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61.
Due to the increased attention that pet‐owners devote to their animals and to the improved veterinary care, investigations regarding methods to early detect prostatic disorders that might affect canine life quality have been performed. Canine prostate specific esterase (CPSE) concentration was reported to be higher in dogs suffering from prostatic diseases. This study aimed to estimate the CPSE threshold as a biomarker to early identify prostatic diseases in asymptomatic dogs. The ultrasonographic examination of the prostate was performed in 19 dogs (6–40 kg; 1–5 years) with no symptoms of prostatic diseases. Dogs were grouped according to the presence (Group A) or absence (Group B) of prostatic disorders at the ultrasound (altered appearance, the presence of cysts or irregular borders). For each dog, a venous blood sample was collected to measure serum CPSE and the ratio between calculated and normal expected prostatic volume was assessed for each dog. The CPSE data were statistically analysed (t test, p < .05), and the CPSE threshold in blood serum between groups was calculated by ROC. In 11 dogs, ultrasonography showed signs of prostatic abnormalities (Group A, 2–5 years), while no signs were detected in eight dogs (Group B, 1–3 years). The calculated/estimated volume ratio resulted greater than 1.5 in Group A dogs. The CPSE was statistically different between groups (p < .0001): higher in Group A (mean = 184.9, SD = 126 ng/ml) than in Group B (38.9 ± 22.1 ng/ml). The cut‐off CPSE threshold was 52.3 ng/ml (ROC, AUC = 0.974, SE 95.6%, SP 89.2%). This study suggests that CPSE serum concentration higher than 50 ng/ml in asymptomatic dogs is associated with ultrasonographic alterations and increased the prostatic size (volume by 1.5 times greater than the normal size). As the onset of prostatic disorders often remains asymptomatic, the rapid assessment of CPSE could be suitable for selecting preventively those animals that would require further accurate evaluation.  相似文献   
62.
This study evaluated colour‐Doppler ultrasound imaging (UI) as a substitute for laparoscopy to count the corpora lutea (CL) in superovulated sheep. Twenty‐five Santa Ines ewes were superovulated three times at 21‐day intervals. Corpora lutea were counted by colour‐Doppler UI (CLDOPPLER) 6 days after each superovulation and confirmed by laparoscopy (CLLAP) 12 hr later. The mean number of CL was similar for both techniques (2.1 ± 2.5 vs. 2.1 ± 2.7 for CLDOPPLER and CLLAP, respectively) with a significant positive correlation (r = .94; r2=.89). Colour‐Doppler UI effectively evaluated the ovarian response in superovulated ewes and efficiently identified animals that did not respond to superovulation.  相似文献   
63.
BMP‐6 has been found to be important to ovarian cells and oocyte, as well as to uterus. Thus, this study investigated the effect of bone morphogenetic protein (BMP‐6) and recombinant follicle‐stimulating hormone (rFSH) alone or in combination on the in vitro culture (IVC) of isolated caprine secondary follicles (Experiment 1) and the mRNA levels for BMP receptors/Smad signalling pathway (BMPR1A, BMPR2, SMAD1, SMAD4, SMAD5, SMAD6, SMAD7 and SMAD8) in vivo and in vitro using BMP‐6 (Experiment 2). Secondary follicles were cultured in αMEM+ alone (control medium) or supplemented with BMP‐6 at 1 or 10 ng/ml and rFSH alone or the combination of both BMP‐6 concentrations and rFSH. The results from Experiment 1 showed that the antrum formation rate was higher in the BMP‐6 at 1 ng/ml (p < 0.05) than in MEM. In Experiment 2, the mRNA expression for BMPR2, SMAD1, SMAD5 and SMAD6 was detected in non‐cultured control and after in vitro culture (MEM and 1 ng/ml BMP‐6); while the expression of SMAD7 and SMAD8 mRNA was only detected after IVC, SMAD4 was only detected in the BMP‐6 at 1 ng/ml treatment. In conclusion, the low BMP‐6 concentration positively influenced antrum formation and ensured normal mRNA expression for BMP receptor and Smads after IVC of caprine secondary follicles.  相似文献   
64.
OBJECTIVE: To determine the cause of an epidemic of blindness in kangaroos. DESIGN AND PROCEDURES: Laboratory examinations were made of eyes and brains of a large number of kangaroos using serological, virological, histopathological, electron microscopical, immunohistochemical methods, and PCR with cDNA sequencing. In addition, potential insect viral vectors identified during the disease outbreak were examined for specific viral genomic sequences. SAMPLE POPULATION: For histopathological analysis, 55 apparently blind and 18 apparently normal wild kangaroos and wallabies were obtained from New South Wales, Victoria, South Australia, and Western Australia. A total of 437 wild kangaroos and wallabies (including 23 animals with apparent blindness) were examined serologically. RESULTS: Orbiviruses of the Wallal and Warrego serogroups were isolated from kangaroos affected with blindness in a major epidemic in south-eastern Australia in 1994 and 1995 and extending to Western Australia in 1995/96. Histopathological examinations showed severe degeneration and inflammation in the eyes, and mild inflammation in the brains. In affected retinas, Wallal virus antigen was detected by immunohistochemical analysis and orbiviruses were seen in electron microscopy. There was serological variation in the newly isolated Wallal virus from archival Wallal virus that had been isolated in northern Australia. There were also variations of up to 20% in genotype sequence from the reference archival virus. Polymerase chain reactions showed that Wallal virus was present during the epidemic in three species of midges, Culicoides austropalpalis, C dycei and C marksi. Wallal virus nucleic acid was also detected by PCR in a paraffin-embedded retina taken from a blind kangaroo in 1975. CONCLUSION: Wallal virus and perhaps also Warrego virus are the cause of the outbreak of blindness in kangaroos. Other viruses may also be involved, but the evidence in this paper indicates a variant of Wallal virus, an orbivirus transmitted by midges, has the strongest aetiological association, and immunohistochemical analysis implicates it as the most damaging factor in the affected eyes.  相似文献   
65.
