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11.
Sound and sprouted flours (24 and 48 hr) from bread wheat (WL-1562), durum wheat (PBW-34) and triticale (TL-1210) were stored at room temperature (34.8°C) and relative humidity (66.7%) for 0, 45, 90 and 135 days to assess the changes in physico-chemical and baking properties. Protein, gluten, sedimentation value, starch and crude fat decreased during storage in all the samples; however, the decrease was more in sprouted flours. Free amino acids, proteolytic activity, diastatic activity and damaged starch decreased with increase in storage period. Total sugars and free fatty acids increased more rapidly in the flours of sprouted wheats during 135 days of storage. Loaf volume of breads decreased during storage in both sound and sprouted flour but the mean percent decrease in loaf volume was more in stored sound flours. Aging of sprouted flour for 45 days improved the cookie and cake making properties but further storage was of no value for these baked products.Chapati making properties of stored sound and sprouted flour were inferior to that of fresh counterparts.  相似文献   
12.
Leukocytes isolated from intraepithelium, lamina propria, and aggregated lymphatic follicles of the small intestine of healthy adult cattle were tested for their ability to produce interleukin 2 (IL-2) by in vitro stimulation of cells with mitogens. Supernatants from interepithelial leukocytes, lamina propria leukocytes, and cultures stimulated with concanavalin A (conA), phytohemagglutinin, and pokeweed mitogen contained growth factors with the capacity to maintain proliferation of a bovine IL-2-dependent lymphoblastoid cell line. Interleukin-2 activity was demonstrated in supernatants of all 3 conA-stimulated leukocyte populations as early as 20 hours after initiation of culture, reached peak values at 30 to 50 hours, and decreased by 72 hours. Although quantitative variations of IL-2 production were observed between various cell types and among cattle, conA was the most potent in inducing IL-2 activity in all 3 leukocyte populations. Supplementation of culture medium with 2-mercaptoethanol or phorbol myristrate acetate neither induced IL-2 production nor enhanced mitogen-induced IL-2 production. Addition of indomethacin to conA-stimulated cultures enhanced IL-2 production. Although depletion of adherent cells did not affect IL-2 production, total elimination of Ia-positive accessory cells inhibited its production by all 3 cell populations. Lymphocytes responsible for IL-2 production in aggregated lymphatic follicle population were presumptive T cells because they were nylon wool-nonadherent, B26A positive (monoclonal antibody directed against pan T cells), pIg45A negative (antibody directed against pan B cells), and considered peanut agglutination-positive.  相似文献   
13.
The surface phenotypes of bovine intestinal leukocytes isolated from the intraepithelium (IEL), lamina propria (LPL) and Peyer's patches (PPL) of the small intestinal mucosa of normal adult cows were determined using monoclonal antibodies (mAb) specific to adult bovine peripheral blood leukocytes (PBL). Laser flow cytometric (LFC) analysis demonstrated that IEL contained significantly (P less than 0.1 to 0.02) fewer cells (26%) expressing the pan T cell phenotype in comparison to LPL (38%) and PPL (44%). Similarly, significantly (P less than 0.01 to 0.001) lower numbers of B cells were observed among IEL (10%) compared to LPL (28%) and PPL (33%). While approximately equal numbers of B7A1+ "null" cells (10%) and DH59B+ "Ia+ monocytes/granulocytes" (16.5%) were observed among the three intestinal cell populations, IEL contained significantly (P less than 0.1 to 0.05) lower numbers (19%) of T helper (Th) cells in comparison to LPL (44%) and PPL (38%). In contrast, lymphocytes with the T cytotoxic/suppressor (Tc/s) phenotype were significantly lower (P less than 0.01 to 0.001) among LPL (14.5%) compared to IEL (25%) and PPL (23%). While the numbers of cells expressing class I major histocompatibility complex (MHC) surface antigens (H58A+) were approximately equal among LPL (79%) and PPL (87%), a significant difference (P less than 0.02) was observed between IEL (71%) and PPL. Similarly, while approximately equal numbers of cells expressing the MHC class II surface phenotype were observed among LPL (42%) and PPL (46%), IEL contained significantly (P less than 0.01) fewer (31%) MHC class II cells in comparison to PPL. Enrichment for T cells by plastic adherence and Sephadex G-10/nylon wool fractionation revealed a significant (P less than 0.01) and proportional increase in T lymphocyte subsets expressing pan T, Th and Tc/s phenotypes among the three cell populations. Similarly, enrichment for B cells by the same techniques showed a significant (P less than 0.01) and proportional increase in cells expressing the panB cell phenotype among LPL and PPL. Marked differences in cell size distribution and cell surface density were observed when the three intestinal leukocyte populations were compared by LFC using monoclonal antibodies directed at various cell surface markers. Furthermore, considerable quantitative variations of each cell surface marker were observed among the individual animals tested. The results of this study indicate that bovine IEL, which contain a high percentage of cells (greater than 30%) with no known phenotype are significantly different from LPL and PPL which are phenotypically similar cell populations.(ABSTRACT TRUNCATED AT 400 WORDS)  相似文献   
14.
