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71.
With a focus directed on the potential diagnostic yield of tissue biopsy in suspected myocardial disease, transvascular endomyocardial biopsies were carried out prospectively in 130 patients. In 149 out of 153 consecutive procedures, where the number of associated major complications was less than 1%, King's bioptome and a specially designed radiopaque long introducer catheter were used. The rather thickwalled sheath had a conical tip which facilitated percutaneous entry and a preshaped distal bending which was particularly useful in the right ventricle for obtaining a steady and safe position in the direction of the interventricular septum. With respect to the histopathological information from an average of 4.2 biopsies per patient, a high clinical yield was gained in 28% of the patients, in the form of specific diagnoses and/or findings influencing subsequent therapy, and useful diagnostic information was gleaned from a further 53%. Thus, the procedure appears safe as a part of routine cardiac catheterization, and biopsy may contribute to a more accurate and clinically relevant classification of a substantial number of patients with suspected myocardial disease.  相似文献   
72.
The inhibitory effect of intravenous infusion of secretin (0.05 CU kg-1h-1) and somatostatin (60 pmol kg-1h-1), given alone or in combination, on pentagastrin-stimulated (100 ng kg-1 h-1) acid secretion was studied in 10 healthy subjects. Secretin inhibited acid secretion by 54% (p less than 0.05), and somatostatin inhibited by 70% (p less than 0.05). The combined infusion of secretin and somatostatin decreased acid output by 64% (p less than 0.05). The differences between the three groups were not significant (p greater than 0.05). Median plasma concentrations of secretin and somatostatin were of the same magnitude as seen after duodenal acidification. The present study did not demonstrate any interaction between secretin and somatostatin in the inhibition of gastric acid secretion.  相似文献   
73.
Cardiac muscarinic receptors activate an inwardly rectifying K+ channel, IK+Ach, via pertussis toxin (PT)-sensitive heterotrimeric G proteins (in heart Gi2, Gi3, or Go). We have used embryonic stem cell (ES cell)-derived cardiocytes with targeted inactivations of specific PT-sensitive α subunits to determine which G proteins are required for receptor-mediated regulation of IK+Ach in intact cells. The muscarinic agonist carbachol increased IK+Ach activity in ES cell-derived cardiocytes from wild-type cells, in cells lacking αo, and in cells lacking the PT-insensitive G protein αq. In cells with targeted inactivation of αi2 or αi3, channel activation by both carbachol and adenosine was blocked. Carbachol-induced channel activation was restored in the αi2- and αi3-null cells by reexpressing the previously targeted gene and guanosine 5′-[γ-thio] triphosphate was able to fully activate IK+Ach in excised membranes patches from these mutants. In contrast, negative chronotropic responses to both carbachol and adenosine were preserved in cells lacking αi2 or αi3. Our results show that expression of two specific PT-sensitive α subunits (αi2 and αi3 but not αo) is required for normal agonist-dependent activation of IK+Ach and suggest that both αi2- and αi3-containing heterotrimeric G proteins may be involved in the signaling process. Also the generation of negative chronotropic responses to muscarinic or adenosine receptor agonists do not require activation of IK+Ach or the expression of αi2 or αi3.  相似文献   
74.

Background and Objectives:

At present, we do not have a reliable method for the early diagnosis of colorectal anastomotic leakage (AL). We tested peritoneal flexible endoscopy through a port placed in the abdominal wall in the early postoperative course, as a new diagnostic method for detection of this complication and evaluated the suggested method for safety, feasibility, and accuracy.

Methods:

Ten swine were randomized into 2 groups: group A, colorectal anastomosis without leakage; and group B, colorectal anastomosis with leakage. A button gastrostomy feeding tube was inserted percutaneously into the peritoneal cavity. Colorectal anastomosis (with or without defect) was created 48 hours after the first operation. The swine were examined by peritoneal flexible endoscopy 8 and 24 hours after the colonic operation, by a consultant surgeon who was blinded to both the presence and the allocated location of the of the anastomotic defect.

Results:

None of the animals showed signs of illness 48 hours after the intraperitoneal gastrostomy tube placement. More than half of the anastomosis circumference was identified in 60 and 10% of the animals at endoscopy 8 and 24 hours, respectively, after the anastomosis was created. Excessive adhesion formation was observed in all animals, irrespective of AL. The sensitivity and specificity of endoscopy in detecting peritonitis 24 hours after AL were both 60%.

