Resistance human body

It is observed that the body s resistance diminishes at higher voltages, above 1 kV and currents more than I A, passing through the body, due to a puncture of the skin tissues. For all safety measures and ground design consideration, the average human body resistance is considered universally, as 1000 Q which has yielded satisfactory results. 

The product is destined to be used in die case of die pari al faults no matta viiere they are localized ( stem, antero-lateral thoracic wall, post ior sci ular thoracic wall etc.) and what is the size of the fimlt The product vriiidi, by its geometrical, technical, biofunctional and biomedical characteristics has to meet the inqiosed leqiurements, such as -adaptability to any duqie and rize of the ult -malleability -human bodies - resistance to infections -radio transparency. 

The proportion of the leakage current through a human body will depend upon the resistance of the body... 

To determine the total resistance of the ground circuit through the human body, the following may be adopted. 

Body mass The mass of the unclothed human body in kg, which is a measure of its inertia, or resistance to any alteration in its motion. The mass of a given body is the same anywhere on the earth or in space. 

Plastic s main disadvantages are its lower scratch resistance and, in some systems, comparative intolerance to severe temperature fluctuations. Even if plastic does have less temperature tolerance than glass, most optical systems do not operate in ambient temperatures beyond the thermal limits of plastics or the human body. 

Silicone They have excellent heat resistance up to 260°C (500°F), chemical resistance, good electricals, compatible with human body tissues, etc. and a high cost. There are the room temperature vulcanizing (RTV) types that cure and cross-link at ambient temperatures, catalyzed by moisture in the air. It is a good sealant and excellent for making flexible molds for casting. It is widely used for human implants. 

In order to be successful as part of a medical device a polymer has to resist both biological rejection by the patient s body and degradation. The human body is an enviromnent which is simultaneously hostile and sensitive, so that materials for application in medicine must be carefully selected. The essential requirement is that these materials are biocompafible with the particular part of the body in which they are placed. The extent to which polymers fulfil this requirement of biocompafibility depends partly on the properties of the polymer and partly on the location in which they are expected to perform. For example the requirements for blood biocompafibility are stringent since blood coagulation may be triggered by a variety of materials. By contrast, the requirements for materials to be used in replacement joints in orthopaedic surgery are less severe and materials as diverse as poly (methyl methacrylate) and stainless steel can be used with minimal adverse reaction from the body. 

The antioxidant activities of carotenoids and other phytochemicals in the human body can be measured, or at least estimated, by a variety of techniques, in vitro, in vivo or ex vivo (Krinsky, 2001). Many studies describe the use of ex vivo methods to measure the oxidisability of low-density lipoprotein (LDL) particles after dietary intervention with carotene-rich foods. However, the difficulty with this approach is that complex plant foods usually also contain other carotenoids, ascorbate, flavonoids, and other compounds that have antioxidant activity, and it is difficult to attribute the results to any particular class of compounds. One study, in which subjects were given additional fruits and vegetables, demonstrated an increase in the resistance of LDL to oxidation (Hininger et al., 1997), but two other showed no effect (Chopra et al, 1996 van het Hof et al., 1999). These differing outcomes may have been due to systematic differences in the experimental protocols or in the populations studied (Krinsky, 2001), but the results do indicate the complexity of the problem, and the hazards of generalising too readily about the putative benefits of dietary antioxidants. 

Tantalum is almost as chemically inert at room temperatures (it has the ability to resist chemical attacks, including hydrofluoric acid) as are platinum and gold. It is often substituted for the more expensive metal platinum, and its inertness makes it suitable for constructing dental and surgical instruments and artificial joints in the human body. 

A dose of 1 at 30 mg/kg increased the effects of intravenous doses of epinephrine at 5 g/kg and of dl-noreplnephrine at 10 ug/kg on both blood flow and blood pressure. Intravenous phenoxybenzamine at 15 mg/kg plus tolazollne at 2 mg/kg prevented almost completely the actions of I on blood pressure and blood flow Intravenous reserpine at 2 mg/kg increased markedly the effects of I at 30 mg/kg on blood pressure and peripheral resistance, but converted the usual immediate, small, temporary increase in blood flow into an immediate, small, temporary decrease. These various responses would be expected from either a mild sympathomimetic amine or an inhibitor of the breakdown of endogenous catecholamines Indeed, I at 10 M, was found to inhibit the monoamlneoxldase of the rat s liver. If the dose of I used in these experiments were distributed into the same fraction of the body water as that estimated for the human body,the concentration in the plasma would be about 9 times that stated above as the effective concentration for inhibiting the mono amine oxIdase. It is possible that inhibition of monoamlneoxldase by I plays a part in inducing the effects of the oxime on blood vessels and blood pressure. It is possible also that I interferes with reuptake of catecholamines by nerve endings this possibility seems not to have been explored. 

The helium supply seemed secure, but then scientists discovered a whole new application for the gas. Helium boils at the lowest temperature of any substance (-269°C) and it never solidifies. Liquid helium is therefore the ideal substance to cool electrical wires and reduce their resistance to the flow of the current. It has allowed us to manufacture superconducting magnets, which have diverse applications, but probably none more useful than in magnetic resonance imaging. This technology affords doctors a noninvasive look inside the human body, and it Is probably the most important medical diagnostic tool ever developed. The future of mri, however, hinges on the availability of helium. Think about that the next time you fill those birthday balloons with the gas. 

Resistance measured between two yarn electrodes implemented in an electrochemical cell positioned at the leg of a human body as a function of time. Sweat formation rate for (1) a diabetes patient at the moment of low sugar level, (2) an athlete exercising and (3) a diabetes patient walking in hot severe conditions arrow indicates the point at which the sugar level becomes low. 

The skin represents the largest organ in the human body, and one of its primary functions can be seen as a physical barrier to absorption of toxicants. The other major routes of toxicant entry into the body are through the respiratory and gastrointestinal tract, which can be seen to offer less resistance to toxicant absorption than the skin. In general, the respiratory tract offers the most rapid route of entry, and the dermal the least rapid. One reason for this major difference is primarily because membrane thickness, which is really the physical distance between the external environment (skin surface, air in the lung, or lumen of the gut) and the blood capillaries, varies across these portals of entry. The overall entry depends on both the amount present and the saturability of the transport processes involved. 

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