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51.
Background: It has been speculated that renal disease can be identified through the detection and quantification of microalbuminuria, however, reliable measurement of albuminuria in any quantity can be challenging. Recently, a new point‐of‐care immunoassay was validated for the specific detection of microalbuminuria and early renal disease in dogs. Objectives: The goal of this study was to determine if measurement of microalbuminuria by the point‐of‐care immunoassay correlated with results from routine semiquantitative methods for detecting proteinuria in dogs. Methods: One hundred and thirty‐eight urine samples, from 133 different dogs, submitted for urinalysis to the Clinical Pathology Laboratory at the University of Missouri‐Columbia Veterinary Medical Teaching Hospital were eligible for the study. Samples that contained >20 RBC/high power field (hpf) or >20 WBC/hpf were excluded, as were samples with insufficient volume to complete all tests. All samples were evaluated with a urinary dipstick with or without a sulfosalicylic acid turbidimetric test, a urine protein:creatinine (UPC) ratio, and the immunoassay for microalbuminuria. Data were analyzed by the Spearman rank order correlation. Results: Microalbuminuria results correlated significantly with those of the dipstick (r= 0.715), sulfosalicylic acid test (r= 0.742), and UPC ratio (r= 0.830). Correlation between the immunoassay and UPC ratio was the same (r= 0.830) when only samples with trace or 1+ proteinuria by dipstick were analyzed (n = 51). Conclusions: The point‐of‐care immunoassay results for microalbuminuria correlated with the results of semiquantitative methods for detecting total proteinuria in dogs. Routine methods for canine proteinuria appear to be adequate for determining whether further testing for renal disease is warranted.  相似文献   
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We developed an analytical method using an on-line column-switching liquid chromatography with triple quadrupole mass spectrometry (LC/MS/MS) for quantifying multiple steroids in serum. Using the developed method, we evaluated the serum concentration of nine steroids (cortisol, corticosterone, cortisone, 11-deoxycortisol, 21-deoxycortisol, deoxycorticosterone, progesterone, 17α-OH-progesterone and aldosterone) in dogs with hyperadrenocorticism (HAC). Serum was mixed with stable isotope internal standards and thereafter purified by the automated column-switching system. The limit of detection ranged 2–16 pg/ml for nine steroids. In the baseline samples, five steroids (cortisol, corticosterone, cortisone, 11-deoxycortisol, and 17α-OH-progesterone) were detected in all dogs. The concentrations of cortisone, 11-deoxycortisol, and 17α-OH-progesterone in dogs with HAC (n=19) were significantly higher those in dogs without HAC (n=15, P<0.02). After the adrenocorticotropic hormone stimulation test, six steroids (cortisol, corticosterone, cortisone, 11-deoxycortisol, 17α-OH-progesterone, and deoxycorticosterone) were above the limit of quantification in all dogs. Cortisol, corticosterone, cortisone, and deoxycorticosterone concentrations of dogs with HAC were significantly higher than those of dogs without HAC (P<0.02). In addition, 11-deoxycortisol and 17α-OH-progesterone concentration was higher in dogs with HAC than in dogs without HAC (P=0.044 and P=0.048, respectively). The on-line column-switching LC/MS/MS would be feasible for measuring multiple steroids in dog serum. The results suggest that cortisone, 11-deoxycortisol, and 17α-OH-progesterone would be related to HAC. Further studies are warranted to assess the clinical feasibility of steroid profile in dogs with HAC.  相似文献   
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Objective   To describe the structure of the Australian poultry industry and discuss the potential for highly pathogenic avian influenza (HPAI) to spread between Australian poultry farms.
Procedure   High densities of poultry farms, frequent contacts between farms by service providers, the supply of live poultry markets (LPM) and the presence of free-range duck flocks in affected regions have been identified as risk factors for the spread of HPAI between flocks in outbreaks causing the death or destruction of over 1 million poultry overseas. Data on 1,594 commercial Australian chicken meat, chicken egg, duck and turkey farms were collected by a telephone questionnaire of farm managers to assess the risk of a HPAI outbreak in Australia.
Results and Discussion   Five regions of Australia had farm densities comparable to overseas regions that experienced widespread HPAI. Common service providers routinely contacted different classes and types of farms over wide geographic areas. However, no responding farms supplied LPM and the majority of duck farms did not produce free-range ducks.
