“以是生黄钟小素之首”辨讹

小素系小索之讹;小索即律准上的弦索。

Changes in Levels of Endogenous Plant Hormones During Floret Development in Wheat Genotypes of Different Spike Sizes

The levels of endogenous plant hormones regulate floret development and degeneration, and thus grain set in flower crops. This study was undertaken to characterize the changes of endogenous hormone levels during floret development in three wheat ( Triticum aestivum L.) genotypes: “97J1' with the highest grain set and fertile florets per spike, “H8679' with the lowest grain set and fertile florets per spike, and a medium, “YM158'. The results showed that the peak level of ABA appeared between stamen and pistil differentiation and antherlobe formation of floret development, and the timing delayed with the size of spike (earliest in “H8679” and latest in “97J1”). From antherlobe formation to meiosis, the levels of ABA and GA 1+3 decreased sharply in the ears of “97J1”, while in the ears of “H8679” there was only a slight decrease in ABA, and even an increase in GA 1+3 . The ratio of isopentenyladenosine (iPA)/ABA and IAA/ABA in the ears of “97J1” increased sharply from antherlobe formation to meiosis, but changed only slightly in the ears of “H8679”. At antherlobe formation, IAA and GA 1+3 levels were higher in the ears of “97J1”, but lower in the ears of “H8679” than in the leaves. At meiosis, ABA, GA 1+3 and IAA levels in the “97J1” ears were much lower than in the leaves, but similar in “H8679”. These results indicated that the sharp decreases of ABA and GA 1+3 in ears from antherlobe formation to meiosis and the lowest maintenance at meiosis may be favorable for development of fertile florets and enhancement of grain set in wheat.

Effects of Different Concentrations of Homologous Probiotics on Small Intestinal Mucosa Structure of 42-day-old Broilers

In the study, the methods of applied histology and histochemistry were used to determine intestinal villus length, crypt depth, the ratio of intestinal villus length to crypt depth, mucous membrane thickness and intestinal wall thickness of duodenum, jejunum and ileum of 42-day-old broilers, so as to study the effects of different conncentrations of homologous probiottcs on small intestinal mucosa struc- ture of the broilers. The results showed that the effect of 0.3% probiotics on small intestine mucosal structures was the best, such as the length of intestinal villus was the longest, the ratio of villus length to crypt depth was the largest, the thins of mucous membrane and intestinal wall was the thickest. These showed that 0,3% probiotics had best effect on improving and enhancing the digestion-absorption func- tion of the small intestine of the broilers.

Molecular Cloning and Characterization of a DFR from Developing Seeds of Blue-grained Wheat in Anthocyanin Biosynthetic Pathway

Blue-grained wheat derived from the hybrid Triticum aestivum L. X Thinopyrum ponticum (Podp.) Barkworth et D. R. Dewey (Agropyron elongatum (Host) P. Beauv., 2n=70). The molecular biological mechanism of the biosynthetic pathway of blue pigments in the blue grain remains unclear yet. Dihydroflavonol 4-reductase (DFR) is one of the key enzymes controlling flavonoid synthesis in anthocyanin biosynthetic pathway, and may directly participate in the formation of blue pigment in the aleurone layer of blue-grained wheat. Here we cloned a DFR cDNA (TaDFR) from the developing seeds of blue-grained wheat, and four DFR genomic DNAs from Th. ponticum (ThpDFR.t), blue-grained wheat (TaDFR.bg), white-grained offspring of light blue-grained wheat (TaDFR.wg) and Chinese Spring (2n=42) (TaDFR.csg), respectively. TaDFR cDNA encodes a 354 amino-acids polypeptide with high identity to DFR from Hordeum vulgare L. (94%), Oryza sativa L. (83%), Zea mays L.(84%). The result of cluster analysis showed that TaDFR cDNA nucleotide sequence has 100% identity with that of TaDFR.csg. The four DFR genomic DNAs have extraordinary high homology and each has three introns. The differences of the four DFR genomic DNAs mainly exist in introns. Southern blotting analysis showed that there are at least 3-5 DFR copies in wheat, the copy numbers in different color grain wheats are not significantly different. The hybridization band patterns were the same, but different from that of Th. ponticum. DFR in blue-grained wheat belongs to a DFR superfamily. Northern blotting analysis indicated that the DFR expressed in the developing seeds of both blue- and white-grained wheat at 15 d after flowering (DAF), the mRNA levels of DFR reached the highest at 18 DAF, then declined quickly and disappeared at 33 DAF But the expression levels in blue-grained seeds were higher than that in white grain at the same seed developing stages. DFR transcripts accumulated in young leaves, and leaf sheaths of blue- and white-grained wheat and Th ponticum, but not detected in roots from different color wheats and developing seeds of Th. ponticum. Results indicated that there may exist some regulatory gene(s) which can increase the expression of DFR in the aleurone layer of blue-grained wheat, and thus resulting in the formation of blue pigments.

