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971.
Gregory B. Daniel DVM MS Robert Denovo DVM MS A. Eric Schultze DVM PHD Dorothy Schmidt BS Gary T. Smith MD 《Veterinary radiology & ultrasound》1998,39(4):375-383
The extraction of the hepatobiliary radiopharmaceutical 99m Tc-mebrofenin ( Choletec ) by the liver can be used to evaluate the severity of hepatocellular disease. The hepatic parenchymal cells extract mebrofenin from the blood by the same active transport mechanism as bilirubin. The ability of the liver to extract 99m Tc-membrofenin is a measure of hepatic parenchymal cell function. In this study, we induced hepatocellular disease by administration of a hepatotoxic drug and compared a direct method of determining the hepatic extraction of 99m Tc-membrofenin to hepatic extraction fraction derived from deconvolutional analysis. We also compared both methods of calculating the hepatic extraction of 99m Tc-membrofenin to liver histopathology. Hepatic extraction fraction derived from deconvolutional analysis correlated very well to the direct measurement technique (R=0.922, p<0.001). Both methods of determining hepatic extraction correlated well to quantitative histopathology, having the same correlation coefficient and p values. (R=-0.833, p=0.003). As the hepatic extraction 99m Tc-membrofenin decreased, the severity of the histopathologic lesions of the liver increased in a linear fashion. There was a significant correlation of the hepatic excretion T1/2 to quantititative histopathology (R=0.949, p<0.001). The hepatic excretion T1/2 increased as the severity of the histopathologic lesions of the liver increased. Hepatic extraction (HEF) and excretion of 99m Tc-membrofenin are good predictors of the severity of hepatocellular damage in toxic induced liver disease. This study helps validate the premise that HEF derived from deconvolutional analysis ois a good predictor of the actual first pass hepatic extraction of 99m Tc-membrofenin. 相似文献
972.
Daniel V. Hecht VMD MS Karin Allenspach DMV 《Journal of Veterinary Emergency and Critical Care》1998,8(1):49-54
A five year old mixed breed dog weighing 30 kg., presumptively ingested six to twelve 20 mg baclofen tablets four to six hours prior to admission. The dog had been ataxic and vocalizing at home but was stuporous on presentation. Toxic effects noted were hypothermia, hypertension and sedation, followed by prolonged agitation. Treatment consisted of administration of activated charcoal, fluid diuresis, sodium nitroprusside, and diazepam. Baclofen overdose has been reported frequently in humans, but this is the first report of it in a dog. (Vet Emerg & Crit Care, 1998; 8: 49–54) 相似文献
973.
Daniel J. Karen Robert Draughn Michael Fulton Philippe Ross 《Pesticide biochemistry and physiology》1998,60(3):167
Brain acetylcholinesterase (AChE) inhibition was measured during 4-week and 4-day episodic exposures to chlorpyrifos. Organisms were exposed to a seawater (−) control, an acetone (+) control (0.1%), and 0.625, 1.25, 2.5, 5.0, and 10.0 μg of chlorpyrifos L−1in each test. These episodic exposures significantly depressed AChE activity at 2.5, 5.0, and 10.0 μg L−1(weekly test) and at 1.25, 2.5, 5.0, and 10.0 μg L−1(daily test). Six-hour pulsed exposure to chlorpyrifos inhibited brain AChE activity at concentrations as low as 1. 25 μg L−1. Stress at failure of caudal vertebrae following episodic exposure was also tested. Analysis of samples from daily 6-h treatments found no differences after 2 days; however, vertebrae were significantly weaker (than controls) after 4 days. Analysis of weekly 6-h exposures found weaker caudal vertebrae after 2 weeks but not after 4 weeks. 相似文献
974.
