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991.
PURPOSE: To investigate the frequency of amblyopia among visually handicapped patients. METHODS: The study is a retrospective investigation of all living patients registered in four Visual Rehabilitation Centres in a region in southern Sweden. The area's total population numbered 865,612 persons of whom 11,365 were registered as visually handicapped (with visual acuity < or = 0.3 in the better eye). RESULTS: Amblyopia was the main cause of decreased visual acuity in one eye in 1.72% (195 of 11,365) of the patients. The average age of the patients with amblyopia was 69 years (9-95 years) and 28.2% of these patients were less than 65 years old (the age for retirement in Sweden). The median visual acuity in the amblyopic eye among these patients was 0.1. The median visual acuity in the nonamblyopic eye was 0.2. The most common cause of decreased vision in the nonamblyopic eye was macular degeneration (39.5%). Bilateral amblyopia was present in 13 (6.7%) of the amblyopic patients. By comparing this study with earlier studies, we can calculate that about 1.2% of the persons with amblyopia 0.3 or lower will eventually become visually handicapped. CONCLUSION: A small but considerable number of patients who attend the Visual Rehabilitation Centres have amblyopia as a cause of their visual impairment. Since amblyopia can be treated if detected in childhood, later visual rehabilitation of these patients can be avoided or delayed, thereby reducing rehabilitation costs for society.  相似文献   
992.
993.
Yin H  Berg AK  Tuvemo T  Frisk G 《Diabetes》2002,51(6):1964-1971
We have studied the occurrence of enterovirus (EV)-RNA at the onset of childhood type 1 diabetes in all 24 new cases of childhood type 1 diabetes during 1 year in Uppsala county, Sweden. We also studied 24 matched control subjects and 20 siblings of the patients. RNA was isolated from peripheral blood mononuclear cells and EV-RNA detected by RT-PCR. Primers (groups A and B) corresponding to conserved regions in the 5' noncoding region (NCR) of EV were used in the PCRs, and the amplicons were sequenced. By the use of group A primers, EV-RNA was found in 12 (50%) of the 24 type 1 diabetic children, 5 (26%) of 19 siblings, and none of the control subjects. Both patients and siblings showed a higher frequency of EV-RNA compared with the control subjects. The group B primers detected EV-RNA in all three groups but did not show statistically significant differences between the groups. The EV-RNA positivity with the group B primers was 11 (46%) of 24 in the type 1 diabetic children, 11 (58%) of 19 in the siblings, and 7 (29%) of 24 in the control subjects. The significant difference between groups seen with the group A primers but not with the group B primers might indicate the existence of diabetogenic EV strains. The phylogenetic analysis of the PCR products revealed clustering of the sequences from patients and siblings into five major branches when the group A PCR primers were used. With the group B primers, the sequences from patients, siblings, and control subjects formed three major branches in the phylogenetic tree, where 6 of the 7 control subjects clustered together in a sub-branch of CBV-4/VD2921. Seven of the type 1 diabetic children clustered together in another sub-branch of CBV-4/VD2921. Five of the type 1 diabetic children formed a branch together with the CBV-4/E2 strain, four clustered together with CBV-5, and one formed a branch with echovirus serotype. The presence of EV-RNA in the blood cells of most newly diagnosed type 1 diabetic children supports the hypothesis that a viral infection acts as an exogenous factor. In addition, sequencing of the PCR amplicons from the type 1 diabetic children, their siblings, and matched control subjects might reveal differences related to diabetogenic properties of such a virus.  相似文献   
994.
Summary. Summary.   Patients and Interventions: Tissue damage caused by brain retraction was evaluated utilizing intracerebral microdialysis in six patients operated on subfrontally for pituitary adenoma. The microdialysis probes (membrane length 10 mm, cut-off 20 kDalton) were placed in cerebral cortex beneath the brain retractor and perfused with Ringer solution at 0.3 μl/min. The microdialysis vials were changed at intervals of 30 minutes and analysed for glucose, pyruvate, lactate, glutamate and glycerol.   Results: During brain retraction regional intracerebral glucose was within normal range in cortical tissue and the levels of lactate, glutamate, and glycerol as well as the lactate/pyruvate ratio were considerably above normal range.   Conclusion: The biochemical analysis shows a pronounced incomplete cerebral ischemia due to brain retraction. The increases in glutamate and glycerol indicate tissue damage and degradation of cell membranes. Intracerebral microdialysis may be a valuable tool in the development of optimal techniques for brain retraction during neurosurgical procedures. Published online July 18, 2002 ? Springer-Verlag 2002  相似文献   
995.
Lactate measurements in scalp and cord arterial blood   总被引:5,自引:0,他引:5  
Lactate has been measured to evaluate fetal metabolic acidosis for some decades. However, not until the past few years have reliable lactate meters become available for bedside obstetric practice. The new technology, which requires only 5 microl blood, has reduced the sampling failure rate of fetal scalp blood to almost nil. A growing body of evidence has also shown lactate to be good at predicting neonatal outcome.  相似文献   
996.
997.
Aims: To update the analysis of the cohort mortality and cancer incidence study of employees in the Australian petroleum industry.

