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81.
82.
CASE HISTORY A 5-day-old red deer calf was submitted with tachypnoea and dyspnoea, and was reluctant to move.

CLINICAL FINDINGS: Muscular damage was established via elevated creatinine phosphokinase (CPK) activities (5,000 U/L), while concentrations of Se in whole blood were low (24.8 nmol/L). The animal died despite treatment with penicillin-streptomycin and 0.1 mg/kg Se/vitamin E administered by S/C injection.

DIAGNOSIS: Necropsy and histological examination of cardiac and skeletal muscle confirmed the presumptive diagnosis of congenital white muscle disease (WMD). Prophylactic administration of a Se/vitamin E commercial preparation (as above) to another calf born in the same herd one month later was associated with good health and apparently normal growth and development.

CLINICAL RELEVANCE: Congenital WMD due to Se deficiency can be fatal in red deer calves. However, prophylactic administration of Se and vitamin E to neonatal calves may be beneficial for neonatal red deer calves.  相似文献   
83.
Abstract

AIM: To monitor the consequences of withdrawing mineral Cu supplements from two dairy herds with initially high concentrations of Cu in liver.

METHODS: Two herds were selected from dairy farms in the Waikato region of New Zealand that participated in an earlier survey of Cu supplementation practices and Cu status of dairy cows. The herds were fed pasture, grass and maize silage, plus palm kernel expeller (PKE) containing 25–30 mg Cu/kg dry matter (DM) fed at 2–4 kg/cow/day. No mineral Cu supplements were supplied from January 2009. Pasture samples were collected for mineral analysis in September 2008 and April 2009. Concentration of Cu in liver biopsies from the same 9–10 cows per herd was measured on three occasions between April 2009 and May 2010.

RESULTS: Pastures on both farms contained 10 mg Cu/kg DM, 0.1–0.5 mg Mo/kg DM and 3.5–4.0 g S/kg DM. The initial herd mean concentrations of Cu in liver were 1,500 (SD 590) and 1,250 (SD 640) μmol Cu/kg fresh tissue. In the absence of mineral Cu supplements, those mean concentrations decreased over 12 months to 705 (SD 370) and 1,120 (SD 560) μmol Cu/kg fresh tissue, respectively. For cows in the first herd, the rate of depletion of liver Cu reserves was influenced by initial concentration of Cu, such that high concentration led to faster loss according to first-order kinetics.

CONCLUSIONS: Mineral Cu supplementation was not necessary over 12 months for two dairy herds with mean concentrations of Cu in liver >1,250 μmol Cu/kg fresh tissue, grazing pastures containing 10 mg Cu/kg DM and concentrations of Mo <1 mg/kg DM. The quantity and particularly the duration of feeding PKE appeared to be a factor in whether or not the herd lost substantial reserves of Cu in liver during the year. However, the Cu status of both herds in this study was more than adequate to support late pregnancy and mating.

CLINICAL REVELANCE: Copper status of the herd should be monitored and on-farm management of Cu nutrition should take into account all sources contributing to daily intake of Cu. Where Cu supplementation has been excessive and there is risk of chronic Cu toxicity, mineral Cu supplements may be withdrawn for a period commensurate with the expected rate of liver Cu depletion.  相似文献   
84.
AIM: To investigate growth responses of cobalt-deficient lambs to increasing doses of microencapsulated vitamin B12, and to measure associated changes in serum and liver vitamin B12 concentrations over 243 days.

METHODS: From a flock grazing pastures that had low cobalt (Co) levels (about 0.06 mg Co/kg dry matter), 4-6-week-old lambs (n=137) were assigned to four groups and received either no treatment or a subcutaneous injection of 3.0, 4.5 or 6.0 mg of microencapsulated vitamin B12 on Day 1. At approximately monthly intervals, all lambs were weighed and blood samples were collected from a selection (n=10) of monitor animals, up to Day 243. Liver biopsies were also carried out on the monitor lambs (n=8) on Days 1, 124 and 215.

RESULTS: The vitamin B12-treated lambs grew significantly faster (p<0.001) than untreated animals. Liveweights after 243 days were 28, 45, 45 and 47 kg for the untreated, 3.0, 4.5 and 6.0 mg vitamin B12-treated lambs, respectively. Of the initial group of untreated lambs, 68% had to be removed before the end of the trial because of substantial weight loss, but none of the treated animals were similarly afflicted. Serum vitamin B12 concentrations increased in all vitamin B12-treated lambs, reaching a peak at Day 25, and those of the 4.5 and 6.0 mg vitamin B12-treated lambs remained significantly higher (except at Day 124) than the untreated lambs to Day 187. However, at Day 124, but not Day 215, the liver vitamin B12 concentrations of treated lambs were two to three times higher than those of controls.

CONCLUSIONS: The growth rates of Co-deficient lambs were markedly improved by injection of 3.0, 4.5 or 6.0 mg of microencapsulated vitamin B12, and liveweights were maintained for at least 243 days. Serum vitamin B12 concentrations were related to this growth response; concentrations of <220 pmol vitamin B12/l were associated with a 95% probability that lambs were Co-deficient and would thus respond to Co/vitamin B12 supplementation. Based on these data, the current New Zealand reference criteria for Co deficiency should be reviewed.