While studying the suslik fleas in artificial nests planted in free nature, significant changes in the population dynamics of N. setosa, C. simplex and C. orientalis (from the spring build up to the autumnal peak and the decrease of flea number until the next spring) were noted. The predominance of females in the spring period was recorded in N. setosa. Significant seasonal changes in the number of engorged females of N. setosa and C. simplex and of C. orientalis males (the increase of engorged specimens in the spring and summer) were demonstrated. A significant predominance of females with mature eggs in the spring and summer and their negligible number in the autumn were found in N. setosa and C. simplex. 相似文献
975.
A total of 83 hosts of the order Passeriformes from Nepal were examined for nematodes. Nine of them were found to be infected with 4 nematode species, Capillaria exilis, C. ovopunctata, Capillaria sp. and Thominx rigidula. The last species is redescribed in detail. Three of the definitive hosts are new for the above-mentioned nematode species and this is the first recorded from Nepal. 相似文献
976.
The levels of N-acetyl-beta-D-glucosaminidase (NAGase) were measured in the endometrial epithelial tissue of the bovine uterus during the oestrous cycle and during pregnancy. NAGase levels were significantly (P<0.001) higher in the epithelial tissue of the cow's uterus during the luteal phase of the cycle and during pregnancy than during the non-luteal phase. There were significantly (P<0.001) higher mean NAGase values in the epithelial than the subepithelial layers of the uterus in the two cycle phases and in pregnancy. Leucocyte numbers were significantly (P<0.05 and P<0.001) higher in the cows' uteri during the non-luteal phase than during the luteal phase and pregnancy, respectively. It is concluded that the endometrial epithelial layer is significantly active in terms of NAGase release and that this may be related to increased progesterone concentrations. In addition, the epithelial tissue (not leucocytes) appears to be the main contributor to the total NAGase activity in uterine tissue. 相似文献
977.
This paper analyzes the interactions between land use and forest cover in the Upper Midwest, USA from 1970 to 1990. New data
are presented and interpreted to evaluate the effects of land-use changes, especially abandonment of agriculture and dispersed
development, on forest cover throughout the region. Forest-cover data were collected from Landsat satellite imagery and land
use was interpreted from aerial photographs for land parcels, based on archival maps of land ownership. In general, forest
cover increased throughout the region and throughout the period. Simultaneously, the area used for agriculture declined, much
of it being converted to natural uses, and the area of land in low density residential development increased. Forest cover
increased most rapidly on low density residential lands and in counties in which a large percentage of homes were for seasonal
use (i.e., vacation homes). The data suggest that the transformation of the region from an extractive (i.e., forestry and
agriculture) to a recreation-based service economy has played a significant role in the increasing forest cover observed throughout
the region.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
978.
We analyzed forest clearing and regrowth over a 23-year time period for 21 forest concession and management units within the
Maya Biosphere Reserve(MBR), Guatemala. The study area as a whole experienced a clearing rate of0.16%/year from 1974 through
1997. The overall clearing rate appears rather low when averaged over the entire study area over 23 years because most of
the reserve was inaccessible. However, despite the granting of legal protection to the MBR in 1990, clearing rates continued
to rise, with the highest rates occurring in the most recent time period in the analysis, 1995 to1997. Higher rates of clearing
relative to regrowth occurred in newly established communities and in the Reserve's buffer zone, where the clearing of high
forest was preferred for pasture development. Exploratory models were built and analyzed to examine the effects of various
landscape variables on forest clearing. The different units in the analysis showed different relationships of forest clearing
with variables such as forest cover type and distance to access(roads and river corridors). Where available, socio-economic
household survey data helped to explain patterns and trends observed in the time series Landsat imagery. A strong relationship
between forest clearing and distance to access was demonstrated. More clearing occurred further from roads during later time
periods as farmers moved deeper into the forest to find land to clear. Communities inside the MBR that were less dependent
on farming had forest clearing to regrowth ratios of one:one or less. These communities used fallow fields in greater proportions
than communities in the Reserve's buffer zone. General trends in clearing by forest cover type suggest a preference for clearing
high forest (bosque alto) types found on the higher elevation, better-drained soils, and fallow fields,and an avoidance of low-lying, seasonally flooded
terrain(bajos). Satellite remote sensing observations of forest clearing and regrowth patterns can provide an objective source of information
to complement socio-economic studies of the human driving forces in land cover and land use change.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
979.
