Your browser doesn't support javascript.
loading
Show: 20 | 50 | 100
Results 1 - 8 de 8
Filter
Add more filters










Database
Language
Publication year range
1.
Biol Lett ; 14(9)2018 09.
Article in English | MEDLINE | ID: mdl-30185609

ABSTRACT

Large-scale analysis of the fossil record requires aggregation of palaeontological data from individual fossil localities. Prior to computers, these synoptic datasets were compiled by hand, a laborious undertaking that took years of effort and forced palaeontologists to make difficult choices about what types of data to tabulate. The advent of desktop computers ushered in palaeontology's first digital revolution-online literature-based databases, such as the Paleobiology Database (PBDB). However, the published literature represents only a small proportion of the palaeontological data housed in museum collections. Although this issue has long been appreciated, the magnitude, and thus potential significance, of these so-called 'dark data' has been difficult to determine. Here, in the early phases of a second digital revolution in palaeontology--the digitization of museum collections-we provide an estimate of the magnitude of palaeontology's dark data. Digitization of our nine institutions' holdings of Cenozoic marine invertebrate collections from California, Oregon and Washington in the USA reveals that they represent 23 times the number of unique localities than are currently available in the PBDB. These data, and the vast quantity of similarly untapped dark data in other museum collections, will, when digitally mobilized, enhance palaeontologists' ability to make inferences about the patterns and processes of past evolutionary and ecological changes.


Subject(s)
Databases, Factual/statistics & numerical data , Fossils , Invertebrates , Animals , California , Museums/statistics & numerical data , Oregon , Paleontology/methods , Washington
2.
MAGMA ; 10(1): 27-34, 2000 Feb.
Article in English | MEDLINE | ID: mdl-10697223

ABSTRACT

The purpose of this study was to scrutinize the ability of magnetic resonance imaging (MRI)-performed measurements to compare arterial flow patterns in patients with peripheral arterial occlusive disease (PAOD), healthy volunteers (HV) and endurance athletes (EA). MRI blood flow data were partially repeated with Doppler ultrasound (DUS) with a view to a methodical comparison. Additionally, pulse wave velocity was assessed with the MUFF technique. For this purpose, MRI-performed flow measurements were performed in the common femoral artery in 21 patients with PAOD, in 34 HV and in 12 EA. The analysis included maximum flow velocities (MFV), velocity/time profile (VTP), pulse wave velocity (Vpulse), and vessel diameter (VD). In addition, MFV and VD were observed by DUS in most individuals. The results revealed a significant change regarding arterial blood flow characteristics in patients compared with HV and EA, with respect to the span between the peak positive and negative blood flow velocity in the femoral artery. The pulse wave velocity in patients was markedly elevated compared with healthy individuals. Furthermore, a complete, characteristic change in the VTP could be observed in patients. The methodical comparison between DUS and MRI showed a good correlation. Multi-slice Fourier flow data have indicated markedly increased pulse wave velocity in PAOD patients. Changes in the arterial blood flow can be clearly observed with MRI. In the future, this might offer a noninvasive possibility not only for the evaluation of the stage of the disease, but also for the detection of early, pre-clinical stages of atherosclerosis.


Subject(s)
Arterial Occlusive Diseases/physiopathology , Arteries/physiology , Arteriosclerosis/physiopathology , Magnetic Resonance Imaging/methods , Sports/physiology , Adult , Aged , Arteries/physiopathology , Blood Flow Velocity , Diastole , Female , Fourier Analysis , Heart Rate , Humans , Male , Middle Aged , Physical Endurance , Reference Values , Regression Analysis , Systole , Ultrasonography, Doppler
3.
Eur Radiol ; 8(2): 295-7, 1998.
Article in English | MEDLINE | ID: mdl-9477286

ABSTRACT

A 69-year-old diabetic male with salmonella bacteremia developed hypovolemic shock and swelling of the neck. A CT examination revealed massive mediastinal hemorrhage extending into the neck soft tissues caused by false aneurysm rupture of the descending thoracic aorta. Aortography showed continuous extravasation from a large leak at the medial side of the descending thoracic aorta. Although surgical intervention was immediately performed, the patient died 3 weeks later from multiple-organ failure. In this report, CT and angiographic findings of mycotic aneurysm rupture are presented and a review is given.


