assessment of colonic transit time (ctt) in patients with chronic constipation

Introduction Arterial transit time is a critical parameter for calculating cerebral blood flow (CBF) using arterial spin labeling (ASL). Arterial transit time is also a novel physiological parameter that is uniquely measured by ASL and may have independent clinical significance for detecting CBF that is maintained through collateral flow sources. Most ASL experiments acquire data at a single de...

The system mean transit time (T,^) of the impulse response function describing contrast material transit through the coronary circulation was determined from serial digital angiographic images. The linearity, reproducibility, and relations with regional myocardial perfusion and conventional time-density curve parameters, time to peak concentration (TPC), and exponential washout rate (k) were as...

About 20% of the population suffer from constipation. For the common types of functional constipation, idiopathic and IBS related constipation, the proportion of women is about 80-90%. It is important to structure the management of this large patient group. The duration of symptoms is of relevance. In general, a long history allows for more restricted investigations, and the management can be f...

local bus network is the most popular transit mode and the only available transit mode in the majority of cities of the world. increasing the utility of this mode which increases its share from urban trips is an important goal for city planners. timetable setting as the second component of bus network design problem (network route design timetable setting vehicle assignment crew assignment) hav...

BACKGROUND Contrast-enhanced ultrasonography (CEUS) is a novel imaging modality to estimate microvascular perfusion. We aimed to assess renal cortical microcirculatory changes by CEUS during pharmacologically or mechanically induced modifications of renal blood flow (RBF) in experimental animals. METHODS We implanted invasive transit-time Doppler flow probes and a vascular occluder around the...

Introduction The blood transit time from arterial spin labeling plane to capillaries in the imaging slice (referred to as “tissue transit time”) decreased during neuronal activation in humans (1), while it appeared no changes during somatosensory stimulation in rats (2). Since a tissue transit time is shorter in rats compared to humans, shortening blood transit time may not be detectable with a...

The probability that an existing planetary transit is detectable in one’s data is sensitively dependent upon the window function of the observations. We quantitatively characterize and provide visualizations of the dependence of this probability as a function of orbital period upon several observing strategy and astrophysical parameters, such as length of observing run, observing cadence, lengt...

Aims: The present study is to investigate the value of multi-slice spiral computed tomography (MSCT) in the differentiation of benign and malignant solitary pulmonary nodule (SPN). Methods: A total of 21 patients with benign SPN and 21 patients with malignant SPN were included in the present study. MSTC perfusion imaging characteristics and parameters were analyzed. For imaging analysis, shapes...