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1.
OBJECTIVES: To investigate the prevalence of anaemia and iron deficiency and vitamin A status among school-aged children in rural Kazakhstan and identify factors associated with anaemia in this population. DESIGN: A cross-sectional design. SETTING: School-aged children in rural Kazakhstan. SUBJECTS: Socio-economic and anthropometric information was collected from 159 school-aged children living in the Kzyl-Orda region of Kazakhstan. Blood samples were collected and the concentrations of haemoglobin (Hb), serum iron, serum ferritin (SF), erythrocyte protoporphyrin (EP), serum retinol and beta-carotene, total iron binding capacity (TIBC), transferrin saturation (TS) and other haematological indices were measured. RESULTS: Among the 159 children, the prevalence of anaemia and iron deficiency defined by the multiple criteria model (SF, TS and EP) was 27% and 13%, respectively. Nine per cent had iron-deficiency anaemia and 21% had serum retinol value < 1.05 micromol l(-1). Mean SF and serum iron concentrations and TS were significantly lower in anaemic children than in their non-anaemic peers, while TIBC and EP were significantly higher in children with anaemia. Hb was significantly correlated with serum iron and retinol concentrations. Serum retinol and SF concentrations and mean corpuscular volume were significantly correlated with Hb by multiple regression analysis. CONCLUSIONS: Anaemia among school-aged children in rural Kazakhstan appears to be related to iron indices and vitamin A status.  相似文献   
2.
Dry matter production, net photosynthetic rate, leaf nutrient status and trunk anatomical characteristics of Fagus crenata seedlings grown in brown forest soil acidified by adding H2SO4 solution were investigated. The soil acidification leaded to decreased (Ca+Mg+K)/Al molar ratio in the soil solution. Dry mass per plant of the seedlings grown in the soil treated with H+ at 120 mg·L?1 was significantly reduced compared with the control value at 0 mg·L?1. When net photosynthetic rate was reduced in the seedlings grown in the soil treated with H+ at 120 mg·L?1, the carboxylation efficiency and maximum net photosynthetic rate at saturated CO2-concentration were lower than the control values. The addition of H+ to the soil at 120 mg·L?1iinduced a reduction in the concentration of Ca in the leaf. By contrast, the concentration of Al in the leaf was increased with increasing the amount of H+ added to the soil. The annual ring formed in the seedlings grown in the soil treated with H+ at 120 mg·L?1 was significantly narrower than that at 0 (control), 10, 30, 60 or 90 mg·L?1. Based on the results obtained in the present study, we conclude that Fagus crenata is relatively sensitive to a reduction in the (Ca+Mg+K)/Al molar ratio of soil solution compared with Picea abies.  相似文献   
3.
Inbred mice of the C3H/He (resistant) and C57BL/6 (susceptible) strains and their hybrids were used in experiments to investigate the genetic regulation of host resistance to B. anthracis. The susceptibility of F1 mice to a standard spore suspension was similar to that of the resistant parent and not intermediate between values for the parent strains. There were no differences in mortality rate between F1 and reciprocal cross mice. Analysis of the results indicated that resistance of mice to B. anthracis is regulated by a single dominant gene.  相似文献   
4.
The absorption of atmospheric radionuclides by soybean plants was experimentally studied using a radioactive multitracer consisting of radionuclides of Sc, Mn, Co, As, Se, Rb, Sr, Y, Eu, Gd, Yb, Hf, Re, and Ir. The soybean plants were cultivated in soil under no-rain conditions in a box containing air in which multitracer-absorbed cellulose particles were dispersed. The soil was covered with plastic film. After about one-month cultivation, the plants were harvested and washed with dilute HCl solution. The leaves, stems, and beans were subjected to γ-ray measurement. The radionuclides of As, Se, and Re were accumulated in the leaves, and those of Co, Se, and Rb were accumulated in the beans. Among them Se was accumulated to a large extent in the leaves and in the beans. Small amounts of the radionuclides of Co, Se, Rb and Re were found in the roots. Little absorption of these radionuclides into the soil occurred. These results indicate that various radionuclides in the atmosphere were absorbed through the soybean leaves and then transported to the seeds. These findings must be taken into consideration for a complete understanding of the system of uptake of radionuclides by the soybean plant.  相似文献   
5.
The aim of this study was to investigate whether functional tumor necrosis factor-alpha (TNFalpha) receptors are present in the granulosa cells and the cells of theca interna (theca cells), obtained from bovine follicles classified into one of three groups. Each group was defined as either small vesicular ovarian follicles (small follicles; 3-5 mm in diameter), preovulatory mature ovarian follicles (preovulatory follicles) or atretic follicles (12-18 mm) according to gross examination of the corpus luteum in the epsilateral or contralateral ovary and the uterus (size, color, consistency and mucus), and the ratio of progesterone (P(4)) and estradiol-17beta (E(2)) concentrations in follicular fluid. A Scatchard analysis showed the presence of a high-affinity binding site on both granulosa and theca cells from all follicles examined (dissociation constant: 4.7 +/- 0.15 to 6.9 +/- 1.40 nM). Moreover, TNFalpha receptor concentrations in granulosa and theca cells obtained from atretic follicles were significantly higher than those in the cells from preovulatory follicles (P<0.05). Exposure of cultured granulosa cells from small antral follicles to recombinant human TNFalpha (rhTNFalpha; 0.06-6 nM) inhibited E(2) secretion in a dose-dependent fashion (P<0.01), but did not affect P(4) secretion. In addition, rhTNFalpha inhibited follicle stimulating hormone-, forskolin- or dibutylyl cyclic AMP-induced P(4) and E(2) secretion by the cells (P<0.01). These results indicate the presence of functional TNFalpha receptors in bovine granulosa and theca cells in small, preovulatory and atretic follicles, and suggest that TNFalpha plays a role in regulating their secretory function.  相似文献   
6.
