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2.
Aviat Space Environ Med ; 65(9): 851-7, 1994 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-7818456

RESUMO

The health and performance of spacecraft crews can be adversely affected by contaminants present in the respirable air. Contaminants originate from hardware offgassing, crew and microbial metabolism, use of utility chemicals, leakage from fluid systems and payload experiments, and from electrical overheating. The quality of Shuttle air is measured by collecting contaminants in evacuated cylinders or on sorbent resin for later ground-based analysis by gas chromatography (GC) and GC mass spectrometry (MS). The results of those analyses are presented for 28 missions, including 5 Spacelabs which were flown in the payload bay of the Shuttle. The major contaminants were relatively nontoxic alcohols (ethanol, isopropanol), ketones (acetone, diacetone alcohol), alkanes, halocarbons (Halon 1301, Freon 113), and siloxanes. Occasionally, more toxic contaminants, such as methanol, acetaldehyde, and tetrachloroethene, were present at low concentrations (below 1 mg/m3). The contaminant concentrations measured in spacecraft air were compared to spacecraft maximum allowable concentrations (SMAC's) which are set to protect the crew from adverse health effects or performance decrements. Aggregate toxicity assessments (T values) of the contaminants present during each mission, calculated by summing the ratios of measured concentrations to each contaminant's SMAC, showed that air quality consistent met the criterion that the T value be less than 1.


Assuntos
Poluição do Ar em Ambientes Fechados/análise , Voo Espacial , Astronave , Álcoois/análise , Alcanos/análise , Cromatografia Gasosa , Cetonas/análise , Concentração Máxima Permitida , Volatilização
3.
Aviat Space Environ Med ; 64(11): 992-9, 1993 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-8280047

RESUMO

Degradation of air quality in the Space Shuttle environment through chemical contamination and high solid-particulate levels may affect crew performance and health. A comprehensive study of the Shuttle atmosphere was undertaken during the STS-40 (Spacelab Space Life Sciences 1) and STS-42 (Spacelab International Microgravity Laboratory 1) missions to determine the effectiveness of contaminant control procedures by measuring concentrations of volatile organic compounds and analyzing particulate matter trapped on air filters. Analysis of volatile contaminants showed that the air was toxicologically safe to breathe during both missions with the exception of one period during STS-40 when the Orbiter Refrigerator/Freezer was releasing noxious gases into the middeck. Chemical analyses of selected particles collected on air filters facilitated their positive identification. Trace amounts of rat hair and food particles were found in the STS-40 Spacelab filters; a trace amount of soilless plant-growth media was detected in the STS-42 Spacelab filter. The low levels of particles released from these Spacelab experiments indicate that containment measures were effective.


Assuntos
Poluição do Ar em Ambientes Fechados/análise , Voo Espacial , Álcoois/análise , Aldeídos/análise , Hidrocarbonetos/análise
8.
Scott Med J ; 35(5): 147-8, 1990 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-2255898

RESUMO

A fatal case of common variable hypogammaglobulinaemia (CVH) is described. The patient presented with fulminant haemolytic anaemia. Post mortem examination revealed evidence of chronic hypogammaglobulinaemia.


Assuntos
Agamaglobulinemia/complicações , Anemia Hemolítica/etiologia , Adulto , Humanos , Masculino , Prognóstico
9.
Toxicol Appl Pharmacol ; 104(1): 117-29, 1990 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-2360202

RESUMO

Little is known about the mechanism of transport and distribution of volatile organic compounds in blood. Studies were conducted on five typical organic solvents to investigate how these compounds are transported and distributed in blood. Groups of four to five rats were exposed for 2 hr to 500 ppm of n-hexane, toluene, chloroform, methyl isobutyl ketone (MIBK), or diethyl ether vapor; 94, 66, 90, 51, or 49%, respectively, of these solvents in the blood were found in the red blood cells (RBCs). Very similar results were obtained in vitro when aqueous solutions of these solvents were added to rat blood. In vitro studies were also conducted on human blood with these solvents; 66, 43, 65, 49, or 46%, respectively, of the added solvent was taken up by the RBCs. These results indicate that RBCs from humans and rats exhibited substantial differences in affinity for the three more hydrophobic solvents studied. When solutions of these solvents were added to human plasma and RBC samples, large fractions (51-96%) of the solvents were recovered from ammonium sulfate-precipitated plasma proteins and hemoglobin. Smaller fractions were recovered from plasma water and red cell water. Less than 10% of each of the added solvents in RBC samples was found in the red cell membrane ghosts. These results indicate that RBCs play an important role in the uptake and transport of these solvents. Proteins, chiefly hemoglobin, are the major carriers of these compounds in blood. It can be inferred from the results of the present study that volatile lipophilic organic solvents are probably taken up by the hydrophobic sites of blood proteins.


