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Role of the vagus nerve on the insulin-stimulating effect of pentagastrin. I. Effect of atropine in the dog.
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A simple method for the measurement of human gastric emptying: standardization of operative parameters.
No full textThe radioisotopic techniques used for the measurement of gastric emptying in man require complex and expensive scintiscanners or gamma-cameras. In this investigation, a simple method utilizing a single and inexpensive detector was evaluated; in addition, the suitability of 99Tcm sulphur colloid as a label for solid meals was assessed. The procedure was found to be accurate and its reproducibility high. The calculated absorbed dose to the gut was very low. Both in vitro and in vivo studies indicate that the radiocolloid used is a food non adsorbable marker for determining gastric emptying of solids. In a group of 50 healthy volunteers the emptying half-time (t1/2) ranged between 40 and 110 min, with a mean of 71.7 +/- 10.1 min, the male subjects exhibiting a significant lower t1/2 than females. In 5 volunteers with t1/2 within the normal range, the effect of drugs acting on gastric motility was evaluated. Hyoscine N-butyl bromide (20 mg) significantly delayed gastric emptying of solids, whereas metoclopramide (20 mg) was ineffective in these subjects. On the contrary, this drug was able to accelerate gastric emptying only in some patients with abnormally delayed emptying. On the whole, the method is simple, inexpensive and reproducible. It may be of great clinical value to investigate abnormalities of gastric function and to perform a better pharmacological approach to the medical treatment
Inhibition of gastric emptying by bombesin in man.
No full textBombesin, administered by intravenous infusion (5 ng . kg-1 . min-1) for 60 min, significantly delayed gastric emptying of solids in man and strongly potentiated the gastrin response to food. However, no correlation was found between the difference in the integrated gastrin response (to meal and to meal plus bombesin) and the degree of delay in emptying. The effect of the peptide is most likely connected with the strong contraction of the gastroduodenal junction pinpointed in previous investigations
Caerulein delays gastric emptying of solids in man.
No full textIntravenous administration of caerulein (40 ng/kg) delayed gastric emptying of solids in man. Radiological examinations demonstrated that the peptide causes a marked contraction of the pyloric sphincter and a relaxation of the gastric corpus and fundus. Therefore the effect of caerulein on gastric emptying may be considered as the result of different actions on the distal and proximal stomach. Furthermore pretreatment of the subjects with cimetidine did not modify the effect of caerulein indicating an action independent of the gastric hypersecretory effect of the peptide. The action of caerulein on gastric emptying must be kept in mind when the peptide is employed in the treatment of some pathological conditions
The effect of bombesin on gastric emptying of solids in man.
No full textIntravenous infusion of bombesin (5 ng.kg(-1). min(-1) significantly delayed gastric emptying of solids in man. The gastrin response to meal increased following administration of the peptide; however no correlation was found between the difference in gastrin response (to meal alone and to meal plus bombesin) and the degree of delay in emptying. In addition the behavior of intragastric pH after eating was not modified by bombesin infusion. All of these data suggest a direct effect of the peptide on gastric emptying, which was probably connected with the strong contraction of the antrum and pylorus observed in this and in previous investigations
Contrast-enhanced second-harmonic sonography in the detection of pseudocapsule in renal cell carcinoma
No full text“OBJECTIVE. Our purpose was to assess the capacity of contrast-enhanced second-harmonic sonography to detect a pseudocapsule in renal masses compared with conventional gray-scale sonography.
SUBJECTS AND METHODS. Thirty-two patients with 40 renal masses suspicious for renal cancer (mean diameter, 3.1 cm) were prospectively studied with contrast-enhanced second-harmonic sonography during IV administration of a second-generation sonographic contrast agent. The sonographic criteria for the presence of a pseudocapsule were a peritumoral hypoanechoic halo on conventional gray-scale imaging and a rim of perilesional enhancement, increasing in the tardive phase of the examination, on contrast-enhanced second-harmonic imaging. Multiphasic helical CT or dynamic MRI or both were performed in all patients.
RESULTS. Final diagnoses of the 40 renal masses were as follows: hemorrhagic cysts, five; angiomyolipomas, four; lymphomas, four; metastasis from lung cancer, one; and renal cell carcinomas (RCCs), 26. Histologic diagnosis of RCC was surgically obtained in all patients. Nephron-sparing surgery was performed in 12 of 26 RCCs, and radical nephrectomy was performed in the remaining 14. At pathologic examination, pseudocapsule was found in 14 (53.8%) of 26 RCCs. On conventional sonography, the presence of a pseudocapsule was detected in 3 of 14 RCCs (sensitivity, 21%). Sonographic contrast-enhanced harmonic imaging revealed the presence of pseudocapsule in 12 of 14 RCCs (sensitivity, 85.7%). In the remaining 12 RCCs with either absent or extensive neoplastic infiltration of pseudocapsule seen at pathologic evaluation, pseudocapsule was not visible on either conventional or contrast-enhanced second-harmonic sonography. The pseudocapsule was not visible in any of the 14 noncancerous renal masses on either conventional or contrast-enhanced sonography.
CONCLUSION. Sonographic contrast-specific imaging with a second-generation contrast agent is effective in improving the sonographic visualization of tumoral pseudocapsule. This finding could be useful both in the sonographic diagnosis and in the choice of conservative surgery for renal cell carcinoma. The potential role of second-harmonic contrast-enhanced sonography in the management of renal cell carcinoma should be investigated in larger series and compared with the findings of state-of-the-art MRI and CT.
Going Beyond Counting First Authors in Author Co-citation Analysis
Full text linkThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
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