Subject(s)
Aneurysm, Infected/diagnostic imaging , Aortic Aneurysm, Thoracic/diagnostic imaging , Aortic Rupture/diagnostic imaging , Aneurysm, False/diagnostic imaging , Aneurysm, False/microbiology , Aneurysm, Infected/microbiology , Aortic Aneurysm, Thoracic/microbiology , Aortic Rupture/microbiology , Bacteremia/complications , Humans , Male , Middle Aged , Salmonella Infections/complications , Salmonella typhimurium , Tomography, X-Ray Computed
4.
J Comput Assist Tomogr ; 21(6): 887-91, 1997.
Article in English | MEDLINE | ID: mdl-9386277

ABSTRACT

PURPOSE: The purpose of this study was to point out MR characteristics of non-Hodgkin lymphomas of the orbits and the paranasal sinuses and the benefit of fat-suppressed contrast-enhanced sequences. METHOD: The MR images of 16 patients with lymphoma of the orbits and the paranasal sinuses were retrospectively analyzed for signal intensity, contrast enhancement, bone destruction, and mass effect. The findings were confirmed by means of biopsy (Stage IE disease) or follow-up imaging after chemotherapy (Stage IV disease). RESULTS: MRI clearly delineated the extension of the lymphomas. On the T1-weighted images, the signal intensity of the lymphoma was hypointense compared with the gray matter of the brain in 12 cases and intermediate in 4 cases. The T2-weighted fast SE images showed a hyperintense signal in 12 cases, intermediate in 3 cases, and even hypointensity in 1 case. All lesions enhanced after intravenous Gd-DTPA administration, reliably visible in the T1-weighted fat-suppressed sequences but not visible in three cases in the T1-weighted SE sequences. Bony wall destruction was evident in cases with paranasal but never in isolated orbital lymphoma. CONCLUSION: While extension of lymphoma can be accurately described by MRI, a specific diagnosis is not achievable on the basis of signal intensities and enhancement patterns alone. Therefore, at least in cases of suspected Stages IE and IIE, biopsy proof is needed. Fat-suppressed contrast-enhanced sequences possess the highest detection rate and should therefore always be applied.


Subject(s)
Lymphoma, Non-Hodgkin/diagnosis , Magnetic Resonance Imaging , Orbital Neoplasms/diagnosis , Paranasal Sinus Neoplasms/diagnosis , Adolescent , Adult , Aged , Aged, 80 and over , Contrast Media , Female , Gadolinium DTPA , Humans , Male , Middle Aged , Retrospective Studies
5.
J Clin Anesth ; 9(6): 499-500, 1997 Sep.
Article in English | MEDLINE | ID: mdl-9278840

ABSTRACT

Bilateral sequential pulmonary atelectasis occurred during median sternotomy for metastasis resection in a 19-year-old women with asthma. Collapse was secondary to mucus plugging and resolved with mechanical ventilation, suctioning, and treatment for bronchospasm.


Subject(s)
Asthma/complications , Lung Neoplasms/surgery , Osteosarcoma/surgery , Pulmonary Atelectasis/etiology , Thoracotomy/adverse effects , Adult , Female , Humans , Lung Neoplasms/secondary , Osteosarcoma/secondary
8.
Gynecol Invest ; 7(4): 213-21, 1976.
Article in English | MEDLINE | ID: mdl-992481

ABSTRACT

In vitro perfusion studies of glucose transport in the human placenta show saturation kinetics at high glucose concentrations and competitive inhibition of glucose transfer by the nonmetablizable glucose analog 3-O-methyl-alpha-D glucopyranoside. These characteristics provide further evidence that glucose is transported by a facilitated diffusion process in the human placenta.


Subject(s)
Glucose/metabolism , Methylglucosides/metabolism , Methylglycosides/metabolism , Placenta/metabolism , Biological Transport , Female , Humans , Maternal-Fetal Exchange , Perfusion , Pregnancy
SELECTION OF CITATIONS
SEARCH DETAIL
...