Methods: Employees from 1981 to 1996 were traced through the Australian National Death Index and the National Cancer Statistics Clearing House. Cause specific mortality and cancer incidence were compared with those of the Australian population by means of standardised mortality ratios (SMRs) and standardised incidence ratios (SIRs). Associations between increased incidence of specific cancers and employment in the petroleum industry were tested by trends according to period of first employment, duration of employment, latency, and hydrocarbon exposure, adjusting for personal smoking history where appropriate. Total follow up time was 176 598 person-years for males and 10 253 person-years for females.

Results: A total of 692 of the 15 957 male subjects, and 16 of the 1206 female subjects had died by the cut off date, 31 December 1996. In males, the all-cause SMR and the SMRs for all major disease categories were significantly below unity. There was a non-significant increase of the all-cancer SIR (1.04, 95% CI 0.97 to 1.11). There was a significant increase of the incidence of melanoma (SIR 1.54, 95% CI 1.30 to 1.81), bladder cancer (SIR 1.37, 95% CI 1.00 to 1.83), and prostate cancer (SIR 1.19, 95% CI 1.00 to 1.40), and a marginally significant excess of pleural mesothelioma (SIR 1.80, 95% CI 0.90 to 3.22), leukaemia (SIR 1.39, 95%CI 0.91 to 2.02), and multiple myeloma (SIR 1.72, 95% CI 0.96 to 2.84).

Conclusions: Most cases of mesothelioma are probably related to past exposure to asbestos in refineries. The melanoma excess may be the result of early diagnosis. The excess bladder cancer has not been observed previously in this industry and is not readily explained. The divergence between cancer incidence and cancer mortality suggests that the "healthy worker effect" may be related to early reporting of curable cancers, leading to increased likelihood of cure and prolonged mean survival time.

  相似文献   
998.
BACKGROUND: Patients with long-standing extensive ulcerative colitis (UC) have an increased risk of developing colorectal cancer (CRC). High-risk UC patients are nowadays enrolled in surveillance programs to decrease CRC incidence and mortality, although little is known about patients' concerns and anxiety when subjected to colonoscopic surveillance. The aims of this study were to evaluate functional health status, general state of health, anxiety, and coping ability in patients with UC taking part in such a program in a university hospital setting. METHODS: Forty-one patients with long-standing, extensive/total UC in remission (median disease duration, 21.0 years) undergoing surveillance comprised the study group. Twenty patients with extensive disease but with shorter disease duration (median, 8.0 years) and 19 patients with only distal involvement UC acted as controls. Four different self-administered questionnaires (SAQs) were used. The SAQ assessments were made twice in the study group and once in the controls. RESULTS: No statistically significant differences were found in any of the SAQ assessments. The median scores obtained were well within the ranges seen in normal healthy subjects. CONCLUSIONS: Colonoscopic surveillance in long-standing UC does not seem to generate increased anxiety or impairment of functional or general health status among participating patients. Rather, UC patients in clinical remission seem to cope just as well as healthy individuals irrespective of the CRC risk or surveillance procedures.  相似文献   
999.
Major therapeutic advances in the rehabilitation of subacute stroke are lacking. One promising approach is treatment with amphetamine in combination with physiotherapy so as to promote motor function. In a randomized, double-blind, placebo-controlled clinical trial, the effect of 10 sessions with 10 mg of amphetamine combined with physiotherapy during a 5-week period was investigated in 39 geriatric patients who had been admitted to a stroke rehabilitation unit. Motor function (Fugl-Meyer motor performance score) and activities of daily living (ADL; Barthel's index) were assessed at baseline and at the end of treatment. All patients improved significantly over the intervention period. Amphetamine-treated patients did not show any increase in motor function or ADL as compared to the control group. Rehabilitation with amphetamine at this dosage and interval, combined with physiotherapy, did not promote motor recovery or functional capacity in patients suffering from stroke.  相似文献   
1000.
BACKGROUND: Microdialysis with bedside biochemical analysis was used to monitor cerebral biochemical alterations that precede and accompany increase in intracranial pressure (ICP), resulting in a complete cessation of cerebral blood flow. METHODS: Seven patients, who died due to an untreatable increase in ICP, were included. The patients originate from a large, consecutive series of severely head injured patients (n: 95) monitored with intracerebral microdialysis (perfusion rate 0.3 microl/min). One microdialysis catheter was inserted via a separate burr hole frontally to that used for the intraventricular catheter ("better" position) and one catheter was inserted into cerebral cortex surrounding an evacuated focal contusion or underlying an evacuated haematoma ("worse" position). Biochemical analyses of glucose, lactate, glycerol, urea, glutamate, and pyruvate were performed at the bedside. All samples were frozen for subsequent HPLC (high-performance liquid chromatography) analyses of amino acids and ions. RESULTS: Decreases in glucose and pyruvate and increases in lactate, glycerol, glutamate, and lactate/pyruvate (la/py) ratio characterized cerebral ischaemia. The measured markers give information regarding substrate availability (glucose), redox state of the tissue (la/py ratio), degradation of glycerophospholipids in cell membranes (glycerol), and extracellular concentration of excitatory amino acids (glutamate). In the "worse" position biochemical deterioration occurred before the increase in ICP. In the "better" position biochemical deterioration was usually observed after the increase in ICP. CONCLUSION: Changes of cerebral energy metabolism that accompany cerebral ischaemia follow a certain pattern and may be detected at the bedside by intracerebral microdialysis before the secondary damage causes an increase in ICP.  相似文献   
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