Excretory phase

Fig. 74. Delayed CT in apatient with ALPE and a patient with myoglobinuric acute renal failure with a serum creatinine level of 1.5mg/dl. In the patient with ALPE, wedge-shaped contrast enhancement was observed 24 h after the administration of a contrast medium. However, wedge-shaped contrast enhancement could not be confirmed in the cortical phase 20-40 s after the administration, or in the excretory phase 3 min after the administration (see Fig. 17). The patient with myoglobinuric acute renal failure showed diffuse contrast enhancement...

Detailed studies have shown that norethandrolone affects both the uptake and excretory phases of BSP disposal (L6) and the plasma contains more conjugated BSP (S8). In high dosage (100-150 mg daily), this drug reduces the storage capacity of the liver for BSP as well as the maximal transport rate (L6), but at lower dosage (20 mg daily) the stor-... 

The 16-detector row CTU protocol is as follows for the unenhanced scan, the abdomen and pelvis are imaged by using 1.5-mm collimation with a pitch of 0.875, 120 kVp, and 160-280 mA. The kidneys are scanned 30 and 90-100 s after intravenous administration of 130-160 ml of contrast medium at a rate of at least 3 ml/s by using the same parameters. The entire abdomen is scanned during the excretory phase, 5-6 min after the contrast medium is injected, by using 0.75-mm collimation, a pitch of 0.82-1.00,120 kVp, and 160-280 mA. 

Fig.23.1. SSD coronal oblique image in the excretory phase of multidetector CT demonstrates dilation of cali-ces and pelvis in the left kidney due to a stenosis of the ureteropelvic junction...

Fig. 23.3a-c. Coronal MIP (a) and coronal oblique MIP (b,c) images in the excretory phase of CTU show a partially duplicated right renal collecting system and a completely duplicated left collecting system... 

In trauma of the kidney, excretory-phase imaging after 3 to 10 min can provide valuable information about the extent of the injury into the renal collection system (Fig. 42.3) (Park et al. 2006). When injuries to the spleen and liver are present, late-phase images help to plan interventions because they allow differentiating pseudoaneurysms from lacerations and active contrast material extravasations (Marmery and Shanmuganathan 2006). 

CT has always played a minor role in kidney transplant imaging because it requires normal renal function for analysis of the renal parenchyma or renal vessels. However, the dose of iodine contrast medium now required with MDCT is lower, making it possible to broaden its indications. Association of early acquisitions, during the arterial phase, and late acquisitions, during the excretory phase, provides complete information about the graft (Sebastia et al. 2001). 

The second phase of metabolism consists of synthetic reactions that convert active compounds into inactive excretory products. Drugs that contain suitable chemical groups, such as —OH, —NHa, or —COOH, can undergo these synthetic conjugation reactions if not present in the parent compound, such drugs may be introduced during phase one reactions. Phase one and phase two metabolic reactions occur sequentially. 

Giebultowicz JM, Stanewsky R, Hall JC, Hege DM 2000 Transplanted Drosophila excretory tubules maintain circadian clock cycling out of phase with the host. Curr Biol 10 ... 

Auricchio et al. (A9-A11) analyzed the excretory pattern of tryptophan metabolites in urine of 10 normal newborn children from the first to 30th day of life. During the period 1st day to 4th-llth day no tryptophan metabolites were detected. During a second phase, 5th-12th day until 7th-28th day, several metabolites together with their conjugates were... 

Demers, et al [137] described the observation of pretibial edema and sodium retention in lithium treated patients, in the absence of clear evidence of renal, hepatic or cardiac disease. The mechanism for such fluid retention remains unclear, but two plausible mechanisms have been suggested an excessive sodium intake, perhaps related to the manic phase and a lithium-induced reduction in maximum sodium excretory capacity which tends to be negligible when sodium intake is normal. Such patients manifested varying degrees of edema, combined with significantly increased urinary sodium > 200 mEqs/ day. Furthermore, due to increased urinary excretion of lithium, actual serum lithium levels may fall below therapeutic ranges, thereby leading to precipitation of manic crises. As volume expands, there is decreased reabsorption of sodium in the proximal tubules similarly, since hthium is reabsorbed via the same channels and transporters as sodium, lithium reabsorption also decreases [11]. 

Skin repair after a peel to the reticular dermis is slower, as all the basal layer keratinocytes have been destroyed and the skin can only rely on the differentiated keratinocytes of the pilosebaceous units and the intradermal excretory ducts of the sweat glands. To repair the dermis, the sebocytes in the pilosebaceous units must dedifferentiate, and horizontal growth is required to close the skin quickly. Next comes a phase of vertical growth whose purpose is to regenerate a physiologically sound epidermis that will maintain homeostasis and restore the vital barrier function after the keratinocytes have differentiated into corneocytes. 

In rabbits with one kidney-one clip hypertension, treatment with indomethacin for 10 days aggravates the hypertension and causes deterioration of renal haemodynamic and excretory functions, while reducing plasma renin activity . In contrast, short-term treatment with indomethacin was reported to reduce both blood pressure and plasma renin activity in dogs with one kidney-one clip hypertension . Treatment with meclofenamate prior to and following bilateral renal artery constriction markedly attenuates, in the acute phase, the development of hypertension in rats. However, once the... 

There are many similarities between human essential hypertension and experimental renal hypertension. To mention a few In both cases cardiac rate and output, blood volume, and blood viscosity, as well as peripheral blood flow, are normal. Renal blood flow seems to be reduced, while renal excretory function remains normal in the benign phase of both the human and the experimental disease and becomes reduced in the malignant phase. In both types of hypertension cardiac hypertrophy occurs and is chiefly left ventricular. 

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