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41.
目的对良恶性胸腔积液(胸液)病理细胞学、癌胚抗原(CEA)和铁蛋白(FT)检测进行对比研究。方法比较分析48例癌性胸液和32例结核性胸液的临床表现、影像学表现、血清及胸液CEA、FT测定结果。结果 48例癌性胸液为血性40例,32例结核性胸液为血性8例,恶性胸液CEA、FT比其血清CEA、FT明显升高(P<0.05),同结核性胸液比也较之升高(P<0.05)。结论病理细胞学检查可确诊癌性胸液,CEA、FT检测可以提高该病的检出率。 相似文献
42.
Sankaran Subramanian Ken-Ichi Yamada Akira Irie Ramachandran Murugesan John A Cook Nallathamby Devasahayam Gootzian M Van Dam James B Mitchell Murali C Krishna 《Magnetic resonance in medicine》2002,47(5):1001-1008
A novel method, called relaxo-oximetry, for rapid spatially resolved in vivo measurements of oxygen concentration using time-domain radiofrequency (RF) electron paramagnetic resonance (EPR) is described. Time-domain data from triaryl methyl (TAM)-based single-electron contrast agents were processed by systematic deletion of the initial time points to arrive at T2*-weighted discrimination of signal amplitudes. In experiments involving phantoms, the line widths [ approximately (T2*)(-1)] increased as a function of oxygen, and the slope (line width/pO(2)) was the same for both absorption- and magnitude-mode line shapes. Line widths derived from T2* weighting and the computed pO(2) values agreed favorably with the measured ones from phantoms of known oxygen tension. In vivo relaxo-oximetry was performed on C3H mice, and it was found that the liver was more hypoxic than the kidneys. For tumors, 2D oxygen maps were generated while the animal breathed room air or Carbogen(R) (95% O(2)/5% CO(2)). Carbogen(R) enhanced oxygen concentration within the tumor, and the pO(2) histograms showed considerable heterogeneity. Clark electrode oxygen measurements on organs and tumors were in good agreement with tissue oxygen measurements done by relaxo-oximetry. Thus, from a single spatial image data set, pO(2) measurements can be done noninvasively by relaxo-oximetry, and 3D imaging can be performed in less than 3 min. 相似文献
43.
人体硬组织替代材料表面键合白蛋白方法的研究 总被引:1,自引:1,他引:0
采用BrCN活化法。探讨了在羟基磷灰石(HA)、生物玻璃陶瓷(BGC)和羟基聚磷酸钙钠(HP)表面结合白蛋白的条件。结果表明,在一定条件下羟基聚磷酸钙钠可以和白蛋白形成共价键结合,而BGC和HA则难以形成这种结合。 相似文献
44.
Kim M Pugarelli J Miller TL Wolfson MR Dodge GR Shaffer TH 《Pediatric pulmonology》2012,47(8):763-770
Ultrasound imaging allows in vivo assessment of tracheal kinetics and cartilage structure. To date, the impact of mechanical ventilation (MV) on extracellular matrix (ECM) in airway cartilage is unclear, but an indication of its functional and structural change may support the development of protective therapies. The objective of this study was to characterize changes in mechanical properties of the neonatal airway during MV with alterations in cartilage ECM. Trachea segments were isolated in a neonatal lamb model; ultrasound dimensions and pressure-volume relationships were measured on sham (no MV; n = 6) and MV (n = 7) airways for 4 hr. Tracheal cross-sections were harvested at 4 hr, tissues were fixed and stained, and Fourier transform infrared imaging spectroscopy (FT-IRIS) was performed. Over 4 hr of MV, bulk modulus (28%) and elastic modulus (282%) increased. The MV tracheae showed higher collagen, proteoglycan content, and collagen integrity (new tissue formation); whereas no changes were seen in the controls. These data are clinically relevant in that airway properties can be correlated with MV and changes in cartilage ECM. MV increases the in vivo dimensions of the trachea and is associated with evidence of airway tissue remodeling. Injury to the neonatal airway from MV may have relevance for the development of tracheomalacia. We demonstrated active airway tissue remodeling during MV using an FT-IRIS technique which identifies changes in ECM. 相似文献
45.
