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51.
Alteration in hematology and cell-mediated immunity around peripartum periods before and after micronutrient supplementation was studied in this investigation. Twelve (12) high-yielding cross-bred cows in advanced pregnancy were selected for the experiment and divided into two equal groups viz. supplemented (n = 6) and unsupplemented (n = 6). Supplemented animals were provided with a micronutrient mixture (@ 25 g per cow) as per the recommendation of NRC over the normal feeding. Unsupplemented group of cows were kept as control with standard farm feeding management. Blood samples (15 ml/cow) were collected from all the animals during days 30th, 15th, and 7th before calving, on the day of calving, and during days 7th, 15th, and 30th after calving and analyzed for hematology viz. hemoglobin (Hb), total erythrocyte counts (TEC), total leukocyte counts, and differential leukocyte counts. In vitro phagocytic index (PI) of neutrophils and lymphocyte proliferation response (LPR) were also evaluated. Copper (Cu), zinc (Zn), manganese, and selenium (Se) concentrations in serum were estimated by atomic absorption spectrophotometer. The Hb concentration was found to be significantly (p < 0.01) higher in supplemented group compared to the unsupplemented group of cows. There were no significant differences in Hb concentration during different days of peripartum in both the group of cows. There was a significantly (p < 0.001) higher TEC in supplemented group compared to unsupplemented group of cows, though it did not vary significantly between different days of peripartum in both the group of cows. There was a significantly (p < 0.001) higher PI in supplemented group compared to the unsupplemented group of cows. In both the groups, the PI of blood neutrophils was significantly (p < 0.001) lower during calving. The LPR did not differ significantly between the groups, but it differed significantly (p < 0.01) between different days of peripartum and was lowest on the day of calving in both the groups. The Cu, Zn, and SE concentration was found to be significantly (p < 0.01) higher in supplemented group compared to the unsupplemented group of cows, but remained unaltered throughout the peripartum period. The study indicated that there was a marked immune depression around peripartum (15 days precalving to 15 days postcalving) in terms of in vitro phagocytic activity of blood neutrophils and in vitro LPR. Supplementation of micronutrients improves the hematological status as well as immune status, so it was recommended to supplement these micronutrients for better productivity and disease resistance in high-yielding cross-bred cows around peripartum.  相似文献   
52.
Some 19 buffaloes were synchronized by administration of a prostaglandin (PG) salt Lutalyse, with a single intramuscular (i.m.) injection of 25 mg at day -13. Luteolysis was induced by administration of 50 mg PG, in divided doses of 30 and 20 mg i.m. 12 h apart on day 0 of experiment. The 30 mg PG injection was designated as 0 h of experiment. Group I animals (n = 6) received saline and served as controls while animals in Groups II (n = 7) and III (n = 6) received 2500 I.U. PMSG (eCG) i.m. at day -2. Group III animals were administered 5 ml Neutra-eCG intravenously at 60 h. The number of follicles, classified on the basis of diameter as small (2-5 mm), medium (6-9 mm) and large (> or = 10 mm) was assessed by ultrasonography on days -2, -1, 0, 1, 2, 5 and 7 of experiment. The number of corpora lutea (CL) was recorded by palpation per rectum on day 8. The number of small follicles which did not differ among the three groups on days 0, 1 and 2 was significantly lower (P < 0.05) in Group II animals compared to those in Groups I and III on days 5 and 7. The number of medium follicles increased after eCG treatment and was significantly higher (P < 0.05) in animals of Groups II and III on days 0 and 1, compared to control animals of Group I. It was, however, not different among the three groups on subsequent days of experiment. The number of large follicles which did not differ among the three groups on days -2, 0, 1 and 2 was significantly higher in Groups II (P < 0.01) and III (P < 0.05) animals compared to those of Group I on day 5. On day 7, the number of large follicles was in the order (P < 0.05) Group II > Group III > Group I. The number of CL in Group II animals was significantly higher (P < 0.05) than that in Group I animals but was not different from that of Group III animals. These results suggest that treatment of buffaloes with eCG for superovulation reduces the number of small follicles and increases the number of large follicles 5-7 days after PG treatment. Administration of Neutra-eCG 60 h after PG treatment can partly reverse this trend but has no effect on ovulation rate. The possibility that part of the variability in ovulation rates in this study may have resulted from Neutra-eCG been given prior to or at the LH surge, or from the absence or presence of a dominant follicle at the time of eCG treatment cannot be ruled out.  相似文献   
53.
Journal of Plant Growth Regulation - The present study was done to evaluate the effects of tartaric acid (TA) amendment on physiology of Hordeum vulgare L. seedlings under Cr(VI) stress. Cr(VI) at...  相似文献   
54.
The synthesis of a new lipophilic thioflavin-T analogue (2-[4' -(methylamino)phenyl]benzothiazole, 6) with high affinity for amyloid is reported. Intravenous injection of [(11)C]-labeled 6 in control mice resulted in high brain uptake. Amyloid deposits were imaged with multiphoton microscopy in the brains of living transgenic mice following the systemic injection of unlabeled 6. [(11)C]6 is a promising amyloid imaging agent for Alzheimer's disease.  相似文献   
55.
