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51.
A 12-year-old girl had a lesion located on the upper part of the scalp that was clinically interpreted as a melanocytic nevus and corresponded histologically to a basal cell carcinoma. At age 2 years she had been diagnosed as having acute lymphoblastic leukemia L1, for which she was treated with systemic chemotherapy. She also received telecobalt therapy to the whole cranium for prophylaxis of meningeal leukosis. Having rejected other possible causes that can favor the appearance of basal cell carcinoma during childhood (basal cell nevus syndrome, nevus sebaceus, albinism, etc.), we believe that this case should be added to the five previously reported in the literature as basal cell carcinoma developing at an early age in cranial radiation portals with megavoltage radiotherapy. We draw attention to the need to explore radiated areas of skin as part of the long-term follow-up of these patients, and to the advisability of obtaining a biopsy from any persistent lesion in these areas.  相似文献   
52.
Serum Prolactin in Neonates with Seizures   总被引:5,自引:0,他引:5  
Summary: We studied serum prolactin (PRL) in 28 newborn infants with acute encephalopathy. Six patients had electrographically confirmed seizures. Twenty-two patients comprised the nonictal group. In the seizure group, PRL was determined at the first onset of the seizure (baseline) and at 15 and 30 min postictal. In the nonseizure group, PRL was determined at the end of the EEG and 15 min later. EEGs were visually analyzed for the presence of seizures and background abnormality (normal or mildly, moderately, or markedly abnormal). Etiologic diagnoses included congenital heart disease (12), hypoxic-ischemic encephalopathy (4), sepsis (4), respiratory distress syndrome (5) meconium aspiration (1), and metabolic disease (2). Serum PRL was significantly higher (p < 0.05) at baseline and 15 min postictally in the patients with seizures than in the nonictal group. However, PRL levels 15 and 30 min postictally were not statistically different from baseline values. Baseline PRL correlated significantly (p < 0.001) with EEG background abnormality in both groups; therefore, patients with the most abnormal EEG backgrounds had higher levels of PRL than those with a relatively normal EEG background. We conclude that newborns with EEG-confirmed seizures, particularly if seizures are not associated with clinical signs, have high baseline serum PRL levels that do not increase significantly in the immediate postictal period. Serum PRL levels correlate with the severity of the brain insult as evaluated by EEG background. Further studies are needed to enhance our understanding of the dynamics of PRL secretion in newborns with seizures and acute encephalopathy.  相似文献   
53.
Deviations in the determination of the unperturbed dimensions of polymers arising in ternary polymer systems (solvent (1)/solvent (2)/polymer) can be explained by the inaccurate use of an interaction parameter independent of polymer molecular weight. On this basis, a new formalism for the calculation of the second virial coefficient from intrinsic viscosity is proposed. This formalism was tested (and compared with well established formalisms) for all ternary polymer systems with simultaneous intrinsic viscosity and second virial coefficient data in the literature.  相似文献   
54.
BACKGROUND: The success of sirolimus and low-dose tacrolimus in islet cell transplantation has influenced many transplant centers to utilize this novel regimen. The long-term safety and tolerability of this steroid-free immunosuppressive protocol for allogeneic islet transplantation has yet to be determined. METHODS: We transplanted 26 adult patients with long standing type 1 diabetes mellitus between April 2000 and June 2004. Immunosuppression consisted of induction with daclizumab and maintenance therapy with tacrolimus and sirolimus. Adverse events (AEs) in patients were followed and graded using the Common Terminology Criteria for Adverse Events, version 3.0 (National Cancer Institute). RESULTS: To date, the majority of patients were able to remain on the immunosuppression combination for up to 22+/-11 months. Four patients were successfully converted to Mycophenolate Mofetil due to tacrolimus-related toxicity. Withdrawal from immunosuppression was decided in four patients due to hypereosinophilic syndrome, parvovirus infection, aspiration pneumonia, and severe depression, respectively. Six patients required filgrastim therapy for neutropenia. Transient elevation of liver enzymes was observed in most patients early after islet infusion. Increased LDL in 20 patients required medical treatment. CONCLUSION: There was a varying range of AEs, most of them mild and self-limiting; however, some required urgent medical attention. The majority of patients were able to tolerate and remain on this effective regimen. To date, no deaths, cytomegalovirus disease, graft-versus-host disease, or posttransplant lymphoproliferative disease has been observed.  相似文献   
55.