To establish a storage system for isolated endometrial cells, we investigated the basal, oxytocin (OT)- and tumor necrosis factor (TNF) alpha-stimulated production of prostaglandin (PG) F(2alpha) in bovine-passaged and frozen-thawed endometrial cells. Stromal and epithelial cells obtained from cows in the early stage of the estrous cycle (Days 2-5) were frozen at -80 C or further cultured and/or passaged until passage 4 in DMEM/Ham's F-12 supplemented with 10% calf serum. A fresh-unfrozen primary culture and one-time passaged fresh-unfrozen cells were used as the control. When both unfrozen and frozen cells reached confluence, the culture medium was replaced with fresh medium with 0.1% BSA and the cells were stimulated with OT (100 ng/ml) or TNFalpha (1 ng/ml) for 4 h. The passage and freezing of the endometrial cells did not affect their morphology. In primary culture of frozen and unfrozen endometrial cells, OT strongly stimulated PGF(2alpha) production in epithelial cells, and TNFalpha strongly stimulated PGF(2alpha) production in stromal cells (P<0.05). The basal output of PGF(2alpha) in frozen stromal cells was similar to that in unfrozen stromal cells. However, the basal output of PGF(2alpha) in frozen epithelial cells was significantly lower than that unfrozen cells (P<0.05). On the other hand, in passaged cells, the basal level of PGF(2alpha) production was retained until passage 1 in epithelial cells, whereas it was retained until passage 4 in stromal cells. Although epithelial cells responded to OT in PGF(2alpha) production until passage 2 (P<0.05), the stromal cells showed a significant response to TNFalpha until passage 4 (P<0.05). These results suggest that stored cells could be used for studying the physiology of bovine endometrium in vitro until passage 1 in endometrial epithelial cells, and until passage 4 in stromal cells.  相似文献   
7.
Luteinizing hormone (LH)-stimulated steroidogenesis in luteal cells is known to be mediated through the activation of cyclic AMP (cAMP)-dependent protein kinase, and to be also modulated by calcium-dependent mechanisms. In the present study, we tested the hypothesis that LH stimulates progesterone (P4) production in bovine luteal cells through activation of phospholipase (PL) C by using a cell culture system. Bovine mid-luteal cells (Days 8-12 of the estrous cycle) were cultured for 24 h and then exposed to a PLC inhibitor (U-73122; 10 microM) with or without LH (10 ng/ml) for 4 h. U-73122 blocked LH-stimulated P4 production without affecting cAMP accumulation. Moreover, exposure of luteal cells to PLC increased P4 production in a dose-dependent manner. These results support the hypothesis that the luteotropic action of LH in bovine luteal cells is mediated not only by activation of adenylate cyclase but also by activation of PLC.  相似文献   
8.
A fraction containing low-molecular-weight peptides that catalyzes redox reactions between electron donors and O2 to produce ·OH, was partially purified from wood-decaying cultures of the brown-rot fungusTyromyces palustris. Polyclonal antibodies raised to the fraction were used for immunogold labeling of transverse sections of sapwood of spruce in various stages of degradation byT. palustris to demonstrate the cellular localization of the ·OH-producing substance. Initially, the wood cell wall was attacked primarily by fungal hyphae growing in the cell lumen. During the early stages of degradation, the gold label was localized in the fungal cytoplasm and cell wall and in the extracellular slime sheath surrounding the fungal cell wall. The gold label also was found throughout the wood cell wall, although the cell wall remained almost intact so long as the fungal hyphae remained in the lumen. Thus, the ·OH-producing substance is secreted by the hyphae into the lumen, and it diffuses through the S3 layer into the S2 layer and the middle lamella. The role of this ·OH-producing system in wood degradation byT. palustris is discussed.  相似文献   
9.
10.
Gustatory neural responses of the Pacific bluefin tuna Thunnus orientalis (Temminck and Schlegel) to extracted compounds of prey organisms, such as amino acids, nucleotide‐related substances, organic acids and organic bases, were electrophysiologically recorded from the facial nerve supplying the anterior palate. Of the 17 amino acids tested, l ‐proline was the most potent amino acid at 10?2 M, and its threshold was the lowest at around 10?6 M. l ‐leucine, l ‐methionine, l ‐alanine, l ‐valine and l ‐isoleucine were also highly stimulatory at 10?2 M; however, the other 11 amino acids examined were not as effective or were ineffective. Thus, the gustatory receptors for amino acids of the Pacific bluefin tuna show a narrowly tuned response profile. Among the seven nucleotide‐related substances tested, uridine‐5′‐monophosphate, inosine‐5′‐monophosphate and adenosine‐5′‐diphosphate were highly stimulatory, and their thresholds were 10?4–10?5 M. Inosine elicited a positive response at 10?2 M but its response magnitude was not so high. Organic acids l ‐lactic and pyruvic acids were effective at 10?2 M, but no response was elicited at 10?3 M. Among organic bases, betaine was highly stimulatory, and its response magnitude at 10?2 M is almost equal to that of l ‐proline at the same concentration. The threshold for betaine was determined to be at around 10?5 M. Trimethylamine oxide and ammonium chloride were ineffective.  相似文献   
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