Effect of adipose-derived nucleated cell fractions on tendon repair in horses with collagenase-induced tendinitis 总被引:1,自引:0,他引:1
Nixon AJ Dahlgren LA Haupt JL Yeager AE Ward DL 《American journal of veterinary research》2008,69(7):928-937
OBJECTIVE: To assess the potential of adipose-derived nucleated cell (ADNC) fractions to improve tendon repair in horses with collagenase-induced tendinitis. ANIMALS: 8 horses. PROCEDURES: Collagenase was used to induce tendinitis in the superficial digital flexor tendon of 1 forelimb in each horse. Four horses were treated by injection of autogenous ADNC fractions, and 4 control horses were injected with PBS solution. Healing was compared by weekly ultrasonographic evaluation. Horses were euthanatized at 6 weeks. Gross and histologic evaluation of tendon structure, fiber alignment, and collagen typing were used to define tendon architecture. Biochemical and molecular analyses of collagen, DNA, and proteoglycan and gene expression of collagen type I and type III, decorin, cartilage oligomeric matrix protein (COMP), and insulin-like growth factor-I were performed. RESULTS: Ultrasonography revealed no difference in rate or quality of repair between groups. Histologic evaluation revealed a significant improvement in tendon fiber architecture; reductions in vascularity, inflammatory cell infiltrate, and collagen type III formation; and improvements in tendon fiber density and alignment in ADNC-treated tendons. Repair sites did not differ in DNA, proteoglycan, or total collagen content. Gene expression of collagen type I and type III in treated and control tendons were similar. Gene expression of COMP was significantly increased in ADNC-injected tendons. CONCLUSIONS AND CLINICAL RELEVANCE: ADNC injection improved tendon organization in treated tendons. Although biochemical and molecular differences were less profound, tendons appeared architecturally improved after ADNC injection, which was corroborated by improved tendon COMP expression. Use of ADNC in horses with tendinitis appears warranted. 相似文献
980.
Joyner PH Jones MP Ward D Gompf RE Zagaya N Sleeman JM 《American journal of veterinary research》2008,69(1):13-22
OBJECTIVE: To compare induction and recovery characteristics and cardiopulmonary effects of isoflurane and sevoflurane in bald eagles. Animals-17 healthy adult bald eagles. PROCEDURES: Anesthesia was induced with isoflurane or sevoflurane delivered in oxygen via a facemask in a crossover design with 4 weeks between treatments. Eagles were intubated, allowed to breathe spontaneously, and instrumented for cardiopulmonary measurements. Time to induction, extubation, and recovery, as well as smoothness of recovery, were recorded. RESULTS: Administration of sevoflurane resulted in a significantly quicker recovery, compared with isoflurane. Temperature, heart rate, and respiratory rate significantly decreased over time, whereas systolic (SAP), diastolic (DAP), and mean arterial blood pressure (MAP) significantly increased over time with each treatment. Temperature, heart rate, SAP, DAP, and MAP were significantly higher with isoflurane. Blood pH significantly decreased, whereas PaCO(2) significantly increased over time with each treatment. Bicarbonate and total carbon dioxide concentrations significantly increased over time with each treatment; however, there was a significant time-treatment interaction. The PaO(2) and arterial oxygen saturation increased over time with isoflurane and decreased over time with sevoflurane with a significant time-treatment interaction. Six eagles developed cardiac arrhythmias with isoflurane, as did 4 with sevoflurane anesthesia. CONCLUSIONS AND CLINICAL RELEVANCE: Isoflurane and sevoflurane administration resulted in smooth, rapid induction of and recovery from anesthesia similar to other species. Isoflurane administration resulted in tachycardia, hypertension, and more arrhythmias, compared with sevoflurane. Sevoflurane was associated with fewer adverse effects and may be particularly beneficial in compromised bald eagles. 相似文献