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排序方式: 共有371条查询结果,搜索用时 500 毫秒
71.
72.
Clinical evaluation of total serum calcium in primary hyperparathyroidism and the risk of death after surgery 总被引:2,自引:0,他引:2
Abstract. This study aims to understand the behaviour and clinical value of total serum calcium in untreated primary hyperparathyroidism, to identify the significant relationship between pre-operative total serum calcium and the risk of death after surgery, and to consider the issue of when to operate. The risk of death after surgery was studied as dependent on pre-operative serum calcium levels in a series of 896 patients followed up for mean 12.9 years (SD 6.1) after surgery. The predictive power of pre-operative peak calcium levels was stronger than that of mean calcium levels. It was found that an increase of peak serum calcium from 2.60 mmolL-1 to 2.90 in one patient meant a death risk increase, with 38% still 5 years after surgery. The marginal risk increase per mmolL-1 was found to be higher below the peak serum calcium level of 2.90 mmolL-1 than above that level. The variation of total serum calcium before surgery was found to be substantial and the occurrence of transient high serum calcium levels was not unusual. Therefore, conservative surveillance with yearly total serum calcium estimations seems insufficient. Rather, early surgery, when serum calcium levels are not more than moderately increased, appears to be the most favourable alternative. 相似文献
73.
E. BJÖRNSSON D. NORBÄCK C. JANSON J. WIDSTRÖM U. PALMGREN† G. STRÖM† G. BOMAN 《Clinical and experimental allergy》1995,25(5):423-431
As a part of a worldwide investigation on the prevalence of respiratory symptoms, we have performed a study on the relationship between the indoor environment and asthma-like symptoms in the population of a central Swedish municipality. The study comprised 88 individuals, aged 20–45 years who underwent a structured interview, spirometry, a methacholine provocation test, skin-prick tests and blood samples for measurements of serum concentrations of eosinophil cationic protein (S-ECP), blood eosinophil count and total immunoglobulin E (S-IgE). In the homes, the room temperature, air humidity, respirable dust, house dust mites (HDM) and airborne micro-organisms were measured. The relative humidity in all the homes was found to be above 33%. HDM were found in 13% of homes. In the homes of the 47 subjects with asthma related symptoms, significantly higher total levels of bacteria and mould (P<0.05) and a higher proportion of detected HDM (OR = 5.3) was found than in subjects with no asthma related symptoms, after adjustment for age, sex, smoking, indoor temperature and air humidity. HDM were found to be an independent risk factor for asthma related symptoms (OR = 7.9) and nocturnal breathlessness (OR = 6.2) (P<0.05), while the total level of bacteria was a risk factor for asthma related symptoms and wheezing (P<0.05). We conclude that although HDM is relatively infrequently found in the homes of central-Sweden, the presence of HDM is related to asthmatic symptoms. A relation between levels of airborne bacteria and asthma related symptoms was also found. 相似文献
74.
PC Ng TF Fok CH Lee KL Cheung CK Li KW So W Wong PMP Yuen 《Acta paediatrica (Oslo, Norway : 1992)》1998,87(11):1197-1199
Two cases of homozygous α-thalassaemia who received active treatment in accordance with parental wishes are reported. One infant survived and the other, although successfully weaned off mechanical respiratory support, unexpectedly developed portal vein thrombosis and died. Homozygous a-thalassaemia, a condition previously considered to be universally fatal, and an indication for therapeutic abortion, is now potentially curable with advances in diagnostic technology and treatment. However, active management of these cases raises serious ethical questions and has major financial implications on the health-care system. Invasive prenatal and intensive postnatal interventions should remain experimental and cannot be recommended as routine clinical practice until the questions of long-term neurodevelopmental outcome, and the morbidity and mortality associated with bone-marrow transplantation have been fully addressed. As a result of advances in information technology, more and more parents of affected foetuses are likely to request active treatment. 相似文献
75.
ABSTRACT. The prevalence of asthma among 10527 children aged 7–16 years was investigated in 1985. Children were assigned to the asthma group when replies to a questionnaire stated that at least two of four stipulated symptoms had been experienced in the preceding year. A validation study, comprising exploration of medical history, pulmonary auscultation and physiological tests (spirometry and methacholine inhalation challenge) was performed in 73 children. The overall prevalence of asthma was 4%. The most common symptom-inducing factors were physical exertion, upper respiratory tract infection, contact with animals and tobacco smoke. The methacholine test had limited value as a diagnostic aid, being positive in only 25% of children with a clear history of asthma. 相似文献
76.
