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Background

Gastroesophageal reflux (GER) is common in anesthetized dogs and can cause esophagitis, esophageal stricture, and aspiration pneumonia.

Objective

To determine whether preanesthetic IV administration of esomeprazole alone or esomeprazole and cisapride increases esophageal pH and decreases the frequency of GER in anesthetized dogs using combined multichannel impedance and pH monitoring.

Animals

Sixty‐one healthy dogs undergoing elective orthopedic surgery procedures.

Methods

Prospective, randomized, placebo‐controlled study. Dogs were randomized to receive IV saline (0.9% NaCl), esomeprazole (1 mg/kg) alone, or a combination of esomeprazole (1 mg/kg) and cisapride (1 mg/kg) 12–18 hours and 1–1.5 hours before anesthetic induction. An esophageal pH/impedance probe was utilized to measure esophageal pH and detect GER.

Results

Eight of 21 dogs in the placebo group (38.1%), 8 of 22 dogs in the esomeprazole group (36%), and 2 of 18 dogs in the combined esomeprazole and cisapride group (11%) had ≥1 episode of GER on impedance testing during anesthesia (< .05). Esomeprazole was associated with a significant increase in gastric and esophageal pH (= .001), but the drug did not significantly decrease the frequency of GER (= .955). Concurrent administration of cisapride was associated with a significant decrease in the number of reflux events (RE) compared to the placebo and esomeprazole groups (< .05).

