[Information substances in the primate brain--distribution and ontogeny].
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Comparing the distributions of blood pressure in different populations it has been found that the log-normal distribution gave the best summary of the data. The geometric mean and the coefficient of variation of the underlying blood pressure distribution were the most informative statistics. Using this blood pressure distribution, a model is discussed for the change in blood pressure with age and between populations. These changes are consistent with an environmental factor, such as salt intake, affecting the position of the mean of the blood pressure distribution and with a gradient of susceptibility within a population.
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The object of the present investigation was to measure the thickness distribution of the subchondral plate of the tibial plateau. The data were obtained by computerised image analysis of serial sections. The measured values revealed a marked difference in the thickness between the various regions of the joint surface. Thinner zones (100-300 microns) are found in the peripheral region near the margin of the tibial plateau. Thickness maxima (up to 1500 microns and more) are to be seen at the centres of the joint surfaces. The relationship between the thickness distribution of the subchondral plate and information about the stress distribution of this particular joint surface support the conclusion that the morphology of the subchondral plate of the tibial plateau is determined by the function of the joint.
Multichannel Urethral Pressure Profilometry (MCUPP) is a method used to get more information on the pressure distribution within the female urethra. This information may be of value in the diagnostic work up of women with urinary incontinence. Different systems are used for this technique. The pump is an important part of such a system. The catheter is perfused with water pumped through the side hole of the catheter. Air bubbles inside one or more of the eight channels alter the elastic properties of the catheter making the results unreliable. In daily urodynamic practice it is important that the system is patient and user-friendly, is quick to set up, and the performance of measurements is easy. For this reason a new type of pump was developed that is able to produce a pressure stable continuous flow through the eight channels of the catheter. The problem of air bubbles has been solved and different measurements can be performed serially in a short time. The system currently used by us is described.
5706 canine urinary stones were analyzed by means of infrared spectroscopy from 1984-1996. The stones were sent in together with epidemiologic data (breed, age, sex, localisation of the stones, type of stone removal, stone frequency etc.) by more than 800 veterinarians from Germany, the Netherlands, Austria, and Switzerland. Irrespective of stone type, urinary stones were observed in almost all breeds, but small breeds like dachshound, poodle, terrier, schnauzer, and pekingese have a higher tendency to form stones. With 59.5% struvite is the most frequent stone type, followed by cystine with 15.5%. Cystine stones are becoming less frequent during the observation time, whereas the share of calcium oxalate (14.2%) and ammonium urate (6.0%) stones remains unchanged. The latter stone types are found predominantly in specific breeds. The stone formation appears predominantly at the age of 7. Male dogs form stones twice as often as female dogs. 98% of the stones were located in the lower urinary tract. About 90% of the urinary stones required surgical treatment.
Since the discovery that lithium (Li) is efficacious for the treatment of manic depressive illness, the brain Li distribution of mammals treated with lithium has been of interest. However, the spatial relationship of lithium in the brain regions to its function remains largely unknown. Knowledge of Li distribution in the brain is necessary to localize its action in the brain. Both the therapeutic and neurotoxic side effects of Li are centered mainly in the central nervous system and hence there is considerable interest in understanding the extent of lithium penetration into the central nervous system. The mechanism by which neurotoxic side effects are generated is not known and may, in part, be related to the particular distribution of lithium in the brain. The regional specificity in lithium's brain distribution could underlie important steps on its action. Li levels in various brain regions for autopsied rats and humans have been reported. However, many results are conflicting due to ion redistribution at death or during sample preparation. A direct nondestructive measurement of Li levels in the brain where the drug exerts its effects is certainly desirable. Because magnetic resonance technique can be used to observe Li, it can be an appropriate method to monitor and map the distribution in the brain. The application of MR technology to rat brain regions has provided information on lithium distribution in a non-invasive manner. The earlier development work at lower field strengths provided brain lithium information at high dose of Li administration. Here we demonstrate the feasibility of quantitative spectroscopic imaging on rat brain under therapeutic doses.
Direct information on the distribution of a drug requires measurements in various tissues. Such data have until now been obtained in animals, or have indirectly been calculated from plasma measurements in humans using mathematical models. Here we suggest the use of positron emission tomography (PET) as a method to obtain direct measurements of drug distribution in the human body. The distribution in body and brain of vinpocetine, a neuroprotective drug widely used in the prevention and treatment of cerebrovascular diseases, was followed after oral administration. Vinpocetine was labelled with carbon-11 and radioactivity was measured by PET in stomach, liver, brain and kidney in six healthy volunteers. The radioactivity in blood and urine as well as the fractions of [(11)C]vinpocetine and labelled metabolites in plasma were also determined. After oral administration, [(11)C]vinpocetine appeared immediately in the stomach and within minutes in the liver and the blood. In the blood the level of radioactivity continuously increased until the end of the measurement period, whereas the fraction of the unchanged mother compound decreased. Radioactivity uptake and distribution in the brain were demonstrable from the tenth minute after the administration of the labelled drug. Brain distribution was heterogeneous, similar to the distribution previously reported after intravenous administration. These findings indicate that vinpocetine, administered orally in humans, readily enters the bloodstream from the stomach and gastrointestinal tract and, consequently, passes the blood-brain barrier and enters the brain. Radioactivity from [(11)C]vinpocetine was also demonstrated in the kidneys and in urine, indicating that at least a part of the radioactive drug and labelled metabolites is eliminated from the body through the kidneys. This study is the first to demonstrate that PET might be a useful, direct and non-invasive tool to study the distribution and pharmacokinetics of orally administered labelled CNS drugs in the living human body.
