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801.
The objective of the present study was to evaluate estrus synchronization and conception rate after progesterone releasing intravaginal device (PRID) treatment from the early luteal phase in the presence or absence of estradiol benzoate (EB) in heifers. Heifers (n=11) were assigned randomly to two treatments; insertion of a PRID containing 1.55 g progesterone with a capsule attached including 10 mg EB (P+EB; n=6) and the PRID withdrawn the EB capsule (P-EB; n=5). The PRID was inserted into the vagina on Day 2 of the estrous cycle (Day 0 was the day of ovulation) and was left for 12 days. The proportion of heifers exhibiting standing estrus within 3 days after PRID removal was 83.3% (5/6) for the P+EB group, and 80.0% (4/5) for the P-EB group, respectively. Conception rate by artificial insemination on synchronized estrus was 80.0% (4/5) in the P+EB group, and 100% (4/4) in the P-EB treatment group, respectively. These results suggest that a PRID treatment from 2 days after ovulation for 12 days in the presence or absence of EB has an effect on the synchronization of estrus and produces a beneficial conception rate in heifers.  相似文献   
802.
Twenty-four Holstein cattle scheduled for flank surgery in a standing position were randomly assigned to four groups of six. A 16 G, 120 mm Tuohy needle was inserted into the first interlumbar epidural space and its position was confirmed by the hanging drop technique. After air had been allowed to enter freely for approximately one minute, the epidural needle was slowly inserted 7 to 10 mm deeper to penetrate the epidural fat, and anaesthetic solution containing either 0.05 mg/kg bodyweight xylazine hydrochloride (xylazine), 0.025 mg/kg xylazine, 0.025 mg/kg xylazine and 0.1 mg/kg lidocaine hydrochloride (lidocaine), or 0.2 mg/kg lidocaine alone was administered. Signs of sedation were observed in the three groups treated with xylazine and the number of spinal segments involved in the area of analgesia when the anaesthetic contained xylazine was significantly greater than with 0.2 mg/kg lidocaine alone ( < 0.01). After the treatment with 0-025 mg/kg xylazine and 0.1 mg/kg lidocaine, flank surgery was performed successfully without additional line block or side effects.  相似文献   
803.
To characterize spinal cord effects of needle placement using lumbar puncture myelography technique, lumbar puncture was performed in 5 dogs and computed tomography images of the spinal column were acquired in the transverse plane at the level of the puncture site after contrast injection and both before and after needle removal. The spinal cords were punctured during needle placement and parenchymal contrast enhancement was present in 4 of 5 dogs. Although no dogs exhibited overt neurological abnormalities following computed tomographic imaging, hemorrhage, gliosis and axonal degeneration were confirmed microscopically in all subjects. These results suggest that spinal cord morbidity is induced when lumbar myelography is performed using currently accepted technique.  相似文献   
804.
Reproductive diseases after parturition are a serious problem in dairy cattle. It is important to predict postpartum reproductive diseases early and to develop prophylaxis. The objectives of this study were to demonstrate changes in the peripheral blood concentration of interleukin-6 (IL-6) before parturition, which was mainly produced by T helper 2 type (Th2) cells, and to investigate a correlation between the IL-6 concentration and the occurrence of the postpartum retained placenta, endometritis and/or follicular cyst in dairy cattle. Twenty-seven Holstein-Friesian cows were used for this study. Thirteen had no clinical disease, 8 had retained placenta, 4 were diagnosed with endometritis by vaginal inspection, and 2 were diagnosed with follicular cyst by rectal palpation at 1 and 2 months after parturition. Blood samples were collected 60 days pre- and post-partum. They used for IL-6, progesterone (P(4)) and estradiol-17beta (E(2)) concentration determination. This study showed that the IL-6 concentration prepartum was higher than postpartum. Low levels of IL-6 and P(4) in peripheral blood prepartum tended to affect retained placenta and a high level of IL-6 prepartum tended to affect endometritis. These results indicate that measurement of change in the IL-6 concentration during pregnancy is one useful tool for predicting crisis in postpartum reproductive diseases in dairy cattle.  相似文献   
805.
The effects of whole blood storage time on platelet aggregation and on post-transfusion platelet survival time were assessed in dogs. Citrate phosphate dextrose adenine-1 (CPDA-1) was used as a blood cell preservative. Storage time dependent decay of platelet aggregability was assessed. Platelet aggregation responses to collagen and ADP were maintained for at least 8 hr at room temperature. During blood storage, immunoglobulin became nonspecifically bound to platelets, suggesting the potential for immune destruction of platelets by the mononuclear phagocyte system after transfusion. To assess this assumption, the survival times of infused platelets, which were stored for 0 to 8 hr in whole blood, were measured. Post-transfusion survival of platelets was not affected by these storage times. These results suggest that canine platelets maintain viability when stored at room temperature for up to 8 hr in CPDA-1 treated whole blood intended for transfusion.  相似文献   
806.
