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排序方式: 共有255条查询结果,搜索用时 15 毫秒
121.
Laura Johnson Kristina Simone John Cullen Ashley Talley Eli B. Cohen 《Veterinary radiology & ultrasound》2019,60(6):E62-E65
A 10‐week‐old spayed female German Shepherd Dog was presented for acute vomiting and diarrhea. There was no reported foreign body or toxin ingestion. Radiographs showed a severely (~11 × 7 cm), focally distended right abdominal intestinal segment containing gas and soft tissue material. Other small intestinal segments were segmentally gas distended. Celiotomy identified a ~9 cm focally dilated segment at the jejunoileal junction with no aborad luminal obstruction. Resection and anastomosis of the dilation was performed. Histopathology showed mild mucosal inflammation, but otherwise normal wall layering and autonomic ganglia. Radiographic and histopathologic findings were consistent with congenital segmental dilation of the intestine. 相似文献
122.
Effects of Interferon‐Tau and Steroids on Cytochrome P450 Activity in Bovine Endometrial Epithelial Cells
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The objective of the current study was to examine cyclooxygenase (COX), cytochrome P450 1A (CYP1A) and 2C (CYP2C) activity in bovine endometrial cell cultures following exposure to oxytocin (OT), interferon‐τ (IFN), estradiol (E2) and/or progesterone (P4). Bovine endometrial epithelial cells were treated with OT, IFN, a combination of OT+IFN or control (CON) media for 24 h. For the second experiment, cells were treated with E2, P4, a combination of E2 + P4 or CON media for 24 h. Treatments were performed in triplicate, and the experiment was repeated four times (n = 12 per treatment). Treatment with OT alone increased (p < 0.01) activity of COX compared with CON; however, OT alone did not alter activity of CYP1A (p = 0.55) or CYP2C (p = 0.46) compared with CON. Activity of CYP1A and CYP2C was decreased in cells exposed to IFN (p < 0.01) or OT+IFN (p < 0.01) compared with CON. Treatment with E2 alone did not alter activity of CYP1A (p = 0.64) or CYP2C (p = 0.06) compared with CON. Activity of CYP1A and CYP2C was decreased (p < 0.01) in P4 vs CON. In summary, IFN exposure, irrespective of OT treatment, decreased the activity of CYP1A and CYP2C. Activity of CYP1A was decreased following P4 treatment alone, while that of CYP2C was decreased following both P4 and E2 + P4 treatment. The mixed function monooxygenase enzymes, CYP1A and CYP2C, have been implicated in synthesizing embryotoxic compounds; therefore, downregulation in the endometrium may be necessary during maternal recognition of pregnancy. 相似文献
123.
OBJECTIVE: This study assessed the impact of changes in school food policy on student lunch consumption in middle schools. METHODS: Two years of lunch food records were collected from students at three middle schools in the Houston, Texas area. During the first year, no changes occurred in the school food environment. After that school year was completed, chips and dessert foods were removed from the snack bars of all schools by the Food Service Director. Students recorded the amount and source of food and beverage items consumed. Point-of-service purchase machines provided a day-by-day electronic data file with food and beverage purchases from the snack bars during the 2-year period. Independent t-tests and time series analyses were used to document the impact of the policy change on consumption and sales data between the two years. RESULTS: In general, student consumption of sweetened beverages declined and milk, calcium, vitamin A, saturated fat and sodium increased after the policy change. Snack chips consumption from the snack bar declined in year 2; however, consumption of snack chips and candy from vending increased and the number of vending machines in study schools doubled during the study period. Ice cream sales increased significantly in year 2. CONCLUSIONS: Policy changes on foods sold in schools can result in changes in student consumption from the targeted environments. However, if all environments do not make similar changes, compensation may occur. 相似文献
124.