In winter, the confined pig house of northern China is severe. The environment variables are nonlinear, time-varying and coupled, which seriously affect the health of pigs and the qualities of the meat. In order to solve the problem multi-variables coupling, a multi-variables decoupled fuzzy logic control method was proposed. Two fuzzy logic controllers were designed based on fuzzy logic theory. The fans, heaters and humidifiers were used to control temperature, humidity and ammonia. The reductions of temperature and humidity caused by ventilating were compensated by heaters and humidifiers respectively which realized the multivariables decoupling. The proposed methods were validated through theoretical, experimental and simulation analysis. The results suggested that the methods were able to regulate the confined pig house environment effectively. In addition, comparing to the manual regulation, the proposed methods could reduce 19% power consumption as well.  相似文献   
15.
The uptake and translocation of 14C-isoproturon (3-p-cumenyl-1-1,-dimethylurea) in wheat (tolerant) and backgrass (sensitive) following foliar treatment under controlled environmental conditions were examined. The amount of 14C-isoproturon translocated through the xylem was about 10 times that translocated through the phloem in both wheat and blackgrass. However, 25.5% of the applied 14C-isoproturon was translocated in the xylem in blackgrass, compared with 8.9% in wheat. 14C-isoproturon did not respond significantly to induced sink-demand in either species. Leaf-disc autoradiograms revealed the absorption of 14C-isoproturon by the minor veins and translocation into the cut vein endings. No significant differences were found in between wheat and blackgrass in this respect.  相似文献   
16.
There are some disadvantages, such as complicated wiring, high cost, poor monitoring flexibility, low accuracy and high energy consumption in traditional greenhouse environment monitoring system which based on previous wireless sensor networks(WSN). Aiming at these problems, a greenhouse environmental parameter monitoring system had been designed based on internet of things technology in this paper. A set of control system with good robustness, strong adaptive ability and small overshoot was set up by combining the fuzzy proportion-integral-derivative(PID) control. The system was composed of a number of independent greenhouse monitoring systems. The server could provide remote monitoring access management services after the collected data were transmitted. The data transmission part of greenhouse was based on Zig Bee networking protocol. And the data were sent to intelligent system via gateway connected to the internet. Compared to the classical PID control and fuzzy control, the fuzzy PID control could quickly and accurately adjust the corresponding parameters to the set target. The overshoot was also relatively small. The simulation results showed that the amount of overshoot was reduced 20% compared with classical PID control.  相似文献   
17.
Leukocytes isolated from the intraepithelium, lamina propria, and aggregated lymphoid follicles (ALF) of the bovine small intestinal mucosa were activated by concanavalin A (conA) to generate suppressor activity against the proliferative response of autologous and allogeneic leukocytes to conA, phytohemagglutinin, and pokeweed mitogen. Freshly obtained intraepithelium, lamina propria, and ALF leukocytes, preincubated with 25 to 50 micrograms/ml of conA for 24 to 48 hours, were able to inhibit the mitogenic responses of autologous and allogeneic lymphocytes when cocultured at a ratio greater than or equal to 1:1 (suppressor cells to responder cells). Depletion of adherent cells (monocytes/macrophages) by sequential plastic and gel adherence completely abrogated the conA-induced suppressor activity of all 3 leukocytes populations. However, reconstitution with autologous or allogeneic monocytes/macrophages during the induction phase restored the inducible suppressor activity. Addition of recombinant human interleukin-2 at a concentration as low as 5 U/ml during the responder phase enabled the responder population to recover the response apparently impaired by the conA-treated ALF leukocytes. At a concentration of 10 U/ml, human interleukin-2 was not only able to restore the responder population's response to phytohemagglutinin stimulation, but highly enhanced its proliferative ability. Although quantitative variations were observed between different cell populations and cells obtained from individual cows, the extent and general pattern of the inducible suppressor activity were similar in cells from cows studied.  相似文献   
18.
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