Skull size and shape were examined among 14 species of the tree shrews (Tupaia montana, T. picta, T. splendidula, T. mulleri, T. longipes, T. glis, T. javanica, T. minor, T. gracilis, T. dorsalis, T. tana, Dendrogale melanura, D. murina, and Ptilocercus lowii). The bones of face were rostro-caudally longer in T. tana and T. dorsalis, contrasting with T. minor and T. gracilis, D. melanura, D. murina and P. lowii which have smaller facial length ratios. The arbo-terrestrial species (T. longipes and T. glis) were similar to terrestrial species in length ratios of bones of face unlike the other arbo-terrestrial species (T. montana, T. picta, T. splendidula, and T. mulleri). We propose that T. longipes and T. glis have adapted to foraging for termites and ants as have T. tana and T. dorsalis. Additionally small body size in T. javanica may be the result of being isolated in Java. We separated the species into 5 groups from the measurment values of skulls: 1) Terrestrial species; T. tana and T. dorsalis, 2) Arboreal species; T. minor and T. gracilis, 3) Arbo-terrestrial species group 1: T. montana, T. splendidula, T. picta and T. mulleri, and T. javanica, 4) Arbo-terrestrial species group 2: T. glis and T. longipes, 5) Arboreal species of Dendrogale and Ptilocercus. Principal component analysis separated species into 8 clusters as follows: 1) T. tana, 2) T. dorsalis, 3) T. montana, T. splendidula, T. picta and T. mulleri, 4) T. glis and T. longipes, 5) T. javanica, 6) T. minor and T. gracilis, 7) D. melanura and D. murina, and 8) P. lowii. We suggest that these clusters correspond to behavioral strategies and peculiarities observed in foraging, feeding and locomotion in each species.  相似文献   
807.
808.
Ambulatory electrocardiogram (ECG) has been recorded in dogs wearing a jacket to protect a Holter recording system, but the jacket was often damaged by dogs. We compared ECG recorded by a Holter recording system and spontaneous activity measured by an accelerometer in Beagle dogs with or without an Elizabethan collar. There were few significant differences in mean values (per hr) of the heart rate and the amount of spontaneous activity between dogs with or without the Elizabethan collar. Mean values (per 23 hr) of them had no significant difference between them. We concluded that the Elizabethan collar did not have any effect on ambulatory ECG and canine movements and was effective to protect the recording apparatus.  相似文献   
809.
Endocrine cells immunoreactive for somatostatin, gastrin, glicentin, glucagon, secretin, cholecystokinin, motilin and neurotensin were identified immunocytochemically in the gastrointestinal mucosa of the horse. Somatostatin-, glicentin- and glucagon-immunoreactive cells were very numerous in the cardiac and fundic regions of the stomach, whereas most gastrin-immunoreactive cells were confined to the pyloric region. Somatostatin-immunoreactive cells also were detected in all portions of the small intestine while gastrin-immunoreactive cells were confined exclusively to the upper portion and glicentin-immunoreactive cells were limited to the lower portions of the small intestine. Secretin-, cholecystokinin- and motilin-immunoreactive cells were observed only in the duodenum, while neurotensin-immunoreactive cells were confined primarily to the ileum. In the large intestine, somatostatin- and glicentin-immunoreactive cells were detected in the colon and rectum. The preferential location of endocrine cells provides additional information for future studies on the physiological roles of gastrointestinal peptides in the gastrointestinal tract of the horse.  相似文献   
810.
The bovine pregnant corpus luteum was examined morphologically, to clarify the appearance and properties of the intramitochondrial bodies (IMB) in mitochondria of the large luteum cell (LLC). The incidence and diameter of the IMB (200–900 nm) showed a tendency to increase with the advance of pregnancy. Histochemically, the IMB reacted positively with protein, and immunohistochemically, they reacted IMB with 11 α-hydroxyprogesterone-1-11 succinyl-bovine serum albumin (P-BSA). The IMB seemed to combine with protein, and these granules did not undergo exocytosis. The cytoplasm of LLC contained another type of small electron-dense granules that were 150–200 nm in diameter, had an orifice for secretion, and reacted with relaxin. Small luteum cells (SLC) revealed crystalline-like inclusions. It is suggested that these inclusion cells participate in the synthesis of steroids.  相似文献   
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