Assuntos
Solventes/metabolismo , Administração por Inalação , Animais , Transporte Biológico , Eritrócitos/metabolismo , Éter/administração & dosagem , Éter/sangue , Éter/farmacocinética , Hexanos/administração & dosagem , Hexanos/sangue , Hexanos/farmacocinética , Humanos , Metil n-Butil Cetona/administração & dosagem , Metil n-Butil Cetona/sangue , Metil n-Butil Cetona/farmacocinética , Plasma/metabolismo , Ratos , Ratos Endogâmicos , Solventes/administração & dosagem , Solventes/farmacocinética , Tolueno/administração & dosagem , Tolueno/sangue , Tolueno/farmacocinética , Volatilização
12.
J Am Dent Assoc ; 117(5): 593-4, 1988 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-2976070

RESUMO

Derivatives of an antidiuretic hormone raise factor VIII levels in patients with mild or moderate hemophilia A. This case report describes the use of desmo-pressin acetate to raise the factor VIII level in a patient with hemophilia A, before and after extraction of 27 teeth.


Assuntos
Desamino Arginina Vasopressina/uso terapêutico , Assistência Odontológica para a Pessoa com Deficiência , Hemofilia A , Hemorragia Bucal/prevenção & controle , Extração Dentária , Adulto , Ácido Aminocaproico/uso terapêutico , Celulose Oxidada/uso terapêutico , Humanos , Masculino
13.
Scott Med J ; 32(5): 146-8, 1987 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-3441784

RESUMO

We present a case of testicular dermoid cyst in a 36 year old male. The relationship between this rare tumour and other differentiated teratomas is discussed.


Assuntos
Cisto Dermoide/patologia , Neoplasias Testiculares/patologia , Adulto , Humanos , Masculino
14.
J Infect ; 15(1): 45-56, 1987 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-2822811

RESUMO

For 32 years we have provided a routine histopathological service on animals for the Regional Virus Laboratory, Ruchill Hospital, Glasgow. This article concerns mainly experimental coxsackievirus A, coxsackievirus B and echovirus infections in new-born mice. In addition to previously reported findings, we have sometimes observed degenerative and inflammatory changes in neurons related to the Gasserian, posterior root or autonomic ganglia. Not all deposits of brown fat are simultaneously the seat of inflammatory changes; rarely, inflammation of brown fat spills over into the adjacent yellow adipose or connective tissues. Brown fat may occasionally show hyperplasia. Ballooning of the tips of small intestinal villi with interstitial oedema and/or necrosis of villous tips may indicate enanthemata associated with coxsackievirus A2,5,7,8,10,23 as well as with coxsackievirus B1 and B4 infections. Similar appearances were seldom seen with echovirus infections. Focal bone-marrow necrosis and necrosis of cartilage were associated with one coxsackievirus A10 infection, and osteitis with one coxsackievirus B3 infection. The implications of these uncommon observations for human pathology remain to be determined.


Assuntos
Infecções por Coxsackievirus/patologia , Infecções por Echovirus/patologia , Tecido Adiposo Marrom/patologia , Animais , Animais Recém-Nascidos , Echovirus 6 Humano , Echovirus 9 , Encefalite/patologia , Enterovirus , Enterovirus Humano B , Humanos , Camundongos , Miosite/patologia , Pancreatite/patologia
15.
Lancet ; 1(8541): 1089, 1987 May 09.
Artigo em Inglês | MEDLINE | ID: mdl-2883422
17.
Cancer ; 56(12): 2762-4, 1985 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-4052950

RESUMO

Doxorubicin has been reported to cause ventricular arrhythmias and sudden death in the first 24 hours after administration. The authors placed continuous electrocardiographic recording devices on 30 patients 24 hours before, during, and 24 hours after doxorubicin administration. Nine patients experienced arrhythmias before treatment; 12 patients had posttreatment ectopy. No patient had life-threatening arrhythmias before or after treatment. Of the nine patients with pretreatment ectopy, only one experienced an increase in severity. Conversely, six patients without ectopy before treatment had arrhythmias after doxorubicin administration. The authors were unable to determine predictive factors in patients with no pretreatment ectopy who developed posttreatment premature ventricular contractions. The authors conclude that antecedent ventricular ectopy exists in the oncologic population and that this is not worsened by first-dose exposure to doxorubicin.


