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Thirty-two adult patients with sickle cell anemia were evaluated endocrinologically. Secondary sex characteristics were abnormal in 29, and eunuchoidal skeletal proportions were present in all except one. The age at which different stages of pubic hair growth were attained in these patients was delayed in comparison to normals (P less than 0.005). Hormonal assays were carried out in 14 patients. Basal serum testosterone, dihydrotestosterone, and androstenedione values were lower (P less than 0.02) in patients than controls. Serum LH and FSH levels before and after stimulation with gonadotropin-releasing hormone were consistent with primary testicular failure. Erythrocyte and hair zinc concentrations were significantly decreased, and there was positive correlation between erythrocyte zinc and serum testosterone (r = 0.61, P less than 0.01) in sickle cell anemia. Our study shows that androgen deficiency in this disease is a result of primary rather than secondary hypogondadism. Further studies are required to establish the role of zinc in the pathogenesis of testicular failure in sickle cell anemia.  相似文献   

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A Ortiz 《Canadian Metallurgical Quarterly》1998,338(16):1162; author reply 1162-1162; author reply 1163
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BACKGROUND: The vascular wall participates in the pathogenesis of sickle cell disease. To determine whether the endothelium is activated in this disease, we studied the number, origin, and surface phenotype of circulating endothelial cells in patients with sickle cell anemia. METHODS: We used immunohistochemical examination of buffy-coat smears to enumerate circulating endothelial cells, and we evaluated the surface phenotype by applying preparations of circulating endothelial cells. An immunofluorescence microscopy panel of antibodies was used, including a specific anti-endothelial-cell antibody, P1H12. RESULTS: Mean (+/-SD) numbers of circulating endothelial cells in normal blood donors, patients with sickle cell trait, and patients with hemolytic anemias not due to hemoglobin S were 2.6+/-1.6, 3.0+/-2.6, and 2.0+/-0.8 per milliliter of whole blood, respectively. Patients with sickle cell anemia who presented with acute painful episodes had 22.8+/-18.2 circulating endothelial cells per milliliter of blood (P<0.001 for the comparison with normal donors), and patients with no such events within one month before or after blood sampling had 13.2+/-11.8 circulating endothelial cells per milliliter of blood (P=0.002 for the comparison with normal donors and P=0.019 for the comparison with patients with acute events). Serial observations of three patients showed a tendency toward higher levels of circulating endothelial cells at the onset of acute painful crises. The average viability of circulating endothelial cells was 66+/-30 percent. In patients with sickle cell anemia, regardless of clinical status, the circulating endothelial cells were predominantly microvascular in origin (CD36-positive), and most of the cells expressed four markers of endothelial-cell activation: intercellular adhesion molecule 1, vascular-cell adhesion molecule 1, E-selectin, and P-selectin. CONCLUSIONS: Our studies suggest that the vascular endothelium is activated in patients with sickle cell anemia, regardless of the patients' clinical status. Adhesion proteins on activated endothelial cells may have a role in the vascular pathology of sickle cell disease.  相似文献   

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Quantitative bioluminescence and single-photon imaging have been applied for mapping concentration distributions of metabolites, such as adenosine triphosphate (ATP), glucose and lactate, in biopsies of cervical cancers in patients. Biopsies were taken before a conventional radiation treatment, and a number of clinically relevant data, such as local tumor control, patient survival, metastatic spread and so forth, were documented. There was no correlation between staging or grading and any of the metabolic parameters measured. Local correlations between ATP, glucose and lactate on a pixel-to-pixel basis were generally positive, with respective Spearman's correlation coefficients less in patients without clinically documented metastasis compared with those with metastatic spread. Lactate concentrations were significantly higher and scattered over a wider range in tumors with metastatic spread in comparison to malignancies in patients without metastasis. Thus, high local lactate levels of > or = 20 mumole/g appear to be associated with a high risk of metastasis, at least in human cervical tumors.  相似文献   

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As a result of a previous trial in which factors influencing swelling of the hand after fasciectomy were studied it was found that unacceptable oedema occurred in hands elevated in a roller towel by night and a high sling by day. An alternative system of elevation in a vacuum splint was investigated and found to reduce post-operative oedema. The advantages and disadvantages of the vacuum splint in the management of the hand after surgery or injury are discussed.  相似文献   

