Search PubMed⌕ Search

SEARCH · Search PubMed

Results for “extreme rays”

Search indexed PubMed citations on genomics, clinical trials, systematic reviews and public health. Explore titles, authors and supplied subject terms, then open the PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 271 records · Page 15Linked to original sources
PubMed1982

A basic X-ray service for a rural community in Southwestern Nigeria 1976-1980. A preliminary report.

The development of a basic X-ray service in a rural community in southwestern Nigeria is reviewed over a period of 5 years. Of the 3,278 examinations done during this period, chest X-rays constituted 56%. Most of the other examinations were requested on account of trauma of upper and lower extremities: 42 and 43%, respectively. Injuries to the elbow region constituted half of the X-rays for the upper extremities. There was an early upsurge of attendance for all X-rays reaching its peak at the first 2 years of the project, but a stable state was soon established within the subsequent 3 years. The non-chest examinations remained equally divided between the years under review. It is estimated that the introduction of the X-ray service has saved the community some 6,600 working days or 18 years in the 56-month period. This estimate excludes transportation for the accompanying relatives.

Health Services Needs and Demand↗
PubMed2004

Ectodermal dysplasia with tetramelic deficiencies and no mutation in p63: odontotrichomelic syndrome or a new entity?

The ectodermal dysplasias (ED) are a large and complex group of diseases characterized by anomalies of the ectoderm and its derivates, often associated with malformations in other organs. We report a patient with an ectodermal dysplasia affecting hair, teeth, and nails and malformations of all four extremities including absence of several rays in the hands and feet. This patient shares many similarities with odontotrichomelic syndrome, a rare ectodermal dysplasia syndrome that has so far only been described in three individuals. However, some differences exist and this patient might also represent a separate ectodermal dysplasia syndrome. p63, a gene that is mutated in a number of syndromes associated with ectodermal dysplasia and limb malformations, was considered a possible candidate gene. However, no mutation in p63 was identified.

Adult↗
PubMed1997

Three-dimensional flow-independent peripheral angiography.

A magnetization-prepared sequence, T2-Prep-IR, exploits T1, T2, and chemical shift differences to suppress background tissues relative to arterial blood. The resulting flow-independent angiograms depict vessels with any orientation and flow velocity. No extrinsic contrast agent is required. Muscle is the dominant source of background signal in normal volunteers. However, long-T2 deep venous blood and nonvascular fluids such as edema also contribute background signal in some patients. Three sets of imaging parameters are described to address patient-specific contrast requirements. A rapid, spiral-based, three-dimensional readout is utilized to generate high-resolution angiograms of the lower extremities. Comparisons with x-ray angiography and two-dimensional time-of-flight angiography indicate that this flow-independent technique has unique capabilities to accurately depict stenoses and to visualize slow flow and in-plane vessels.

Angiography↗
PubMed1990

Abnormal 67Ga uptake in a fibrosarcoma of the pericardium with malignant transformation.

A 31-year-old woman presented with general malaise, back pain, and edema of the lower extremities. A chest X-ray film showed an enlarged cardiac shadow and clear lung fields. A pericardial lesion with decreased activity on blood pool imaging and increased uptake on gallium citrate imaging displaced the heart upwards and to the left. The pericardial mass showed an inhomogeneous signal intensity on MRI and was large enough to obstruct the venous return by compressing the heart. At operation, the mass was found to originate from the pericardium and was histologically identified as a malignant fibrosarcoma. Twelve years previously, the patient had undergone an operation for the removal of a pericardial tumor which was histologically identified as a benign hemangioma. In view of the rarity of pericardial tumors, the present tumor is suspected to have undergone a transformation from benign hemangioma to malignant fibrosarcoma.

Adult↗
PubMed1988

Radiological features in congenital erythropoietic porphyria (Gunther's disease). Report of 3 cases.

Gunther's disease or congenital erythropoietic porphyria is a rare and severe disorder comprising cutaneous and haemolytic symptoms. Photocutaneous lesions are responsible for scleroderma-like calcifications and deformities of the extremities visible on X-rays. Hemolytic manifestations lead to diffuse major osteopenia. Soft tissue calcifications of the fingers can be seen even in young patients. One case reported here is the first illustration of intracranial calcifications located on dura-mater and calvarium.

Bone Diseases, Metabolic↗
PubMed2000

[Hypertrophic osteoarthropathy and thrombocytopenia in bronchial carcinoma].

