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排序方式: 共有801条查询结果,搜索用时 31 毫秒
1.
This study investigates the association of wartime stress variables and coronary artery disease as determined by coronary angiography in Lebanon in 1986, a country with an ongoing civil war for over a decade. A total of 127 patients who underwent coronary angiography at the American University of Beirut Medical Center were individually matched on age and sex with visitor controls free from any evidence of clinical coronary artery disease. Arteriographic cases (greater than or equal to 70% maximal stenosis) were compared with two control groups: arteriographic controls (entirely normal coronaries) and visitor controls. Findings suggest that there is a relation between exposure to both acute and chronic war events and coronary artery disease in this patient population. The reporting of exposure to acute war events was significantly higher in cases compared with both visitor controls (odds ratio (OR) = 2.4, 95% confidence interval (Cl) 1.17-4.90) and arteriographic controls (OR = 2.8, 95% Cl 0.93-8.47). Crossing the "green-lines" that separate two belligerent sides, considered as an attribute of war-related chronic stress, was more frequent in cases compared with visitor controls (OR = 3.25, 95% Cl 1.54-6.89) and arteriographic controls (OR = 5.38, 95% Cl 1.65-17.6). The relation observed between wartime stress and coronary artery disease could not be explained by possible overreporting of stressful events in patients with suspected coronary artery disease or by an increase in clinical awareness for the disease for those under continuous stress. Adjusting for the effect of the well-established coronary artery disease risk factors did not alter the above findings.  相似文献   
2.
An 18- to 20-nm virus particle was isolated from the Olson strain of quail bronchitis, an avian adenovirus. On density gradient separation the small virions were primarily found at densities of 1.39 and 1.42 g/cm(3). The majority of the infectious particles were at the heavier density. The virus had a hexagonal outline and contained single-stranded deoxyribonucleic acid. It was resistant to heating at 56 C for more than an hour and was not inactivated by treatment with chloroform or low pH. Purified virus did not agglutinate erythrocytes of various avian and mammalian species. Replication of the small particles occurred either in chicken embryos or in cultures of embryo kidney cells coinfected with an adenovirus helper. Antigenically the virus was distinct from the adeno-associated viruses types 1, 2, 3, and 4. The virus is the avian equivalent of the adeno-associated viruses of primates and lower animals.  相似文献   
3.
J C Maroon  A Abla 《Neurosurgery》1985,16(5):644-649
A retrospective analysis of 50 consecutive patients treated with chemonucleolysis and 50 treated with microlumbar discectomy was carried out. Similar clinical criteria for the diagnosis of "virgin" herniated lumbar discs were used. All patients had low back or radicular pain unrelieved by a minimum of 4 weeks of conservative therapy. Physical findings included a positive straight leg raising sign, weakness of the appropriate muscle groups, and a sensory loss or evidence of depressed reflexes. All had myelograms or computed tomographic scans demonstrating an extradural defect. Compensation cases were eliminated. Results demonstrated a 90% marked improvement in the microdiscectomy category and a 58% marked improvement in the chemonucleolysis group. Four per cent of the microdiscectomy patients were unimproved, and 18% of the chemonucleolysis group required a subsequent surgical procedure. The average postoperative hospital stay was 3 days for both groups. Because of the necessity for reoperations in the chemonucleolysis group, chemonucleolysis seemed less cost-effective than microdiscectomy.  相似文献   
4.
We developed an assay that detects minus-strand RNA as a surrogate for actively replicating severe acute respiratory syndrome coronavirus 2. We detected minus-strand RNA in 41 persons with coronavirus disease up to 30 days after symptom onset. This assay might inform clinical decision-making about patient infectiousness.  相似文献   
5.
Many animal species exhibit approach-avoidance responses upon the novel placement of a mirror into an individual animal's environment. With a view toward identifying new behavioral measures with qualitatively or quantitatively different responses to anxiolytic agents, we developed a mirrored chamber apparatus for which adult male BALB/cByJ mice showed an extended latency to enter. Administration of diazepam significantly reduced this latency to enter a mirrored chamber in a dosage-dependent manner. The psychomotor stimulant, methylphenidate, had no effect on latency to enter the mirrored chamber at a dose which stimulated locomotor activity to the same extent as diazepam. Thus, the decreased latency to enter the mirrored chamber brought about by diazepam seems unlikely to reflect the motor effects of this benzodiazepine. The potency of diazepam was significantly lower in the mirrored chamber assay than it was on three other measures of exploratory activity--"head-dipping" performance, plus-maze performance and locomotor activity stimulation. The findings of our study indicate that the mirrored chamber method is simple to carry out, nonpunishing, rapid and quantitative and that it possesses pharmacological attributes which distinguish its response to anxiolytics from other assays of exploratory behavior.  相似文献   
6.
