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21.
In a previous study in conscious spontaneously hypertensive rats (SHR), we observed an immediate decrease in the cardiac index (CI) and an increase in the total peripheral resistance index (TPRI) following the administration of furosemide. The present study was designed to evaluate the regional hemodynamic effects and the involvement of sinoaortic baroreceptors in the increase in TPRI. In SHR instrumented for the measurement of central hemodynamics, 8 mg.kg-1 furosemide decreased CI from 31.0 +/- 2.5 ml.min-1.100 g bw-1 by 9.5 +/- 1.3 ml.min-1.100 g bw-1 (n = 7). TPRI increased maximally from 5.7 +/- 0.8 by 2.7 +/- 0.5 mm Hg.min.100 g bw.ml-1. The effect on TPRI was not affected by sinoaortic denervation (SAD) to abolish arterial baroreflexes. However, furosemide induced a significantly greater decrease in CI (-12.6 +/- 1.2 ml.min-1.100 g bw-1; n = 7) after SAD. Furosemide effectively reduced the mean arterial pressure in SAD SHR (-21 +/- 9 mm Hg) but not in sham-denervated SHR. Furosemide (8 mg.kg-1) reduced renal, mesenteric and hindquarter blood flow to a comparable extent (approximately 20%) in intact SHR. The reduction in renal flow at 3.5 min after injection (-17.9 +/- 4.1%; n = 8) was significantly greater than the reduction in mesenteric (-7.1 +/- 4.7%) and hindquarter blood flow (-4.2 +/- 3.7%), suggesting that the renal bed responds faster. Thereafter, the flow reductions in the three beds were not different. The results show that furosemide causes a general vasoconstriction in conscious SHR.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
22.
Kupffer cell depletion in vivo results in clearance of large-sized IgA aggregates in rats by liver endothelial cells. 总被引:3,自引:1,他引:2
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W M Bogers R K Stad D J Janssen F A Prins N van Rooijen L A van Es M R Daha 《Clinical and experimental immunology》1991,85(1):128-136
We investigated the clearance kinetics and tissue distribution of different sized IgA in normal and macrophage-depleted rats. Rats were injected iv with liposomes containing dichloromethylene diphosphonate (DMDP). DMDP treatment resulted in complete depletion of liver macrophages 24-48 h after administration. Normal and macrophage depleted rats were injected intravenously with monomeric, dimeric, polymeric or aggregated polymeric IgA (AIgA) and assessed for blood clearance and tissue distribution. In normal rats, clearance of IgA was size dependent, i.e. a faster clearance with increasing size. No differences in clearance kinetics were observed of the different sized IgA between normal and DMDP-treated rats. TCA non-precipitable radioactivity, a measure for degradation of IgA, was found in the circulation of normal and DMDP-treated rats after AIgA administration. The liver was the main organ responsible for the clearance of IgA in normal and DMDP-treated rats. Immunofluorescence studies on liver biopsies indicated that AIgA was associated with Kupffer cells in normal rats. Electron microscopical studies revealed that the AIgA was internalized and located in vesicles in Kupffer cells. In DMDP-treated rats the AIgA was associated with endothelial cells and electron microscopy studies showed that this AIgA was taken up by endothelial cells. These data show that rat liver endothelial cells are able to bind, internalize and degrade AIgA in situations where Kupffer cells are absent, and that these cells may play an important role in the handling of AIgA and IgA-immune complexes. 相似文献
23.
Nowadays, endocrine problems like retarded sexual maturation and growth deficiency, lead to substantial suffering in patients with beta-thalassemia major. The aim of the present study is the differentiation between a possible insufficiency of the pituitary gland and dependent target organs, respectively. 12 patients (age 1.9-18.10 years) were examined by means of a combined pituitary function test. The corticotropic axis turned out to be normal as shown by a regular stimulation of cortisol in all patients tested. The thyrotropic function was unaffected in all children: elevated levels of TSH pointed to primary hypothyroidism. Pubertal values of LH and FSH were found in only 3 out of 7 patients at pubertal age. In 10 out of 12 children, stimulation led to a rise in STH levels above 10 ng/ml. On the whole, there was no evidence for pituitary insufficiency in beta-thalassemia major. 相似文献
24.
Elevated body mass index and mortality risk in the elderly 总被引:2,自引:0,他引:2
The purpose of this report was to perform a systematic review and meta-analysis of the studies examining the impact of an elevated body mass index (BMI) on mortality risk in elderly (> or =65 years) men and women. A variance-based method of meta-analysis was used to summarize the relationships from available studies. The summary relative risk of all-cause mortality from the 26 analyses that included a risk estimate for a BMI within the overweight range was 1.00 (95% confidence intervals, 0.97-1.03). The summary relative risk of all-cause mortality for the 28 analyses that included a risk estimate for a BMI within the obese range was 1.10 (1.06-1.13). These calculations indicate that a BMI in the overweight range is not associated with a significantly increased risk of mortality in the elderly, while a BMI in the moderately obese range is only associated with a modest increase in mortality risk. 相似文献
25.