The association of mammographic parenchymal patterns of the breast with breast cancer risk has been studied extensively but there is little information about the distribution of different patterns in populations at different risks for breast cancer. Such information could be obtained if a risk-free method of breast examination were available that could be applied to the general population. We have evaluated real time ultrasound for this application by comparing the parenchymal pattern as assessed by mammography with the extent of echogenicity in the breast on ultrasound examination in 102 subjects. Subjects were examined by both methods, the mammographic and ultrasound images independently classified, and the proportion of the breast occupied by radiological density or ductal prominence compared with the extent of echogenic areas on ultrasound. These two methods of classifying mammographic parenchymal patterns were found to be strongly correlated. Real time ultrasound may therefore be useful in the epidemiological study of mammographic pattern and breast cancer risk.
A systematic mosquito taxonomic study in Korea was established by Lee in 1971. Since then, many species have been recorded as new to Korea. However, much of this taxonomic information has been distributed in a number of scientific publications. This work attempts to combine this information into a single document, as well as to synthesize revised taxonomic synonyms of species occurring in Korea. Four species, Culex vorax, Culex kangi, Aedes kobayashii and Culiseta kanayamensis listed in our previous paper, are synonyms of Culex halifaxii, Culex jacksoni, Aedes alektorovi and Culiseta bergrothi, respectively. Culex annulus is a misidentified species of Culex pseudovishnui. The subspecies Culex pipiens quinquefasciatus and subgenus Mansonia (Coquillettidia) were treated as full species and genus respectively in a catalog of the mosquitoes of the world. However, not all current authors agree to those specific and generic treatment. Based on available publications the total number of mosquito species recorded in Korea is now 52 representing 9 genera. Forty-five of these 52 are confirmed species with preserved specimen representation. As collection of specimen continues, there is a possibility that representative of 7 unconfirmed species will be found. I hope this paper will provide useful information for entomology workers who are interested in mosquito taxonomy in Korea.
The amount of published information is increasing exponentially, and recent technologic advances have created systems whereby mass distribution of this information can occur at an infinite rate. This is particularly true in the broad field of medicine, as the absolute volume of data available to the practicing clinician is creating new challenges in the management of relevant information flow. Evidence-based medicine (EBM) is an information management and learning strategy that seeks to integrate clinical expertise with the best evidence available in order to make effective clinical decisions that will ultimately improve patient care. The systematic approach underlying EBM encourages the clinician to formulate specific and relevant questions, which are answered in an iterative manner through accessing the best available published evidence. The arguments against EBM stem from the idea that there are inherent weaknesses in research methodologies and that emphasis placed on published research may ignore clinical skills and individual patient needs. Despite these arguments, EBM is gaining momentum and is consistently used as a method of learning and improving health care delivery. However, if EBM is to be effective, the clinician needs to have a critical understanding of research methodology in order to judge the value and level of a particular data source. Without critical analysis of research methodology, there is an inherent risk of drawing incorrect conclusions that may affect clinical decision-making. Currently, there is a trend toward using secondary pre-appraised data rather than primary sources as best evidence. We review the qualitative and quantitative methodology commonly used in EBM and argue that it is necessary for the clinician to preferentially use primary rather than secondary sources in making clinically relevant decisions.
BACKGROUND: Sub-national figures providing information about the wealth of the population are useful in defining the spatial distribution of both economic activity and poverty within any given country. Furthermore, since several health indicators such as life expectancy are highly correlated with household welfare, sub-national figures allow for the estimation of the distribution of these health indicators within countries when direct measurement is difficult.We have developed methods that utilize spatially distributed information, including night-time light imagery and population to model the distribution of income per capita, as a proxy for wealth, at the country and sub-national level to support the estimation of the distribution of correlated health indicators. RESULTS: A first set of analysis are performed in order to propose a new global model for the prediction of income per capita at the country level. A second set of analysis is then confirming the possibility to transfer the country level approach to the sub-national level on a country by country basis before underlining the difficulties to create a global or regional models for the extrapolation of sub-national figures when no country data set exists. CONCLUSIONS: The methods described provide promising results for the extrapolation of national and sub-national income per capita figures. These results are then discussed in order to evaluate if the proposed methods could not represent an alternative approach for the generation of consistent country specific and/or global poverty maps disaggregated to some sub-national level.
