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The efficacy of an early and late treatment with the angiotensin converting enzyme inhibitor lisinopril or the angiotensin II receptor blocker ICI D8731 was investigated in uninephrectomized spontaneously hypertensive rats (SHR). Rats that underwent uninephrectomy (UNX) at six weeks of age were randomly assigned to receive no treatment, lisinopril shortly after UNX, lisinopril starting 16 weeks after UNX, ICI D8731 shortly after UNX, and ICI D8731 starting 16 weeks after UNX. Blood pressure was normalized with both treatments. After six months inulin clearance was not significant different, while proteinuria and prevalence of interstitial fibrosis were significantly reduced in all treatment groups. Immunohistochemical studies revealed an interstitial, periglomerular and perivascular increase of extracellular matrix proteins in all rats, but a markedly reduced expression of collagen I, IV and fibronectin after early and late treatment compared to untreated controls. We found a significant reduction of infiltrating macrophages and T-lymphocytes in all treated animals compared to untreated controls after 2, 4 and 6 months. Especially early treatment was associated with lower numbers of infiltrating cells. Both treatments reduced proliferation of tubular and interstitial cells. There were no striking differences with regard to nephroprotection between the ACE inhibitor and angiotensin II receptor blocker. These findings show that both treatments have beneficial effects on kidney structure and function. They suggest that both ACE inhibition and angiotensin II blockade decrease renal cell proliferation and suppress the infiltration of mononuclear cells that may trigger expression of extracellular matrix proteins and progressive nephrosclerosis.  相似文献   
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The statistical properties of an image of an EM support film could be completely specified by evaluating all orders of joint probabilities of the image optical density values. The probability of random fluctuations in the support image interfering with the identification of images of atoms at the vertices of an n-sided polygon can be determined from the nth order statistics. This probability has been calculated as a function of the OD at specified points, for n= 1, 2 and 3. The first order statistics amount to the probability of finding a particular OD in the image, where the width of the distribution gives the standard deviation of the OD values, or contrast. The second order statistics or covariance (correlation) function provide an intuitive understanding of the granularity of the image. We have measured the first and second order statistics of carbon and aluminum oxide films imaged under a variety of conditions, and have found them useful in quantitative assessment and comparison of the images. The lower contrast of the aluminum oxide films is reflected in both the OD distribution and covariance function. The contrast of both types of films is found to be a non-monotonic function of film thickness.  相似文献   
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We have studied the performance of scintillating glass fiber-optic plates using 10 GeV/c particles at the SLAC test beam. The plates were composed of: (1) Terbium activated cladded-glass cores in a matrix of 15 ?m spacing; and (2) Cerium activated cladded-glass cores in a matrix of variable spacing 6-10 ?m. The target plates were viewed with a three-stage, gatable image intensifier. Particle tracks and nuclear interactions were recorded on film for both materials. We observe 5 detected hits/mm for minimum ionizing particles for the Tb glass, and 1-2 hits/mm for the Ce glass. The test results indicate that scintillating glass fiber-optic plates can be used as high spatial resolution tracking detectors for both fixed target and colliding beam experiments.  相似文献   
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We have studied the performance of a scintillating glass fiber-optic plate with minimum ionizing particles. The target is composed of terbium activated cladded-glass cores in a matrix of 25 ?m spacing. The plate was viewed by a three-stage, electrostatically focussed image intensifier. Particle tracks were observed with a width consistent with the resolution of the device. Details of the detection system and future developments are discussed.  相似文献   
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The extended V-Y flap, a modified V-Y advancement flap, is very useful in closing relatively large defects on the face. Its extension limb is hinged down as a transposition flap on the end of the V-Y advancement flap to close the most distal portion of the defect. We applied this flap in closing a defect following excision of skin tumors on the face with excellent cosmetic results in 11 patients. However, this flap tended to make a distortion at the base of the flap in the primary closure site. By drawing figures, we concluded that the distortion was due to the characteristic of this technique as a V-Y advancement-rotation flap or V-Y advancement flap with rotation.  相似文献   
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