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91.
Factor V Quebec revisited 总被引:2,自引:5,他引:2
Factor V Quebec has been described as a bleeding disorder that exhibits an autosomal dominant inheritance pattern and presents severe bleeding after trauma. Two members of a fourth-generation (IV.13 and IV.15) Canadian family have been studied in detail and are the subject of this report. Their clinical presentations and histories have been described previously (Tracy et al: J Clin Invest 74:1221, 1984). Persistent abnormalities include mild thrombocytopenia and defective platelet factor V. Plasma factor V is present at near normal concentration and is fully functional. Thus, the bleeding diathesis appears to reflect the absence of platelet factor V activity. The recent report (Hayward et al: Blood 84:110a, 1994 [suppl, abstr]) of multimerin deficiency in these individuals led us to reevaluate these patients. Western blot analyses of platelet lysates developed with a variety of monoclonal antibodies show that the alpha-granule proteins, fibrinogen, von Willebrand factor, factor V and osteonectin are decreased in concentration and significantly degraded in the platelets of these patients. Thrombospondin, while not degraded, is substantially decreased. In contrast, platelet factor 4 and beta-thromboglobulin do not appear to be affected. These observations suggest that the alpha- granules are correctly assembled but the contents are subsequently subjected to proteolytic degradation. The results indicate that factor V Quebec disorder is probably associated with a generalized defect that leads to degradation of most proteins of the alpha-granules. 相似文献
92.
Satoshi Hisano Winnie Chan Kay Latta Richard J Krieg Jr. James CM Chan 《Clinical and experimental nephrology》1997,1(3):179-186
Growth retardation is a major complication in children with uremia. Protein restriction, calorie deficit, metabolic acidosis,
renal osteodystrophy, and endocrinologic disturbances contribute to the growth failure. The effect of these factors on growth
retardation can be attenuated in part by therapy with vitamin D metabolites, adequate nutrition, alkalization, and dialysis.
Linear growth in children with uremia is markedly retarded despite normal or increased levels of circulating serum growth
hormone. An increased growth hormone level in children with uremia is due to normal growth hormone secretion from the pituitary
gland and impaired growth hormone clearance in the kidney. However, the elevated growth hormone level does not lead to a commensurate
rise in serum insulin-like growth factor I (IGF-I); the serum IGF-I level is decreased or normal in relation to the degree
of renal failure. This discrepancy suggests growth hormone resistance in the liver in uremia. Recent molecular techniques
open a new era in studying the gene expression for growth hormone or IGF-I. There is no doubt today that growth hormone treatment
has the beneficial effect of growth promotion in children with uremia, which also suggests endogenous growth hormone resistance
in target organs or target cells in uremia. 相似文献
93.
Purpose.?To explore disability in women with fibromyalgia with a focus on their work situation.Method.?Review of literature on work status of women with fibromyalgia.Results.?Major differences exist between studies in reported disability and in the percentages of women working. Limitations caused by pain, fatigue, decreased muscle strength, and endurance influence work capacity. However, 34?–?77% of the women work. Individual adjustments in the work situation are reported. When the women find a level that matches their ability, they continue to work and find satisfaction in their work role. Many factors besides degree of impairment or disability influence whether clients with longstanding pain can remain in their work role or return to work after sickness leave.Conclusion.?The total life situation, other commitments, type of work tasks, the ability to influence the work situation, and the physical and psychosocial work environment are important factors in determining whether a person can remain in a work role. More knowledge is needed about how to adjust work conditions for people with partial work ability to the benefit of society and the individual. 相似文献
94.
Pineal germinoma: MR imaging 总被引:6,自引:0,他引:6
Magnetic resonance (MR) imaging characteristics of pineal germinomas are described in seven patients imaged with MR and computed tomography (CT). In patients with symptoms of an enlarging process in the quadrigeminal plate cistern, MR imaging was as sensitive as CT scanning in detecting the mass. MR imaging did not detect a normal-sized, calcified neoplastic gland. Germinoma, germinoma with embryonal cell carcinoma elements, and pineoblastoma demonstrated different MR signal characteristics. Although direct coronal and sagittal MR images were useful in defining the relationship of the tumor to the posterior third ventricle, Sylvian aqueduct, and vein of Galen, the ease, rapidity, and sensitivity of CT scanning suggest that CT should remain the modality of choice for initial evaluation and screening of the pineal region, especially in the younger pediatric population, in whom detection of calcification may provide the only clue of an abnormality. 相似文献
95.