SYMPTOMS: A 40-year-old woman presented with an arthritis of the knees and ankles, digital clubbing and thrombocytopenia. EXAMINATIONS: Blood tests proved an inflammatory reaction. Clinical findings were the above mentioned oligoarthritis and a periostitis of the long extremity bones. Chest X-ray showed a lung tumor. THERAPY: After surgical treatment of the lung cancer both arthritis and thrombocytopenia normalized. CONCLUSION: Hypertrophic osteoarthropathy is characterized by the combination of clubbing, arthropathy and periostitis. This paraneoplasia may be the presenting manifestation of occult malignancy. The diagnosis of hypertrophic osteoarthropathy should cause an intensive search of cancer. Further associated diseases are discussed.

Adenocarcinoma↗
PubMed2003

Grazing incidence small-angle X-ray scattering: an advanced scattering technique for the investigation of nanostructured polymer films.

Hamburg workshop on the "application of synchrotron radiation in chemistry"With grazing incidence small-angle X-ray scattering (GISAXS) the limitations of conventional small-angle X-ray scattering with respect to extremely small sample volumes in the thin-film geometry are overcome. GISAXS turned out to be a powerful advanced scattering technique for the investigation of nanostructured polymer films. Similar to atomic force microscopy (AFM), a large interval of length between molecular and mesoscopic scales is detectable with a surface-sensitive scattering method. While with AFM only surface topographies are accessible, with GISAXS the buried structure is also probed. Because a larger surface area is probed, GISAXS also has a much larger statistical significance compared to AFM. Due to the high demand on collimation, GISAXS experiments are based on synchrotron radiation. Nanostructures parallel and perpendicular to the sample surface observable in thin poly(styrene- block-isoprene) diblock copolymer films are presented as an example of the possibilities of GISAXS.

Journal Article↗
PubMed2002

Inguinal hernia as a rare manifestation of meconium peritonitis: report of a case.

The usual manifestations of meconium peritonitis confined to the inguinoscrotal region are soft hydroceles, hard nodules in the scrotum, and, occasionally, calcified nodules in the wall of a hernia sac, with or without calcification on abdominal X-ray. Inguinal hernia is an extremely rare manifestation of healed meconium peritonitis. An unusual presentation of meconium peritonitis encountered during hernia repair is described herein to alert the pediatric surgeon of this possibility to avoid unnecessary abdominal exploration.

Hernia, Inguinal↗
PubMed1996

High incidence of bites and stings by snakes and other animals among rubber tappers and Amazonian Indians of the Juruá Valley, Acre State, Brazil.

Among forest-dwelling Amazonian Indians and rubber tappers (seringueiros) of the Juruá valley in Acre State, north-western Brazil, snakebite is an important cause of morbidity and death. Overall, 13% of a surveyed population had been bitten during their lifetime. Seventeen per cent of Katukina Indians, but only 8% of Ashaninkas, had been bitten by snakes reflecting, perhaps, different levels of traditional knowledge of the forest and its dangers. Most bites occurred in the jungle or on jungle trails (56%), while people were working (41%) or walking (26%), and were inflicted on the feet (54%). Ninety per cent of bite victims received treatment, usually traditional (93%); the majority (80%) recovered fully. Mortality was estimated at about 400 deaths per 100,000 population per lifetime. Bites and stings from other venomous forest and river animals, especially the freshwater sting ray (Potamotrygon sp.), were also extremely common. One death from an ant bite was recorded.

Animals↗
PubMed2002

Kalisomes in corals: a novel KCl concentrating organelle?

Large membrane-bound inclusions were clearly visible within the gastrodermis and lipid-containing cells of planulae and settled larvae of the zooxanthellate coral, Pocillopora damicornis after fixation or freeze-substitution. We suggest that these inclusions may be a novel potassium (kalium) chloride concentrating organelle, for which we propose the name kalisome. The inclusions were more abundant in settled larvae than in planulae and were not present in mature polyps. In planulae of the azooxanthellate coral, Dendrophyllia sp. these inclusions were extremely rare. Quantitative X-ray microanalysis of freeze-substituted preparations showed that the inclusions in P. damicornis settled larvae contained very high, positively correlated, concentrations of K (2.5 mol x kg(-1)) and Cl (2.5 mol x kg(-1)). Lower concentrations of both K (1.2 mol x kg(-1)) and Cl (1.3 mol x kg(-1)) were detected in P. damicornis planulae, yet higher concentrations were measured in Dendrophyllia planulae (K=6.0 mol x kg(-1); Cl=5.1 mol x kg(-1)). No significant (P>0.05) differences in concentration were observed between inclusions in freeze-substituted and freeze-dried sections of planulae. Symbiotic algae (zooxanthellae) in P. damicornis planulae and settled larvae also contained deposits with high levels of K and Cl, but these were not positively correlated and no structures associated with them were retained by fixation. Significant (P<0.05) concentration differences were also observed between deposits in freeze-substituted and freeze-dried sections. However, similar to 'kalisomes,' zooxanthellae deposits were more abundant in settled larvae than planulae and absent in mature polyps. Higher concentrations of K and Cl were also detected in settled larvae (K=0.7 mol x kg(-1); Cl=1.1 mol x kg(-1)) in comparison to planulae (K=0.4 mol x kg(-1); Cl=0.5 mol x kg(-1)).

