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81.
Stromal osseous metaplasia in metastatic adenocarcinoma of the gallbladder.   总被引:1,自引:0,他引:1  
A case of stromal osseous metaplasia in the abdominal scar metastasis of a gallbladder adenocarcinoma is described. The occurrence of stromal osseous metaplasia in carcinomas probably does not affect prognosis; however, it must be recognized to avoid a misdiagnosis of carcinosarcoma.  相似文献   
82.
Eighty-six children were diagnosed with cancer in infancy, followed for at least 5 years, and assessed for late effects of disease and therapy. One child subsequently died from respiratory failure and 3 died from second primary cancers. Another patient survived second primary cancers of the skin. The high frequency of new cancers (4 observed, 0.09 expected) was attributable to host susceptibility factors and treatment effects. Kyphoscoliosis was diagnosed in 44 patients, 40 of whom had received radiotherapy to the spine. Other patients had neurologic deficits, pulmonary fibrosis, hypoplastic breasts, bowel adhesions, thyroid nodules, musculoskeletal defects, and liver fibrosis associated with tumor therapy. Sequelae of cancer were more common after treatment in infancy than in later childhood. Improved treatments and knowledge of natural history can reduce adverse effects of therapy.  相似文献   
83.
The use of extracorporeal membrane oxygenator instead of standard cardiopulmonary bypass during lung transplantation is debatable. Moreover, recently, the concept of prolonged postoperative extracorporeal membrane oxygenator (ECMO) support has been introduced in many transplant centers to prevent primary graft dysfunction (PGD) and improve early and long-term results. The objective of this study was to review the results of our extracorporeal life support strategy during and after bilateral sequential lung transplantation (BSLT) for pulmonary artery hypertension. We review retrospectively our experience in BSLT for pulmonary artery hypertension between January 2010 and August 2018. A total of 38 patients were identified. Nine patients were transplanted using cardiopulmonary bypass (CPB), in eight cases CPB was followed by a prolonged ECMO (pECMO) support, 14 patients were transplanted on central ECMO support, and seven patients were transplanted with central ECMO support followed by a pECMO assistance. The effects of different support strategies were evaluated, in particular in-hospital morbidity, mortality, incidence of PGD, and long-term follow-up. The use of CPB was associated with poor postoperative results and worse long-term survival compared with ECMO-supported patients. Predictive preoperative factors for the need of intraoperative CPB instead of ECMO were identified. The pECMO strategy had a favorable effect to mitigate postoperative morbidity and mortality, not only in intraoperative ECMO-supported patients, but even in CPB-supported cases. In our experience, ECMO may be considered as the first choice circulatory support for lung transplantation. Sometimes, in very complex cases, CBP is still necessary. The pECMO strategy is very effective to reduce incidence of PGD even in CPB-supported patients.  相似文献   
84.
85.
Low birth weight and slow growth are frequently observed in the patients with cri-du-chat syndrome. To provide a growth reference standard for children with cri-du-chat syndrome, syndrome-specific growth charts have been developed from a combination of cross-sectional and longitudinal measurements on 374 patients from North America, Italy, Australia, and the British Isles. The data were obtained from pediatric records, parent reporting, and personal examinations at national 5p- parent support group meetings in the U.S., Italy, U.K., and Australia. The growth curves include height and weight measurements for patients ages 0 to 18 years and head circumference measurements for patients ages 0 to 15 years. Birth weight was above the 5th percentile of general population in 50% of cases: mean weight 2.8 kg +/- 1.85 SD for males and 2.6 kg +/- 1.51 SD for females. Growth curve medians were usually at or below the 5th centile of reference populations throughout life. The median head circumference falls below the 2nd centile, and this change increases with age. The charts show that compared with the standard population, most children with cri-du-chat syndrome are small at birth and as they grow most, but not all, have significant microcephaly and compromised weight for age, and to a lesser extent, compromised height for age. Am. J. Med. Genet. 94:153-162, 2000.  相似文献   
86.
