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Isolde Saalbach Isabel Mora-Ramírez Nicola Weichert Franka Andersch Georgia Guild Herbert Wieser Peter Koehler James Stangoulis Jochen Kumlehn Winfriede Weschke Hans Weber 《Journal of Cereal Science》2014
Optimising assimilate partitioning to spikes is important to increase wheat yield potential. Novel winter wheat lines (HOSUT), ectopically expressing barley sucrose transporter HvSUT1 controlled by the barley Hordein B1 promoter were used to evaluate the potential of improved sucrose uptake capacity on grain yield and quality under field-like conditions. Three independent HOSUT lines were grown over three years in micro-plots. Grain yield per plot was significantly increased by 28%, together with higher protein yield per plot and higher iron and zinc concentration when compared to the non-transformed control wheat Certo. Thousand grain weight was enhanced, indicating that expression of HvSUT1 increases individual grain sink strength. HOSUT grains are larger, display increased grain width and to a lesser extent grain length, indicating transgene effects at a stage when grains grow under filial control. Grain number per spike was decreased by 15% and protein contents by 5%, on average, especially that of glutenins. Overall, despite some compensating effects on grain number per spike and protein contents, HOSUT lines generate a significant yield advantage. The findings can contribute to understanding determinants of grain size and number and its relationship to grain sink strength and might identify limitations of wheat yield potential. 相似文献
684.
A. Calonnec S. Wiedemann‐Merdinoglu L. Delière P. Cartolaro C. Schneider F. Delmotte 《Plant pathology》2013,62(3):533-544
This study was designed to assess the reliability of grapevine leaf bioassays for predicting disease resistance on fruit in the field. The efficacy of various grapevine quantitative trait loci (QTLs) for conferring resistance to downy and powdery mildew was evaluated in bioassays and in a 2‐year field experiment for downy mildew. The resistance genes studied were inherited from Muscadinia rotundifolia (Rpv1 and Run1) and from American Vitis species through cv. Regent (QTLRgP and QTLRgD). In bioassays, genotypes carrying Run1 blocked powdery mildew development at early stages. Genotypes combining Run1 with QTLRgP displayed no greater level of resistance. For downy mildew, genotypes carrying Rpv1 and/or QTLRgD were more resistant than the susceptible cv. Merlot, and showed a high level of leaf resistance in the field (<10% severity). Disease levels on bunches were much higher than those on leaves, with a high variability between Rpv1 genotypes (1–48%). A Bayesian decision theory framework predicted that an OIV‐452 threshold of 5 in leaf bioassays allowed accurate selection of grapevine genotypes (P = 0·83) with satisfactory disease severity on bunches. Therefore, this study validates that the use of early bioassays on leaves, as currently performed by grapevine breeders, ensures a satisfactory level of resistance to downy mildew of bunches in the field. 相似文献
685.
Schneider M Hildebrandt N Schweigl T Schneider I Hagel KH Neu H 《Journal of veterinary internal medicine / American College of Veterinary Internal Medicine》2001,15(3):222-228
Transvenous embolization of small patent ductus arteriosus (PDA; < or = 4 mm) with a single detachable coil was attempted in 24 dogs (median age 5.7 months, range, 2.6-65.5 months; median body weight 5.5 kg, range, 1.5-30.0 kg). Angiographic imaging of the duct and pressure measurements were made before and after embolization. The minimal ductal diameter was 2.7 +/- 0.7 mm. In all dogs, a single coil was employed regardless of residual shunting. Ten dogs (PDA minimal diameter range, 1.5-2.2 mm) received a 5-mm coil, and 14 dogs (PDA minimal diameter range, 2.9-3.6 mm) received a 8-mm coil. After coil embolization the angiographic shunt grade decreased significantly (n = 20, P < .001). Residual shunts were assessed by angiography 15 minutes after and by Doppler echocardiography 1-3 days and 3 months after the intervention. In the dogs treated with the 5-mm coils the residual shunt rate was low (0%, 10%, and 0% for angiography and Doppler echocardiography at 1-3 days and 3 months, respectively), in contrast to the dogs treated with the 8-mm coils (91%, 79%, and 67% for angiography and Doppler echocardiography at 1-3 days and 3 months, respectively). After 3 months, no residual murmur was found in dogs treated with the 5-mm coils (0/7), in contrast to murmurs in 5 of 12 (42%) dogs treated with the 8-mm coils. Despite incomplete closure in these dogs, volume loading of the left heart decreased in all dogs. Pulmonic or aortic coil embolism did not occur. Analysis of initial results shows that single detachable coil embolization is possible in all dogs with a small PDA (< or = 4 mm), but only very small PDA (< or = 2.5) could be treated effectively, and for the moderate PDA (2.6-4.0 mm) longer coils or multiple coils may be necessary to achieve complete occlusion. 相似文献
686.