The possibility of producing interspecies handmade cloned (iHMC) embryos by nuclear transfer from donor cells of cattle, goat and rat using buffalo oocytes as recipient cytoplasts was explored. Zona-free buffalo oocytes were enucleated by protrusion cone-guided bisection with a microblade. After electrofusion with somatic cells, reconstructed oocytes were activated by calcimycin A23187, treated with 6-dimethylaminopurine and were cultured in K-RVCL-50® medium for 8 days. Although the cleavage rate was not significantly different when buffalo, cattle, goat or rat cells were used as donor nuclei (74.6 ± 3.8, 82.8 ± 5.3, 86.0 ± 4.9 and 82.3 ± 3.6%, respectively), the blastocyst rate was significantly higher (P < 0.01) for buffalo (51.4 ± 2.6) than for cattle (3.5 ± 1.0) or the goat (2.2 ± 0.9), whereas none of the embryos crossed the 32-cell stage when rat cells were used. However, the total cell number was similar for buffalo–buffalo (175.0 ± 5.07) and cattle–buffalo embryos (178.0 ± 11.84). Following transfer of 3 buffalo–buffalo embryos each to 6 recipients, 3 were found to be pregnant, though the pregnancies were not carried to full term. These results suggest that interspecies blastocyst stage embryos can be produced by iHMC using buffalo cytoplasts and differentiated somatic cells from cattle and goat and that the source of donor nucleus affects the developmental competence of interspecies embryos.  相似文献   
56.
57.
Cytochrome P450 is a superfamily of membrane-bound hemoprotein that gets involved with the degradation of xenobiotics and internal metabolites. Accumulated body of evidence indicates that phospholipids play a crucial role in determining the enzymatic activity of cytochrome P450 in the microenvironment by modulating its structure during detoxification; however, the structure-function relationship of cytochrome P4501A, a family of enzymes responsible for degrading lipophilic aromatic hydrocarbons, is still not well defined. Inducibility of cytochrome P4501A in cultured catfish hepatocytes in response to carbofuran, a widely used pesticide around the world, was studied earlier in our laboratory. In this present investigation, we observed that treating catfish with carbofuran augmented total phospholipid in the liver. We examined the role of phospholipid on the of cytochrome P4501A-marker enzyme which is known as ethoxyresorufin-O-deethylase (EROD) in the context of structure and function. We purified the carbofuran-induced cytochrome P4501A protein from catfish liver. Subsequently, we examined the enzymatic activity of purified P4501A protein in the presence of phospholipid, and studied how the structure of purified protein was influenced in the phospholipid environment. Membrane phospholipid appeared to accelerate the enzymatic activity of EROD by changing its structural conformation and thus controlling the detoxification of xenobiotics. Our study revealed the missing link of how the cytochrome P450 restores its enzymatic activity by changing its structural conformation in the phospholipid microenvironment.  相似文献   
58.
59.
Despite being successfully used to produce live offspring in many species, somatic cell nuclear transfer (NT) has had a limited applicability due to very low (>1%) live birth rate because of a high incidence of pregnancy failure, which is mainly due to placental dysfunction. Since this may be due to abnormalities in the trophectoderm (TE) cell lineage, TE cells can be a model to understand the placental growth disorders seen after NT. We isolated and characterized buffalo TE cells from blastocysts produced by in vitro fertilization (TE-IVF) and Hand-made cloning (TE-HMC), and compared their growth characteristics and gene expression, and developed a feeder-free culture system for their long-term culture. The TE-IVF cells were then used as donor cells to produce HMC embryos following which their developmental competence, quality, epigenetic status and gene expression were compared with those of HMC embryos produced using fetal or adult fibroblasts as donor cells. We found that although TE-HMC and TE-IVF cells have a similar capability to grow in culture, significant differences exist in gene expression levels between them and between IVF and HMC embryos from which they are derived, which may have a role in the placental abnormalities associated with NT pregnancies. Although TE cells can be used as donor cells for producing HMC blastocysts, their developmental competence and quality is lower than that of blastocysts produced from fetal or adult fibroblasts. The epigenetic status and expression level of many important genes is different in HMC blastocysts produced using TE cells or fetal or adult fibroblasts or those produced by IVF.  相似文献   
60.
Digitalis purpurea L. (Scrophulariaceae; Foxglove) is a source of cardiotonic glycosides such as digitoxin and digoxin which are commercially applied in the treatment to strengthen cardiac diffusion and to regulate heart rhythm. This investigation deals with in vitro propagation and elicited production of cardiotonic glycosides digitoxin and digoxin in shoot cultures of D. purpurea L. In vitro germinated seedlings were used as a primary source of explants. Multiple shoot formation was achieved for three explant types (nodal, internodal, and leaf) cultured on Murashige and Skoog (MS) medium with several treatments of cytokinins (6-benzyladenine—BA; kinetin—Kin; and thidiazuron—TDZ) and auxins (indole-3-acetic acid—IAA; α-naphthaleneacetic acid—NAA; and 2,4-dichlorophenoxy acetic acid—2,4-D). Maximum multiple shoots (12.7?±?0.6) were produced from nodal explants on MS?+?7.5 μM BA. Shoots were rooted in vitro on MS containing 15 μM IAA. Rooted plantlets were successfully acclimatized. To further maintain the multiple shoot induction, mother tissue was cut into four equal parts and repeatedly sub-cultured on fresh shoot induction liquid medium after each harvest. On adaptation of this strategy, an average of 18 shoots per explant could be produced. This strategy was applied for the production of biomass and glycosides digitoxin and digoxin in shoot cultures on MS medium supplemented with 7.5 μM BA and several treatments with plant growth regulators, incubation period, abiotic (salicylic acid, mannitol, sorbitol, PEG-6000, NaCl, and KCl), biotic (Aspergillus niger, Helminthosporium sp., Alternaria sp., chitin, and yeast extract) elicitors, and precursors (progesterone, cholesterol, and squalene). The treatment of KCl, mycelial mass of Helminthosporium sp., and progesterone were highly effective for the production of cardenolides. In the presence of progesterone (200 to 300 mg/l), digitoxin and digoxin accumulation was enhanced by 9.1- and 11.9-folds respectively.  相似文献   
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