Structural Characteristics of Thicker-culms in the High-yield Wheat Cultivars

The culm of the Triticum aestivum L. cv. “Lankao 906_4”, a high_yield cultivar, in comparison with “Jing 411”, a widely_planted cultivar, was studied by means of anatomical technique coupled with mechanical and chemical theory. A anatomical analysis revealed that “Lankao 906_4” possessed thicker mechanical tissue and larger vascular bundle area than those of “Jing 411”. In terms of the resistance to lodging, “Lankao 906_4” had higher culm strength. Furthermore the content of lignin was semiquantitatively analyzed with confocal laser scanning mircoscope (CLSM), and revealed a much higher lignin content in the culm of “Lankao 906_4” than that in the culm of “Jing 411”. All of these indicated that the characteristics of culm were important factors in breeding the super_production wheat cultivar.

Correlation between Carotenoids Content and Several Quality Traits of Wheat Varieties

A total of 31 wheat varieties（lines） released in different years in Huanghuai Area were selected as materials so as to study the carotenoids content,lipoxygenase activity, and some other quality traits of wholemeal. Results showed that carotenoid content and other quality traits had highly significant differences among varieties. Carotenoids content was significantly positive correlated with watersoluble pentosan and yellowness. Carotenoids content was significantly negative correlated with peak viscosity, hold through, breakdown, final viscosity, unit weight,formation time, and was negative correlated with peak time, protein content and stability time. According to cluster analysis, carotenoid contents in 31 varieties were divided into three major groups： one group had common carotenoid content, which included 19 varieties such as Meng 0318; one group had relatively low carotenoid content, which included 10 varieties such as Luomai23; and the last group had relatively high carotenoid content, which included 2 varieties such as Huaimai22. The average carotenoid contents of the three groups were 1.93, 1.07 and 2.99 mg/kg respectively.

Effect of Echinacea Polysaccharide on Secretion of TNF-α mRNA by IEC-6 Injured by LPS

Objective] This study was conducted to investigate Echinacea polysaccha-ride （EPS） on expression of tumor necrosis factor （TNF） under injury of intestinal epithelial cel s （lEC-6） by lipopolysaccharide （LPS）, so as to discuss the action mechanism of EPS to injured cel s. [Method] Total DNA was extracted with TRlzon reagent, TNF-α mRNA was amplified, and the amplification products were subjected to agarose gel electrophoresis and imaging. [Result] 50 μg/ml EPS could partial y in-hibited the production of TNF-α mRNA by lEC-6 under the stimulation of LPS, while the inhibition of 200 and 500 μg/ml EPS on the level of TNF-α mRNA gradual y in-creased with the concentration increasing; and lEC-6 cel s pretreated with 50, 100, 200 and 500 μg/ml EPS for 24 h and then stimulated by 10 μg/ml LPS for 1 and 4 h were analyzed by RT-PCR method, and it was found that the expression of TNF-α mRNA induced by LPS could be effectively inhibited by EPS, and the inhibition rate at 4 h was higher than that at 1 h. [Conclusion] EPS could play its role of protecting intestinal mucosa by inhibiting the secretion of TNF-α mRNA by cel s un-der the stimulation of LPS, and such inhibition effects of EPS had concentration dependency and time dependency.

Interaction between Mitomycin C and DNA at Paraffined Graphite Electrode

Aim To investigate the electrochemical behaviors of Mitomycin C （MC） and its interaction with calf thymus DNA （ctDNA）. Methods The cyclic vohammetry （CV） was carried out at a paraffined graphite electrode. Results MC showed a well-defined oxidation-reduction peak. As a result of reaction with ctDNA, the peak current of MC decreased apparently. According to corresponding electrochemical equations, the diffusion coefficient of both free and MC-DNA complex have been determined, and the heterogeneous rate constants were also obtained simultaneously. Conclusion The solid paraffined graphite electrode could be used to estimate parameters of the interaction between DNA and MC, and provide the convenient and sensitive analysis.

