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941.
In this study, we sought to validate the importance of p63, CK5/CK6, CK7, and surfactant-A (SP-A) to classify 42 non-small cell lung cancers in autopsy and surgical resection specimens and to study the usefulness of these markers in distinguishing between squamous cell carcinomas and adenocarcinomas because of their different implications regarding treatment and prognosis. All adenocarcinoma cases were negative for p63; 9 (56.2%) of 16 were CK5/CK6 positive, 16 (94.1%) of 17 were CK7 positive, and 4 (26.6%) of 15 were SP-A positive. In squamous cell carcinoma, 1 case was CK7 and SP-A positive and 14 (77.8%) of 18 were p63 positive. The latter appears to be useful in differentiating squamous cell carcinoma from adenocarcinoma of the lung in small biopsies without keratinization or glandular differentiation; thus, for advanced-stage cases, where there is no possibility of surgical resection and the treatment of choice is radiotherapy plus chemotherapy, we would be able to differentiate between the two histological types, establishing then a different therapy. 相似文献
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Vorstand und AG Angeborene Herzfehler/Kinderherzchirurgie der DGTHG 《The Thoracic and cardiovascular surgeon》2006,54(2):73-77
The "Working Group for Congenital Heart Surgery and Pediatric Heart Surgery" of the German Society for Thoracic and Cardiovascular Surgery (GSTCVS) has analysed and recommended structures for congenital heart surgery departments in Germany. The document was worked out according to a similar paper approved earlier by the European Association for Cardio-thoracic Surgery (EACTS). The "Working Group" unifies the majority of cardiac surgeons involved in congenital heart surgery in Germany. Current structures of cardiac centers vary. Therefore the aim of this document is to elucidate additional structural needs for both highly specialized institutions and those for standard care. Specialized centers should allow for treatment of newborns and adult patients with congenital heart disease, include implementation of assist devices and transplantation, possess research facilities and ensure highest standards of education and training. Standard care units do not necessarily need to cater for the above mentioned spectrum. However, the evaluation of quality of care should be given priority in all centers involved in care of patients with congenital heart disease. Data acquisition and transfer must be guaranteed to both the GSTCVS and EACTS in order to ensure national and international comparison of surgical results. This may also give further guidance for improved patient care. 相似文献
945.
Daniela Fernanda de Freitas Carlos Eduardo Dobrovolskin PortoElisabeth Pizzamiglio Vieira Maria Elisa Pereira Bastos de Siqueira 《Journal of pharmaceutical and biomedical analysis》2010
A three-phase, liquid-phase microextraction using a hollow fibre (HF-LPME) combined with high performance liquid chromatography-fluorescence detection (HPLC-FL) was developed for the analysis of fluoxetine (FLX) and its active metabolite, norfluoxetine (NFLX), in human plasma. An HF-LPME system using a disposable 7-cm polypropylene porous hollow fibre, 5 mL of alkaline plasma solution (donor phase), n-hexyl ether (extraction solvent) and 20 mM hydrochloric acid (acceptor phase) was used in the extraction. The method was validated after optimisation of several parameters that influence LPME efficiency. A reverse-phase LiChrospher 60 RP-Select B column (125 mm × 4 mm, 5 μm particle size) was used with 0.005 M sodium acetate buffer (pH 4.5) and acetonitrile at a 50:50 (v/v) as the mobile phase at a flow rate of 0.6 mL min−1. In these conditions satisfactory chromatographic resolution and efficiency for the analytes were obtained. Fluorescence detection at 230 nm excitation wavelength and 290 nm emission wavelength was performed. Linearity over a range of 5–500 ng mL−1, with determination coefficients (R2) of 0.9999 and 0.9962 for FLX and NFLX, respectively, was established. Venlafaxine was used as the internal standard for both analytes. Extraction recoveries from plasma samples were 70.9% for FLX and 59.7% for NFLX. The intra-day coefficients of variation (CVs) were below 5.4%, and inter-day CVs were below 13.0%, for both analytes at concentrations of 20, 80 and 160 ng mL−1. HF-LPME extraction followed by HPLC-FL detection for FLX and NFLX analyses demonstrated excellent sample clean-up and selectivity. This method was simple, cheap, and easy to perform, yielding substantial analytes enrichment. The method was applied to the analysis of samples from 12 patients under fluoxetine treatment and proved suitable for routine therapeutic drug monitoring for this antidepressant. 相似文献
946.