H V?lker R Pohlann G Furcht K H?rügel U Hohmann E Schneider 《Archiv fuer experimentelle veterinaermedizin》1978,32(2):181-190
The following results were obtained from studies into the behaviour of blood glucose in 439 piglets: -The first experimental group included 48 piglets exposed to follow-up checks in the first ten days of age. Glucose values prior to the first intake of foremilk were higher than those measured afterwards in ten animals (20.8 per cent). The second experimental group included 391 piglets tested under production conditions, and a result identical to the one above was recorded from 48 animals (12.3 per cent). The conclusion is that rise of blood glucose does not take place in all piglets after the first intake of foremilk. -Blood glucose concentrations were found to go up discontinuously up to the tenth day of age, depending on birth weight and feed intake as well as on glycolytical and gluconeogenetical capacities. -Average glucose values between 50.23 and 67.37 mg/100 ml plasma were recorded from newborn piglets prior to first foremilk intake in four groups differentiated by weights a birth between 800 g and 2,200 g. A relationship was statistically secured between blood glucose concentration and birth weight of newborn piglets. The correlation factor appeared to depend on the weight at birth. 相似文献
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688.
M Oettel D Elsner E Schimke P Teichmann H E Schneider E Schneider 《Archiv fuer experimentelle veterinaermedizin》1974,28(5):783-789
A combination of oestriol and testosterone oenanthate was tried in 14 different indications on 110 dogs and 5 cats of both sexes. Two formulations were used, containing in 1 ml either 0.15 mg oestriol and 2.25 mg testosterone or 1.15 mg of the former and 2.25 mg of the latter. Dosage was 0.2 ml per kg body weight, by i/m injection. The criterion for success was the degree of functional restitution, without taking into account pathological changes, which were generally unaffected. Good or very good results were obtained in hip dysplasia, arthitis and patellar luxation. None of the 50 bitches treated showed signs of oestrus or irregularities in the cycle. The formulation containing the lower drug concentration seemed to give the best therapeutic results. 相似文献
689.
690.
Rátky J Torner H Egerszegi I Schneider F Sarlos P Manabe N Brüssow KP 《The Journal of reproduction and development》2005,51(1):109-115
The aim of the present study was to assess follicular and oocyte development in the same gilts during three phases of their reproductive life [prepuberal gilts (PP; 6.0 months of age), puberal gilts (P; 9.5 months of age) and primiparous sows (S)]. Follicular development was stimulated by the injection of 1,000 IU of equine chorionic gonadotropin (eCG) followed by 500 IU of human chorionic gonadotropin (hCG) 72 h later. Cumulus-oocyte-complexes (COCs) were recovered by endoscopic ovum pick up/aspiration from preovulatory follicles of the left ovary, and the follicular fluid (FF) from the right ovary was collected 34 h after the hCG treatment by endoscopy. Altogether, 19 pigs were used in the PP and P trials and 12 in the S trial. From the left ovaries, 168, 190 and 82 follicles were aspirated and 106, 125 and 42 COCs, respectively, were recovered (recovery rate 61 +/- 27, 63 +/- 21 and 53 +/- 22%, respectively). The mean number of follicles was greater in the P phase than in the PP phase (19.7 +/- 6.8 vs. 15.7 +/- 6.8; p=0.06) and S phases (14.2 +/- 4.0; p<0.05). More uniform oocytes with an expanded cumulus were aspirated in the P and PP phases than in the S phase (90 and 78 vs. 46%; p<0.05). Furthermore, the meiotic configuration in oocytes (T I/M II stage) differed between the three phases (56 and 62 vs. 0%; p<0.05). Progesterone (P4) levels in FF decreased from 590.0 +/- 333.6 (PP) to 249.1 +/- 72.6 (P) and 161.4 +/- 75.2 ng/ml (S) (p<0.05). Estradiol-17beta (E2) levels differed between PP and P gilts and S sows (9.3 +/- 2.9, 21.9 +/- 10.6 and 94.0 +/- 15.9 pg/ml, respectively; p<0.05), and the P4/E2 ratio was 72, 15 and 5, respectively. These results indicate differences in follicular and oocyte development between the reproductive phases investigated. Puberal gilts should preferably be used in IVF and breeding programs. The lower reproductive potential of primiparous sows must be taken into consideration in breeding. Any prediction of lifetime performance based on individual ovarian reactions of prepuberal gilts is unreliable. 相似文献