Eastman CJ 《Pathology》2012,44(2):153-159
The high global prevalence of iodine deficiency and autoimmune thyroid disorders and the mental and physical consequences of these disorders creates a huge human and economic burden that can be prevented, in large part, by early detection and appropriate preventative or therapeutic measures. The availability of sophisticated, sensitive and accurate laboratory testing procedures provides an efficient and effective platform for the application of screening for these disorders. Measurement of urine iodine concentration (UIC) in school children or pregnant women is the recommended indicator for screening populations for iodine deficiency. The severity of the iodine deficiency is classified according to the UIC. Measurement of serum thyrotropin (TSH) as an indicator for population iodine deficiency is used only in neonates and is supplementary to UIC screening. Other indicators such as goitre rates, thyroid function and serum thyroglobulin levels are useful adjunctive but not frontline process indicators. The human and economic benefits of screening for congenital hypothyroidism by measurement of heel-prick TSH have been well documented and justify its universal application. Using this measurement for monitoring population iodine intake is recommended by the World Health Organization but further validation is required before it can be universally recommended. Subclinical thyroid dysfunction is readily detected by current highly sensitive serum TSH assays and its prevalence appears to increase with age, varies with iodine intake and ethnicity and may occur in up to 20% of older age people. Subclinical hyperthyroidism is the less common disorder and screening cannot be justified because of its low prevalence and minimal or insignificant clinical effects. The argument for screening for subclinical hypothyroidism in middle-aged and older women is stronger but lacks evidence of benefit from randomised controlled trials or cost benefit analyses of therapeutic intervention, so it cannot currently be recommended. The publication of recent Clinical Practice Guidelines for management of thyroid disease in pregnancy from the American Endocrine Society and American Thyroid Association provide persuasive arguments for early detection and treatment of overt and subclinical hypothyroidism to prevent obstetric complications and potential neurocognitive disorders in the offspring. Given the indisputable benefits of therapy, the sooner thyroid dysfunction is detected, before or as early as possible in gestation, the more likely there will be a better outcome. Because of the limitations of targeted case detection in women at risk of subclinical hypothyroidism, there has been a gradual shift in opinion to universal TSH screening of all women as soon as practicable in pregnancy. While a positive association exists between the presence of anti-thyroid antibodies and increased pregnancy loss, universal screening of all pregnant women for underlying autoimmune thyroid disease is difficult to justify until there is evidence of beneficial outcomes from randomised controlled trials. Vigorous and liberal targeted case detection remains the recommended strategy to address this problem. 相似文献
46.
Robert Brüll Raquel Maria Karsten Rode 《Macromolecular chemistry and physics.》2010,211(20):2233-2239
The quantity of absorbance of linear polarized light depends for a given wavelength on the angle between an absorbing transition moment vector and the electric vector of the polarized light. Fraser used this relationship to interpret the infrared dichroism in axially oriented polymers. This model can be extended to calculate the orientation in three dimensions by transforming the Fraser's equation into a P2‐Legendre polynomial. As a result the orientation in three directions—fx, fy, and fz—can be calculated directly from the individual absorbances measured with an electric vector along the axes of interest, the structural absorbance A0 of the sample, and the angle of the transition moment vector in reference to the chain axis. Applying the f values into ‘Hermans’ Orientation function', it becomes possible to calculate the average angle of the chain axis with reference to the axes of interest.
47.