Yoo S Baranowski T Missaghian M Baranowski J Cullen K Fisher JO Watson K Zakeri IF Nicklas T 《Public health nutrition》2006,9(3):384-393
OBJECTIVES: To identify the most common frequency of food-purchasing patterns and relate this pattern to characteristics of individuals and families.DESIGN: A customer-intercept survey was conducted in the greater Houston area, Texas, USA, in 2002. The frequency of food shopping at supermarkets, convenience stores and restaurants to buy food for eating at home was assessed.SUBJECTS: A total of 823 adults (78.5% female; mean age 37.4 years) who went to any of several grocery or convenience stores, including European, Hispanic and African Americans, and Asian/Pacific Islanders.RESULTS: Major food-shopping patterns were a weekly big trip with a few small trips (34.9%), biweekly big trips with a few small trips (21.9%), no big shopping trips (15.4%), a weekly big trip without small trips (13.9%), a monthly big trip (8.3%), and biweekly big trips without small trips (6.4%). While 61.1% of participants never went to convenience stores to buy fruit and vegetables (F&V) for eating at home, 67% went to restaurants for F&V. African American families shopped for food least frequently, while Asian American families shopped for food most frequently. Educational level was negatively associated with the use of convenience stores and positively associated with take-away from restaurants.CONCLUSIONS: There is substantial variability in the frequency of food shopping. Future research on food shopping should incorporate this variable. 相似文献
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Development and application of an ELISA for detecting antibodies to Salmonella enteritidis in chicken flocks. 总被引:6,自引:0,他引:6
Enzyme-linked immunosorbent assays (ELISAs) were developed for the detection of IgG antibody to Salmonella enteritidis in poultry flocks. A lipopolysaccharide (LPS) and heat-extracted (HE) antigen for use in the ELISA were evaluated together with the rapid slide test (RST), microagglutination test (MT) and the microantiglobulin (MAG) test. In experimentally infected specific pathogen free chickens, good correlation was seen between all tests although, generally, the MT and MAG detected antibody earlier and titres peaked earlier than the ELISAs. The LPS antigen detected antibody earlier than the HE antigen but the latter gave higher titres in the later stages of infection. Cross reactions were seen between S enteritidis and S typhimurium in the ELISAs although homologous reactions were always much higher. Antisera to S montevideo or S senftenberg gave weak positive reactions in both S enteritidis ELISAs. Serological and bacteriological examinations of representative samples from two commercial chicken flocks were carried out. In flock A the HE-ELISA and MAG test detected antibody in nearly all birds. The LPS-ELISA detected antibody in over 60 per cent of birds, while the MT and RST detected few seropositive birds. The whole blood test using the stained S pullorum antigen on the farm detected antibody in just under 25 per cent of the birds. S enteritidis was isolated from the organs of 25 per cent of the birds. All birds in flock B were seronegative by all tests; no salmonellae were isolated from the organs of these birds. 相似文献
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Boyd PW Jickells T Law CS Blain S Boyle EA Buesseler KO Coale KH Cullen JJ de Baar HJ Follows M Harvey M Lancelot C Levasseur M Owens NP Pollard R Rivkin RB Sarmiento J Schoemann V Smetacek V Takeda S Tsuda A Turner S Watson AJ 《Science (New York, N.Y.)》2007,315(5812):612-617
Since the mid-1980s, our understanding of nutrient limitation of oceanic primary production has radically changed. Mesoscale iron addition experiments (FeAXs) have unequivocally shown that iron supply limits production in one-third of the world ocean, where surface macronutrient concentrations are perennially high. The findings of these 12 FeAXs also reveal that iron supply exerts controls on the dynamics of plankton blooms, which in turn affect the biogeochemical cycles of carbon, nitrogen, silicon, and sulfur and ultimately influence the Earth climate system. However, extrapolation of the key results of FeAXs to regional and seasonal scales in some cases is limited because of differing modes of iron supply in FeAXs and in the modern and paleo-oceans. New research directions include quantification of the coupling of oceanic iron and carbon biogeochemistry. 相似文献