英语作文 environmentrt 急需一片有关environment的作文,thanks!

英语作文 environmentrt 急需一片有关environment的作文,thanks!
英语作文 environment
rt 急需一片有关environment的作文,thanks!

英语作文 environmentrt 急需一片有关environment的作文,thanks!
The world we live in is becoming more and more intolerable because of environmental destruction. For example , forest destruction results in decrease of planting land and unpleasant weather. In addition, man is faced with problems of water pollution and air pollution.
A lot of measures have been taken. Planting trees helps improve and beautify the environment. Besides, laws concerning environmental protection have been put into effect and achieved good results.
However, the problem of environmental protection remains far from being solved. On the one hand, the environment pollution and destruction are getting worse and worse in the modern world. On the other hand, the lack of knowledge about the importance of protecting environment hinders the solving of the problem. In a word, there is a long way to go before we enjoy a clean and comfortable world.

Tests eight SDS- polyacrylamide gel electrophoresis examination extraneous source protein expression [experiment principle] the SDS- polyacrylamide gel electrophoresis (SDS-PAGE) is one method which i...

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Tests eight SDS- polyacrylamide gel electrophoresis examination extraneous source protein expression [experiment principle] the SDS- polyacrylamide gel electrophoresis (SDS-PAGE) is one method which in the protein analysis uses frequently. It is (SDS) as well as qiu the base ethyl alcohol heats up together the protein sample homo-ion abstergent lauryl sodium sulfate, causes the protein to denaturate, between the multi-peptide chain interior and the peptide chain disulphide group returns to original state, the peptide chain is opened. Opens peptide chain depending on sparse water function and SDS union, but has the negative charge, when electrophoresis under electric field function, peptide chain in gelatin to positive electrode migration. Because different size peptide chain in migration time receives the resistance is different, separates gradually in the transition process, its relative transport ratio and the molecular weight logarithm becomes the linear relations. pGLO is the green fluorescence protein (GFP) the gene clone the expression vector after the pectin sugar start one kind. Carries has the pGLO backwoods coli to include the corresponding inductor and under the antibiotic condition raises, may express GFP, this compares does not add the inductor the same backwoods coli on the SDS-PAGE gelatin to an obvious banding. The expression protein also available non-denatured polyacrylamide gel electrophoresis examination, under after the visual purple lamp may see the induction the sample to have the green fluorescence banding on the gelatin to appear. May also dyes (Western-blotting) through the immunity signature the method, examines the expression with the GFP immune body the extraneous source protein. [instrument, material and reagent] (1) instrument 1. vertical board electrophoresis tank and necessary glass plate, comb 2. electrophoretic apparatus 3. dry constant temperature culture dish 4. microwave oven (2) material 1. pGLO expresses backwoods coli's culture medium which the material particle transforms: And has not added the pectin sugar induction with the pectin sugar induction (3) reagent 1.1.5mo1/L TrisHCl pH 8.8 (added SDS) 2.0.5mo1/L TrisHCl pH 6.8 (added SDS) 3.10%SDS 4.30%Acr/Bis 29.2g Acr + 0.8gBis, with double steams the water constant volume to 100mL, the filtration spare, 4℃ depositing. 5.10%Ap (- 20℃ depositing) 6.2x sample buffer solution 0.5mo1/L TrisHCl pH6.8 2mL Glycerine 2mL 20%SDS 2mL 0.1% tetrabromophenol sulfonphthalein 0.5mL 2-- qiu base ethyl alcohol l.0mL Double steams the water 2.5mL 7.5x electrode buffer solution Tris 7.5g G1y 36 g SDS 2.5g Double steams the water to dissolve, constant volume to 500mL, when use dilutes 5 time of uses 8. dye liquor: 0.2g tests Mas light blue R250 + 84mL 95% ethyl alcohol + 20mL glacial acetic acid, the constant volume to 200mL, the filtration spare. 