Cumulative Toxicity of Residue Degradation Products of Penicillin Bacteria

[Objective] The research aimed to discuss the accumulation of toxic slag of penicillin bacteria residue degradation products and explore its ability to meet the aquaculture industry as a protein feed into development and utilization conditions.[Method] Through the sub-acute toxicity tests in mice strains,which were fed by different doses of penicillin bacteria residue degradation products （3% and 6%） under continuous observation of 15 weeks,recording a weekly mouse weight and death,and sampling executed after the test,animal liver and kidney function were blood test,taking heart,liver,spleen,kidney weighing,as well as liver and kidney pathology observed in the optical microscope.[Result] There were no significant differences （P 0.05） between the test group mice body weight,mortality and liver and kidney function and the control group within 15 weeks.Low-dose test group could be seen the liver cells,renal tubular epithelial nuclei broken,and a small number of liver and kidney cells with mild edema.High-dose test group could be seen in liver tissue of mice nuclei fragmentation and a fat droplets,the majority of liver cells,edema,and only a small number of liver cells,there were no significant changes.Renal portal area showed inflammatory cell infiltration,renal tubular epithelial cells,edema and necrosis.[Conclusion] In this experimental condition,the degradation products of penicillin bacteria residue played a mild toxcity on organ parenchymal cells in mice.

Effects of Berberine on TXB 2 and 6 Keto PGF 1α Plasma Levels in Rabbits with Uncomplete Cerebral Ischemia

Effects of berberine (Ber) on platelet aggregation and TXB2 and 6 keto PGF1a plasma levels were studied in rabbits with uncomplete cerebral ischemia. Ber inhibited uncomplete cerebral ischemic rabbit platelet aggregation triggered by collagen, ADP, and arachidonic acid (AA) with the IC 50 of 0.15, 0.46, and 0.51 mg·ml 1 , respectively. In rabbits, Ber 25, or 50 mg·kg 1 iv 30 min after uncomplete cerebral ischemia, restrained the collagen ADP and AA induced platelet aggregation determined 90 min later. With radioimmunoassay, we measured the thromboxane B2 (TXB 2) and 6 ketoprostaglandin F 1α (6 keto PGF 1α ) contents in rabbit plasma. The results indicated that the TXB 2 level in rabbit 120 min after uncomplete cerebral ischemia (921±539 pg·ml 1 ) was higher than that (230±71 pg·ml 1 ) in normal rabbits ( P < 0.01), but 6 keto PGF 1α level after ischemia (73±23pg·ml 1 ) was lower than that (262±988pg·ml 1 ) in normal rabbit. Ber (5, 25 or 50 mg·kg 1 ) reduced obviously the plasma TXB 2 level in rabbit with uncomplete cerebral ischemia (504±196, 386±174, or 272±183 vs 921±539 pg·ml 1 , respectively, P < 0.01). We conclude that the decrease of TXB 2 content is one of the possible mechanisms of Ber anti cerebral ischemic effect.

Anemia in Rural China’s Elementary Schools: Prevalence and Correlates in Northwest Area

[Objective] The goal of this paper was to measure anemia prevalence and identify factors that correlate with anemia among school-aged children in rural areas, provide a scientific basis for effective prevention and treatment. [Method] The data set covered three provinces in northwest area. We detected hemoglobin of the sample pupils randomly chosen from the 3rd-6th grade of 305 rural elementary schools in 26 poor counties, and carried out questionnaires among them. [Result] 25.24% of the pupils had anemia, most of them were girl and the lower grade stu- dents. The multiple-regression revealed that the eating habits and family condition had certain impact on their anemia. [Conclusion] Anemia is still a serious problem of rural pupils. Improving diet conditions, providing balanced meals, enhancing the knowledge of the principals, teachers and parents about anemia and the importance of students＇ nutritional status and health contribute to the prevention and treatment of anemia of rural pupils.

Effects of Shikonin on Proliferation, Apoptosis, and Extracellular Matrix of Human Mesangial Cells

Objective:To investigate the effect of shikonin on the proliferation, apoptosis and extracellular matrix (ECM) of human mesangial cells (MC). Methods: MC was cultured in vitro with different concentrations of glucose (30, 50, 80 mmol/L). The cell growth was observed by using MTT method and apoptosis by using an aunexin-V-Fluos. Immunohistochemical studies for Laminin (LN), Fibronectin (FN) and type Ⅳ Collagens (Col Ⅳ) were measured. Results: Shikonin inhibited their growth (P<0.05) and apoptosis in the glycated cultured cells. Shikonin 0.05 mmol/L significantly reduced the secretion of LN, FN and Col Ⅳ from MC (P<0.05) cultured in 30, 50 and 80 mmol/L glucose. Conclusion: Shikonin could prevent or treat diabetic nephropathy (DN) and glomerulosclerosis (GS).

