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951.
952.
Ivermectin was evaluated for anthelmintic activity in calves naturally infected with gastrointestinal helminths. Five of 10 calves were treated subcutaneously with ivermectin at 200 micrograms per kg body weight. One-hundred percent efficacy was indicated against adult and immature Haemonchus, Trichostrongylus, Bunostomum phlebotomum and Oesophagostomum radiatum. Adult Cooperia were also completely eliminated, and a 95.5% reduction was obtained for the immature forms; an 88.7% reduction was obtained for Trichuris spp. 相似文献
953.
954.
955.
Relationship between the serum concentrations of serotonin and lipids and aggression in dogs 总被引:1,自引:0,他引:1
The serum concentrations of serotonin and lipids--triglycerides, total cholesterol, low density lipoprotein, high density lipoprotein and very low density lipoprotein--were determined in 18 normal dogs and 23 dogs diagnosed as aggressive on the basis of interviews with their owners and an assessment of their behaviour with reference to a canine overt aggression chart. The serum serotonin levels in the aggressive dogs were significantly lower than in the normal dogs (P<0.01), but the differences in serum lipids between the two groups were not statistically significant. 相似文献
956.
Kridli RT Momany Shaker M Abdullah AY Muwalla MM 《Tropical animal health and production》2007,39(3):229-235
This study was conducted to evaluate the sexual performance of 10-month-old, ram lambs of different breed groups. Eight ram
lambs each of Awassi (A), F1 Charollais × Awassi (CA) and F1 Romanov × Awassi (RA) breed types were subjected to sexual performance tests by being individually exposed to two oestrous
Awassi ewe lambs for four 20-min periods. Bouts of leg kicking and anogenital sniffing were similar among breed groups. Mounting
frequency was greater (p < 0.05) in RA than in A and CA ram lambs. Tail-raising was greater (p < 0.05) and mating rate tended to be greater (p < 0.10) in A than in RA and CA ram lambs. The number of mounts per tail-raising (efficiency) was influenced by breed group
and test day (p < 0.05). Awassi ram lambs maintained the best efficiency throughout the experiment. Efficiency in RA and CA ram lambs improved
with each test day. Results of the present study indicate that RA ram lambs have greater mounting frequency than A and CA,
while Awassi are more capable of mating with fat-tailed females than the CA and RA ram lambs. 相似文献
957.
An Economic Opportunity Survey was conducted on dairy farms in the North West Province of Cameroon. Results showed that median
(range) number of cows in milk per farm was zero point six (0–4) and six (3–12) in the zero grazing and transhumance systems,
respectively. Medians (range) of three (0–24) and four (3–10) litres of milk were sold per farm per day, corresponding to
30% and 60% of milk produced. 24% and 13% of total cattle per herd were milking cows in the zero grazing and transhumance
systems respectively. Median milk production per cow on one day was two (0–25) and two (1–3) litres. Median calf production
interval was 14.5 (12–25) and. 21.5 (14–29) months. More milk produced per day represented the best economic opportunity in
both systems while reduced age at first calving and longer lactation length were the next in both. Wastage of milk through
spoilage from poor hygiene and lack of cooling was a major problem. Holstein cows, which were in the zero grazing system,
had unexpectedly short lactations. Constraints identified led to the setting up of interventions of training and advice for
farmers and of better nutrition. 相似文献
958.
959.
960.
Rhoades RD Sawyer JE Chung KY Schell ML Lunt DK Smith SB 《Journal of animal science》2007,85(7):1719-1726
Angus (n = 8; 210 kg of BW) and 7/8 Wagyu (n = 8; 174 kg of BW) steers were used to evaluate the effects of dietary energy source on muscle and adipose tissue metabolism and insulin sensitivity. Steers were assigned to either a grain-based (corn) or hay-based (hay) diet and fed to similar final BW. At slaughter, LM and s.c. and i.m. adipose tissue samples were collected. Portions of the LM and adipose tissues were placed immediately in liquid N for later measurement of glycolytic intermediates. Fresh LM and s.c. and i.m. adipose tissues were incubated with [U-(14)C]glucose to assess glucose metabolism in vitro. All in vitro measures were in the presence of 0 or 500 ng/mL of insulin. Also, s.c. and i.m. adipose tissues were incubated with [1-(14)C]acetate to quantify lipid synthesis in vitro. Glucose-6-phosphate and fructose-6-phosphate concentrations were 12.6- and 2.4-fold greater in muscle than in s.c. and i.m. adipose tissues, respectively. Diet did not affect acetate incorporation into fatty acids (P = 0.86). Insulin did not increase conversion of glucose to CO(2), lactate, or total lipid in steers fed hay but caused an increase (per cell) of 97 to 110% in glucose conversion to CO(2), 46 to 54% in glucose conversion to lactate, and 65 to 160% in glucose conversion to total lipid content in adipose tissue from steers fed corn. On a per-cell basis, s.c. adipose tissue had 37% greater glucose oxidation than i.m. adipose (P = 0.04) and 290% greater acetate incorporation into fatty acids than i.m. adipose (P = 0.04). Insulin addition to s.c. adipose tissue from corn-fed steers failed to stimulate glucose incorporation into fatty acids, but exposing i.m. adipose tissue from corn-fed steers to insulin resulted in a 165% increase in glucose incorporation into fatty acids. These results suggest that feeding hay limited both glucose supply and tissue capacity to increase glucose utilization in response to insulin without altering acetate conversion to fatty acids. Because s.c. adipose tissue consistently utilized more acetate and oxidized more glucose than did i.m. adipose, these results suggest that hay-based diets may alter i.m. adipose tissue metabolism with less effect on s.c. adipose tissue. 相似文献