CLINICAL SIGNIFICANCE: An injection of 3 mg microencapsulated vitamin B122 given to lambs at tailing will treat Co deficiency and will increase and maintain liveweights in a flock for up to 8 months.  相似文献   
85.
Melia dubia, a multipurpose tree species, is gaining importance to meet the demand supply gap of timber, plywood and pulpwood . In June 2016, a serious outbreak of wilt disease was observed in M. dubia seedlings planted in the Central Nursery of Forest Research Institute (FRI), Dehradun, India. The disease led to the destruction of one hundred thousand (100,000) seedlings. Earlier in June 2012, serious wilting of M. dubia seedlings was observed in Haryana, India. The pathogen was identified as Fusarium solani following standard laboratory procedures and sequence analysis of the internal transcribed spacer (ITS) region of the ribosomal DNA (rDNA). The pathogenicity of three isolates has been proved under greenhouse conditions. This is the first report of F. solani causing wilt of M. dubia.  相似文献   
86.
87.

Background

ABT‐751 is a novel orally available antimitotic agent that targets microtubule polymerization. This mechanism may suggest potential activity in canine lymphoma.

Objective

Determine a maximum tolerated dose for ABT‐751, and assess long‐term tolerability and activity in canine lymphoma.

Animals

Thirty dogs with newly diagnosed (n = 19) or relapsed (n = 11) non‐Hodgkin's lymphoma.

Methods

Dogs (n = 11) were enrolled in a rapid dose escalation study to define the maximum tolerated dose. Upon definition of a maximally tolerated dose, a cohort expansion of 19 dogs allowed verification of long‐term tolerability and assessment of activity. Study endpoints in the cohort expansion included chronic tolerability, response rate, response duration, and time to progression. Additional endpoints included serum pharmacokinetics, lymph node drug concentrations, and changes in circulating endothelial cells.

Results

The maximum tolerated dose of ABT‐751 was 350 mg/m2 PO q24h. Dose‐limiting toxicities included vomiting and diarrhea, which resolved with a schedule adjustment to 350 mg/m2 PO q48h. ABT‐751 was consistently detected in lymphoma tissue samples from dogs treated at or above the maximum tolerated dose. In the cohort expansion, objective responses were seen in 3/15 (20%) dogs with a response duration ranging from 21 to 111 days. Decreases in circulating endothelial cells were seen in 10 dogs at day 7 (2 responding dogs and 8 nonresponding dogs).

Conclusion

ABT‐751 was well tolerated at 350   mg/m2 PO q24h for 7 days and then q48h thereafter. Activity of ABT‐751 suggested a rationale for additional studies of ABT‐751 as part of a combination chemotherapy protocol for lymphoma or other canine cancers.  相似文献   
88.
89.
This study was designed to investigate the sensitivity and specificity of three methods for detecting the onset of cyclicity in post-partum Murrah buffaloes. The methods investigated were visual signs, transrectal ultrasonography, and serum progesterone (P4) assay. For this study, 102 post-partum Murrah buffalo cows were grouped for monitoring their ovarian activity. The first group of buffaloes was between 26 and 35 days post-partum. Thereafter, the buffalo cows that calved were grouped after every 10 days for the study sample. Thus, the study animals were adjudged between 26 and 35, 36–45, 46–55, 56–65, 66–75, 76–85, and 86–95 days post-partum with an average of 30, 40, 50, 60, 70, 80, and 90 days post-partum, respectively. Visual estrus signs were monitored twice daily, and simultaneously, ultrasound examination was carried out at 10 days interval for accessing the presence of corpus luteum (CL). Serum P4 was estimated in the animals which were adjudged cyclic by ultrasound examination, and the assay was repeated after 10 days. The buffalo cows in estrus were inseminated artificially, and pregnancy status was assessed after 30 days post-insemination. In this study, the sensitivity and specificity of visual observation were low (39.37 and 70.73%, respectively) when compared to P4 assay (98.80 and 96.47%) and ultrasound examination (single, 97.59 and 97.59%; double, 100 and 100%), respectively. Furthermore, the sensitivity and specificity of single and double ultrasound examination and P4 assay were comparable. In conclusion, this study reports that single and double ultrasound examination and P4 assay are more efficient than visual observation in detecting the onset of ovarian cyclicity in post-partum Murrah buffaloes.  相似文献   
90.
BACKGROUND: The dosage of carboplatin in cats has been reported anecdotally and experimentally in non-tumor-bearing cats, but the dosage for carboplatin treatment in tumor-bearing cats has yet to be defined in a prospective clinical trial. PURPOSE: To determine the maximally tolerated dose (MTD) and dose-limiting toxicosis (DLT) of carboplatin in tumor-bearing cats. CATS: Fifty-nine cats with measurable solid tumors. METHODS: The starting dose of carboplatin was 160 mg/m(2) of body surface area IV. Doses were increased by 20 mg/m(2) in cohorts of 3-14 cats until the MTD was reached. RESULTS: The 59 cats entered into this multi-institutional phase I study received 1 or more doses of carboplatin at various dosages and were evaluated for toxicity, response to treatment, or both. The MTD was 240 mg/m(2) and neutropenia was the DLT. For the 1st cycle of treatment in 44 cats evaluated for neutropenia, 6 episodes of grade 3 or greater neutropenia occurred on days 7 (n=1), 14 (n=4), and 21 (n=1). There was no evidence of drug-induced nephrotoxicosis or pulmonary edema. Preliminary evidence of antitumor activity was observed in 7 of 59 (11.9%; 95% CI, 5.6-22.8%) cats evaluated for response to treatment. There was 1 complete response (cutaneous hemangiosarcoma) and 6 partial responses (4 injection site sarcomas, 1 oral squamous cell carcinoma, 1 lymphoma). Responses were of short duration (median, 42 days; range, 7-168 days). CONCLUSIONS AND CLINICAL IMPORTANCE: The dose of carboplatin recommended to treat tumor-bearing cats is 240 mg/m(2) IV every 3-4 weeks.  相似文献   
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