Conclusions and Clinical Relevance

Preanesthetic administration of cisapride and esomeprazole decreases the number of RE in anesthetized dogs, but administration of esomeprazole alone was associated with nonacid and weakly acidic reflux in all but 1 dog.  相似文献   
54.
Characterization of fecundity genes offers the opportunity to improve production efficiency, and the consequent increase in litter size in livestock industry, through utilizing them in breeding programs. The main objective of this study was to detect the BMPR‐IB, BMP15 and GDF9 gene mutations and to investigate whether these mutations are associated with litter size in Egyptian sheep breeds. To achieve this goal, 73 adult ewes representing Barki (n = 33) and Rahmani (n = 40) breeds were used. Polymerase chain reaction–restriction fragment length polymorphism (PCR‐RFLP) screening approach was used to detect the presence of FecB, FecXG and FecXI mutations in the two selected breeds. Results of this study showed that the three different candidate gene mutations, namely FecB, FecXG and FecXI are not present among these selected populations of the Egyptian breeds. Further studies regarding other mutations and/or other genes, which may influence ovulation rate, should be carried out to determine the type and mode of inheritance of such genes in Egyptian sheep breeds.  相似文献   
55.
OBJECTIVE: To determine matrix metalloproteinase (MMP) activity in synovial fluid (SF) obtained from the joints of dogs with degenerative joint disease (DJD) secondary to various underlying conditions. SAMPLE POPULATION: 35 samples of SF obtained from 18 clinically normal (control) dogs and 34 samples of SF obtained from 17 dogs with DJD; dogs with DJD were from 2 populations (client-owned dogs and research dogs that had DJD secondary to the lysosomal storage disease mucopolysaccharidosis VII). PROCEDURE: MMP activity in samples of SF was semiquantitatively examined by use of gelatin or casein zymography. Western blot analysis was performed by use of antibodies for MMP-2 and MMP-9. In addition, in situ MMP activity was observed in sections of synovial membrane obtained from healthy and osteoarthritic joints. RESULTS: Samples of SF from osteoarthritic joints had higher MMP-2 activity and dramatically increased MMP-9 activity, compared with values for healthy joints. Substrate-overlay analyses indicated minimal gelatin-degrading activity in synoviocytes obtained from control dogs, whereas greater activity was seen in osteoarthritic synoviocytes, with additional activity in the underlying tissue. CONCLUSIONS AND CLINICAL RELEVANCE: Higher MMP-2 activity and dramatic increases in MMP-9 activity were associated with the osteoarthritic state, even though MMP-2 activity was detected in healthy joints. This study expands information on MMP production in SF of osteoarthritic joints in other species and documents the similarity of MMP activity patterns regardless of the cause of DJD.  相似文献   
56.
The objective of this study was to investigate (i) the effect of two different ovum pick-up (OPU) schemes (once vs twice weekly aspirations) on oocyte recovery rate, quality and subsequent in vitro embryo development, (ii) the influence of days post-partum on oocyte recovery and (iii) possible differences in OPU results from two different herds. In group A, OPU was performed twice weekly in two Holstein Friesian (HF) and three Danish Red and White (DRW) cows from a private herd. In the research herd, two groups of eight HF cows were investigated: group B (OPU once weekly) and group C (OPU twice weekly). The collected oocytes were subsequently submitted to in vitro embryo production. More oocytes were recovered from the private herd when compared with the research herd. In the research herd, the twice weekly scheme aspirated more oocytes than the once weekly scheme. The quality of the retrieved oocytes was significantly different between groups B and C but not between groups A and C, and HF cows yielded higher quality oocytes than DRW cows (p = 0.029). Oocytes from group C showed higher level of embryonic development than group B oocytes. No differences in blastocyst rates were observed between groups A and C. Session affected the number of retrieved oocytes and subsequent developmental rates, with these being lower in the first compared with the last sessions. Finally, there was no significant effect of days post-partum in the number and quality of the retrieved oocytes, likely because of the small group size and high variation between sessions.  相似文献   
57.
The purpose of this study was to validate a technique for simultaneous evaluation of the plasma, acrosomal and mitochondrial membranes in boar spermatozoa, using an association of fluorescent probes: Propidium iodide (PI), fluorescein isothiocyanate-conjugated Pisum sativum agglutinin (FITC-PSA) and JC-1. Three ejaculates from each of four different boars, all showing motility >or=80% and abnormal morphology 相似文献   
58.
Soon after ovulation, the newly formed corpus luteum (CL) starts secreting progesterone (P(4)), necessary for implantation. The CL, an ovarian transient endocrine organ, undergoes growth and regression throughout its life span. The objective of this study was to evaluate if caspase-3 mediates cell death in the equine cyclic luteal structures and relate it to luteal endocrine function. Blood and luteal tissue were collected during the breeding season after slaughter from 38 randomly assigned cycling mares. Luteal tissues were classified as corpora haemorrhagica (CH; n = 7); mid luteal phase corpora lutea (Mid-CL; n = 17); late or regressing corpora lutea (Late-CL; n = 9) and corpora albicans (CA; n = 5). Plasma P(4) concentration, determined by radioimmunoassay, showed a significant increase from CH to Mid-CL (p < 0.001), followed by a decrease to Late-CL (p < 0.001) and CA (p < 0.001). Caspase-3 processing and poly (ADP) ribose polymerase (PARP) degradation were assessed by western blotting. Active caspase-3 was twofold increased in Mid-CL, Late-CL and CA as compared with CH (p < 0.05). Immunocytochemistry also showed a significant increase in caspase-3 expression in large luteal cells in all structures when compared with CH (p < 0.05). Consistently, the endogenous caspase-3 substrate, PARP, was markedly degraded from CH to CA (p < 0.05). In fact, the ratio of full-length to degraded PARP showed a significant decrease from CH to Mid-CL, Late-CL and CA (p < 0.05). Finally, the decrease in P(4) from Mid- to Late-CL coincided with no further increases in apoptosis. In conclusion, these results suggest that the effector caspase-3 of apoptosis, might play an important role during luteal tissue involution in the mare, even though its relationship with P(4) remains to be elucidated.  相似文献   
59.
Many scientists have expended efforts to determine what regulates development of an indifferent gonad into either a testis or ovary. Expression of Sry and upregulation of Sox9 are factors that initiate formation of the testis-specific pathway to allow for both sex-specific vasculature and seminiferous cord formation. Migration of mesonephric precursors of peritubular myoid cells and endothelial cells into the differentiating testis is a critical step in formation of both of these structures. Furthermore, these events appear to be initiated downstream from Sry expression. Sertoli cell secretion of growth factors acts to attract these mesonephric cells. One hypothesis is that a growth factor specific for these cell linages act in concert to coordinate migration of both peritubular and endothelial cells. A second hypothesis is that several growth factors stimulate migration and differentiation of mesonephric 'stem-like' cells to result in migration and differentiation into several different cell lineages. While the specific mechanism is unclear, several growth factors have been implicated in the initiation of mesonephric cell migration. This review will focus on the proposed mechanisms of a growth factor, Vascular Endothelial Growth Factor, and how different angiogenic and inhibitory isoforms from this single gene may aid in development of testis-specific vascular development.  相似文献   
60.
The role of melatonin as a protective neurohormone against restoring cyclicity in summer anoestrous animals in photoperiod species has gained wider acceptance. This study was designed to uncover the evidence the slow‐release melatonin (MLT) has on initiation of ovarian cyclicity and conception rate (CR) in summer anoestrous buffaloes. Thus, buffaloes diagnosed as summer anoestrous (absence of overt signs of oestrus, concurrent rectal examination and radioimmunoassay for serum progesterone at 10 days interval) were grouped as untreated (Group I, sterilized corn oil, n = 8) and treated (Group II, single subcutaneous injection of MLT @18 mg/50 kg bwt in sterilized corn oil, n = 20). Animals treated and detected in oestrus were artificially inseminated (AI) followed by division into Group III (second dose of MLT on 5th day post‐AI, n = 8) and Group IV (no melatonin administration, n = 10). Blood samples were collected at 4 days interval for estimation of serum MLT, progesterone and oestrogen using radioimmunoassay kit. Mean oestrous induction rate (OIR), oestrous induction interval (OII), interoestrous interval (IOI) and CR were estimated. Compared to control, concentration of melatonin was significantly (p < 0.05) higher in treated group ranging from 14.34 ± 1.72 to 412.31 ± 14.47 pg/ml whereas other two hormones did not show any concentration difference. Melatonin‐administered buffaloes showed significantly (p < 0.05) higher (90%) OIR with OII of 18.06 ± 1.57 days. Results showed improvement in conception rate in buffaloes administered with post‐insemination melatonin. It can be concluded from the study that slow‐release melatonin supplementation restored cyclicity in summer anoestrous animals resulting in improvement in conception rate in buffaloes.  相似文献   
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