9. destaining solution: Ethyl alcohol: Glacial acetic acid: Water =7.5: 7.5:85 [laboratory procedure] the 1. assembly makes the glass plate which the rubber uses " the sandwich ": Makes the 1.0mm thick rubber. The choice both sides' glass gibs is the 1mm glass plate, gibs the surface it to place on the tabletop toward the first tone, gibs the gray U shape silica gel at above suspends, above then brings two “the ear” the concave glass places, causes the U shape silica gel to gib smoothly, clamps docile between two glass plates. “The sandwich” puts carefully this glass plate “the handbasket rack” on, with the plastic “the wedge” the clamp, pays attention to the base the U shape silica gel to gib in the clamp process still maintains is smooth, is docile. In glass plate “sandwich” the crevice tops up the distilled water, examines whether to leak, if the water leakage must the rewiring. the 2. configuration density is 12% separation rubber (gelatin density should act according to is separated protein molecular weight to carry on choice), the formula is as follows: Double steams the water 3.3 mL 1.5mo1/L TrisHCl (pH 8.8) 2.5 mL Acr/Big(30%) 4.0 mL 10% SDS 100 µ L TEMED 10 µ L 10%AP 100 µ L Bulk volume 10 mL (just fills system two rubber) Mixes uniform add-on enters in two glass crevices, and was careful that joins the 1cm distilled water on the rubber surface (to add distilled water on rubber surface to call hydraulic packing, goal is maintains rubber surface is smooth, and prevents rubber and air contact, affects rubber polymerization), the room temperature laying aside, after and so on rubber condense naturally, (this time between rubber surface and hydraulic packing clear boundary, leans obviously) the hydraulic packing. By now might start to compound 4% concentration rubber, the formula is as follows: Double steams the water 1.8 mL 0.5mo1/L TrisHCl pH 6.8 0.75mL Acr/Bis (30%) 0.4 mL 10% SDS 30 µ L TEMED 5µ L 10%Ap 30µ L Bulk volume 3.0 mL (suffices to make two blocks concentration rubber) Mixes uniform add-on enters " the sandwich " in the glass plate crevice, then, in inserts the 1mm comb in the concentration rubber, pays attention do not leave leeway the air bubble between the comb and the concentration rubber. If discovered that has the big air bubble, certainly wants the idea to remove (may insert pulls out comb or refers to ball air bubble place glass and so on), will otherwise affect the electrophoresis result. After treating the concentration rubber coagulation, draws out the comb carefully. Between the Canadian type hole gap which if after discovering draws out comb, forms to have the distortion, is careful with injector's needle reorganizes, causes it to be neat. 3. bacterium culture medium SDS-PAGE sample manufacture: Simultaneously makes the L- pectin sugar induction and has not added the L- pectin sugar two backwoods coli type. Takes bacterium culture medium 1.5mL to add to the 1.5mL small centrifuge tube, the 12000r/m offcenter 3 minutes, go on clear. In the offcenter precipitates adds approximately waits for the volume the distilled water, blows bugle and beats drums carefully with the spear head, causes the bacterium full aerosol, until the obvious small briquetting, then has not joined and so on volumes 2× the sample buffer solution, in 100℃ boils the water bath (or dry culture dish) keeps warm 5min. This time like with the spear head absorption sample, will discover that will stick thickly, will assume the nasal mucus shape, this will be because will have in the sample to include the massive DNA result. Must use the insulin injector to split out the sample from the extremely thin needle, can the DNA member interruption, cause many times repeatedly the sample becomes no longer sticks thickly up. The sample 14000r/m offcenter 5 minutes, causes the insoluble substance precipitation to get down, in careful absorption clear Canadian type. The electrophoresis sample's processing direct relation electrophoresis result's quality, needs certainly to make the type earnestly, otherwise cannot run the good rubber. 4. agar-agar back cover: After completing the rubber, “the sandwich” takes out the glass plate from the rack, gibs two glass plate's between silica gel removes. After removing gibs, in the gelatin base will leave behind a crevice, this crevice must use 2% melted the agar-agar stuff, otherwise, in the glass plate soaks after the electrode buffer solution in the crevice air will be very difficult to remove thoroughly, when electrophoresis will affect the electric conduction obviously, will be serious when will cause the entire electrophoresis defeat. When agar-agar back cover pays attention do not the sparging. 5. electrophoresis tank assembly: After the back cover, glass plate “sandwich” concave glass face inward heavy new clothing “handbasket rack” on, after fixed good, puts the entire part to the electrophoresis tank outer covering, however add-on electrode buffer solution. Adds when the fluid inside and outside must make the liquid level basic contour, in the tank liquor liquid level must be higher than the glass plate “the sandwich” concave glass 5mm, guarantees at least can the electric conduction, and the electric field is even. 6. adds the type: According to designs the good order with to add the type quantity beforehand to add the type in turn. In the sample density unknown situation, an identical sample coca gradient, namely each swimming lane's Canadian type quantity halves in turn. Thus, when makes the second electrophoresis may its achievement reference, correct Canadian type. The protein molecular weight standard may add in depends on the middle Canadian type hole, also the coca in (a sample which place will most keep to the side to side 2nd will obviously often run slanting). 