Effect of Copper and Zinc on Accumulation of Vitamin E in Wheat Embryo-derived Callus

[Objective] The aim was to study the effect of the content of copper and zinc on in medium the vitamin E accumulation in wheat embryo-dreived callus.[Method] The mathematical models were established to describe the growth kinetics and the vitamin E accumulation in wheat embryo callus cells.With the aim of getting the highest accumulation of the secondary metabolite Vitamin E,the optimal combination of copper and zinc in medium was confirmed by testing.[Result] The results showed that the production of vitamin E in B5 medium reached the highest value with 2.0 mg/mL ZnSO4·7H2O and 0.1 mg/mL CuSO4·5H2O.The fitting degrees of kinetic models of vitamin E accumulation and cell growth were 97.53% and 95.60%,respectively,which indicated good nonlinear relationships.[Conclusion] Both copper and zinc could affect the accumulation of vitamin E in wheat germ callus,and Copper showed more prominent effect than Zn.Synergism existed in low copper and zinc concentration,and the inhibitive effect enhanced with the increase of the concentrations.

Antirejection therapy with Tripterygium woifordii and low-dose cyclosporine in small bowel transplantation in pigs

AIMS Antirejection therapy with tripterygium wolfordii(TW) and low-dose cyclosporine(CsA)was better than treatments with large dosage CsA in small bowel transplantation. METHODS This paper presents the experiment of two step segmental small bowel transplantation with TW,a traditional Chinese medicine and low dose CsA in pigs. RESULTS Rejection was developed in Group I without im- munosuppression as well as in Group Ⅳ treated with low-dose CsA.The mean survival time of grafts was 12.8±2.7days and 12.4±2.6 days respectively.The animals of Group Ⅱ were treated with high-dose CsA for 100 days and then with TW.in which two pigs were killed for severe pneumonia on day 92,97 and two pigs survived more than 348 and 327 days respective- ly.Five animals in Group Ⅲ in which TW and low-dose CsA were administered for 100 days and then TW was the only drug used in living animals,survived 243.2±90.9 days,none of which succumbed to infection. CONCLUSIONS:We are the first to use TW in small bowel transplantation and f Group Ⅰ(n=10):control group,received no immunosuppression.

Cloning and Expression Analysis of Violaxanthin De-Epoxidase (VDE) cDNA in Wheat

Violaxanthin de-epoxidase (VDE) is the key enzyme in the xanthophyll cycle and protects plant photosynthetic apparatus from the damage of excessive light. A wheat (Triticum aestivum L cv. Xiaoyan 54) VDE cDNA was obtained using RT-PCR method. Its deduced protein sequence shares high identity with that of Arabidopsis and rice. Southern blot revealed that there are three copies of VDE gene per haploid genome of wheat. VDE transcript levels were higher in green leaf than in root, seed and etiolated leaf. Northern blotting analysis indicated that VDE mRNA level is induced during greening process of etiolated wheat seedling and increased by intense light illumination.

Effects of Vegetation Coverage and Management Practice on Soil Nitrogen Loss by Erosion in a Hilly Region of the Loess Plateau in China

Soil erosion and nutrient loss due to erosion are world-wide problems. Similar to soil loss by erosion, soil nitrogen (N) loss by erosion in small catchments is affected by vegetation coverage. The practice of comprehensive management for catchments mainly by adjusting cropland, grassland and woodland areas was widely adopted to reduce soil and water loss in catchments of the Chinese Loess Plateau. Three experiments under natural and artificial rainfall conditions on N loss by erosion for a model catchment and for an actual catchment in Zhifanggou of Ansai County in China was performed to determine the relationships between comprehensive management and N loss by runoff in small catchments. The results for vegetation coverage of 60%, 40%, 20% and 0 show that runoff loss of ammonium, nitrate, and total N were 87.08, 44.31, 25.16, 13.71 kg/km(2); 85.50, 74.06, 63.95, 56.23 kg/km(2); and 0.18, 1.18, 1.98, 7.51 t/ km(2), respectively. Due to reduction in the size of cropped area on steeply sloping land, soil N loss by erosion in the catchments was decreased by 15.8% as compared with that in 1992, i.e., from 8 758.5 kg in 1992 to 7 562.2 kg in 1998. Whereas, catchments act as a filter for ammonium and nitrate in rain, the catchment filtering effects on nitrate is remarkably higher than that on ammonium. The enrichment of < 20 mum aggregate in sediment results in the enrichment of organic matter and total N in flood sediment. Greater vegetation coverage can effectively decrease soil erosion and total N loss. However, soil mineral N loss increased as vegetation coverage increased.