The in-vivo effects of systemic administration of recombinant human interleukin 1 beta (rIL-1 beta) were studied in the mouse contact-sensitivity model. rIL-1 beta in a single dose of 20 micrograms injected intraperitoneally 72-48 h before or 2-24 h after sensitization suppressed contact sensitivity. Given before challenge rIL-1 beta modulated the response in a biphasic way with an enhancement at 48 h and a suppression at 2 h before challenge. Only microgram doses of rIL-1 beta could enhance the contact sensitivity at 48 h, while microgram doses of rIL-1 beta at 2 h before challenge suppressed and nanogram doses enhanced the response. Treatment with indomethacin could only abrogate the effects of nanogram doses of rIL-1 beta. Measurements of the thickness of unchallenged control ears revealed that rIL-1 beta by itself could cause a small but significant increase in thickness depending on the dose and the time of administration. 相似文献
77.
78.
Anterior temporal lobes and hippocampal formations: normative volumetric measurements from MR images in young adults 总被引:25,自引:0,他引:25
Jack CR Jr; Twomey CK; Zinsmeister AR; Sharbrough FW; Petersen RC; Cascino GD 《Radiology》1989,172(2):549-554
Volumes of the right and left anterior temporal lobes and hippocampal formations were measured from magnetic resonance images in 52 healthy volunteers, aged 20-40 years. Subjects were selected by age, sex, and handedness to evaluate possible effect of these variables. Data were normalized for variation in total intracranial volume between individuals. Right-left asymmetry in the volumes of the anterior temporal lobes and hippocampal formations was a normal finding. The anterior temporal lobe of the non-dominant (right) hemisphere was larger than the left by a small (mean right-left difference, 2.3 cm3) but statistically significant amount (P less than .005) in right-handed subjects. No significant effect of age or sex was seen in normalized right or left anterior temporal lobe volume. The right hippocampal formation was larger than the left for all subjects by a small (mean right-left difference, 0.3 cm3) but statistically significant amount (P less than .001). No effect of age, sex, or handedness was seen in normalized hippocampal formation volumes. 相似文献
79.
M. I. BOKAREWA G. FALK K. BREMME M. BLOMBÄCK & B. WIMAN 《European journal of clinical investigation》1997,27(4):340-345
A total of 74 non-pregnant women with a previous episode of thrombosis were investigated for activated protein C (APC) resistance in the aPTT-based and factor IXa-X-based assays and for the presence of mutations in all APC-cleavage sites in the heavy chains of factor V and factor VIII. DNA fragments were amplified with the polymerase chain reaction (PCR) and those encoding for the Arg-306 and Arg-506 (factor V) and for Arg-740 (factor VIII) cleavage sites were subjected to restriction enzyme analysis. DNA fragments of 29 selected patients corresponding to the Arg-306 and Arg-679 cleavage sites in factor V, and to the Arg-336 and Arg-562 cleavage sites in factor VIII were sequenced. APC resistance was found in 40 cases, using the aPTT-based assay and in 35, using the factor IXa-X-based assay (23 patients were APC resistant in both assays), whereas 22 individuals had a normal response to APC. Forty-three patients carried Arg-506 to Gln mutation in factor V. No other polymorphism or mutation was found in the genes for factors V or VIII in the vicinity of the APC cleavage sites. It was concluded that the difference in response to APC in the two assays may not be explained by the presence of mutations in the APC cleavage sites of factor V and factor VIII in this group of patients. The data do not exclude the presence of mutations elsewhere in the factor V or factor VIII genes. 相似文献
80.
Three previously healthy infants presented with diarrhoea and pyrexia and deteriorated rapidly. Two patients had necrotizing bowel disease requiring aggressive surgical intervention. All survived. P. aeruginosa gastrointestinal infection in previously healthy children is an extremely rare condition with a high mortality. Ecthyma gangrenosum was present in over 60% of reported cases although often not recognized initially. A high index of clinical suspicion, including prompt recognition of ecthyma gangrenosum, is mandatory for an early diagnosis of P. aeruginosa gastrointestinal infection. Early diagnosis and treatment may improve the prognosis. 相似文献