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Specificity, restriction

Lead acetate can be used only for coloring scalp hair at a level not to exceed 0.6%, as lead, weight/volume of the product. The regulations provide specific restrictions (including label specifications) that lead acetate must not be used to color mustaches, eyelashes, eyebrows, or hair on parts of the body other than the scalp. [Pg.458]

Colorants can only be used ia those medical devices cited. Colorants without specific restrictions regarding quantity can be used ia amounts not to exceed the minimum reasonably required to accomplish the iatended coloring effect. [Pg.440]

The chemical and solvent processes previously discussed remove acid ga from the gas stream but result in a release of H2S and CO2 when the solvent is regenerated. The release of H2S to the atmosphere may be limited by environmental regulations. The acid gases could be routed to an incinerator or flare, w hich would convert the HiS to SO2. The allowable rate of SO2 release to the atmosphere may also be limited by environmental regulations. For example, currently the Texas Air Control Board generally limits H2S emissions to 4 Ib/hr (17.5 tons/year) and SO2 emissions to 25 tons/year. There are many specific restrictions on these limits, and the allowable limits are revised periodically. In any case, env ironmental regulations severely restrict the amount of H S that can be vented or flared in the regeneration cycle. [Pg.172]

The primary objective of Phase II trials is to explore therapeutic efficacy in patients. The number of subj ects may range from 50 to 5 00, and patients may be selected based on specific restrictive criteria for example, those suffering only from the condition under study, disease stage, age, and so on. An important goal for this phase is to... [Pg.74]

Since the 1993 court decision against Barr Laboratories, 5 tjjg elimination of outliers has taken on a decidedly legal aspect in the U.S. (any non-U.S. company that wishes to export pharmaceuticals or preciwsor products to the U.S. market must adhere to this decision concerning out-of-specifica-tion results, too) the relevant section states that ... An alternative means to invalidate an individual OOS result... is the (outlier test). The court placed specific restrictions on the use of this test. (1) Firms cannot frequently reject results on this basis, (2) The USP standards govern its use in specific areas, (3) The test cannot be used for chemical testing results. ... A footnote explicitly refers only to a content uniformity test, 5 but it appears that the rule must be similarly interpreted for all other forms of inherently precise physicochemical methods. For a possible interpretation, see Section 4.24. [Pg.61]

Marsh M, Bron R. SFV infection in CHO cells cell-type specific restrictions to productive virus entry at the cell surface. J Cell Sci 1997 110 (Pt 1) 95-103. [Pg.289]

It is clear that both intact cell MALDI-TOF and PFGE have their limitations. PFGE analyses probes the chromosomal DNA of microorganisms for variations in the locations of specific restriction enzyme cleavage sites, while MALDI-TOF mass spectrometry of intact cells primarily examines abundant proteins such as ribosomal proteins35 and those associated with or near bacterial cell walls.58 In order for MALDI-TOF to detect a variation, a mutation must lead to noticeable changes in the expression of cell wall—associated... [Pg.195]

Restriction fragment length polymorphism (RFLP) Variation between individuals in DNA fragment sizes cut by specific restriction enzymes. RFLPs are usually caused by mutation at a cutting site. [Pg.537]

Evaluation is based on specific restrictions and limitations of reactions in the sequence, the availability of materials, and other factors. [Pg.178]

A RESTRICTION MAP is used to identify and locate specific restriction sites on a given piece of DNA. The size of a fragment is determined by running the restriction digest on an agarose gel. Fragments separate by size—the smaller ones move farther toward the bottom of the gel. [Pg.76]

The sequence of DNA recognized by a specific restriction endonuclease is often palindromic. A palindrome is something that reads the same way backward and forward (Fig. 6-2). The sequence of the bottom strand read in the 5 to 3 direction is the same as that of the top strand read in the 5 to 3 direction. The usual analogy for a verbal palindrome is a sentence that reads the same way backward and forward. Madam, I m Adam is the usual example. It s not exactly the same way for DNA palindromes. The top strand does not read the same from the left as from the right the top strand read from left to right is the same as the bottom strand read from right to left. [Pg.77]