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We report a black girl with sickle cell anemia. On prophylactic exchange transfusion protocol, she experienced cerebrovascular accidents at 3 and 3.5 years of age, both associated with transient right hemiparesis. At 7.5 years of age, she presented with a partial motor seizure and a left hemiparesis. A cerebral angiogram demonstrated stenosis at the origins of both middle and anterior cerebral arteries bilaterally with extensive basal collateralization. She underwent uncomplicated bilateral encephaloduroarteriosynangiosis (EDAS) procedures using both superficial temporal arteries. At age 9 years, the patient presented with a severe headache and tunnel vision secondary to a stenosis of both posterior cerebral arteries. She underwent bilateral EDAS procedures using both occipital arteries. No complication was encountered. Postoperative cerebral angiogram demonstrated impressive neovascularity at the sites of all four EDAS procedures. Different treatment options of moyamoya disease are discussed.  相似文献   

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The role of the vascular endothelium in activation of the coagulation system, a fundamental homeostatic mechanism of mammalian biology, is uncertain because there is little evidence indicating that endothelial cells in vivo express tissue factor (TF), the system's triggering mechanism. As a surrogate for vessel wall endothelium, we examined circulating endothelial cells (CEC) from normals and patients with sickle cell anemia, a disease associated with activation of coagulation. We find that sickle CEC abnormally express TF antigen (expressed as percent CEC that are TF-positive), with 66+/-13% positive in sickle patients in steady-state, 83+/-19% positive in sickle patients presenting with acute vasoocclusive episodes, and only 10+/-13% positive in normal controls. Repeated samplings confirmed this impression that TF expression is greater when sickle patients develop acute vasoocclusive episodes. Sickle CEC are also positive for TF mRNA, with excellent concurrence between antigen and mRNA expression. The TF expressed on the antigen-positive CEC is functional, as demonstrated by a binding assay for Factor VIIa and a chromogenic assay sensitive to generation of Factor Xa. By establishing that endothelial cells in vivo can express TF, these data imply that the vast endothelial surface area does provide an important pathophysiologic trigger for coagulation activation.  相似文献   

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OBJECTIVE: To examine further the role of the amygdala in the recognition of facial expression in adolescents. METHOD: Twelve healthy adolescents were studied using functional magnetic resonance imaging technology during a task of facial affect recognition and a visual control task. RESULTS: All subjects demonstrated a significant increase in signal intensity in the amygdala for the facial expression recognition task. CONCLUSIONS: The data are consistent with previous work in healthy adult subjects implicating the amygdala as essential for the recognition of fearful facial expression.  相似文献   

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The aim of this study was to give reference values for the frequency of morphological sperm abnormalities present in the semen from non-experimental cynomolgus monkeys as well as for the dimensions of sperm heads. Spermatozoa from the liquid portion of electroejaculates from 14 cynomolgus monkeys were air-dried as smears, fixed, and stained with Harris's Haematoxylin and subjected to visual analysis of morphology and computer-aided analysis of ten morphometric variables. The majority (83%) of sperm were morphologically normal. Tail defects were the most common (11%), and showed the highest variation between individuals, the values ranging between 4 and 23%. Head abnormalities consisted of large, tapering, and amorphous forms but were not frequent (0.4%), the values ranging between 0 and 1.3%. Midpiece imperfections were found in all the individuals; the mean percentage was 5%, and the range varied between 3 and 9%. Tail plus midpiece was the only multiple abnormality observed, with a mean value of 1.5% and a range between 0 and 8%. The majority of these double defects consisted of a coiled tail together with a coiled midpiece. Mean values for the morphometric parameters characterizing sperm heads were as follows: area 17.2 microm2, perimeter 15.2 microm, length 5.8 microm, width 4.0 microm, L/W ratio 1.5, gray-level 98, ellipticity 0.2, first shape factor 0.9, second shape factor 1.4, and third shape factor 1.1. Overall coefficients of variation for the majority of parameters were below 7%, showing the great homogeneity in the dimensions of cynomolgus sperm heads. Most useful parameters for sperm characterization, according to their low variability, were perimeter, length, width, L/W ratio, and shape factors. Differences in these parameters were, however, observed between monkeys.  相似文献   

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Sickle cell anemia (SS) patients can be divided into two sub-populations according to peripheral HbF levels. Patients with low (< 9%) HbF levels (LFSS) are characterized by an increased number of circulating BFU-E in active DNA synthesis, and release of burst promoting activity (BPA) by unstimulated low density (LD) adherent cells. In contrast, circulating BFU-E from SS patients with high (> 9%) HbF levels (HFSS) are normal in number, largely in resting phase, and their LD cells do not release BPA-like activity. More recently further heterogeneity has been found among these two groups. In LFSS patients GM-CSF is constitutively produced by unstimulated monocytes. In contrast, HFSS patients' adherent cell depletion increases cycling of BFU-E in culture. CM from HFSS patients inhibits BFU-E expression in culture. Hence, LD adherent cells from HFSS patients may release an inhibitory factor(s). The nature of this factor has to be determined. In addition, there are distinct subpopulations of BFU-E responsiveness to growth factor (GM-CSF, IL-3): a) LFSS patients have a homogeneous BFU-E population, equally responsive to GM-CSF and IL-3; b) HFSS patients, in addition to this subpopulation, have a subset of BFU-E dependent exclusively on IL-3 which is 20 to 40% of the total number of circulating BFU-E. This is similar to BFU-E from normal individuals. Hence, LFSS BFU-E represent an actively proliferating population, equally responsive to GM-CSF and IL-3, controlled by at least constitutively produced GM-CSF and possibly other factors. These observations suggest a significant modification in BFU-E behavior in the subset of SS patients with low HbF levels and high hemopoietic stress. The heterogenous regulation of BFU-E in SS disease seems to be an epiphenomenon of HbF levels, and not vice-versa.  相似文献   