Fifty-four consecutive acute Achilles tendon ruptures were treated with end-to-end suture augmented with gastrocnemius fascial flaps. Surgery was performed within 24 h. Mean patient age was 35 (23–57) years, and 46 were men. Mean follow-up time was 4.8 (2–8) years. At follow-up, the mean visual analogue scale for pain was 0.49, and the mean AOFAS ankle–hindfoot score was 95 (74–100) points. Fifty-three patients were able to stand on their tiptoes for 30 s and perform repeated toe raises, and 50 patients were able to perform single-limb hopping. Complications included rerupture in one case, deep infection in three cases, delayed wound healing in eight cases, and deep venous thrombosis in one case. Reconstruction of acute ruptures of the Achilles tendon augmented with gastrocnemius-soleus fascial flaps provided a good outcome but was associated with a high complication rate.
Résumé Cinquante-quatre ruptures récentes, consécutives, du tendon dachille ont été traitées par suture bout à bout augmentée par un lambeau fascial du muscle jumeau. La chirurgie a été exécutée dans les vingt-quatre heures suivant la rupture. Lâge moyen des malades était de 35 ans (23–57) et 46 étaient de sexe masculin. Le temps de suivi moyen était de 4,8 ans (2–8). Au dernier examen la cotation visuelle moyenne pour la douleur était 0,49 et le score moyen de cheville AOFAS était de 95 points (74–100). Cinquante-trois malades étaient capables de se tenir sur la pointe des pieds trente secondes et dexécuter des extensions dorteils répétées, et 50 malades étaient capables dexécuter un sautillement monopodal. Les complications ont été une rupture itérative dans un cas, une infection profonde dans trois cas, un retard de cicatrisation cutanée avec évolution favorable dans huit cas, et une thrombose veineuse profonde dans un cas. La reconstruction des ruptures récentes du tendon dachille avec utilisation dun lambeau du fascia des jumeaux a fourni un bon résultat mais avec un taux élevé de complications.
  相似文献   
56.
Quality in Surgery: Current Issues for the Future   总被引:2,自引:0,他引:2  
  相似文献   
57.
BACKGROUND: A number of cross-sectional or serial studies have demonstrated the clinical impact of microproteinuria and macroproteinuria by identifying individuals at risk of both end-stage renal disease and major cardiovascular events. This study focused on the prevalence of proteinuria in Mexico and its relationship with other cardiovascular risk factors such as hypertension, type 2 diabetes mellitus, body mass index, smoking, age, and gender. METHODS: The prevalence of proteinuria in Mexico was obtained from the probabilistic cross-sectional national health survey performed in the year 2000. The proportion of urine dipstick samples that tested positive for protein (defined as > or =1+) in adults from 20 to 69 years of age was determined. The analysis was performed using both algebraic and multicategorical models. Potential interactions between proteinuria and other major cardiovascular risk factors were investigated. RESULTS: A total of 46,523 adult survey participants were included in the analysis. In the general population, 9.2% had proteinuria. By univariate, multivariate, and multicategorical analysis, hypertension, diabetes, obesity, and age were strongly associated with the prevalence of proteinuria (P < 0.001). However, in Mexico, the specific distribution of age groups demonstrated that the absolute number of patients without hypertension that had proteinuria is not irrelevant. To identify 1 case of proteinuria, one would need to screen 3 persons with diabetes mellitus, 5 patients with hypertension without diabetes, or 6 persons over the age of 55 years. When proteinuria is present, the probability of having a noncommunicable chronic disease or other major cardiovascular risk factor is more than 85%. CONCLUSION: Proteinuria is prevalent. When considered together, dipstick-positive proteinuria, blood pressure level, body mass index > or =30 m(2)/kg, and abnormal fasting blood glucose measured on a single occasion identifies different segments of the population. Studies such as this may be a suitable initial clinical approach to general population screening for renal and cardiovascular risk stratification.  相似文献   
58.