Phosphatases are numerous and important enzymes (see also Chapt. 2). They are classified as phosphoric monoester hydrolases (phosphatases, EC 3.1.3), phosphoric diester hydrolases (phosphodiesterases, EC 3.1.4), triphosphoric monoester hydrolases (EC 3.1.5), diphosphoric monoester hydrolases (pyrophosphatases, EC 3.1.7), and phosphoric triester hydrolases (EC 3.1.8) [21] [63]. Most of these enzymes have a narrow substrate specificity restricted to endogenous compounds. However, some of these enzymes are active toward xenobiotic organophosphorus compounds, e.g., alkaline phosphatase (EC 3.1.3.1), acid phosphatase (EC 3.1.3.2), aryldialkylphosphatase (para-oxonase (PON1), EC 3.1.8.1) and diisopropyl-fluorophosphatase (tabunase, somanase, EC 3.1.8.2) [64 - 70]. However, such a classification is far from definitive and will evolve with further biochemical findings. Thus, a good correlation has been found in human blood samples between somanase and sarinase activities on the one hand, and paraoxonase (PON1) type Q isozyme concentrations on the other [71]. [Pg.567]

The sequences are written 5 —3 in the top strand and 3 —5 in the bottom strand. The phosphodiester bonds cleaved by each enzyme are marked T in the top strand and T in the bottom strand. The shorthand used to identify specific restriction enzymes can be confusing to a student reading a scientific paper, in which the shorthand is not explained. [Pg.57]

For major investigations, regulatory authorities, such as US OSHA or the US EPA, may deny access to the site until certain precautions are established or until certain tests are completed. Restart may also require agency approval. Often, special measures are required following an incident because of the unusual conditions of the process. One example of such special measures is extensive reliance on fall protection measures as a substitute for normal scaffolding. Insurance or legal representatives may also impose specific restrictions on the team s activities. [Pg.121]

It was demonstrated by Sundman (1985) and later by Ansara et al. (1988) that an order-disorder transformation could be modelled by setting specific restrictions on the parameters of a two>sublattice phase. One of the first phases to be considered was an A B-ordered compoimd. In such circumstances the sublattice formula A, B)j(A, B) can be applied and the possible relationships between site fiactions and mole fiactions are given in Figure 5.6. The dashed lines denoted xb = 0.25, 0.5 and 0.75 show variations in order of the phase while the composition is maintained constant. When these lines cross the diagonal joining AjA and B3B the phase has disordered completely as Vb Vb As the lines go toward the boundary edge the phase orders and, at the side and comers of the composition square, there is complete ordering of A and B on the sublattices. [Pg.123]

Digest the vector with specific restriction enzymes to generate ends compatible for ligation with the coding sequence to be cloned. [Pg.3]

Digest the insert with specific restriction enzymes. [Pg.3]

The importance of NMR in phosphorus chemistry is today not a matter for dispute—this was already clearly evident at the time of writing my earlier review on this topic/1986,15 This earlier review was concerned with nearly four hundred and fifty publications from the early days of NMR (about 1950) until the end of 1965. Papers specifically restricted to 31P data were not included but these were, however, reviewed by Van Wazer et a/.(1967,1> who at approximately the same time presented results for about three thousand compounds. [Pg.1]

Multiplex PCR amplification can apparently tolerate degraded DNA because the size of PCR products generated for subsequent hybridization is 100 50 base pairs. However, the 10 K mapping array and the 100 K and 500 K arrays use a specific restriction enzyme to digest the genomic DNA for subsequent ligation with a specific DNA linker. The DNA linkers then act as binding sites for the specific primer to initiate PCR amplification... [Pg.80]

Introduction of a foreign DNA molecule into a replicating cell permits the amplification (that is, production of many copies) of the DNA. In some cases, a single DNA fragment can be isolated and purified prior to cloning. More commonly, to clone a nucleotide sequence of interest, the total cellular DNA is first cleaved with a specific restriction enzyme, creat-... [Pg.446]

A restriction map of plasmid pBR322 indicating the positions of its antibiotic resistance genes and the sites of nucleotide sequences recognized by specific restriction endonucleases. [Pg.449]

In zeolites the mobility of hydrocarbon molecules with double bonds is specifically restricted because of a specific interaction between the 7r-elec-trons and the zeolite (2). As expected, proton spin relaxation of benzene, cyclohexadiene, cyclohexene, and cyclohexane adsorbed on NaY reveals an increasing restriction of mobility with increasing number of -electrons (8, 4, 8). This is shown in Figure 1, where the longitudinal (7 ) and transverse (T2) proton relaxation times are plotted. [Pg.431]


See other pages where Specificity, restriction is mentioned: [Pg.458]    [Pg.46]    [Pg.348]    [Pg.175]    [Pg.29]    [Pg.353]    [Pg.18]    [Pg.836]    [Pg.117]    [Pg.538]    [Pg.78]    [Pg.41]    [Pg.821]    [Pg.65]    [Pg.290]    [Pg.13]    [Pg.278]    [Pg.298]    [Pg.452]    [Pg.454]    [Pg.458]    [Pg.1325]   


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