Ventral surface

The thyroid gland is a butterfly-shaped structure lying over the ventral surface of the trachea just below the larynx. This gland produces two classes of hormones synthesized by two distinct cell types ... 

The central chemoreceptors are located near the ventral surface of the medulla in close proximity to the respiratory center. These receptors are surrounded by the extracellular fluid (ECF) of the brain and respond to changes in H+ ion concentration. The composition of the ECF surrounding the central chemoreceptors is determined by the cerebrospinal fluid (CSF), local blood flow, and local metabolism. 

The ventral subgroup, situated at the ventral surface of the brain, rostral and caudal to the mammillary bodies, is the largest subgroup, containing approximately 2500 neurons (Kohler et a ., 1985). The ventral subgroup has fewer parvicellular neurons than the medial subgroup. 

Fig. 5. Three views of the NCP from Harp et al. [31]. (a) Ventral surface view, (b) Side view, (c) View down the molecular pseudo-dyad axis. The histones are represented by Ca ribbon models of the secondary structure elements, and the DNA model indicates the base pairing between complementary strands. The DNA is positioned asymmetrically by one-half base pair on the NCP. This results in a two sides arbitrarily referred to a dorsal and ventral (the surface shown here). The ventral surface of the NCP is best recognized by the extended N-terminal H3 tail protruding to the right. In these images, the pseudo-dyad axis is represented by vertical bars for both the ventral and side view. The pseudo-dyad axis passes through the center of the dyad view orthogonal to the plane of the page, (d) Color code for histone chains in the figures in this chapter. Note the change in hue denoting the two sides of the histone octamer.

Fig. 9. Accessory helices in core histone structures, (a) Accessory H3 helix, shown in a ribbon Ca model, interacts with the DNA entering and leave the nucleosome. A short helix in the tail of H2A is seen between the accessory and medial helix of H3. (b) Solvent accessible surface representation of the C-terminal residues of H2A showing the contribution of these residues to the ventral surface of the NCP.

Fig. 18. TLS analysis of the palindromic DNA on the NCP. (a) Composite motions of the DNA gyres looking at the ventral surface with the DNA colored by atom type. The two gyres reflect the structural asymmetry of the NCP with non-coincident axes of motion and different orientations for the primary axis of motion. The ventral gyre TLS axes more closely resemble the composite motions of the individual H3 H4 dimers (Fig. 17c), the dorsal TLS axes resemble the composite motion of the tetramer. (b) The composite motions of the DNA gyres are shown in a view down the dyad axis. The DNA is shown in a surface representation colored by atom type. Note that axes of motion appear parallel and in plane with the pitch of the DNA. In this view the ventral surface is on the bottom of the image.

Only ventral surface ciliated internal jaws absent.Phylum Gastrotricha... 

DorsivenTRAL Being flattened so that there are distinct dorsal and ventral surfaces. 

Fig. 17.2. a Superficial arteries of the spinal cord. X-ray film of an injected specimen in a.p. view. The anterior spinal artery system is visible on the ventral surface of the cord, b Intrinsic spinal cord arteries. X-ray microangiogram of a transverse section (lumbar enlargement). The sulcal or central artery within the anterior fissure (arrow) is dominant. Note the posterior and posterolateral spinal arteries at both sides of the posterior root entry zone (arrowheads). AST, anterior spinal artery... 

Column 2 Represents the daily dose for 14 days of a selected experimental agent applied onto a region between the two cartilage ridges of the ventral surface of left pinna. 

Activity of the inhibitors in vivo was assayed as described in Feyereisen et al. (30). The compounds were topically applied to the ventral surface of the thorax in 2 pi of acetone. Adult mated females were treated on day 2 and the length of the terminal oocytes was measured on day 5. Seven to 20 insects were used for each dose of inhibitor. Growth of the oocytes during that period was compared to the growth of oocytes from control insects treated with acetone alone. In some experiments the insects were treated sequentially with inhibitor and 200 pg hydroprene (ZR512) on day 2. 

In 10 stable patients maintained on methadone (50-120 mg/day) and nine healthy subjects assessed using polysomnography, the methadone-maintained patients had more abnormalities of sleep architecture, with a higher prevalence of central sleep apnea (23). Methadone depresses respiration, probably by acting on p opioid receptors in the ventral surface of the medulla and possibly on other receptor sites in the lung and spinal cord. All the patients taking methadone also used benzodiazepines and cannabis, which may have influenced the above findings. 

Extent of Damage to Mucosal Cells. Permeation enhancement implies possible alteration of the protective permeability barrier either by 1) an increase in the fludity of intercellular lipids (relatively non-toxic) and/ or 2) extraction of intercellular lipids or denaturation of cellular proteins (much more damaging/toxic). Therefore, it is imperative that the permeation enhancer 1) exert a reversible effect 2) not be systemically absorbed and 3) not cause cumulative toxicity or permanent changes in the barrier properties. Application of up to 1% sodium lauryl sulfate or cetylpyridinium chloride to the ventral surface of the tongue of dogs resulted in desquamation, widening and separation of keratin.f The buccal mucosa of rabbits treated with... 

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