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To provide quantitative information on the sites that promote polymerization of sickle hemoglobin (HbS) after formation of the initial hydrophobic bond involving Val-6(beta) [E6V(beta)] and also to provide hemoglobins with an enhanced polymerization that could be used in a mouse model for sickle cell anemia, we have expressed recombinant double, triple, and quadruple HbS mutants with substitutions on both the alpha- and beta-chains, E6V(beta)/E121R(beta), D75Y(alpha)/E6V(beta)/E121R(beta) and D6A(alpha)/D75Y(alpha)/E6V(beta)/E121R(beta). These recombinant hemoglobins were extensively characterized by high-performance liquid chromatography analysis, sodium dodecyl sulfate-polyacrylamide gel electrophoresis, isoelectric focusing, amino acid analysis, and mass spectroscopy. They retained the functional properties of the Hb tetramer and polymerized in a linear manner at progressively lower Hb concentration as a function of the degree of substitution, suggesting that these remote sites (alphaD6A, alphaD75Y, and betaE121R) on the alpha- and beta-chains exhibit additive, enhanced polymerization properties. The quadruple mutant has a polymerization concentration close to that of the purified SAD hemoglobin from transgenic mouse red blood cells consisting of HbS, Hb Antilles, and Hb D-Punjab. Normal mouse Hb increases the polymerization concentration of each mutant. Thus, the general approach of using recombinant Hbs as described here should prove useful in elucidating the quantitative aspects of the mechanism of HbS polymerization and in identifying the contribution of individual sites to the overall process. The strategy described here demonstrates the feasibility of a systematic approach to achieve future recombinant HbS mutants that could provide a new generation of the transgenic mouse model for sickle cell anemia.  相似文献   

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INTRODUCTION: Magnetic Resonance Imaging (MRI) has been proposed as the diagnostic technique of choice to characterize adrenal tumors. However, the results of the current studies are controversial. MATERIAL AND METHODS: Forty-nine patients with unilateral adrenal masses were submitted to MRI for lesion characterization on the basis of MR signal intensity. Cytology and/or histology demonstrated 14 pheochromocytomas (pheos), 11 adenomas, 3 cysts, 2 myelolipomas, 4 carcinomas, 3 metastases and 1 fibrosarcoma; a clinical diagnosis of adenoma was made in the remaining 11 patients. MR studies were performed using spin-echo (SE) sequences with T1 (TR/TE = 600/17 ms) and T2 (TR/TE = 2000/15-90 ms) weighting. T1-weighted images were also acquired after Gadolinium-DTPA (Gd-DTPA) administration. MR studies were integrated with in- and out-of-phase (TR/TE = 100/4-6 ms) chemical-shift (CS) sequences. MR signal intensity (SI) was analyzed qualitatively and quantitatively; MR results were correlated with tumor type and hormone secretion. RESULTS: The qualitative analysis of T2 images showed high signal intensity in the majority (80%) of adrenal lesions (14 pheos, 12 adenomas, 3 cysts, 2 myelolipomas and 8 malignancies). The quantitative analysis of post-Gd-DTPA T1 images permitted to distinguish adenomas, cysts and myelolipomas from pheos and malignancies. The qualitative analysis of post-Gd-DTPA T2 and T1 images permitted to distinguish pheos and cysts from adenomas and malignancies (p < .05); however, pheos and cysts as well as adenomas and malignancies were not differentiated. MR SI was similar in secreting and nonsecreting adenomas from both a qualitative and a quantitative viewpoints. CS MRI permitted to distinguish adenomas (decreased signal intensity on out-phase relative to in-phase images) from other benign and malignant lesions (no signal change from out-phase to in-phase images). CONCLUSIONS: The qualitative analysis of MR SI on conventional T1 and T2 images does not permit to differentiate adrenal masses. The qualitative evaluation of T1 images after Gd-DTPA administration, the quantitative analysis and CS sequences are technical options improving lesion characterization.  相似文献   

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