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451.
Naturally occurring radial aplasia was found in 14 of 26 closely related mink examined for forelimb abnormalities. The condition resembles human radial aplasia. Attempts to determine genetic or other causes were unsuccessful 相似文献
452.
453.
John T. Hathcock DVM MS Ram C. Purohit BVSc & AH PHD Jan E. Bartels DVM MS Gerald H. Hankes DVM PHD Shei-Wen Lee DVM MS Luisito S. Pablo DVM MS 《Veterinary radiology & ultrasound》1989,30(5):227-231
Carotid arteriography was performed in six normal goats. The same procedure was performed on these six and 112 other goats at various time intervals after placement of an arterial graft in one or both carotid arteries. An arterial catheter was introduced into the femoral artery and advanced to the origin of the brachiocephalic trunk with the aid of image-intensified fluoroscopy. Hand-injection of the contrast medium resulted in complete opacification of both common carotid arteries in normal animals. Opacification of one or both of the vertebral arteries was usually seen in the goats with prosthetic grafts. The left vertebral artery was seen more often than the right, and when both vertebral arteries were seen together, the left was often larger. This angiographic method proved to be reliable for opacifying both common carotid arteries from their origin on the brachiocephalic trunk to the cranial cervical region. No clinical problems were associated with either the catheterization procedure or with the permanent ligation of the catheterized femoral artery. 相似文献
454.
Resistance and cross-resistance to insecticides in human head lice from Florida and California 总被引:1,自引:0,他引:1
Kyong Sup Yoon Jian-Rong Gao Si Hyeock Lee Gerald C. Coles Terri L. Meinking David Taplin John D. Edman MiwaKo Takano-Lee J. Marshall Clark 《Pesticide biochemistry and physiology》2004,80(3):192-201
Head lice from Florida (SF-HL) and California (SC-HL) were resistant to permethrin compared with colonized susceptible lice from Panama (PA-HL) (5.5- and 3.4-fold, respectively) and Ecuador (EC-HL) (8.5- and 5.3-fold, respectively). Permethrin-resistant lice were cross-resistant to pyrethrum and DDT. DNA sequencing validated presence of kdr-type mutations (T929I and L932F). Permethrin resistance was synergized by piperonyl butoxide (PBO) in SC-HL. Resistance to malathion in SF-HL (1.4–2.2-fold) and SC-HL (2.1–3.6-fold) was detected. Malathion resistance in SF-HL was synergized by S,S,S-tributylphosphorotrithioate (DEF) and by PBO in SC-HL. Malathion/permethrin-resistant lice from the UK (BR-HL) were synergized by DEF but not synerziged by PBO. PBO protected BR-HL from malathion, indicating suppressed desulfuration. Abamectin resistance in SF-HL (1.7–2.5-fold) and SC-HL (1.8–2.3-fold) was detected. No resistance to lindane was found. Thus, multiple resistance mechanisms against commonly available and widely used pediculicides and insecticides are apparently occurring. 相似文献
455.
Borjesson DL Christopher MM Ling GV 《Veterinary clinical pathology / American Society for Veterinary Clinical Pathology》1999,28(1):33-38
Canine transitional cell carcinoma (TCC) carries a poor prognosis in part due to late disease detection. The measurement of specific tumor markers shed in the urine may aid in sensitive, early disease detection and therefore improved prognosis. A 1-year prospective clinical trial was designed to assess the efficacy, sensitivity and specificity of the first generation Bard BTA test to diagnose TCC in dogs. This test is a qualitative, rapid, latex agglutination, dipstick test run on voided urine, which measures a glycoprotein antigen complex associated with bladder cancer in human patients. Sixty-five dogs were entered in the study: 20 TCC confirmed patients, 19 healthy controls and 26 urologic controls with a variety of conditions including urinary tract infection, crystalluria and proteinuria. Overall test sensitivity was 90% and specificity was 78%. False positive test results were noted in the presence of significant glucosuria (4+), proteinuria (4+), and pyuria or hematuria (> 30-40 WBC or RBC per hpf). Urine parameters that had no effect on efficacy included collection method (cystocentesis or free catch), pH, specific gravity, crystalluria, bilirubinuria, bacteriuria and casts. These data indicated that the Bard BTA test was sensitive for the detection of the bladder tumor-associated antigen complex in canine TCC. As evaluated, this test may serve as a useful adjunct to diagnosis, especially when cytology or biopsy is questionable or impractical. Furthermore, because of the high sensitivity of the test, it may be a practical screening test to rule out TCC in geriatric patients or patients with clinical signs related to the lower urinary tract, particularly before pyuria and hematuria develop which may interfere with test results. 相似文献
456.