Two cases of gouty tenosynovitis were associated with carpal tunnel syndrome. Both patients had carpal tunnel release with good relief of symptoms. In one patient, gout was not suspected before operation; this patient developed wound dehiscence with tophaceous urate crystal drainage that eventually disappeared. Proper preoperative antigout therapy may have prevented this complication. Carpal tunnel syndrome associated with gout is rare. Preoperative investigations for gout may be indicated in patients with carpal tunnel syndrome. 相似文献
26.
Spontaneous remission in a patient with therapy-related myelodysplastic syndrome (t-MDS) with monosomy 7 总被引:1,自引:0,他引:1
B. Renneboog V. Hansen P. Heimann A. De Mulder F. Janssen & A. Ferster 《British journal of haematology》1996,92(3):696-698
We describe a case of spontaneously reversible refractory anaemia, a subtype of myelodysplastic syndrome (MDS), with monosomy 7 secondary to chronic treatment with azathioprine (AZA) in a young renal transplant recipient. AZA was stopped after that conventional cytogenetics and fluorescence in situ hybridization (FISH) had demonstrated the existence of a monosomy 7 clone. 4 months later, haematological values had considerably improved and the karyotypic examination as well as the FISH analysis were normal. The spontaneous remission of this MDS with monosomy 7, which is usually associated with a particularly poor prognosis, could be due to the recovery of a better immunosurveillance following the withdrawal of AZA. 相似文献
27.
Summary Fourteen patients with Ph'-chromosome positive chronic myelogenous leukemia (CML) in first chronic phase were treated with recombinant interferon-2c. Interferon-2c 5 to 10×106 units s.c. was given for 12 weeks as an induction therapy. Maintenance treatment consisted of interferon-2c 5 × 106 units twice weekly s.c.. Two patients (14%) attained a complete clinical remission and 6 (43%) a partial remission, 3 of whom developed progressive disease during maintenance therapy. A complete disappearance of Ph'-chromosome was achieved in 1 patient. All patients had a more than 45% initial decline of the leukocyte count. Four out of ten patients with an initially enlarged spleen demonstrated reduction in spleen size. Influenza-like symptoms, anorexia, nausea, weight loss and fatigue were common side effects. Interferon-alpha is active in CML but additional clinical investigations are warranted to assess more precisely the therapeutic value of the interferons in this disease. 相似文献
28.
HIV seroincidence among patients at clinics for sexually transmitted diseases in nine cities in the United States 总被引:1,自引:0,他引:1
Weinstock H Dale M Gwinn M Satten GA Kothe D Mei J Royalty J Linley L Fridlund C Parekh B Rawal BD Busch MP Janssen RS 《Journal of acquired immune deficiency syndromes (1999)》2002,29(5):478-483
Although the numbers of newly reported diagnoses of AIDS decreased in the 1990s, it is not clear whether they reflect a decreasing number of new HIV infections. Direct measurement of HIV incidence through follow-up cohort studies is difficult and costly. We estimated HIV incidence and trends in incidence among men who have sex with men (MSM) and heterosexual men and women at clinics for sexually transmitted diseases (STDs) by using a recently developed serologic testing algorithm that requires only a single blood specimen. Cross-sectional anonymous serosurveys were conducted at 13 STD clinics in nine cities in the United States from 1991 through 1997. Before anonymous HIV testing, demographic and clinical information was abstracted. Of 129,774 specimens tested, 362 (0.28%) were from persons estimated to be recently infected. Incidence among MSM was 7.1% (95% confidence interval (CI): 4.8-10.3), 14 times higher than that among heterosexuals, which was 0.5% (CI: 0.4- 0.7). Incidence among MSM and heterosexuals remained unchanged during the time studied. Decreasing rates of new AIDS diagnoses in the 1990s do not reflect stable rates of new HIV infections among MSM and heterosexual patients attending these clinics. 相似文献
29.
30.
van der Graaf M Janssen SW van Asten JJ Hermus AR Sweep CG Pikkemaat JA Martens GJ Heerschap A 《NMR in biomedicine》2004,17(6):405-410
Localized in vivo 1H magnetic resonance spectroscopy (MRS) was used to investigate metabolite levels in the brain of adult Zucker Diabetic Fatty (ZDF) rats, an animal model for type 2 diabetes mellitus. This study focussed on the hippocampus, assumed to be one of the main brain areas affected by this disease. Together with an almost 5-fold increase in blood glucose concentration measured by glucose oxidation, significant increases were found in the hippocampal concentrations of glucose (4.93 vs 1.66 mM p < 0.001), myo-inositol (6.52 vs 4.30 mM; p < 0.05), and total creatine (12.71 vs 10.50 mM; p < 0.05) in ZDF rats (n = 5) compared with littermates (n = 5). Although no obvious alterations were detected in the hippocampal levels of other metabolites, including NAA + NAAG and choline-containing compounds in the ZDF rats, the increase in Glc and Ins levels is in line with elevated brain tissue contents of these metabolites in patients with diabetes mellitus. 相似文献