Jianli Wang Yilin Song Cheng Zhang Zhibin Ye Hui Liu Myong‐Hoon Lee Dehai Wang Jianbing Ji 《Macromolecular chemistry and physics.》2008,209(14):1495-1502
A novel alternating copolymer of sulfonated poly(ether ether ketone‐benzimidazole)s (SPEEK‐BI) was synthesized by polycondensation of aromatic bisphenol containing benzimidazole and a mixture of sulfonated and non‐sulfonated difluorobenzophenones. By varying the amount of two difluorobenzophenones, the ratio of sulfonic acid unit to imidazole base was controlled straightforwardly. The polymer structure was characterized by 1H NMR and IR spectroscopy. Two different methods of ion exchange capacity measurement supported a strong inter‐ and intra‐molecular interaction between acid and base units, which resulted in an improved mechanical strength as well as avoiding phase separation. Tough membranes with good mechanical stability in hot water (80 °C) and alcohol were obtained by solution casting, which is potential for applications in polymer electrolyte membrane fuel cells and membranes for separation of liquids or gases.
48.
49.
《Diabetes & metabolism》2020,46(6):496-503
AimWe aimed to evaluate the association between serum thyroid stimulating hormone (TSH) levels, within the reference range, and the histological severity of nonalcoholic fatty liver disease (NAFLD), and whether this association was modulated by the patatin-like phospholipase domain-containing 3 (PNPLA3) rs738409 polymorphism.Materials and methodsWe enrolled 327 euthyroid individuals with biopsy-proven NAFLD, who were subdivided into two groups, i.e., a ‘strict-normal’ TSH group (TSH level 0.4 to 2.5 mIU/L; n = 283) and a ‘high-normal’ TSH group (TSH level 2.5 to 5.3 mIU/L with normal thyroid hormones; n = 44). Logistic regression analyses were performed to assess the association between TSH status and presence of nonalcoholic steatohepatitis (NASH) after stratifying subjects by PNPLA3 genotypes.ResultsCompared to strict-normal TSH group, patients with high-normal TSH levels were younger and had a greater prevalence of NASH and higher histologic NAFLD activity score. After stratifying by PNPLA3 genotypes, the significant association between high-normal TSH levels and presence of NASH was restricted only to carriers of the PNPLA3 G risk allele and remained significant even after adjustment for potential confounding factors (adjusted-odds ratio: 3.279; 95% CI: 1.298–8.284; P = 0.012).ConclusionIn euthyroid individuals with biopsy-proven NAFLD, we found a significant association between high-normal TSH levels and NASH. After stratifying by PNPLA3 rs738409 genotypes, this association was observed only among carriers of the PNPLA3 G risk allele. 相似文献
50.
《Neuro-Chirurgie》2023,69(5):101478
ObjectivePituitary abscess is an often misdiagnosed, rare clinical disorder. To improve diagnostic accuracy and the efficacy of surgical and antibiotic therapy for patients with pituitary abscess, herein, we retrospectively reviewed 15 patients who presented with pituitary abscesses from 2005 to 2022.DesignRetrospective study.PatientsFifteen patients underwent transsphenoidal surgery and received antibiotic treatment.MeasurementsComplete details regarding medical history, clinical manifestations, laboratory examinations, imaging studies, and treatment strategies were obtained for all patients.ResultsMost patients presented with hypopituitarism and headaches, while some presented with fever, visual disturbances, and diabetes insipidus (DI). Abscesses showed significant annular enhancement post gadolinium injection. In most patients, pituitary abscess can be cured via microscopic or endoscopic drainage of the abscess followed by antibiotic treatment. Complete cure of pituitary abscess was observed in nine patients, with six cases of prolonged hypopituitarism and only one case of recurrence. Long-term hormone replacement therapy was effective in the postoperative management of hypopituitarism.ConclusionsThe typical manifestations of pituitary abscess include hypopituitarism and headaches; the presence of an enhanced ring at the edge of the mass on contrast-enhanced magnetic resonance images (MRI) is highly suggestive of pituitary abscess. We recommend antibiotic treatment for 4–6 weeks postoperatively, based on the results of bacterial cultures or metagenomic next-generation sequencing (mNGS). 相似文献