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81.
Morphologic and immunohistochemical observations in granulomatous glomerulonephritis. 总被引:1,自引:0,他引:1
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D. B. Bhathena S. D. Migdal B. A. Julian R. G. McMorrow R. W. Baehler 《The American journal of pathology》1987,126(3):581-591
Eight renal biopsies of Wegener's granulomatosis and other vasculitic syndromes with periglomerular granulomatous reactions (granulomatous glomerulonephritis) are studied. Controls consist of 57 biopsies of crescentic and focal necrotizing glomerulonephritis (of various diseases, excluding systemic lupus erythematosus). Both groups have in common the morphologic alterations of inflammatory tuft necrosis, fibrin exudation into the urinary space, crescent formation, and breaks of Bowman's capsule. In the study group, the unique feature of glomeruli with surrounding granulomatous reactions was the presence, within the urinary space, of an exudate of fibrin mixed with immune reactants (immunoglobulins and usually complement) in association with gaps of Bowman's capsule. This contrasts with an exudate of fibrin alone in glomeruli of the control group and other glomeruli of the study group. The study group also had a significantly greater incidence of immune deposits in Bowman's capsule (P less than 0.001). Giant cells may result from the interaction of macrophages of the granuloma with Bowman's capsule that is permeated with immune reactants. 相似文献
82.
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84.
The attainment of adequate renal protection requires strict blood pressure control and a diminution of proteinuria or microalbuminuria
to values as near from normalcy as possible. It has been considered that by getting the first, the second could be attained
at the same price. Recent data have confirmed that renal protection in hypertensive patients, diabetics or not, requires combination
therapy that has to include an angiotensin converting enzyme inhibitor or an angiotensin receptor blocker. A calcium channel
blocker can be added to this without renal compromise. A diuretic will also be needed in most cases. Proteinuria will diminish
with this combination in particular if up-titration of the drug blocking the effects of angiotensin II is performed. The control
of other associated risk factors is also required, in particular smoking and lipids. 相似文献
85.
86.
There are advantages and disadvantages associated with utilization of online health services among individuals living with cancer. Accessing accurate, reliable health-related information online gives patients the power to enhance their understanding of information they obtain from their health care providers. However, online health information can often be confusing for patients to interpret, and it can sometimes be conflicting or incorrect. Based on a framework by Eysenbach, the following paper discusses various types of cancer services that are available online, and it addresses both positive and negative health outcomes that have been linked to utilizing such services. 相似文献
87.
Pincivero DM Coelho AJ Campy RM Salfetnikov Y Bright A 《European journal of applied physiology》2002,87(4-5):448-455
The purpose of this study was to examine the effect of voluntary contraction efforts on the median frequency (f
med) of the electromyogram (EMG) recorded from the quadriceps femoris muscle in healthy men and women. A group of 30 healthy
volunteers (15 men, 15 women) were assessed for EMG activity of the vastus medialis (VM), vastus lateralis (VL), and rectus
femoris (RF) muscles during isometric contractions with the knee at 60° flexion. Subjects performed a series of 5 s maximal
voluntary isometric contractions that anchored the perceptual range with a "10" on a 10-point scale. Sub-maximal isometric
contractions were then separately performed at the following perceived effort levels on the 10-point scale: 1, 2, 3, 4, 5,
6, 7, 8 and 9, in a random order. Subjects were instructed to maintain the contraction at each perceived level of effort for
5 s. The f
med of the three muscles was assessed using a power spectrum analysis performed over 11 consecutive, 512 ms, epochs overlapping
each other by half their length during the middle 3 s of each contraction. The f
med for each of the 11 epochs was then determined for each muscle, followed by calculation of the means and normalized coefficients
of variation [(standard deviation/mean)×100%] for each contraction. The results demonstrated that the mean f
med of VL was significantly greater than those of the other two muscles, and that f
med of RF was significantly greater than that of VM. The VL muscle demonstrated a significant increase in mean f
med across the contraction efforts, compared to the VM and RF muscles that displayed a significant decrease. The men displayed
significantly higher f
med values for the VM muscle than did the women, as well as showing a significantly greater increase across the contraction efforts
for the VL muscle. The variability of f
med was shown to be significantly higher for the VM muscle, compared to the VL and RF muscles. The findings of this study suggest
that the f
med statistic is most sensitive to contraction intensity efforts for the VL muscle, and that men display significantly higher
values for the VL and VM muscles, compared to women.