The Wigner distribution function (WDF) does not require the analysed signals to be stationary within the time segment used for analysis, and instantaneous frequency (IF) information can be obtained from it. Because of the influence of the cross-power of the signal components, however, the interpretation of the IF results is physically clear only for monocomponent signals with infinite data lengths. The IF results for multicomponent signals also suffer from spike problems and are quite unstable even when the signal-to-noise ratio is high. It is suggested that a "pseudo-instantaneous mean frequency," which uses the positive part of the WDF to follow the power distribution changes among frequency components, is used as a simple and rapid way to track frequency changes of Doppler signals. Simulation results show that the pseudo-instantaneous mean frequency does not have the same spike problems and gives stable and relatively accurate information about frequency changes when the sampling frequency is properly chosen.
OBJECTIVES: To obtain accurate spatial information on cancer distribution with a novel prostate biopsy regimen. METHODS: From 2003 to 2005, 265 patients underwent a three fan-shaped biopsy (3FSB) technique of 12 to 14 cores and sextant biopsy (SB) simultaneously. When both techniques had positive findings, and radical prostatectomy was performed, the concordance among the positive biopsy locations of the SB, 3FSB, and the combination of both (the reference standard biopsy [RSB]), the proven locations of cancer, and the presence of extracapsular extension and positive surgical margins was calculated. RESULTS: A total of 41 patients were selected, and 74 locations (left and right apex, left and right lobe) had cancer. Of these, 61 were confirmed by RSB, 58 by 3FSB, and 43 by SB with a sensitivity of 95%, 78%, and 58%, respectively. The sensitivity at the apical location was consistently greater for the 3FSB at 68% (19 of 28) compared with 40% (11 of 28) for all proven apical positive localizations and 100% (19 of 19) compared with 58% (11 of 19) for the RSB. The receiver operating characteristic analysis showed 78% accuracy for 3FSB and 68% accuracy for SB compared with the RSB. At the apex, the 3FSB and SB revealed positive surgical margins with a sensitivity of 1 and 0.4, specificity of 0.067 and 0.4, positive predictive value of 0.263 and 0.182, and negative predictive value of 1 and 0.667, respectively. CONCLUSIONS: The 3FSB had a great ability to find cancer in the gland, especially at the apex.
Systems Biology requires comprehensive systematic data on all aspects and levels of biological organization and function. In addition to information on the sequence, structure, activities and binding interactions of all biological macromolecules, the creation of accurate predictive models of cell behaviour will require detailed information on the distribution of those molecules within cells and the ways in which those distributions change over the cell cycle and in response to mutations or external stimuli. Current information on subcellular location in protein databases is limited to unstructured text descriptions or sets of terms assigned by human curators. These entries do not permit basic operations that are common to other biological databases, such as measurement of the degree of similarity between the distributions of two proteins, and they are not able to fully capture the complexity of protein patterns that can be observed. The field of location proteomics seeks to provide automated, objective high-resolution descriptions of protein location patterns within cells. Methods have been developed to group proteins into statistically indistinguishable location patterns using automated analysis of fluorescence microscope images. The resulting clusters, or location families, are analogous to clusters found for other domains, such as protein sequence families. Preliminary work suggests the feasibility of expressing each unique pattern as a generative model that can be incorporated into comprehensive models of cell behaviour.
BACKGROUND: Medico legal autopsies can be valuable sources of information about the distribution of causes of reported deaths, particularly in homicidal cases. The present study provides information regarding the homicidal deaths due to firearm injuries in the district of Peshawar, NWFP, Pakistan. METHODOLOGY: This descriptive study was conducted over the period of the year 2004. Data were collected from the autopsy records of the Department of Forensic Medicine, Khyber Medical College Peshawar and included all reported unnatural deaths from urban and rural areas of district Peshawar on whom autopsies were conducted in the department. RESULTS: Homicidal deaths constituted 77.7% (492/633) of all autopsies for the year 2004. Of 492 homicidal deaths, a vast majority of 452 (91.87%) were caused by firearm injuries. Among these, the male to female ratio was 5.5:1. The most common firearm weapon (418/452, 92.5%) were high velocity rifled weapons (Kalashnikov, rifles, pistols), followed by low velocity rifled weapons (18/452, 3.98%) and shotguns (16/452, 3.54%). A total of 956 injuries were found in various body areas, giving an average of over two injuries per person. The head, face and neck sustained the highest injuries (257, 26.9%), followed by the chest (248, 25.9%) and abdomen (149, 15.6%); the extremities, buttocks and genitalia together sustained 302 (31.6%) injuries. CONCLUSION: The vast majority of reported homicides in Peshawar are caused by firearm injuries, which bring up issues related to possession of firearms and changes in cultural attitudes towards use of firearms, if a decrease in firearm-related homicides is desired.
Nuclear magnetic resonance (NMR) offers the possibility to determine moisture profiles in porous building materials. Moreover, the relaxation of the nuclear magnetic resonance signal can provide additional information on the water distribution in the microstructure. For mortar, it is shown that the transverse relaxation yields information on the distribution of water in the gel pores and capillary pores. Moisture profiles and relaxation were measured during water absorption. The effect of the drying treatment on the microstructure and the water absorption was investigated.