Statistical problems in clinical trials frequently involve fitting regression lines when the underlying data are categorical or ordinal response variables. Usually an ad hoc a priori quantification is used to assign values to these ordinal responses. For pain intensity data collected in analgesic trials, the usual approach is to set none equal to 0, mild equal to 1, moderate equal to 2, and severe equal to 3. While this scheme has been generally accepted, on the basis that for similar clinical trials reasonably similar results are obtained by different investigators, concern exists that the distances between pain scores are probably not equal. A method is presented for quantifying categorical responses so that the resulting scores maximize the simultaneous fit of the dose-response regression lines. The optimal scores derived by this technique may then be used in a bioassay analysis to estimate the relative potency of 2 compounds. As illustrative examples, this method was applied to data from 2 clinical trials and the results were compared to the usual method.

Analysis of Variance↗

PubMedDate not supplied

Two small intrahepatic cholangiocarcinomas with different sonographic appearances.

We report on 2 cases of small intrahepatic (or peripheral) cholangiocarcinomas initially detected by sonography and completely resected. The lesions had a peripheral hypoechoic component and a central isoechoic or hyperechoic component. One had posterior acoustic shadowing on sonography, and the other did not. Comparison with pathologic findings in both cases indicated that severe fibrotic changes may have caused the posterior acoustic shadowing. This finding is extremely rare. We found only 1 previously reported case of cholangiocarcinoma accompanied by acoustic shadowing.

Acoustics↗

PubMedDate not supplied

Biliary cystadenoma with mesenchymal stroma of the liver: correlation between unusual MR appearance and pathologic findings.

We reported a case of the biliary cystadenoma of the liver. The cystic mass had lobulation and septation and showed marked hyperintensity on T1-weighted images and hypointensity on T2-weighted images; MR findings were very unusual for cystadenoma. The content of the cystic mass was jelly-like, thick mucinous fluid without intracystic hemorrhage. We concluded that these unusual signal intensities of the cyst were due to hyperproteinous mucinous fluid.

Adenoma, Bile Duct↗

PubMedDate not supplied

Localization of GTPase-activating protein-(GAP) like immunoreactivity in mouse cerebral regions.

GTPase-activating protein is known to regulate the conversion between ras-GTP and ras-GDP. We studied the basal expression of GTPase-activating protein-like immunoreactivity in mouse cerebral regions using a polyclonal anti-GTPase-activating protein antibody. Cells with GTPase-activating protein-like immunoreactivity were distributed in frontal cortical layers IV and V, and in the parietal cortex, piriform cortex, amygdaloid area, septum, lateral thalamus, and hypothalamus. The GTPase-activating protein-like immunoreactivity was also observed in fiber-like structures in the caudate putamen, stria terminalis, internal capsule, and medial forebrain bundle, and around CA2 pyramidal cells in Ammon's horn. These results imply that GTPase-activating protein is constitutively expressed in mouse brain regions and may have physiological functions in specific neuronal pathways in the brain.

Animals↗

PubMedDate not supplied

A simple measurement of parotid salivary flow using material quick absorber.

We applied Material Quick Absorber (Inami Co Ltd, Tokyo, Japan), a small triangular paper strip made mainly from viscose and used for fluid absorption during surgery, to collect right resting parotid saliva directly from Stensen's orifice and estimated nonstimulated parotid salivary flow by weighing the saliva absorbed in a given period of time. We assayed this method in 53 patients with dry mouth and/or throat and in 115 healthy young and elderly control subjects. The median salivary flow rates in male and female patients were 18 mg/min (almost equal to 0.018 mL/min) and 11 mg/min, respectively, significantly lower (P less than .05 for men, P less than .01 for women) than those obtained from young male (36 mg/min) and female (34 mg/min) controls and consistent with previously reported physiologic flow rates obtained by means of the "cup method." Although the median flow rate for elderly male controls (35 mg/min) was rather close to that of young male or female controls, there was no significant difference in flow rates between elderly male controls and male patients. On the other hand, in female control subjects, a significant decrease (P less than .05) in salivary flow was shown with aging. Repeated 3-minute measurements (eight times at 5- to 6-minute intervals) with this method in 10 healthy younger male volunteers showed that the coefficient of variance in the same subject ranged from 14.1% to 57.2% and that the larger the mean flow rate the smaller the coefficient of variance (P less than .05 by simple regression analysis).(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