Assuntos
Arritmias Cardíacas/induzido quimicamente , Doxorrubicina/efeitos adversos , Monitorização Fisiológica , Adulto , Idoso , Doxorrubicina/uso terapêutico , Eletrocardiografia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Neoplasias/tratamento farmacológico
18.
Gut ; 26(9): 935-44, 1985 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-3896961

RESUMO

The pathology of the alimentary tracts of nine patients dying of Salmonella typhimurium infection is reviewed. Two patients had previous gastric operations, supporting previous reports that such patients are more susceptible to food poisoning. Four had no parietal (oxyntic) cells in the gastric mucosa, suggesting hypo- or anacidity. Only one had acute gastritis. None had acute enteritis, but in half of the patients, subtle histological changes suggested an 'enteropathy'. Acute diffuse colitis with abundant crypt abscesses, without stromal abscesses in the lamina propria, was the most constant finding and reparative features started very early, and occurred in later deaths. Under ideal circumstances this crypt abscess is readily distinguished from that of idiopathic ulcerative colitis, but can be confused with the crypt abscess of acute bacillary (sonne) dysentery. While the florid colonic changes may have settled in the late deaths, active inflammation is commonly present in the appendix mucosa on histology. The pathology of the alimentary tract in S typhimurium infection differs from that of S typhi and S paratyphi infections. There is little evidence of gastroenteritis, although subtle changes occur in the stomach and small intestine. The features are those of acute diffuse colitis with histological appendicitis, distinguishable from idiopathic ulcerative colitis.


Assuntos
Intestinos/patologia , Intoxicação Alimentar por Salmonella/patologia , Estômago/patologia , Adulto , Idoso , Apêndice/patologia , Criança , Colo/patologia , Feminino , Humanos , Lactente , Mucosa Intestinal/patologia , Intestino Delgado/patologia , Masculino , Pessoa de Meia-Idade , Salmonella typhimurium
19.
Trans R Soc Trop Med Hyg ; 79(2): 192-202, 1985.
Artigo em Inglês | MEDLINE | ID: mdl-2988159

RESUMO

The histological and electron microscopic findings from a solitary cutaneous monkeypox lesion taken post mortem from a child who died after a five-day illness are reported. This child is 44th in the WHO register of monkeypox cases. The lesion was at the papulonecrotic stage, with early evidence of vesiculation and minimal evidence of pustulation. Necrosis affected the stratum basale, the related basement membrane and adjacent areas of the dermal papillae at the centre of the lesion. Cell necrosis affected the next two or three layers of stratum spinosum above the destroyed stratum basale. Lateral to this zone, marked hyperplasia and intracellular oedema of the stratum spinosum constituted the papule and produced spindle-cell features. In the middle layer of the stratum spinosum, above the necrotic focus, there were minute vesicles and between these were occasional multinuclear giant cells. Bodies similar to Guarnieri bodies (GB) were present in the cytoplasm of sweat duct-lining cells in the epidermis and upper corium. Very scanty similar bodies were evident elsewhere in the papular epidermis but were difficult to distinguish from debris. Granules in the lesion with the same size as mature virions (elementary bodies) have been assessed not to be these because similar granules are present in the normal epidermis. Changes in the dermis apart from those mentioned above were minimal oedema, very mild perivascular infiltration by round cells and an occasional eosinophil. Electron microscopy showed abundant immature and mature orthopoxvirus particles in the cytoplasms of infected epidermal cells. A limited range of histochemical tests is detailed. In general, the features are indistinguishable from the papulonecrotic stage of smallpox (variola) and from tanapox as recorded in man.


Assuntos
Infecções por Poxviridae/patologia , Pele/patologia , Pré-Escolar , Humanos , Corpos de Inclusão/ultraestrutura , Masculino , Microscopia Eletrônica , Monkeypox virus , Necrose , Pele/ultraestrutura
20.
J R Coll Gen Pract ; 34(264): 390-4, 1984 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-6747944

RESUMO

Irreparable damage to the anterior horn cells of the cervical and thoracic cord was found in a 20-week-old fetus whose mother was immune to poliomyelitis before conceiving but who was inadvertently given oral polio vaccine at 18 weeks gestation. Polio neutralizing antibody titres in sera, taken before and after pregnancy, were identical and were at levels normally regarded as providing protection. Unsuccessful attempts were made to isolate poliovirus from extracts of fetal brain, lung, liver and placenta. Fluorescent antibody tests were performed on various levels of the central nervous system and on the left and right extensor forearm muscles. Specific positive fluorescence to poliovirus 2 and 3 antigens was detected at dorsal spinal cord level only. One positive result was seen with Coxsackie A9 antiserum and fresh guinea-pig complement in the inflammatory cells in the right extensor forearm muscles.This experience, as yet unexplained, underlines the importance of ensuring that women are not pregnant prior to oral polio vaccination.


Assuntos
Doenças Fetais/etiologia , Poliomielite/etiologia , Vacina Antipólio Oral/efeitos adversos , Adulto , Células do Corno Anterior/patologia , Feminino , Doenças Fetais/patologia , Humanos , Poliomielite/patologia , Gravidez , Medula Espinal/patologia
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