Electronic Publication 相似文献
88.
Detection of cytomegalovirus infection during a vaccine clinical trial in healthy young women: seroconversion and viral shedding. 总被引:3,自引:0,他引:3
Changpin Zhang Hannah Buchanan William Andrews Ashley Evans Robert F Pass 《Journal of clinical virology》2006,35(3):338-342
BACKGROUND: An antibody method based on absorption of serum with cytomegalovirus (CMV) glycoprotein B (gB) was developed for detection of infection during clinical trials of CMV gB vaccine. Previous study showed that this method detected the antibody response to infection and was negative with vaccine induced immunity. OBJECTIVES: In an ongoing efficacy trial of CMV gB vaccine the ability of the gB-absorbed CMV IgG assay to detect CMV infection was assessed and compared with viral culture results. STUDY DESIGN: Two hundred and ninety two healthy, seronegative young women in a phase II, double-blind, placebo-controlled, clinical trial of recombinant CMV gB vaccine (sanofi pasteur) with MF59 adjuvant (Chiron) were randomized to receive CMV gB vaccine or placebo (1:1) on a 0, 1 and 6 month schedule. Participants were screened every 3 months for CMV infection using the gB-absorbed CMV IgG assay, and a subgroup was also screened for infection with viral cultures. Viral culture (urine, vaginal swab and saliva) was used to confirm CMV infection in all subjects with a positive gB-absorbed CMV IgG result. RESULTS: Evidence of CMV infection (gB-absorbed CMV IgG levels>or=5.0 AU/ml) was found in 23/292 (7.88%) study participants. The gB-absorbed CMV IgG levels of their first positive serum ranged from 15.7 to 251.0 AU/ml with a mean of 77.0 AU/ml and a median of 44.9 AU/ml. Cytomegalovirus was isolated from all 23 of them from culture specimens collected after their first positive gB-absorbed CMV IgG. The time to first CMV positive culture from first positive gB-absorbed CMV IgG ranged from 0 to 12 weeks with a median of 2 weeks. CONCLUSIONS: The gB-absorbed CMV IgG assay detects CMV infection in CMV gB vaccine clinical trials earlier and more rapidly than virus culture and does not reveal whether subjects received CMV gB vaccine or placebo. 相似文献
89.
P. J. Griffiths J. J. Duchateau Y. Maeda J. D. Potter C. C. Ashley 《Pflügers Archiv : European journal of physiology》1990,415(5):554-565
Intact muscle fibres fromBalanus nubilus develop tensions of up to 600 kN sd m−2 during electrical stimulation. The rise of tension occurs with a half-time (177 ms at 12° C) about fivefold longer than that
of tetanised frog muscle at the same temperature. The response of myofibrillar bundles to a rapid stretch resembles that of
frog muscle but has a yo value (i.e. the size of an instantaneous release necessary to just discharge tension) which is ca. 2.5 times smaller, and
phase 2 of the tension transient (the “quick phase”) occurs at a rate comparable to that of frog muscle. In contrast, the
ATPase activity (0.018 mmoles · kg wet weight−1 · s−1) of this preparation and its maximum shortening velocity (0.15–0.16 muscle lengths · s−1) are both at least fivefold slower than frog muscle. These findings can be accounted for by a cross-bridge cycle in barnacle
muscle in which events prior and subsequent to the tension generating step(s) occur at a rate at least fivefold slower than
comparable steps in frog muscle, but the step(s) associated with tension development occur at similar rates in the two preparations.
Since the rate of mechanical relaxation in barnacle muscle is modified in the presence of intracellular calcium buffers and
by depolarisation-induced elevation of the free calcium during the relaxation phase, it is proposed that the time course of
relaxation is not determined exclusively by the kinetics of the cross-bridge cycle, but is also dependent on the free calcium
concentration during relaxation. 相似文献
90.
Malyak Mark Smith Michael F. Abel Ashley A. Arend William P. 《Journal of clinical immunology》1994,14(1):20-30
Journal of Clinical Immunology - The objective of this study was to characterize interleukin-1 receptor antagonist (IL-1ra) and interleukin-1β (IL-1β) production by human peripheral blood... 相似文献