7. electrophoresis: Covers the electrophoresis tank cover, receives on the electrophoretic apparatus the electrophoresis tank two electrodes (to pay attention to electrode not to meet wrong), then puts through the power source. Adjusts the first voltage 80V, when the sample enters the separation rubber, the adjustment voltage causes constantly at 150V. When the tetrabromophenol sulfonphthalein moves arrives to the base approximately 0.5cm, switches off the power source, stops the electrophoresis. Takes out the glass plate from the electrophoresis tank, pries open two glass plates carefully with the old calling card, exposes the rubber surface. Will concentrate the rubber part to remove does not want, the separation rubber puts to the potted molded case in dyes. 8. dyeing and decolorization: The gelatin in tests in the Mas light blue dye liquor to dye 20 minutes (on table slow vibration), however the caster goes to the dye liquor (dye liquor recycling, may use dozens of times repeatedly), with the laundering several, removes on the gelatin and potted molded case's dyeing residue originally, adds the destaining solution to decolorize (on table slow vibration), 1 hour later trades one time the destaining solution, the vibration decolorization over night. After the thorough decolorization's gelatin protein banding is clear, background transparent clean. By now might carries on the gelatin photograph or with the scanner the scanning, takes the permanent record. [experimental result] On after dyeing polyacrylamide gelatin obviously many every large or small bandings. Compared with two backwoods coli sample, with has not added the pectin sugar induction after the pectin sugar induction, the former in approximately the 25kD place obvious many banding, this is the position which GFP is. tests nine GFP immunity signature [experiment principle] The immunity signature (Western blotting or Immunoblotting) generally by the gel electrophoresis, the sample signature and the immunology examine three parts to be composed. First step makes the SDS polyacrylamide gel electrophoresis, causes in the testing sample the protein to divide into the belt according to the molecular weight size in the gelatin. Second step has divided into the gelatin in the banding the protein to shift to one kind of solid phase backing, with most materials is the nitrocellulose membrane (the NC membrane) and the PVDF membrane, the protein shift method multipurpose electrophoresis shift (shift electrophoresis), it also has the semi-dry process and the aqueous method division. Third step was examines already the signature with the specificity immune body the corresponding antigen which must study on the membrane. The immunity examination's method may be direct and indirect. Now the multipurpose indirect immunity enzyme sign's method, after using the specificity first immune body dyeing, then uses (anti-first immune body immune body which the enzyme sign the second immune body the alkalinity phosphatase (Ap) or the horse radish peroxide enzyme (HRP) marks) to dye, adds the enzyme again the substrate coloration, the exposure banding demonstrates the antigen through the membrane on color or on X light negative the existence. In order to enable the beginner the goal protein which observes in the experiment process must examine, this experiment uses the right and wrong denaturates the polyacrylamide gel electrophoresis, maintains GFP the natural activity, carries on tracing using the fluorescence to it. In addition, in the experiment substitutes for the second immune body with domestically produced HRP mark protein A, by saving of expense. Protein A is can distinguish many kinds of animal IgG from the bacterium separation one kind the protein, it may take the second immune body in many situations the substitute. Similarly is for the saving of expense, in the experiment (the AC membrane) replaces the nitrocellulose membrane with the acetyl cellulose membrane (the NC membrane), like this must be much cheaper, but effect actually not wide difference. The first part: GFP extract under non-denatured condition polyacrylamide gel electrophoresis Under the non-denatured condition's polyacrylamide gel electrophoresis, does not contain S except the reagent in

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