Abnormal Change in Body Weight and Non-Fasting Blood Glucose Levels of Mouse Strain C57BL/6J in Generating Type 2 Diabetes Model

The commercially available inbred obesity-prone C57BL/6J （B6） and outbred stock ICR mice （3-week old） purchased from a breeder of Beijing were weaned onto high-fat diet （HFD）, HFD-3% fructose water （HFDF） and standard rodent chow, respectively. After exposure to the diets for six weeks, HFD and HFDF fed mice were injected intraperitoneally with streptozotocin （STZ, 100mg/kg body weight） and kept on the same diet for next four weeks. Body weight was recorded weekly. Non-fasting blood glucose levels of HFD and HFDF fed mice were measured before and after STZ injections. The body weight of HFD-fed and HFDF-fed B6 mice were significantly lower than that of the control, but body weight of HFD-fed and HFDF-fed ICR mice were significantly higher than that of the control. After injection of STZ, blood glucose levels were above the stardardized criterion （11 mmol/L） for the diabetes mouse model in both HFD and HFDF fed ICR mice, but reverse in B6 mice. The type 2 diabetes model was generated successfully in ICR but not in B6 mice, regardless of whether fructose was supplied. The current results indicated that ICR mouse is still a useful and economical strain for HFD-induced/STZ-treated type 2 diabetes model, and that some variation may occur in the genetic composition among B6 mice bred by different breeders.

Comparative Study on Photoinhibition Between Two Wheat Genotypes

Changes in the efficiency of the primary light energy conversion, fluorescence quenching parameters and contents of photosynthetic pigments were compared between two wheat ( Triticum aestivum L.) genotypes in response to high light stress. The contents of chlorophyll and carotenoid in “Jing_411' were slightly higher than those in “Xiaoyan_54'. Under high light stress, photoinhibition as indicated by a sustained decrease in PSⅡ photochemical efficiency was more pronounced in “Jing_411' than in “Xiaoyan_54'. The content of ascorbate and the activity of the deepoxidase were higher in “Xiaoyan_54' than in “Jing_411'. The genotypic difference in resistance to photoinhibition is related to the capacity to dissipate the excess energy nonradiatively.

Isolation and Purification of Gonyautoxins from Two Strain of Alexandrium minutum Halim

Aim To study isolation and purification of Gonyautoxins from two differentstrains of Alexandrium minutum Halim. Methods Ethanol extracts of the two culture strains ofAlexandrium minutum Halim were fractionated by gel filtration and ion exchange chromatography toobtain gonyautoxins. The toxin profiles were tested by HPLC method. Results Both strains containgonyautoxin-1, gonyautoxin-2, gonyautoxin-3 and gonyautoxin-4. The total gonyautoxin content ofAmtk4 strain is almost 10 times higher than that of Amtk2 strain. Conclusion Alexandrium minutumHalim Amtk4 strain is suitable for the preparation of Gonyautoxins.

Nitrogen Cycling and Losses Under Rice-Wheat Rotations with Coated Urea and Urea in the Taihu Lake Region

A lysimeter experiment with undisturbed soil profiles was carried out to study nitrogen cycling and losses in a paddy soll with applications of coated urea and urea under a rice-wheat rotation system in the Taihu Lake region from 2001 to 2003. Treatments for rice and wheat included urea at conventional, 300 （rice） and 250 （wheat） kg N ha^-1, and reduced levels, 150 （rice） and 125 （wheat） kg N ha^-1, coated urea at two levels, 100 （rice） and 75 （wheat） kg N ha^-1, and 150 （rice） and 125 （wheat） kg N ha^-1, and a control with no nitrogen arranged in a completely randomized design. The results under two rice-wheat rotations showed that N losses through both NH3 volatilization and runoff in the coated urea treatments were much lower than those in the urea treatments. In the urea treatments N runoff losses were significantly （P 〈 0.001） positively correlated （r = 0.851） with applied N. N concentration in surface water increased rapidly to maximum two days after urea application and then decreased quickly. However, if there was no heavy rain within five days of fertilizer application, the likelihood of N loss by runoff was not high. As the treatments showed little difference in N loss via percolation, nitrate N in the groundwater of the paddy fields was not directly related to N leaching. The total yield of the two rice-wheat rotations in the treatment of coated urea at 50% conventional level was higher than that in the treatment of urea at the conventional level. Thus, coated urea was more favorable to rice production and environmental protection than urea.