Conclusions:

Peritoneal endoscopy is a safe and simple procedure. Visualization of the peritoneal cavity in the early postoperative course was limited due to adhesion formation. Further studies are needed to clarify the accuracy of the procedure and to address additional methodological concerns.  相似文献   
75.
76.
The aim of this study was to examine the acute effect of tobacco smoke exposure and inhaled terbutaline on mucociliary clearance in 9 healthy smokers. It was based on a recently described method for scintigraphic visualization of the bronchi (bronchoscintigraphy). After an initial bronchoscintigram had been made by having the subjects inhale aerosolized 99mTc-albumin, they inhaled either terbutaline or placebo from a metered-dose inhaler. Subsequently, data acquisition for production of bronchoscintigrams was repeated at 10 min intervals for 120 min, and the mucociliary clearance was estimated from the movement of radioactivity in the series of bronchoscintigrams thus obtained. On two study days the subjects remained tobacco abstinent, while on two occasions they chain-smoked during the examination. Acute tobacco exposure resulted in an increased clearance rate in the lobar bronchi in 8 of the 9 smokers (p less than 0.03), while in the main bronchi and the trachea the effect was inconsistent. In all subjects terbutaline systematically increased the clearance rate in all visible bronchial structures compared to placebo (p less than 0.04). The combination of smoking and terbutaline caused a faster clearance rate in the lobar bronchi in most subjects than tobacco smoke or terbutaline alone. It is concluded that both acute tobacco exposure and terbutaline increase mucociliary clearance in healthy smokers.  相似文献   
77.
Taurine is often referred to as a semi‐essential amino acid as newborn mammals have a limited ability to synthesize taurine and have to rely on dietary supply. Taurine is not thought to be incorporated into proteins as no aminoacyl tRNA synthetase has yet been identified and is not oxidized in mammalian cells. However, taurine contributes significantly to the cellular pool of organic osmolytes and has accordingly been acknowledged for its role in cell volume restoration following osmotic perturbation. This review describes taurine homeostasis in cells and organelles with emphasis on taurine biophysics/membrane dynamics, regulation of transport proteins involved in active taurine uptake and passive taurine release as well as physiological processes, for example, development, lung function, mitochondrial function, antioxidative defence and apoptosis which seem to be affected by a shift in the expression of the taurine transporters and/or the cellular taurine content.  相似文献   
78.
Human glioblastoma multiforme (GBM) is an aggressive cancer with a very poor prognosis. Cripto‐1 (CR‐1) has a key regulatory role in embryogenesis, while in adult tissue re‐expression of CR‐1 has been correlated to malignant progression in solid cancers of non‐neuronal origin. As CR‐1 expression has yet to be described in cerebral cancer and CR‐1 is regulated by signaling pathways dysregulated in GBM, we aimed to investigate CR‐1 in the context of expression in GBM. The study was performed using enzyme‐linked immunosorbent assay (ELISA), Western blotting, polymerase chain reaction (PCR) and immunohistochemistry to analyze the blood and tissue from 28 GBM and 4 low‐grade glioma patients. Within the patient cohort, we found high CR‐1 protein levels in blood plasma to significantly correlate with a shorter overall survival. We identified CR‐1 in different areas of GBM tissue, including perivascular tumor cells, and in endothelial cells. Collectively, our data suggest that CR‐1 could be a prognostic biomarker for GBM with the potential of being a therapeutic target.  相似文献   
79.
BACKGROUND Liver cancer is the fifth most common cancer and the second cause of cancerrelated deaths worldwide.Transarterial chemoembolization(TACE)is the best treatment of intermediate hepatocellular carcinoma(HCC).Doxorubicin is the most commonly used drug despite a low level of evidence.AIM To compare the objective response rate of idarubicin-based TACE(Ida-TACE)against doxorubicin-based TACE(Dox-TACE)in intermediate stage HCC.METHODS Between January 2012 and December 2014,all patients treated with TACE at our academic hospital were screened.Inclusion criteria were patients with Child-Pugh score A or B,a performance status below or equal to 1,and no prior TACE.Either lipiodol TACE or drug-eluting beads TACE could be performed with 10 mg of idarubicin or 50 mg of doxorubicin.Each patient treated with idarubicin was matched with two doxorubicin-treated patients.The TACE response was assessed by independent radiologists according to the mRECIST criteria.RESULTS Sixty patients were treated with doxorubicin and thirty with idarubicin.There were 93%and 87%of cirrhotic patients and 87%and 70%of Child-Pugh A in the doxorubicin and idarubicin groups,respectively.The median number of HCC per patient was two in both groups with 31%and 26%of single nodules in doxorubicin and idarubicin groups,respectively.Objective response rate after first TACE was 76.7%and 73.3%(P=0.797)with 41.7%and 40.0%complete response in doxorubicin and idarubicin groups,respectively.Progression-free survival was 7.7 mo in both groups,and liver transplant-free survival was 24.9 mo and 21.9 mo in doxorubicin and idarubicin groups,respectively.Safety profiles were similar in both groups,with grade 3-4 adverse events in 35%of Dox-TACE and 43%of Ida-TACEs.CONCLUSION Ida-TACE and Dox-TACE showed comparable results in terms of efficacy and safety.Ida-TACE may represent an interesting alternative to Dox-TACE in the management of patients with intermediate stage HCC.  相似文献   
80.
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