. The increased, risk of isolation of an aerobic bacterial agent from cattle with AIP, compared with control cattle, may indicate a causal role or an opportunistic infection that follows development of AIP. 相似文献
50.
Cotton RG Auerbach AD Axton M Barash CI Berkovic SF Brookes AJ Burn J Cutting G den Dunnen JT Flicek P Freimer N Greenblatt MS Howard HJ Katz M Macrae FA Maglott D Möslein G Povey S Ramesar RS Richards CS Seminara D Smith TD Sobrido MJ Solbakk JH Tanzi RE Tavtigian SV Taylor GR Utsunomiya J Watson M 《Science (New York, N.Y.)》2008,322(5903):861-862
An ambitious plan to collect, curate, and make accessible information on genetic variations affecting human health is beginning to be realized. 相似文献