John G. Brayan Paul R. Haddad Gerald J. Sharp Sergio Dilli James M. Desmarchelier 《Pest management science》1992,34(3):215-219
Carbaryl was extracted from aged samples of rice, maize, peas and sunflower seeds using hexane, acetone and methanol. The quantities of insecticide extracted from the grain by acetone and methanol were much higher than that extracted by hexane for all four products. Methanol extracted higher levels of carbaryl than acetone from maize and peas but for rice and sunflower seeds the results were similar for the two solvents. Extraction by simply standing the whole grain in solvent for 48 h generally resulted in similar extracted levels of carbaryl to those obtained using more exhaustive techniques, such as grinding the grain or Soxhlet extraction. However, grinding or Soxhlet extraction removed the pesticide from the grain more rapidly. 相似文献
457.
458.
Boll weevils, Anthonomus grandis Boheman, were either dipped in or injected with a solution of [14C]diflubenzuron (N-[[(4-chlorophenyl)amino]carbonyl]-2,6-difluorobenzamide) or fed on cotton squares that had been treated with the chemical to determine its turnover time and metabolic fate. No significant differences were observed between male and female weevils in their ability to eliminate [14C]diflubenzuron. Only minor differences were observed when immersion and injection treatments were compared. When weevils were treated with 66.3 ng of [14C]deflubenzuron per weevil by injection, the insects contained 13 to 15% of the radiolabel after 6 days and 4 to 6% after 13 days. The remainder of the radiolabel was in the frass. When weevils fed for 66 hr on cotton squares that had been treated with a wettable [14C]diflubenzuron preparation (Dimilin W-25), the insects averaged 120 ng of diflubenzuron per weevil. Forty-four hours after removing insects from the treated squares, 50% of the radiolabel had been excreted. In all cases, the radiolabel found in the frass or in the weevil was unchanged diflubenzuron. There were no data to indicate that the boll weevil could metabolize appreciable amounts of diflubenzuron. 相似文献
459.
460.
Effect of cultural practices and fungicides on Phytophthora fruit rot of watermelon in the Carolinas 总被引:1,自引:0,他引:1
Chandrasekar S. Kousik Mike L. AdamsWilfred R. Jester Richard HassellHoward F. Harrison Gerald J. Holmes 《Crop Protection》2011,30(7):888-894
Phytophthora fruit rot of watermelon, caused by Phytophthora capsici, is an important and emerging disease in Southeastern U.S.A. The effects of two cultural practices (raised bare ground and raised plastic mulched beds) used for growing watermelon and different fungicide treatments on development of Phytophthora fruit rot were evaluated. The experiments were conducted over three years (2005-2008) at research stations in North Carolina and South Carolina, U.S.A. Fungicides were applied at weekly intervals on the diploid cv. Mickey Lee for an average of five applications. Fruit rot incidence was recorded at the end of each experiment. Fruit rot incidence in the non-treated plots was 66% across two states and six trials. Overall, the levels of fruit rot on the raised bare ground and raised plastic mulched beds were not significantly different. Based on percent disease reduction relative to the non-treated check plots, the fungicide Captan was the most effective across years and locations (range = 23-70%, mean = 57%), followed by mandipropamid (25-65%, mean = 50%), fluopicolide (24-65%, mean = 43%) and cyazofamid (0-48%, mean = 31%). Mefenoxam, the current standard treatment reduced fruit rot by 8-28% (mean = 18%). The addition of copper hydroxide to the spray mix did not significantly enhance effectiveness of Captan or mandipropamid. The variability in fungicide efficacy observed in these experiments across locations and years demonstrates the importance of environmental conditions in disease development and management. Even when the most effective fungicides are used, heavy losses may occur when conditions are highly favorable for disease development. Ultimately, effective control of Phytophthora fruit rot of watermelon will require an integrated management strategy that includes well-drained fields, water management and crop rotation in addition to fungicides. 相似文献