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1.
This study aimed to investigate the major salivary glands in the southern white-breasted hedgehog (Erinaceus concolor) histologically and histochemically. Five adult males were included in this study. The results showed that anatomically the shape of the parotid, submandibular and sublingual glands of the Erinaceus concolor was respectively almost pear, elliptical to pyramidal and oval. Histologically, the parotid gland had serous acini and secretory cells showed negative reaction to alcian blue (AB) (pH = 2.5) and negative response to aldehyde fuchsin (AF), methylene blue (MB) and PAS stains. The submandibular gland was a mixed gland of mucous and serous acini. The mucous acini were strongly positive for PAS, AB, MB and AF. However, serous acini were week for PAS and negative against AB, MB and AF stains. The sublingual gland was purely composed of mucous acini. The mucous acini of the sublingual gland were strongly positives for PAS, AB and MB methods. While their reaction to the AF staining was negative. In conclusion, the histological and histochemical observations of the major salivary glands of the southern white-breasted hedgehog (E. concolor) indicated that these glands shown similarities and some special different histochemical features as compared to other mammalian species.  相似文献   
2.
A laboratory experiment was conducted to investigate the relative mobility of dicyandiamide (DCD) and jointly applied ammoniacal salts or urea in three different soils of lower Egypt, and to determine the extent to which DCD separates from N-fertilizer in unsaturated soil undergoing leaching. The experimental results suggest that, under conditions of water flow, DCD is readily separated from NH4+ but parts from urea to a far lesser extent. The large difference in mobility between DCD and NH4+ should severely limit the effectiveness of DCD as a nitrification inhibitor in the three soils considered when applied in conjunction with ammoniacal salts. In two out of three cases, the situation is similarly unfavorable in the case of joint DCD and urea application. However, the observation that DCD, in a low CEC sandy loam, moves within the soil solution at a slightly lower rate than urea suggests that joint application with urea would keep at least part of the DCD in contact with the NH4+ ions and, therefore, would preserve some of the effectiveness of DCD under leaching conditions in this soil.  相似文献   
3.
Isocupressic acid (1) was used to synthetically prepare a mixture of (8S,13R,S)-labda-15,19-dioic acid (tetrahydroagathic acid) (5) via a two-step oxidation procedure followed by hydrogenation of the double bonds at C13 and C8. Reduction of the C8,17 double bond was stereospecific producing only the 8S isomer and confirmed by the nOe interaction between the resulting C17 and C20 methyl groups. The 13R and 13S isomers of 5 were separated and analyzed by HPLC/MS, and (13S)-tetrahydroagathic acid was isolated and identified by comparison to a standard prepared by hydrogenation of naturally occurring (13S)-dihydroagathic acid (4). (13R,S)-dihydroagathic acid was prepared by selective sodium metal-catalyzed hydrogenation of the C13,14 allylic double bond of agathic acid (3). The prepared compounds were then used as standards to confirm the presence of 4 and 5 and their respective 13R and 13S isomers in bovine serum samples. Tetrahydroagathic acid was shown to be the only metabolite detected in serum samples taken from a suspected cattle abortion case submitted for diagnosis; and, thus, 5 could be a valuable diagnostic marker for pine needle-induced abortions.  相似文献   
4.
Background: One of the limitations in the treatment of common diseases such as cancer chemotherapy is development of multidrug resistance (MDR). Polymorphisms could alter the expression level of MDR1 gene, which plays an important role in MDR. In this research, the frequency of C3435T, C1236T, and G2677T/A polymorphisms of MDR1 gene was investigated in a large group of population from Hamadan city to provide a sample data resource. Methods: Peripheral blood (2 ml) was taken, and DNA extraction was carried out. Multiplexed mutagenically separated PCR, which was followed by polyacrylamide gel electrophoresis and silver staining, was applied to detect the mentioned polymorphisms in 935 individuals. Sequencing performed for confirmation of gel electrophoresis resulted in 10 random cases. In total, alleles and genotypes of 933 persons (776 women and 157 men) were determined. Results: The most frequent alleles of the polymorphisms were: 3435T, C1236, and G2677. The most frequent genotypes were: 3435C/T, 1236C/T, and 2677G/A, and their concurrent presence was also found as the most frequent simultaneous genotypes. There was not any meaningful difference among the prevalence of these genotypes in groups of men and women. Conclusion: Our results were close to those of other studies performed in Iran and compared to the other ethnic groups, which showed more similarity to Asian peoples than Europeans. As an aspect of personalized medicine, it could be used by chemotherapists to improve the routine methods of cancer treatment.Key Words: Gene polymorphism, Multi-drug resistance, Neoplasm  相似文献   
5.
6.