Monique B Moss Mariana A Siqueira Giovanni E Mann Tatiana MC Brunini Antônio C Mendes‐Ribeiro 《Clinical and experimental pharmacology & physiology》2010,37(2):167-172
1. Systemic arterial hypertension (SAH) is a major independent risk factor for cardiovascular disease. The physiopathology of SAH is multifactorial, complex and remains to be elucidated. Nitric oxide (NO) is an important regulator of vascular and haemostatic functions. The cationic amino acid l ‐arginine serves as the substrate for NO synthases (NOS) and arginase, an enzyme of the urea cycle. We have previously reported inhibition of l ‐arginine transport in erythrocytes and platelets in hypertension. 2. The aim of the present study was to investigate the l ‐arginine–NO pathway and urea cycle in platelets and their role in platelet function and systemic inflammatory responses in SAH patients. The expression and activity of NOS and arginase in platelets, platelet aggregation and plasma levels of C‐reactive protein (CRP) were evaluated in 20 SAH patients and 18 age‐matched healthy volunteers. 3. There was a reduction of NOS activity in hypertensive patients that was associated with activation of platelet aggregability induced by collagen, but not by ADP. Platelets from SAH patients exhibited compensatory overexpression of inducible NOS, but not endothelial NOS. Intraplatelet arginase activity in SAH patients was not affected, but systemic concentrations of CRP were increased compared with controls. 4. It is likely that diminished NO bioavailability in SAH contributes to cardiovascular complications. Our findings may provide the basis for developing new therapeutic approaches for the treatment of hypertension. 相似文献
947.
Terra MB Barros HM Stein AT Figueira I Jorge MR Palermo LH Athayde LD Gonçalves MS Spanemberg L Possa MA Daruy Filho L Da Silveira DX 《Comprehensive psychiatry》2006,47(6):463-467
BACKGROUND: Although the frequency of social phobia is high among alcoholic patients, this anxiety disorder is often neglected because treatment tends to be focused exclusively on alcohol dependence. METHODS: A total of 300 hospitalized alcoholic patients were interviewed using Structured Clinical Interview for the Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition and Liebowitz Social Anxiety Scale as well a questionnaire to check the use of medication for social phobia among alcoholics and the relationship between social phobia and alcohol use. RESULTS: A prevalence of 30.6% was found for specific phobia, 24.7% for social phobia, 22.2% for anxiety disorder induced by alcohol, 19.3% for generalized anxiety disorder, 5% for obsessive-compulsive disorder, 4.6% for posttraumatic stress disorder, and 2% for panic disorder with agoraphobia. Social phobia preceded alcohol dependence in 90.2% of the patients. The frequency of the use of medication for social phobia among social phobic alcoholics was 20.3%. CONCLUSIONS: The study confirms the high prevalence of anxiety disorders among alcoholics, particularly of social phobia. It also suggests that social phobia precedes alcohol dependence but shows that the use of medication for social phobia is still infrequent. Further studies are required to check if the failure to identify this comorbidity can make the recovery of alcoholics even more difficult. 相似文献
948.
de Carvalho Borges B Carnio EC Elias LL Antunes-Rodrigues J Branco LG da Rocha MJ 《Brain research》2006,1115(1):83-91
This study examined whether electrolytic ablation of the periventricular anteroventral third ventricle (AV3V) region would affect the hypothalamic activation and the increase of hypophysial hormone secretion induced by systemic injection of lipopolysaccharide (LPS) in rats. LPS significantly increased the number of cells showing Fos immunoreactivity in the paraventricular (PVN) and supraoptic (SON) nuclei of the hypothalamus (P<0.05) and also increased plasma levels of vasopressin, oxytocin, adrenocorticotropin and corticosterone (P<0.05). AV3V lesion significantly reduced LPS-induced Fos immunoreactivity (P<0.05) and vasopressin and oxytocin secretion (P<0.05). Elevations in adrenocorticotropin but not in plasma corticosterone after LPS were affected by prior AV3V lesions. These findings demonstrate that LPS-induced Fos expression in the PVN and SON, and hypophysial hormone secretion is dependent on the integrity of the AV3V region. 相似文献
949.
The lumbrical-interossei comparison study is commonly employed in the electrodiagnosis of carpal tunnel syndrome. Placement of the recording electrodes relies on anatomic landmarks as the muscles being recorded cannot be seen or palpated. To determine the optimal active electrode location, 15 controls and 5 patients were studied using a grid of 12 electrodes placed over the lateral palm. Amplitudes, rise-times, and latencies of the responses at each location were measured. The lowest control latency difference was located in the lateral mid-proximal palm (mean 0 ms, upper range of 0.5 ms). This location also had the highest lumbrical amplitude and rise-time. More distal in the palm, the mean latency difference increased to 0.5 ms with an upper range of 0.9 ms. When performing the lumbrical-interossei comparison study, it is essential to place the active recording electrode in the optimal location. Failure to do so will result in an increased number of false-positive studies. 相似文献
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