Two concepts for use in the fabrication of three-dimensional (3D) microstructures with complex topologies are described. Both routes begin with a two-dimensional (2D) pattern and transform it into a 3D microstructure. The concepts are illustrated by use of soft lithographic techniques to transfer 2D patterns to cylindrical (pseudo-3D) substrates. Subsequent steps-application of uniaxial strain, connection of patterns on intersecting surfaces-transform these patterns into free-standing, 3D, noncylindrically symmetrical microstructures. Microelectrodeposition provides an additive method that strengthens thin metal designs produced by patterning, welds nonconnected structures, and enables the high-strain deformations required in one method to be carried out successfully.  相似文献   
66.
Ultrasound is one of the most promising forms of non‐invasive contraception and has been studied in several animal models. The objective of the current investigation was to determine the most practical and effective application protocol for dog sterilization. A total of 100 dogs were divided into five equal groups. Group A received 5‐min applications three times performed at 48‐hr intervals and covering the entire testicular area at frequency of 1 MHz; Group B received 5‐min applications three times performed at 48‐hr intervals over the dorso‐cranial area of the testis at frequency of 3 MHz; Group C received three sequential 5‐min applications (at 5‐min intervals between applications) covering the entire testicular area at frequency of 1 MHz; Group D received 15‐min applications two times performed at 48‐hr intervals and covering the entire testicular area at frequency of 1 MHz. The experimental groups' ultrasound had an intensity of 1.5W/cm2. The Control Group had the same procedure as Group A, but with the transducer switched‐off. Dogs were surgically castrated 40 days following the treatment for histological examination. Azoospermia, testicular volume reduction and apparently irreversible testicular damage were achieved by Group A. No effects were noticed in the other groups. Testosterone levels remained within physiological range with all application protocols. A regimen of three applications of ultrasound at 1 MHz, and 1.5 W/cm2, lasting 5 min with an interval of 48 h was effective as permanent sterilization in the dog without hormonal impact.  相似文献   
67.
68.
This study aimed to establish a culture system that improves the in vitro development of caprine preantral follicles. In a first experiment, follicles were encapsulated as a single unit per bead and cultured singly or in groups or with five follicles in the same alginate (ALG) bead for 18 days. In a subsequent experiment, the “five follicles per bead” design was chosen to culture in ALG, fibrin–alginate (FA) or hyaluronate (HA) for 18 days. In a third experiment, we chose the five follicles per bead in FA to culture for 30 days. The culture set‐up of five follicles per ALG bead increased antrum formation and follicle diameter compared to the other culture designs (p < .05). Moreover, under this condition, 44.44% of the oocytes from in vitro cultured preantral follicles reached meiotic resumption. A significant increase of follicle diameter occurred in attachment system and FA (p < .05), but the ALG condition reached the highest among all groups on day 18 (p < .05). Follicles encapsulated in matrix produced more estradiol and progesterone than attachment system (p < .05). The expression of MMP‐9 mRNA was higher in FA than in other groups (p < .05) and similar to antral follicles from in vivo control (p > .05). Only FA group resulted in oocytes matured. After 30 days, oocytes from preantral follicles in vitro grown in FA developed to eight‐cell parthenotes. In conclusion, a culture system using FA supported the development of caprine preantral follicles cultured in group and included in the same bead of hydrogel, improving the oocyte maturation and producing parthenotes.  相似文献   
69.
70.
Flocks of broiler breeder chickens housed on a commercial farm were monitored from 13 w of age for natural infection with endemic lentogenic Newcastle disease virus (NDV). Seroconversion was first detected at 17 w. By 24 w, all 8 flocks had achieved peak log2 mean haemagglutination inhibiting antibody titres of up to 4.8. Antibody titres then declined and rose again over several months, suggesting cyclic reinfection with NDV. A lentogenic NDV indistinguishable from V4 was isolated from the cloaca of one bird at 18 weeks of age. At 54 weeks of age, 6 of 8 flocks were vaccinated en masse with live V4 NDV vaccine, 3 flocks by drinking water and 3 flocks by aerosol. All flocks were serologically monitored for a further 8 w. Drinking water vaccination induced an anamnestic response in 3 flocks, showing that flocks with pre-existing active immunity to NDV may be successfully vaccinated with V4. However, in all aerosol vaccinated flocks, the procedures failed to induce a response different to that observed in unvaccinated flocks. The serological response to vaccination was greater in sires than in dams.  相似文献   
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