The consumption of ponderosa pine (Pinus ponderosa), lodgepole pine (Pinus contorta), common juniper (Juniperus communis), and Monterey cypress (Cupressus macrocarpa) causes abortions in pregnant cattle. Recent studies have identified isocupressic acid (1) as the primary abortificient compound in these plants. In vitro and in vivo studies using rumen and blood have shown isocupressic acid (1) is rapidly metabolized to agathic acid (3), dihydroagathic acid (4), and tetrahydroagathic acid (5). Rapid and sensitive diagnostic techniques are needed to identify poisoned animals, to study toxicokinetics, and to elucidate the mechanism of isocupressic acid-induced abortion in cattle. In this study, four competitive inhibition enzyme-linked immunosorbent assays for isocupressic acid and its sera metabolites were developed using polyclonal antibodies. One assay is specific to 1, whereas the other three assays show cross-reactivity to 3-5 in addition to 1. The assay specific to 1 had a limit of detection of 44.1 pg. The other assays which demonstrated cross-reactivity to the isocupressic acid blood metabolites also had comparably low limits of detection. One assay was used to follow the absorption and elimination profile of isocupressic acid metabolites in both cow serum and urine after oral dosage of a cow with common juniper.  相似文献   
7.
In recent years Lake Mariut was subjected to severe pollution. The phosphate content of this Lake was exceedingly higher than that of the other Egyptian Lakes. The distribution of phosphates in Lake Mariut was found to depend upon certain factors which were discussed.  相似文献   
8.
Seeds of lettuce, variety Romaine were subjected to different priming treatments such as water, potassium nitrate (KNO3) and gibberellic acid (GA3). Seedlings obtained from primed (Pr) and nonprimed (NP) seeds were grown in a hydroponic culture system supplemented with 0, 100 or 200 mM sodium chloride (NaCl). The different physiological and biochemical responses were studied 15 days after treatment. Under NaCl, the dry weight was higher in plants derived from hydro-primed (HP) seeds when compared to NP, osmoprimed (KNO3P), and hormonal primed (GA3P) ones. Under control and 100 mM NaCl treatment, malondialdehyde (MDA) content and EL did not show any correlation with activities of gaiacol peroxidase (GPX) and catalase (CAT), but did with the increase in reduced ascorbate (AsA) and total ascorbate contents. The results indicated that plants derived from HP seeds exhibited higher adaptive potential under salinity stress. Our findings suggest that a hydropriming technique can be used as a simple commercial approach to alleviate the effects of NaCl induced stress in lettuce plants.  相似文献   
9.
Introduction: Although extensive research has been conducted on lung cancer markers, a singular clinically applicable marker has not been found yet. The objective of this study was to evaluate the sensitivity and the specificity of carcinoembryonic antigen (CEA) mRNA and lung-specific X protein (LUNX) mRNA biomarkers in peripheral blood to detect lung cancer individually and simultaneously. Methods: Thirty patients affected by lung cancer and 30 healthy individuals were studied in this research. Three vials of cDNA were made from each sample after taking peripheral blood samples and extracting total RNA. Each sample was examined by the real-time RT-PCR technique. The result from each vial was then compared with the sensitivity of overall marker. Results: The CEA mRNA was positive in 24 out of 30 lung cancer patients. Hence, its sensitivity was determined at 80%, differing significantly from that observed in healthy individuals, where 11 positive cases were seen. The overall sensitivity of this marker was significantly associated with positivity in vials 2 and 3 but not in vial 1. The LUNX mRNA was positive in 21 out of 30 patients, indicating 70% sensitivity. This finding significantly differed from that in healthy individuals. The overall sensitivity of this marker was significantly associated with positivity in vials 1 and 3, but not in vial 2. In 93.3% of the patients, at least one positive marker was observed. Conclusion: The mentioned mRNA could be suggested as sensitive and specific markers in peripheral blood for primary diagnosis of lung cancer.Key Words: Lung neoplasms, RNA, Carcinoembryonic antigen, Sensitivity and specificity  相似文献   
10.
The present investigation aims to study the potential protective role of exogenous applications of gibberellin, auxin, citric acid and calcium on the growth and cellular redox state of pea (Pisum sativum L.) germinating seeds exposed to copper stress. All tested treatments alleviated the adverse effects of Cu-induced toxicity on the growth, cell viability and mobilization of nutrients from the cotyledons. This alleviation of Cu toxicity occurred by limiting heavy metal biosorption and maintaining cellular redox homeostasis. Redox balance, examined through the study of the redox state of nicotinamide couples NAD+/NADH and NADP+/NADPH appeared to be protected by the treatments. This correction was correlated to a modulation of NAD(P)H-oxidase and dehydrogenase activities, such as glucose-6-phosphate dehydrogenase, 6-phosphogluconate dehydrogenase and malate dehydrogenase. The present research provides evidence that supplementation of plants with gibberellin, auxin, citric acid and calcium was an effective approach for enhancing Cu tolerance in pea seedlings.  相似文献   
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