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1.
Neuroimaging in Pineal Tumors   总被引:4,自引:0,他引:4  
F Reis  MD  AV Faria  MD  PhD  VA Zanardi  MD  PhD  JR Menezes  MD  F Cendes  MD  PhD  LS Queiroz  MD  PhD 《Journal of neuroimaging》2006,16(1):52-58
BACKGROUND AND PURPOSE: The authors report radiological findings in 11 tumors in the pineal region, which were histologically diagnosed as germinomas, pineocytomas pineoblastomas, ependymomas, teratomas, and astrocytomas. METHODS: Computed tomography (CT) was performed in seven patients and magnetic resonance imaging (MRI) was performed in all patients. RESULTS: CT showed a solid or solid/cystic mass with variable contrast enhancement. MRI showed a heterogeneous mass, with hypointense signal on T1 and iso/hyperintense signal on T2-weighted images (WI) and gadolinium enhancement. Extension to adjacent structures occurred in five patients and spread through the cerebral spinal fluid (CSF) in two. CONCLUSIONS: Pineal region tumors have no pathognomonic imaging pattern. MRI and CT are complementary in diagnosis and are important to determine localization, extension, and meningeal spread.  相似文献   
2.
Exogenous surfactant therapy (EST) in surfactant-deficient premature infants has been shown to improve lung compliance, decrease morbidity, and improve survival. Reports have demonstrated that newborns with congenital diaphragmatic hernia (CDH) have lung compliance, pressure-volume curves, and hyaline membrane formation resembling those changes seen in surfactant deficient premature newborns. We hypothesize that EST may also benefit infants with CDH. All high risk cases of prenatally diagnosed CDH at Children's Hospital of Buffalo from November 1988 to February 1991 were prospectively evaluated for EST. In those families who chose to participate, the surfactant preparation, Infasurf (100 mg/kg), was instilled into the newborn's lungs prior to the first breath. The remainder of the perinatal, neonatal, and surgical care was performed in a routine manner. Three high-risk prenatally diagnosed newborns with left CDH were treated with EST. All showed signs of decreased pulmonary compliance, but could still be adequately oxygenated and ventilated. Surgical correction was performed after stabilization and all required patch closures. Two of the three infants suffered no life-threatening episodes of pulmonary hypertension and all survived. These infants had many known indicators for poor outcome in CDH with an expected survival of less than 20%. We believe that EST in these neonates with CDH contributed to their survival with minimum morbidity. These results suggest that surfactant replacement for the high-risk neonate with CDH warrants further consideration and a randomized clinical trial is being planned.  相似文献   
3.
This study was designed to investigate the expression of cyclooxygenase (COX)-2 in ovarian serous tumors (benign, borderline tumors, and carcinomas) and primary peritoneal serous carcinomas. Cases diagnosed between 1995 and 2001 were reviewed; 47 benign tumors, 6 borderline tumors, and 39 carcinomas were examined, as well as 12 normal ovaries that served as controls. Blocks were stained with anti COX-2 polyclonal antibody and staining was graded qualitatively. The staining intensity was assessed as weak (score of 1), moderate (score of 2), or strong (score of 3). Normal ovarian and tubal epithelium, inclusion cysts, benign serous tumors, and borderline tumors had a uniform score 3 staining pattern. Serous ovarian carcinomas had variable staining scores, tending to correlate with the level of tumor differentiation. Well-differentiated carcinomas had more intense COX-2 staining than poorly differentiated carcinomas, which had only weak COX-2 staining. The degree of COX-2 staining was not significantly related to overall survival. In conclusion, COX-2 expression is present in serous tumors, including benign tumors, borderline tumors, and carcinomas. Similar to the findings in other neoplasms, COX-2 expression is strongest in well-differentiated tumors and is much less evident in those that are poorly differentiated. The clinical utility of these findings is related to the potential role of nonsteroidal anti-inflammatory drugs, which are COX-2 inhibitors, in treating and/or preventing some forms of ovarian carcinoma.  相似文献   
4.
5.
