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51.
J Alvarez J I Casas J M Villar Landeira 《Revista espa?ola de anestesiología y reanimación》1990,37(3):127-136
We evaluated the effects of the use of 1.2% isoflurane (group A) in a group of patients (n = 13) referred for mitral valve surgery, with pulmonary hypertension and right ventricular failure. We evaluated the hemodynamic status in baseline conditions, after isoflurane ++ administration and in relative hyper- and hypovolemia. We compared the results with those in 17 patients (group B) in identical clinical state who did not receive isoflurane during anesthesia. The evaluated parameters were: mixed venous Hb saturation (SvO2), heart rate (HR), pulmonary capillary pressure (PCP), central venous pressure (CVP), mean blood pressure (mBP), mean pulmonary arterial pressure (mPAP), cardiac index (CI), arteriolar pulmonary resistances (APR), peripheral vascular resistances (SVR), stroke index (SI), left ventricular work (LVW), right ventricular work (RVW), and O2 consumption (VO2). In group A, after isoflurane ++ administration, CI was 107.05% and 80% of baseline values in relative hypervolemia and hypovolemia, respectively. In group B (control), CI was 121.48% and 88.28% of basal values in relative hypervolemia and hypovolemia, respectively. In group A, SVR were 73.59% and 76.72% in hypervolemia and hypovolemia, respectively, while in group B they were 86.21% and 106.80%. In group A, APR were 90.85% and 89.96% in hypervolemia and hypovolemia, while they were 80.72% and 102.34% in group B. We found that isoflurane results in a greater peripheral than pulmonary vasodilation with a greater impairment in right ventricular function. 相似文献
52.
53.
IS Park H Kiyomoto F Alvarez YC Xu HE Abboud SL Abboud 《American journal of kidney diseases》1998,32(6):1000-1010
The renal insulin-like growth factor-I (IGF-I) system has been implicated in the pathogenesis of renal hypertrophy, altered hemodynamics, and extracellular matrix expansion associated with early diabetes. The relative abundance of IGF binding proteins (IGFBPs) in the renal microenvironment may modulate IGF-I actions. However, the precise IGFBPs expressed in the glomerular and tubulointerstitial compartments during diabetic renal growth have not been characterized. In the present study, in situ hybridization studies were performed to examine the expression of IGFBP-1 to -6 messenger RNAs (mRNAs) 3, 7, and 14 days after streptozotocin (STZ) injection in rats. In control, nondiabetic kidneys, all six IGFBP mRNAs were differentially expressed with a predominance of IGFBP-5. The onset of renal hypertrophy in STZ-induced diabetes was associated with a rapid and site-specific induction of IGFBP-1, -3, and -5 mRNAs. In contrast, basal expression of IGFBP-2, -4, and -6 mRNAs was not altered in diabetic rats. IGFBP-5 mRNA expression increased in diabetic glomeruli, cortical, and inner medullary peritubular interstitial cells at days 3, 7, and 14. Although normal glomeruli failed to express IGFBP-3, it was induced concomitantly with IGFBP-5 in diabetic glomeruli and cortical peritubular interstitial cells. IGFBP-1 mRNA levels also increased in cortical tubular cells at each time point tested. Peak induction of IGFBP-3 and -5 was observed at day 3, whereas IGFBP-1 was delayed until day 7. IGFBP-1, -3, and -5 mRNA levels declined by day 14, but remained persistently elevated above control. By immunoperoxidase staining, similar alterations in the pattern of IGFBP-3 and -5 protein expression were observed at each time point. The preferential and site-specific increase in IGFBP-1, -3, and -5 suggest that these IGFBPs may regulate the local autocrine and/or paracrine actions of IGF-I and contribute to the pathogenesis of the early manifestations of diabetic nephropathy. 相似文献
54.
Patterns of calcifications and cholangiographic findings in hepatobiliary tuberculosis 总被引:3,自引:0,他引:3
Dean D. T. Maglinte M.D. Sol Z. Alvarez Anastacio C. Ng Jose L. Lapeña 《Abdominal imaging》1988,13(1):331-335
The radiologic findings on conventional examinations (plain films and cholangiograms) in a large group of patients with proven hepatobiliary tuberculosis are reviewed. The plain film findings of large chalky and confluent hepatic calcifications or nodal-type calcifications along the course of the common bile duct are suggestive of hepatobiliary tuberculosis. Small, discrete, scattered calcifications may be mimicked by histoplasmosis but can be differentiated from hepatobiliary tuberculosis. Obstructing defects seen on cholangiography are indicative of tuberculosis when adjacent calcifications are present. The patterns of liver calcifications could provide a clue to the diagnosis of hepatobiliary tuberculosis and its differentiation from liver calcifications of various other etiologies. 相似文献
55.