Animals↗
PubMed2002

Time-resolved atomic inner-shell spectroscopy.

The characteristic time constants of the relaxation dynamics of core-excited atoms have hitherto been inferred from the linewidths of electronic transitions measured by continuous-wave extreme ultraviolet or X-ray spectroscopy. Here we demonstrate that a laser-based sampling system, consisting of a few-femtosecond visible light pulse and a synchronized sub-femtosecond soft X-ray pulse, allows us to trace these dynamics directly in the time domain with attosecond resolution. We have measured a lifetime of 7.9(-0.9)(+1.0) fs of M-shell vacancies of krypton in such a pump-probe experiment.

Journal Article↗
PubMed2005

Direct observation of electron dynamics in the attosecond domain.

Dynamical processes are commonly investigated using laser pump-probe experiments, with a pump pulse exciting the system of interest and a second probe pulse tracking its temporal evolution as a function of the delay between the pulses. Because the time resolution attainable in such experiments depends on the temporal definition of the laser pulses, pulse compression to 200 attoseconds (1 as = 10(-18) s) is a promising recent development. These ultrafast pulses have been fully characterized, and used to directly measure light waves and electronic relaxation in free atoms. But attosecond pulses can only be realized in the extreme ultraviolet and X-ray regime; in contrast, the optical laser pulses typically used for experiments on complex systems last several femtoseconds (1 fs = 10(-15) s). Here we monitor the dynamics of ultrafast electron transfer--a process important in photo- and electrochemistry and used in solid-state solar cells, molecular electronics and single-electron devices--on attosecond timescales using core-hole spectroscopy. We push the method, which uses the lifetime of a core electron hole as an internal reference clock for following dynamic processes, into the attosecond regime by focusing on short-lived holes with initial and final states in the same electronic shell. This allows us to show that electron transfer from an adsorbed sulphur atom to a ruthenium surface proceeds in about 320 as.

Journal Article↗
PubMed2002

[Henoch-Schoenlein syndrome in an 80-year-old patient].

HISTORY AND CLINICAL FINDINGS: An 80-year old female patient, hospitalised with pneumonia and myocardial infarction, suddenly developed fever, dyspnoea, malaise, arthralgia and crampy abdominal pain. On the following day, she developed a petechial rash and on the 6 (th) day, macroscopic haematuria. On physical examination, the patient presented with a temperature of 40 degrees C, tachypnoea, tachycardia, and on auscultation coarse crepitations at the left lower base. The abdomen was tender upon deep palpation but bowel sounds were normal. Initially the petechial rash was located at the trunk, later progressing towards the extremities. INVESTIGATIONS: Chest X-ray and laboratory tests were consistent with left lower lobe pneumonia. The clinical picture was not consistent with any haematological causes, coagulopathy or any medication the patient was taking. Rheumatological blood tests (involving ANA, ANCA, rheumatoid factors) were basically negative. A skin biopsy revealed microvessel necrosis and IgA deposits, verifying Henoch-Schoenlein Purpura. An immune electrophoresis revealed a selective IgG-deficiency, which may explain the cause for the patient's recurrent pneumonias. COURSE: The patient recovered well under antibiotic treatment and skin lesions healed without sequelae. CONCLUSION: We present an unusual case of Henoch Schoenlein purpura associated with strictly petechial rash in an 80 year old female.

Aged↗
PubMed1987

[Clinical results of sonographic functional studies of lesions of the capsule and ligaments of the knee and ankle joint].