Deregulation of apoptosis is involved in prostate cancer development and progression. This study involved an immunohistochemical "profiling" of prostate tissue specimens from patients who underwent prostatectomy for localized prostate cancer, to identify apoptosis-specific alterations associated with premalignant precursor lesions. Prostate tissue was pathologically evaluated, and areas of benign acini, high-grade prostate intraepithelial neoplasia (HGPIN), and prostate cancer were identified. Immunohistochemical analysis was performed to determine the expression of p27Kip1, a key cell cycle regulator, transforming growth factor (TGF)-beta receptor II (TbetaRII), a critical signaling effector of TGF-beta; Smad4, a downstream intracellular effector of TGF-beta signaling; p53, a key apoptosis regulator; and prostate-specific antigen (PSA), a clinical marker of prostate cancer. The apoptotic index of the same cell populations was determined using the transferase-mediated digoxigenin-tagged 16-desoxy-uridine-triphosphate nick end labeling assay. Our findings indicate a significant reduction in p27Kip1 immunoreactivity in HGPIN (P<0.0001) and prostate cancer (P<0.0001) compared with the benign tissue. A significant down-regulation was detected in TbetaRII expression in HGPIN and prostate cancer compared with benign prostatic hyperplasia (BPH)(P<0.001). A significant decrease was also observed in Smad4 levels in HGPIN and prostate cancer compared with BPH (P<0.001). Evaluation of the incidence of apoptosis revealed a significant decrease in the apoptotic index among the epithelial cell populations in HGPIN and a further decrease in prostate carcinoma (P<0.01). This reduced apoptotic index correlated with a significant increase in p53 immunoreactivity in the prostatic carcinoma foci. Prostate cancer cells exhibited strong nuclear staining for p53 compared with adjacent HGPIN (P<0.05) and the benign lesions of the same prostate specimens (P<0.05). A significant reduction in PSA immunostaining was detected in HGPIN and prostate carcinoma foci compared with the benign glandular epithelia (P<0.001). These results further define deregulation of TGF-beta signaling effectors as a molecular basis for loss of apoptotic control contributing to the development of prostate tumors. Identification of apoptotic regulators in precursor premalignant lesions may have prognostic significance in disease progression as well as therapeutic value for targeting prostate cancer.  相似文献   
6.
Myo-inositol transport in the central nervous system   总被引:18,自引:0,他引:18  
  相似文献   
7.
Summary: Hydrophobically modified poly(acrylic acid) was synthesized using 3‐pentadecylcyclohexylamine (3‐PDCA), which was in turn synthesized from 3‐pentadecylphenol, one of the components of cashew‐nut shell liquid (CNSL), a renewable resource material. 1H NMR spectra confirmed the incorporation of 3‐PDCA onto PAA and a series of HMPs with three different molar concentrations, viz ? 3, 5 and 7 mol‐% of 3‐PDCA, were synthesized. An increase in viscosity with increasing hydrophobic content was observed by rheological measurements. The critical association concentrations were determined using an Ubbelohde viscometer and a controlled stress rheometer. The stability of HMPs towards temperature and shear was studied. Rheological measurements showed that there was a steady increase in viscosity with increase in hydrophobe content due to the formation of reversible networks. These polymers exhibited gel‐like behavior at low concentrations (≥2 wt.‐%) with an apparent yield stress (ca. 10 Pa) and showed shear thinning properties (non‐Newtonian). However, below a critical concentration, c [η], they showed Newtonian behavior.

ηsp of unmodified and modified PAA‐Na at various polymer concentrations.  相似文献   

8.
Summary Levels of three enzymes, leucine aminopeptidase (LAP), N-acetyl--D-glucosaminidase (NAG), and -glucuronidase (BGA) were measured in the urine of patients receiving hematologically toxic doses of iproplatin (a) with or (b) without pretreatment hydration. The maximum post-treatment increases in the levels of each of the enzymes were compared between these two groups of patients. In addition, the maximum increases in urinary enzyme levels in iproplatin-treated patients were compared with those in patients treated with 40 mg/m2 cisplatin, a known nephrotoxic agent.Increases in LAP levels after cisplatin treatment in the periods studied are significantly higher than those after iproplatin treatment (P0.05). No differences were found in the increases in BGA and NAG levels between iproplatin treatment and cisplatin treatment. No differences were found in the increases in levels of any of the enzymes between patients receiving iproplatin with pretreatment hydration and no prior hydration.The work reported in this paper was supported in part by grant CA-21071 from USPHS NCI and by Bristol Myers Co.  相似文献   
9.
目的:医疗服务价格改革对完善医疗服务合理定价,合理体现医务人员劳务价值,提高医务人员薪酬水平具有重要意义。方法:基于利益传导的视角,以医务人员劳务价值的体现为中介,采用定量研究方法,实证检验医疗服务价格对医务人员薪酬水平的影响。结果:医疗费用规模对医务人员薪酬水平有着显著的正向影响,但在门诊医疗和住院医疗二者间存在异质性,主要体现在劳务价值在医疗费用中的差异方面。结论:应持续深化医疗服务价格改革,提高医务人员薪酬水平。  相似文献   
10.
近年来随着各种新镇痛药的问世 ,牙科治疗中的疼痛问题有了新的解决办法。本研究采用随机双盲法观察了拔牙术前应用曲马多缓释片 (下称曲马多 )的镇痛效果 ,并对拔牙术后疼痛的相关因素作多元回归分析。对象与方法1.对象 :10 4例门诊需拔牙的患者 ,其中男性 46例、女性 5 8例 ;年龄 18~ 86岁。根据随机双盲原则分为曲马多组 42例、索米痛组 30例和安慰剂组32例 (用葡萄糖酸钙片 )。2 .方法 :由专门一位医生 (不知患者已用何种药物 )按常规方法拔牙 ,以减少技术上的差异 ,并告诉患者拔牙前使用了止痛药以避免干扰性心理因素的作用。各组在术…  相似文献   
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