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Danger differentiation

Cytokines, eg, interferons, interleukins, tumor necrosis factor (TNF), and certain growth factors, could have antitumor activity directiy, or may modulate cellular mechanisms of antitumor activity (2). Cytokines may be used to influence the proliferation and differentiation of T-ceUs, B-ceUs, macrophage—monocyte, myeloid, or other hematopoietic cells. Alternatively, the induction of interferon release may represent an important approach for synthetic—medicinal chemistry, to search for effective antiinflammatory and antifibrotic agents. Inducers of interferon release may also be useful for lepromatous leprosy and chronic granulomatous disease. The potential cytokine and cytokine-related therapeutic approaches to treatment of disease are summarized in Table 4. A combination of cytokines is a feasible modaUty for treatment of immunologically related diseases however, there are dangers inherent in such an approach, as shown by the induction of lethal disserninated intravascular coagulation in mice adrninistered TNF-a and IFN-y. [Pg.41]

U-Tube U-Bundle Only one tube sheet required. Tubes bent in U-shape. Bundle is removable. High temperature differentials which might require provision for expansion in fixed tube units. Clean service or easily cleaned conditions on both tube side and shell side. Horizontal or vertical. Bends must be carefully made or mechanical damage and danger of rupture can result. Tube side velocities can cause erosion of inside of bends. Fluid should be free of suspended particles. 1.08... [Pg.25]

The measurement being differential, the noise which in uncorrelated between both arms is much more dangerous than correlated noise. [Pg.316]

In mobile phase (a), the two compounds have virtually identical k values and if a single response were to be measured with a k value of 4.86 it would not be possible to say, nneqnivocally, which, if either, of these analytes was present. In mobile phase (b), the k of vinbarbitone has changed to a significantly greater extent than that of secbutobarbitone. This change wonld allow these two compounds to be differentiated, although an uneqnivocal identification on these limited data would still be dangerous. [Pg.39]

In addition to these standardised test methods set by regulation (in particular the transport regulations of dangerous substances), there are laboratory methods that can provide more details regarding substance behaviour. In particular, there is differential thermal analysis (DTA), thermal gravimetric analysis, calorimetry and thermomanometry, which will not be described here. [Pg.96]

Possible dangerous increase in NH3 concentration measure and log pressure differential Impurities, possible poisoning of catalyst proper maintenance... [Pg.387]

An analysis of more than 130 preclinical candidates that had attrited during further development showed the failure of the chemotype approach (i.e. that a compound of the same/similar chemotype will have similar risks of attrition and that a structurally diverse chemotype will offer the best approach to minimize attrition risk) and 2D structure-based methods to be able to effectively differentiate compounds [29]. Thus, the risk of failing or succeeding in development is not related to being of the same chemotype , and differentiation by this method may not be the most effective way dangers are both that a valuable series/chemotype could be discarded because of one bad result and that a structurally different compound may actually have similar off-target effects (e.g. due to the decoration versus the scaffold). [Pg.36]

Many of the chemicals listed are extremely toxic and dangerous. No attempt has been made to differentiate between dangerous and safe chemicals. Unless you have knowledge to the contrary, you should assume that all chemicals are dangerous. [Pg.4]

It must always be remembered that optimisation is not an exact science and, therefore, it is sometimes difficult to define confidence limits in the final optimised values for the coefficients used in the thermodynamic models. The final outcome is at least dependent on the number of experimental measurements, their accuracy and the ability to differentiate between random and systematic errors. Concepts of quality can, therefore, be difficult to define. It is the author s experience that it is quite possible to have at least two versions of an optimised diagram with quite different underlying thermodynamic properties. This may be because only experimental enthalpy data were available and different entropy fiinctions were chosen for the different phases. Also one of the versions may have rejected certain experimental measurements which the other version accepted. This emphasises the fact that judgement plays a vital role in the optimisation process and the use of optimising codes as black boxes is dangerous. [Pg.311]

The usual experimental criterion for diffusion control involves an evaluation of the rate of reaction as a function of particle size. At a sufficiently small particle size, the measured rate of reaction will become independent of particle size. The reaction rate can then be safely assumed to be independent of intraparticle mass transfer effects. At the other extreme, if the observed rate is inversely proportional to particle size, the reaction is strongly influenced by intraparticle diffusion. For a reaction whose rate is inhibited by the presence of products, there is an attendant danger of misinterpreting experimental results obtained for different particle sizes when a differential reactor is used, because, under these conditions, the effectiveness factor is sensitive to changes in the partial pressure of product. [Pg.164]

The inner counter cylinder, made of metallized Mylar foil, is leak-tight relative to the outer counter. By means of two solenoid valves actuated by a differential mercury manometer, the outer and inner counters can be filled separately with a pressure differential on the partitioning foil of less than 0.5 cm. Hg. This pressure controller minimizes the danger of rupturing the partition. Two control circuit diagrams are shown in Figure 3. Figure 3A shows the mercury tube with electrical... [Pg.184]

The behavior of VACF and of D in one-dimensional systems are, therefore, of special interest. The transverse current mode of course does not exist here, and the decay of the longitudinal current mode (related to the dynamic structure factor by a trivial time differentiation) is sufficiently fast to preclude the existence of any "dangerous" long-time tail. Actually, Jepsen [181] was the first to derive die closed-form expression for the VACF and the diffusion coeffident for hard rods. His study showed that in the long time VACF decays as 1/f3, in contrast to the t d 2 dependence reported for the two and three dimensions. Lebowitz and Percus [182] studied the short-time behavior of VACF and made an exponential approximation for VACF [i.e, Cv(f) = e 2 ], for the short times. Haus and Raveche [183] carried out the extensive molecular dynamic simulations to study relaxation of an initially ordered array in one dimension. This study also investigated the 1/f3 behavior of VACF. However, none of the above studies provides a physical explanation of the 1/f3 dependence of VACF at long times, of the type that exists for two and three dimensions. [Pg.204]


See other pages where Danger differentiation is mentioned: [Pg.703]    [Pg.109]    [Pg.238]    [Pg.147]    [Pg.14]    [Pg.25]    [Pg.486]    [Pg.1067]    [Pg.1114]    [Pg.537]    [Pg.390]    [Pg.88]    [Pg.250]    [Pg.20]    [Pg.189]    [Pg.165]    [Pg.504]    [Pg.104]    [Pg.99]    [Pg.205]    [Pg.16]    [Pg.279]    [Pg.517]    [Pg.519]    [Pg.535]    [Pg.12]    [Pg.142]    [Pg.32]    [Pg.127]    [Pg.62]    [Pg.147]    [Pg.57]    [Pg.530]    [Pg.194]    [Pg.776]    [Pg.14]    [Pg.153]   
See also in sourсe #XX -- [ Pg.37 ]




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