Survival after childhood cancer has been improving since the late 1970s in most developed countries. The Childhood Cancer Registry of Piedmont has been recording malignant tumors in children (0–14 years) throughout Piedmont since 1967. The present paper is based on the records of the 2,970 children diagnosed during the period 1970–2001; survival rates are estimated up to June 30, 2004. Based on records from the Registrar Offices of the relevant towns of residence, 1,698 children were reported to be alive, 1,252 deceased, and 20 were of unknown vital status. Over the period 1970–2001, 5-year survival rates for all tumor types combined showed a statistically significant increasing trend (p<0.0001). For acute lymphocytic leukemia, the survival rate increased steadily from 24.7% (95% CI 15.0–34.3) in 1970–1974 to 87.8% (82.1–93.6) in 1995–1999. Five-year survival rates for central nervous system tumors increased from 32.8% (21.0–44.6) in 1970–1974 to 80.3% (72.6–88.0) in 1990–1994 and decreased thereafter. Age of less than 1 year at time of diagnosis was a favorable prognostic factor for neuroblastoma and ganglioneuroblastoma. The extent of disease at diagnosis was related to prognosis for neuroblastoma and ganglioneuroblastoma and other selected solid tumors. A white blood cell count greater than 50,000×106 cells/l was associated with decreased survival in children with acute lymphocytic leukemia and acute non-lymphocytic leukemia. We have found positive trends in survival for all tumor types in Piedmont, similar to those reported by other population-based cancer registries. Age, extent of disease, and white blood cell count at diagnosis are prognostic factors for selected cancer sites.  相似文献   
87.
Objective: This study sought to evaluate the anemia prevalence and effect of anemia treatment in pregnant adolescents.

Methods: A cross-sectional study. Data from perinatal outcomes, serum hemoglobin level and iron supplementation were collected. Samples were divided into three groups: pregnant adolescents without anemia, with treated anemia and with untreated anemia. Frequencies, means, standard deviations and Chi-squared values were calculated. The significance level was 5%, and the software used was Epi-info 7.

Results: The study included 458 pregnant adolescents. The mean age was 16 years old, and the prevalence of anemia was 41.27% (189). Mild, moderate or severe anemia were presented in 65.60%, 33.86% and 0.52%, respectively, of study participants. Among pregnant adolescents with anemia, 87.24% received treatment with iron supplementation. Preterm labor (p?=?0.003), gestational age at birth <37 weeks (p?=?0.036) and stillbirth (p?=?0.004) showed an association with nontreated anemia. Positive HIV was more prevalent in adolescents with nontreated anemia (p?=?0.018). The cesarean rate was 36.90%, with no difference between groups.

Conclusion: Anemia is a public health problem among pregnant adolescents, and iron supplementation reduces negative neonatal outcomes. Treatment adherence by a multidisciplinary and qualified prenatal care team can be key in reducing adverse neonatal outcomes associated with pregnancy during adolescence.  相似文献   
88.
Neurohormonal activation has been shown to be a major factor in congestive heart failure progression and mortality. The beneficial effects obtained in clinical trials with angiotensin converting enzyme (ACE) inhibitors, beta-blockers and aldosterone antagonists have confirmed this hypothesis. 5,6-Diisobutirroyloxy-2-methyl-aminotetraline hydrochloride (nolomirole) is a selective agonist of prejunctional D(2)-dopaminergic and alpha(2)-adrenergic receptors. The stimulation of these receptors inhibits catecholamine release from sympathetic nerve endings. To confirm that this mechanism can be useful in congestive heart failure, we studied the effects of nolomirole on monocrotaline-induced congestive heart failure. The ACE inhibitor trandolapril was used as reference compound. Rats were given single intraperitoneal injection of either saline (control group; n=20) or monocrotaline (50 mg kg(-1)). Three days later, the monocrotaline-treated animals were randomly allocated (n=50 per group) to oral treatment with distilled water (vehicle group), nolomirole (0.25 mg kg(-1)) twice a day, or trandolapril (0.3 mg kg(-1)) once a day up to sacrifice. On the fourth week after monocrotaline injection, animals with signs of congestive heart failure were sacrificed for evaluation of heart hypertrophy and neuroendocrine alterations. Atrial natriuretic peptide (ANP) and alderosterone were determined by radioimmunoassay in plasma. Tissue norepinephrine concentration was quantified by high-pressure liquid chromatography. Nolomirole and trandolapril significantly reduced (a) hypertrophy of right atria and ventricles, (b) plasma levels of ANP and presence of pleural/peritoneal effusions and (c) norepinephrine depletion of right ventricle. These findings confirmed that nolomirole, like trandolapril, is able to attenuate the heart failure signs in the monocrotaline-induced congestive heart failure model.  相似文献   
89.
