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21.
We report a 89-year-old female diagnosed with chronic myelomonocytic leukemia (CMMoL) presenting with a monosomy 15. To our knowledge, this is the second reported case of CMMoL with monosomy 15. On the other hand, monosomy 15 in complex karyotypes is a frequent chromosome aberration in myelodysplastic syndromes, particularly in refractory anemia with excess of blasts.  相似文献   
22.
The effects of the chronic inhibition of nitric oxide (NO) on renal hemodynamics and tubular function were studied in rats treated for 8 weeks with the NO synthesis inhibitor, N(G)-nitro-L-arginine methyl ester (L-NAME; 40 mg/kg/day). In addition, the effect of L-NAME administration on vasoactive systems (renin-angiotensin system, aldosterone, catecholamines, endothelin, and thromboxane A(2)) was evaluated. Chronic inhibition of NO significantly elevated blood pressure, reduced glomerular filtration rate and renal blood flow, blunted the pressure-diuresis-natriuresis response, and increased protein urine excretion. All these changes were associated with blunted nitrite production in response to acetylcholine in glomeruli. No changes were observed in the plasma levels of either renin activity, aldosterone, or endothelin in L-NAME-treated rats. Similarly, no differences were observed in the urinary excretion of thromboxane B(2) between both group of animals. By contrast, plasma concentrations of both epinephrine and norepinephrine were elevated in rats treated with L-NAME. In summary, the results show that chronic blockade of NO produced not only alterations in renal function, but also renal damage, suggesting an important renoprotective role of NO. An activation of sympathoadrenal system could participate in these renal alterations.  相似文献   
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BACKGROUND: Posttraumatic stress disorder (PTSD) is a common and disabling disturbance in primary care. Few studies have been carried out in primary care samples and none have taken into consideration the association between PTSD and personality disorder. AIM: To describe prevalence and risk factors of PTSD and its comorbidity with personality disorder. SETTING: General practice centre in Valencia (Spain). METHOD: Patients who had experienced at least one traumatic event in their lives were selected from a random sample attending a primary healthcare centre in Valencia and blindly assessed by trained professionals. Patients suffering from PTSD were compared with those who were not. PTSD and personality disorder diagnoses were established using CIDI and SCID-II interviews respectively. Sex, age at the time of experiencing trauma, frequency, multiplicity and type of trauma, dissociative symptoms, personality disorder and severity of PTSD were subjected to multivariate analysis to estimate the probability of developing PTSD and its duration. RESULTS: Life prevalence rate was 14% and current prevalence 9%. Dissociative symptoms and personality disorder were significantly associated with PTSD. Cluster analysis based on age, frequency and type of trauma revealed the existence of one subgroup composed mainly of women who had experienced frequent body-contact trauma at an early age, developed severe PTSD and suffer from a variety of personality disorders, particularly paranoid personality disorder. Time to the complete disappearance of symptoms was only explained by the initial severity of PTSD. CONCLUSION: PTSD is a frequent disorder in general practice and it is often associated with personality disorder. Women who experienced high frequency body-contact traumatic events at an early age often suffer from personality disorder and present a particularly severe form of PTSD deserving referral to specialised care.  相似文献   
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The net impact of cytomegalovirus (CMV) DNAemia on overall mortality (OM) and nonrelapse mortality (NRM) following allogeneic hematopoietic stem cell transplantation (allo-HSCT) remains a matter of debate. This was a retrospective, multicenter, noninterventional study finally including 749 patients. CMV DNA monitoring was conducted by real-time polymerase chain reaction (PCR) assays. Clinical outcomes of interest were OM and NRM through day 365 after allo-HSCT. The cumulative incidence of CMV DNAemia in this cohort was 52.6%. A total of 306 out of 382 patients with CMV DNAemia received preemptive antiviral therapy (PET). PET use for CMV DNAemia, but not the occurrence of CMV DNAemia, taken as a qualitative variable, was associated with increased OM and NRM in univariate but not in adjusted models. A subcohort analysis including patients monitored by the COBAS Ampliprep/COBAS Taqman CMV Test showed that OM and NRM were comparable in patients in whom either low or high plasma CMV DNA threshold (<500 vs ≥500 IU/mL) was used for PET initiation. In conclusion, CMV DNAemia was not associated with increased OM and NRM in allo-HSCT recipients. The potential impact of PET use on mortality was not proven but merits further research.  相似文献   
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Mantle cell lymphoma (MCL) is a B-cell neoplasm with a relatively aggressive clinical course. There is a very small subgroup of patients who present with atypical lymphocytes in peripheral blood, with or without lymphocytosis, lymphadenopathy, or splenomegaly, and with an indolent clinical course. They frequently show mutated IgV(H) genes and CD5 negativity. We report an asymptomatic elderly patient who presented with a single submandibular lymphadenopathy. The biopsy showed immunophenotype and t(11;14)(q13;q32) consistent with MCL. The abnormal lymphoid population was also detected in peripheral blood and bone marrow. The patient has remained asymptomatic for 5 years without receiving any therapy. It is uncertain whether these cases represent an early-stage event in the development or an indolent form of MCL. The existence of such asymptomatic patients with an indolent clinical course should induce a strict clinical judgment in terms of therapeutic decisions.  相似文献   
29.
A reinforced rigid fixation device for unstable intertrochanteric fractures   总被引:14,自引:0,他引:14  
A 120 degrees blade plate reinforced by a strut is introduced for the treatment of unstable intertrochanteric and proximal subtrochanteric fractures. Mechanical tests showed that the strength of this reinforced resistance device was 11,758 N. This strength is two and three times greater than that of the Gamma nail and sliding hip screw, respectively, and five times greater with the strut than without it. Three hundred fifty-eight patients older than 60 years of age were treated with this method between 1987 and 1991 (mean followup, 16 months). Six months after surgery the fracture had united in 82% of the patients who were walking without aid or using only a cane. Weightbearing began when the patient's general overall condition allowed such activity (average, 5 days; mode, 3 days). A chi squared test showed no difference regarding the results between stable and unstable fractures. Intraoperative and postoperative complication rates were 3% and 7.1%, respectively. The failure of fixation rate was 5.4%. Mechanical tests and clinical results showed that immediate weightbearing can be allowed in all types of intertrochanteric fractures. This reinforced device is effective in treating unstable intertrochanteric fractures and is especially indicated for the most unstable types (Evans' Grades 4 and 5).  相似文献   
30.
Severe dietary restriction delays the physical development of rodents and leads to adult animals of reduced body size but significantly increased life expectancy. We tried to find a similar relationship in human populations using demographical and statistical methods. We show for the total Spanish male population that the mean adult body height reliably reflects the regional living and nutritional conditions. This relation does not only hold for todays socioeconomic data but can also be reproduced using data on family income in the mid 19th century. We calculated the mean height of young men liable to the military service around 1860 and determined their longevity retrospectively using posterior census data. This was done separately for all the Spanish provinces. The linear regression between both parameters manifests a statistically highly significant relationship: the smaller the mean height at age 18 in a province, the higher the chance for people living there to reach high chronological ages. Migrational movements, selection, mortality due to epidemics or unreliability of the population censuses can be largely ruled out as explications for the described correlation. Furthermore, we determined the secular growth trend in Spain for the last 130 years. From 1860 to 1920 the mean height increased by 2.7 cm, from 1920 to 1987 by another 9.8 cm. Since 1950 the trend is above 2 cm per decade country-wide. From 1974 onwards it amounts to 2.89 +/- 0.17. Such high values were worldwide looked upon as isolated cases found only in geographically and socially isolated population subgroups during very limited periods.  相似文献   
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