Conclusion   Outbreaks of HPAI have the potential to cause serious impacts on the Australian poultry industry. The risk posted by LPM and free-range ducks is limited, but the movement of genetic stock and common service providers could spread infection between companies, industries or geographical regions. Biosecurity measures are therefore considered critical to limit the secondary spread of infection should an outbreak occur.  相似文献   
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The aim of this work was to determine the enzymatic activity of phosphofructokinase (PFK), malate dehydrogenase (MDH) and isocitrate dehydrogenase (IDH) in boar spermatozoa and study their participation in bicarbonate‐induced capacitation and follicular fluid‐induced acrosome reaction. Enzymatic activity of these enzymes was determined spectrophotometrically in extracts of boar spermatozoa. Sperm suspensions were incubated in the presence of bicarbonate (40 mM), a well‐known capacitation inducer, or follicular fluid (30%), as an acrosome reaction inducer, and different concentrations of oxoglutarate, oxalomalate and hydroxymalonate, inhibitors of PFK, IDH and MDH, respectively. Capacitation percentages were determined by the fluorescence technique of chlortetracycline (CTC), and true acrosome reaction was determined by trypan blue and differential–interferential contrast, optical microscopy. The activity of PFK in boar spermatozoa enzymatic extracts was 1.70 ± 0.19 U/1010 spermatozoa, the activity of NAD‐ and NADP‐dependent IDH was 0.111 ± 0.005 U/1010 and 2.22 ± 0.14 U/1010 spermatozoa, respectively, and the activity of MDH was 4.24 ± 0.38 U/1010 spermatozoa. The addition of the specific inhibitors of these enzymes prevented sperm capacitation and decreased sperm motility during capacitation and inhibited the acrosome reaction (AR), without affecting the sperm motility during this process. Our results demonstrate the participation of PFK, IDH and MDH in bicarbonate‐induced capacitation and follicular fluid‐induced acrosome reaction in boar spermatozoa, contributing to elucidate the mechanisms that produce energy necessary for these processes in porcine spermatozoa.  相似文献   
56.
Seminal plasma (SP) contains several types of compounds derived from the epididymides and accessory glands. The aim of this study was to examine the protein composition of different ejaculate fractions. Trial I: fractionated ejaculates were collected from two normal and two subfertile stallions. Samples containing pre‐sperm fluid and the first sperm‐rich jets (HIGH‐1), the main sperm‐rich portion (HIGH‐2), the jets with low sperm concentrations (LOW), and a combined whole‐ejaculate (WE) sample was centrifuged, and the SP was filtered and frozen. A part of each SP sample was stored (5°C, 24 h) with spermatozoa from HIGH‐2 and skim milk extender. Sperm motility was evaluated after storage in extender mixed with the stallion’s own SP or SP from one of the other stallions (sperm from a normal stallion stored in SP from a subfertile stallion and vice versa). Protein composition was analysed using reverse‐phase liquid chromatography (RP‐HPLC), N‐terminal sequencing and mass spectrometry. The area‐under‐the‐curve (AUC) was used for quantitative comparison of proteins within fractions. Trial II: semen samples were collected from seven stallions. Fractions with the highest (HIGH) and lowest (LOW) sperm concentrations and WE samples were examined using SDS‐PAGE and densitometry. No significant differences emerged between fractions in the AUC‐values of the Horse Seminal Protein‐1 (HSP‐1) and HSP‐2 peaks, or the peak containing HSP‐3 and HSP‐4 (HSP‐3/4). Levels of HSP‐1, HSP‐2 and HSP‐3/4 were not significantly correlated with total sperm motility, progressive sperm motility or average path velocity after storage. Significant differences between ejaculate fractions in the amount of different protein groups present in SP were not found in Trial I; but in Trial II, the proteins in the 60–70 kDa range were more abundant in LOW than in HIGH and WE, indicating that this band contained proteins derived mainly from the seminal vesicles, which produce most of the SP in LOW.  相似文献   
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An investigation was made to determine possible effects of gypsum and sulfur for control of common scab of potato [Streptomyces scabies (Thaxt.) Waksman and Henrici] in a highly buffered calcareous soil. This investigation included a comparison of the effectiveness of gypsum and sulfur with Terraclor and Terraclor Super-X. Both gypsum and sulfur reduced potato scab and measurements indicate that change of soil pH was slight (0.1–0.4 pH reduction). Band applications of sulfur in the sulfate (gypsum) or elemental form were effective at 600 lbs/A (672.5 Kg/ha) but not at lower rates. The weight of tubers thrown out of grade with scab was reduced by 53% with the effective sulfur rate. Treatment effects of gypsum (600 lb S/A-672.5 Kg/ha) were not significantly different from sulfur dust (600 lb/A-672.5 Kg/ha), Terraclor or Terraclor Super-X (both at 25.0 lb PCNB/A-28.0 Kg/ha). Tissue analyses of tuber peelings showed a significant reduction in calcium from treatments involving sulfur and gypsum, indicating that calcium levels in tuber peelings were positively correlated with scab susceptibility.  相似文献   
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