Elongation of the cytoplasmic domain,due to a point deletion at exon 7, results in an HLA-C null allele,Cw*0409 N 总被引:2,自引:0,他引:2
Balas A Santos S Aviles MJ García-Sánchez F Lillo R Alvarez A Villar-Guimerans LM Vicario JL 《Tissue antigens》2002,59(2):95-100
The development of molecular techniques for HLA typing has allowed the identification of genes previously assigned as serologic blank alleles. Lack or poor cell surface expression has been found for molecules coded by HLA-A, -B, -DRB4, -DRB5, and -DPB1 genes. In this report we describe the first HLA-C gene encoding for a null cell surface molecule. HLA-Cw*0409 N shows a point deletion at position 1095 within exon 7. This mutation provokes a codon reading shift, generating a new translation stop codon 97 bp downstream to that described in alleles normally expressed. This new stop codon location implies the presence of 32 extra amino acid residues in the cytoplasmic domain. Transfection experiments suggest that elongation of the cytoplasmic domain in Cw*0409 N would be the cause of cell surface expression failure, although Cw*0409 N heavy chain is able to create stable complexes with beta2-microglobulin. HLA-C fragment length analysis in a small selected group of samples with B44-Cblk haplotypic associations allowed us to identify two additional subjects showing both a serologic silent Cw*04 allele and a point base deletion at the 3' end of the HLA-C gene. This finding indicates that the allele frequency of Cw*0409 N within serologic C blank alleles would be appreciable, although basically restricted to the (A23)-Cw*0409 N-B*4403-DR7-DQ2 haplotype. 相似文献
56.
Alvarez JC Díaz C Suárez C Fernández JA González del Rey C Navarro A Tolivia J 《Mechanisms of ageing and development》2000,114(3):149-172
The data concerning the effects of age on the brainstem are scarce and few works are devoted to the human vestibular nuclear complex. The study of the effects of aging in the vestibular nuclei could have clinical interest due to the high prevalence of balance control and gait problems in the elderly. We have used in this work eight human brainstems of different ages sectioned and stained by the formaldehyde-thionin technique. The neuron's profiles were drawn with a camera lucida and Abercrombie's method was used to estimate the total number of neurons. The test of Kolmogorov-Smirnov with the correction of Lilliefors was used to evaluate the fit of our data to a normal distribution and a regression analysis was done to determine if the variation of our data with age was statistically significant. Aging does not affect the volume or length of the vestibular nuclear complex. Our results clearly show that neuronal loss occurs with aging in the descending (DVN), medial (MVN), and lateral (LVN) vestibular nuclei, but not in the superior (SVN). There are changes in the proportions of neurons of different sizes but they are not statistically significant. The neuronal loss could be related with the problems that elderly people have to compensate unilateral vestibular lesions and the alterations of the vestibulospinal reflexes. The preservation of SVN neurons can explain why vestibulo-ocular reflexes are compensated after unilateral vestibular injuries. 相似文献
57.
Quantitative study of the immunoglobulin-containing cells in trephine samples of bone marrow 下载免费PDF全文
Immunoglobulin (Ig) was demonstrated in paraffin sections of 12 trephine bone marrow biopsies by means of the unlabelled antibody peroxidase-antiperoxidase (PAP) method. The Ig-containing cells, which were counted with the Reichert-Jung (Kontron) MOP-AMO3 user-controlled image-analyser, were found to constitute approximately 4·2% of all the nucleated cells in the marrow, a figure significantly higher than those reported by previous workers. 相似文献
58.
Romero Gómez MP Peinado Esteban AM Sobrino Daza JA Sáez Nieto JA Alvarez D Peña García P 《Journal of clinical microbiology》2004,42(7):3371-3373
We describe a case of infective endocarditis in a prosthetic mitral valve due to Ochrobactrum anthropi. Although O. anthropi is an emerging pathogen in immunocompromised patients, infections with the bacterium have very rarely been documented in healthy hosts, and endocarditis is rare. To our knowledge, only two cases of O. anthropi endocarditis have been reported in the medical literature. 相似文献
59.
Visualizing cytokine-secreting cells in situ in the rhesus macaque model of chronic gut inflammation
Ramesh G Alvarez X Borda JT Aye PP Lackner AA Sestak K 《Clinical and diagnostic laboratory immunology》2005,12(1):192-197
Cytokine-producing cells in gut-associated lymphoid tissues of rhesus macaques with chronic enterocolitis were studied. The confocal microscopy technique that we developed enables simultaneous in situ visualization of multiple extra- and/or intracellular antigens at a resolution higher than that allowed by light or epifluorescence microscopy. The presence of interleukin-6 (IL-6)-, tumor necrosis factor alpha (TNF-alpha)-, and IL-1-alpha-producing cells was focally intense in the colon lamina propria of the affected animals. The IL-1-alpha-producing cells were T lymphocytes (CD3+), while the TNF-alpha-producing cells were both macrophages (CD68+/HAM56+/LN5+) and T lymphocytes (CD3+). The IL-6-producing cells within the colon consisted of T lymphocytes and macrophages. The amount of IL-6-producing cells seen in macaques with enterocolitis was significantly higher (P<0.001) than that seen in the healthy control animal, while TNF-alpha- and IL-1-alpha-producing cells were seen only in macaques with enterocolitis. Most of the T lymphocytes that produced cytokines were detected in the lamina propria, while the macrophages were most prominent in highly inflamed regions of the lamina propria. Taken together, our findings indicate that there might be immunological similarity between chronic enterocolitis of rhesus macaques and humans, suggesting the potential use of the nonhuman primate model for the validation of novel therapies. 相似文献
60.
Laura A Hawryluck William RC Harvey Louise Lemieux-Charles Peter A Singer 《BMC medical ethics》2002,3(1):3-9