BACKGROUND AND PURPOSE: Intact endothelium plays a pivotal role in post-ischaemic angiogenesis. It is a phenomenon finely tuned by activation and inhibition of several endothelial receptors. The presence of alpha(1)-adrenoceptors on the endothelium suggests that these receptors may participate in regenerative phenomena by regulating the responses of endothelial cells involved in neo-angiogenesis. EXPERIMENTAL APPROACH: We evaluated the expression of the subtypes of the alpha(1)-adrenoceptor in isolated endothelial cells harvested from Wistar-Kyoto (WKY) rats. We explored the possibility these alpha(1)-adrenoceptors may influence the pro-angiogenic phenotype of endothelial cells in vitro. In vivo, we used a model of hindlimb ischaemia in WKY rats, to assess the effects of alpha(1) adrenoceptor agonist or antagonist on angiogenesis in the ischaemic hindlimb by laser Doppler blood flow measurements, digital angiographies, hindlimb perfusion with dyed beads and histological evaluation. KEY RESULTS: In vitro, pharmacological antagonism of alpha(1)-adrenoceptors in endothelial cells from WKY rats by doxazosin enhanced, while stimulation of these adrenoceptors with phenylephrine, inhibited endothelial cell proliferation and DNA synthesis, ERK and retinoblastoma protein (Rb) phosphorylation, cell migration and tubule formation. In vivo, we found increased alpha(1)-adrenoceptor density in the ischaemic hindlimb, compared to non-ischaemic hindlimb, suggesting an enhanced alpha(1)-adrenoceptor tone in the ischaemic tissue. Treatment with doxazosin (0.06 mg kg(-1) day(-1) for 14 days) did not alter systemic blood pressure but enhanced neo-angiogenesis in the ischaemic hindlimb, as measured by all our assays. CONCLUSIONS: Our findings support the hypothesis that the alpha(1)-adrenoceptors in endothelial cells provide a negative regulation of angiogenesis.  相似文献   
90.
This work proposes an alternative green and selective biocatalytic route for Glycerin Monostearate (α-monostearin) production. The conventional method of production uses an elevated temperature. Apart from the high energy consumption, such high temperatures darken the final product's color, lead to random reactions, and produce high orders of diglycerides and triglycerides instead of monoglycerides. The proposed production process was performed by esterifying stearic acid with glycerin in an organic medium using Candida antarctica lipase (Novozym 435) at a mild temperature. The reaction conditions were optimized using the response surface methodology (RSM): optimum conditions were a temperature of 60 °C, glycerin to stearic acid molar ratio of 8:1, and Novozym 435 amount of 6% w/w. The solvent addition remarkably improved the α-monostearin yield to nearly 80% without the need for the energy-intensive distillation step. The conventional autocatalytic esterification (AUT) process was also performed to investigate the comparative monoglyceride yield, and it was found to be 22.5%. Proton nuclear magnetic resonance and gas-chromatography confirmed that α-monostearin could be produced with the highest purity using the proposed enzymatic method (ENZ). Economic and environmental analyses were also conducted for the proposed ENZ process, and the results were compared with those of the AUT process. The total capital investment of α-monostearin production, considering a projected capacity of 4950 t year?1 and 11% interest for the proposed ENZ process, was favorably 2.5 times lower than that of the AUT process, suggesting a promising investment opportunity. However, the total production costs showed unfavorable negative net present value (NPV) and return on investment (ROI) for the ENZ process and favorable positive NPV and ROI for the AUT process, indicating that the proposed venture is not profitable for α-monostearin production. However, the process can be profitable at improved operational stability of Novozym 435 up to 1 kg per 3-ton product. The carbon footprint was calculated on the basis of the given capacity and conditions of 50 and 656 t CO2 eq./year for the ENZ and AUT processes, respectively. The synthesis of α-monostearin using the proposed route can be considered a building block toward a cleaner large-scale production of α-monoglycerides.  相似文献   
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