The authors conducted a clinical study to examine whether sonographic examinations of function would be a reliable alternative to x-ray films of the forced extreme joint position in lesions of capsule and ligament of the knee and ankle joints. Sonographic standard planes of section are defined and the results of the described examination methods in 200 patients are demonstrated. Ruptures of the external ligaments of the ankle joint as well as cruciate and collateral ligament instabilities at the knee joint are simple and safe to assess and document via sonography.

Ankle Injuries↗
PubMed1989

[Ligament lesions of the knee joint in childhood].

As a matter of principle, all lesions of the knee associated with haemarthrosis must be examined for internal injuries. Ligament ruptures are rare; usually, there are bony ligament tears that show up on x-ray film. Examination of ligament stability in children is useful only if the x-ray is negative and after the knee joint has been punctured under anaesthesia, and can be justified only in that case. Diagnosis is possible only by means of x-ray films taken in forced extreme joint position in two planes, with lateral comparison. Treatment of all non-dislocated ligament tears is conservative; slight dislocations can be tolerated in cruciate and capsular ligaments, since the epiphyseal cartilage is not affected. Surgery should be performed only if tears are considerably dislocated. Proximal tears of collateral ligaments are epiphyseal fractures that can be treated conservatively only if there is no dislocation; if they are dislocated, surgery is absolutely mandatory.

Child↗
PubMed1991

Mouse lymphoma cells that undergo interphase death show markedly increased sensitivity to radiation-induced DNA double-strand breakage as compared with cells that undergo mitotic death.

The relationship between radiation-induced DNA double-strand breakage (dsb) and reproductive death (clonogenicity) for two mouse lymphoma cell lines was compared with that for the fibroblast-like hamster cell line V79. One of the lymphoma lines (STRij-4-2.2), which undergoes rapid disintegration following cytotoxic insult, showed extreme sensitivity to gamma-ray or DNA-associated 125I decay-induced DNA dsb (7 +/- 1 125I decays per clonogenic lethal event). Surprisingly, the other lymphoma line (WEHI-22.1), which does not undergo rapid disintegration, was also much more sensitive to DNA dsb than were V79 cells (17 +/- 1 versus 61 +/- 2 125I decays per clonogenic lethal event). Ultrastructure, DNA degradation, and flow cytometric cell cycle data suggested that both lymphoma cell lines may undergo interphase death, but that the induction of this process in WEHI-22.1 may depend upon blockage in the G2 phase. It is concluded that there are marked differences between the radiation responses of lymphoma and fibroblast lines, that there may be different forms of radiation-induced interphase death, and that the low number of DNA dsb required to produce a clonogenic lethal event in cells undergoing interphase death could explain the radiosensitivity of organs such as ovary, testis and thymus.

Animals↗
PubMed1998

Rad51-deficient vertebrate cells accumulate chromosomal breaks prior to cell death.

Yeast rad51 mutants are viable, but extremely sensitive to gamma-rays due to defective repair of double-strand breaks. In contrast, disruption of the murine RAD51 homologue is lethal, indicating an essential role of Rad51 in vertebrate cells. We generated clones of the chicken B lymphocyte line DT40 carrying a human RAD51 transgene under the control of a repressible promoter and subsequently disrupted the endogenous RAD51 loci. Upon inhibition of the RAD51 transgene, Rad51- cells accumulated in the G2/M phase of the cell cycle before dying. Chromosome analysis revealed that most metaphase-arrested Rad51- cells carried isochromatid-type breaks. In conclusion, Rad51 fulfils an essential role in the repair of spontaneously occurring chromosome breaks in proliferating cells of higher eukaryotes.

Animals↗
PubMed1993

Cloning the RAD51 homologue of Schizosaccharomyces pombe.

The RAD51 gene of Saccharomyces cerevisiae encodes a RecA like protein, which is involved in the recombinational repair of double strand breaks. We have isolated the RAD51 homologue, rhp51+, of the distantly related yeast strain Schizosaccharomyces pombe by heterologous hybridization. DNA sequence analysis of the rhp51+ gene revealed an open reading frame of 365 amino acids. Comparison of the amino acid sequences of RAD51 and rhp51+ showed a high level of conservation: 69% identical amino acids. There are two Mlul sites in the upstream region which may be associated with cell cycle regulation of the rhp51+ gene. The rhp51+ null allele, constructed by disruption of the coding region, is extremely sensitive to X-rays, indicating that the rhp51+ gene, like RAD51, is also involved in the repair of X-ray damage. The structural and functional homology between rhp51+ and RAD51 suggests evolutionary conservation of certain steps in the recombinational repair pathway.

Amino Acid Sequence↗