Detection and quantification of chronic cerebrovascular disease: comparison of MR imaging, SPECT, and CT 总被引:1,自引:0,他引:1
Seiderer M; Krappel W; Moser E; Hahn D; Schmiedek P; Buell U; Kirsch CM; Lissner J 《Radiology》1989,170(2):545-548
Twenty patients with angiographically proved occlusion of the internal carotid artery (ICA) (19 unilateral, one bilateral) were studied with magnetic resonance (MR) imaging, iodine-123 iodoamphetamine (IMP) single photon emission computed tomography (SPECT), xenon-133 SPECT, and computed tomography (CT). All patients had a history of stroke or prolonged reversible ischemic neurologic deficit for more than 4 weeks. By regions of interest, T1, T2, regional cerebral blood flow (rCBF), and the number and size of the lesions were determined. The data were expressed as interhemispheric ratios (diseased/nondiseased). The highest ratios obtained were for MR imaging (T1, 2.60 +/- 0.42; T2, 1.61 +/- 0.22 [mean +/- standard deviation]) followed by Xe-133 SPECT (0.58 +/- 0.13) and IMP SPECT (0.56 +/- 0.13). Correlation coefficients for MR imaging (1/T1, 1/T2) and IMP SPECT were below .21. The lesion size was greatest on IMP SPECT images, intermediate on MR images, and least on CT scans. However, MR imaging was superior in detection of pathologic areas (detection rates: MR, 100%; IMP SPECT, 91%; CT, 79%). Relaxation times do not correlate with rCBF. 相似文献
96.
97.
Venous clots: evaluation with MR imaging 总被引:2,自引:0,他引:2
In vitro and in vivo studies were performed to determine the proton relaxation and imaging characteristics of static blood and acute and organized clot in canine jugular veins. In vivo, it was found that two inversion recovery sequences using a short inversion time (100 msec) demonstrated better differentiation of signal intensity of intravascular clot from surrounding soft tissues than did standard T1- and T2-weighted sequences. In vitro, quantitative measurements showed marked reduction of both T1 and T2 relaxation time of acute clot compared with stagnant blood. In addition, the T1 relaxation time, and to a lesser extent the T2 relaxation time, shortened as the clot aged, indicating a potential role for magnetic resonance imaging in determining the age of venous thrombi. 相似文献
98.
Patrícia De Souza Rossignoli Oduvaldo CM Pereira Agnaldo B Chies 《Clinical and experimental pharmacology & physiology》2010,37(3):368-374
1. Orchidectomy results in long‐term testosterone deprivation similar to that observed in male clinical pathologies, such as hypogonadism and age‐related reductions in plasma testosterone concentrations. Although the vascular effects of these sorts of hormone deprivations are known in arteries, they have not been studied to the same extent in veins. 2. The aim of the present study was to determine the effect of orchidectomy, with or without subsequent testosterone replacement (started 23 days after orchidectomy; 10 mg/kg, i.m., testosterone propionate once every 5 days for 3 weeks), on responses of rat isolated portal veins and vena cavae to exogenous phenylephrine (PE). Isolated vessels were mounted in an organ bath and concentration–response curves constructed to PE (10?10–10?4 mol/L), endothelin (ET; 10?10–10?5 mol/L) and KCl (10?2–1.2 × 10?1 mol/L; as a control). 3. Orchidectomy had no effect on contractile responses of either the portal vein or vena cava to KCl. However, orchidectomy enhanced the maximum response (Rmax) of the portal vein, but not the vena cava, to PE. Testosterone replacement had no effect on these responses. The effects of orchidectomy on the Rmax to PE in portal veins were not altered by the nitric oxide synthase inhibitor NG‐nitro‐l‐ arginine methyl ester (10?4 mol/L) alone or combined with 10?5 mol/L indomethacin (a non‐selective cyclo‐oxygenase inhibitor), but they were abolished following treatment of isolated vessels with the ETA and ETB receptor antagonists BQ‐123 and BQ‐788 (both at 10?6 mol/L). Orchidectomy did not alter portal vein responses to the application of exogenous ET. 4. The results of the present study indicate that orchidectomy‐induced decreases in plasma testosterone can increase the venoconstrictor effects of PE on the portal vein and that this effect involves activation of both ETA and ETB receptors by locally produced ET. 相似文献
99.
100.