Soluble p-cadherin found in human semen   总被引:2,自引:0,他引:2  
Cadherins constitute a family of calcium-dependent cell-cell adhesion molecules. P (placental)-cadherin is a 118-kd protein expressed by basal cells in epithelial tissues. P-cadherin also has been described as a soluble protein in certain biological fluids, including human serum and breast milk. Here, we report the presence of an 80-kD fragment of P-cadherin in human semen. No significant differences were found in semen samples from fertile and nonfertile patients. Our results add evidence to previous data indicating that soluble fragments of P-cadherin have a widespread distribution in bodily fluids and suggest that soluble P-cadherin might have functions other than basal epithelial cell-cell adhesion.  相似文献   
59.
When A strain mice are placed in parabiotic union with (A x C57Bl/1)F1 hybrid partners, the parental strain partners are polycythemic and the hybrids anemic from the 5th through the 16th parabiosis days. All hybrids develop clinical intoxication between the 7th and the 12th days, and no pairs survive to 1 month. Long-term survival of parabiotic pairs can be achieved if lethally irradiated or specifically tolerant parental strain mice are united to hybrid partners. Production of tolerance by either of these methods results in elimination of anemia-polycythemia by the 12th parabiosis day and prevents intoxication in the hybrid partners. Preimmunization of the parental strain partners against the C57Bl/1 component of the hybrid leads to a considerable intensification of day 5 anemia-polycythemia. Intoxication develops in the hybrid partners between the 4th and the 6th days after union. It is concluded that anemia is primarily responsible for the syndrome of clinical intoxication. Early anemia-polycythemia on day 5 does not depend upon an immunological mechanism, but the late anemia-polycythemia appearing between days 12 and 16 is a function of the ability of the parental strain mouse to react immunologically against its hybrid partner. When neonatally thymectomized A strain mice are joined to hybrid partners, anemia-polycythemia is sustained through the 16th day and the hybrid partners develop clinical intoxication. On the other hand, when both partners are neonatally thymectomized, late anemia-polycythemia is considerably reduced, and the hybrid partners apparently do not develop clinical intoxication. It is concluded that normal hybrid mice are capable of reconstituting the immunological capacity of their thymectomized partners, whereas thymectomized hybrid mice do not have this restorative capacity. These findings are discussed in terms of their possible application to the problem of the induction of immunological tolerance in adult mice by the parabiosis procedure.  相似文献   
60.
Maintenance therapy in patients with aggressive malignant lymphoma using biological modifiers remains uncertain. We conducted a controlled clinical trial to evaluate the efficacy and toxicity of interferon-alpha 2b, cyclophosphamide, and prednisone as maintenance therapy in patients with aggressive diffuse large B cell lymphomas in complete remission after aggressive chemotherapy. In an intent-to-treat analysis, 169 patients were eligible for this study; the end points were event-free survival (EFS) and overall survival (OS). With a median follow-up of 49.3 months, no statistical differences were observed and actuarial curves at 5 years showed that EFS was 71% (95% confidence interval [CI], 63-79%) for patients who received maintenance compared to 63% (95% CI, 59-71%) for patients in control group (p = 0.05). No statistical differences were observed in OS between maintenance arm: 84% (95% CI, 78-89%) and control group 83% (95% CI, 77-88%) in control group (p = 0.2). All patients received the maintenance therapy as planned and in time, thus dose intensity was considered 1.0 in all cases. Acute toxicity was mild, and no delay or suspension of treatment was necessary. Late toxicity was not evident until now. We conclude that use of maintenance therapy combining interferon-alpha 2b, cyclophosphamide, and prednisone is not useful in patients with aggressive lymphoma if they had been treated with aggressive combined chemotherapy.  相似文献   
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