The purpose of this study was to investigate the correlation between low back pain persisting six months after first surgery for herniated lumbar intervertebral disc and the extent of peridural fibrosis present at the surgical site, as defined by magnetic resonance imaging (MRI). The 298 patients who underwent first-time, single-level unilateral discectomy for lumbar disc herniation were evaluated in a controlled, randomized, double-blind multicenter clinical trial to test the effectiveness of the scar-inhibiting device ADCON-L. Clinical assessments were conducted pre-operatively and at 1, 3, and 6-month intervals post-operatively, and included MRI scar assessment and the assessment of low back pain by visual analog scales. There were 267 patients available for low back pain assessments. The data obtained at the 6-month follow-up visit were statistically analyzed for the association between the presence of peridural scar and the persistence of low back pain. Those patients treated with ADCON-L at surgery had significantly less scar than did control patients (p = 0.007), and had less low back pain than did control patients when the pain was most severe (p = 0.047) and when the pain was assessed at the end of the day (p = 0.044). Patients with extensive scar reported continuing and debilitating low back pain more frequently than those with no or minimal scar. These findings demonstrate a direct correlation between persistent low back pain and extensive scar, since patients with increased amounts of scar had increased low back pain, regardless of their treatment group (p = 0.0003).  相似文献   
7.
This study investigates the association of wartime stress variables and coronary artery disease as determined by coronary angiography in Lebanon in 1986, a country with an ongoing civil war for ever a decade. A total of 127 patients who underwent coronary angiography at the American University of Beirut Medical Center were individually matched on age and sex with visitor controls free from any evidence of clinical coronary artery disease. Arteriographic cases (greater than or equal to 70% maximal stenosis) were compared with two control groups: arteriographic controls (entirely normal coronaries) and visitor controls. Findings suggest that there is a relation between exposure to both acute and chronic war events and coronary artery disease in this patient population. The reporting of exposure to acute war events was significantly higher in cases compared with both visitor controls (odds ratio (OR) = 2.4, 95% confidence interval (CI) 1.17-4.90) and arteriographic controls (OR = 2.8, 95% CI 0.93-8.47). Crossing the "green-lines" that separate two belligerent sides, considered as an attribute of war-related chronic stress, was more frequent in cases compared with visitor controls (OR = 3.25, 95% CI 1.54-6.89) and arteriographic controls (OR = 5.38, 95% CI 1.65-17.6). The relation observed between wartime stress and coronary artery disease could not be explained by possible overreporting of stressful events in patients with suspected coronary artery disease or by an increase in clinical awareness for the disease for those under continuous stress. Adjusting for the effect of the well-established coronary artery disease risk factors did not alter the above findings.  相似文献   
8.
Urethral duplication in the male: review of 16 cases   总被引:5,自引:0,他引:5  
PURPOSE: Urethral duplication is a rare congenital anomaly. The clinical presentation varies because of the different anatomical patterns of this abnormality. We describe our experience with 16 male patients with this anomaly. MATERIALS AND METHODS: We retrospectively reviewed the records of 16 male patients treated for urethral duplication in the last 10 years. Age at presentation ranged from newborn to 8 years. Evaluation included ultrasound, voiding cystourethrography, retrograde urethrography and endoscopy. RESULTS: A blind ending duplicated urethra (type I) was present in 4 patients, 2 independent urethras with distinct bladder necks (type IIA1) in 6, 2 urethras originating from a common bladder neck (type IIA2) in 4, and complete urethral and bladder duplication (type III) in 2. Six patients had associated vesicoureteral reflux. Duplication was an incidental finding at epispadias repair in 3 patients with bladder exstrophy, at hypospadias repair in 1 and at hydrocele repair in 1. One patient with bilateral dysplastic kidneys died in the newborn period. Surgical management included excision of the duplicated urethra in 8 cases and urethroplasty using a pedicle flap in 2, while surgical management was not required in 3. CONCLUSIONS: Urethral duplication is a rare congenital anomaly with a variable clinical presentation. This pathological condition may easily be under diagnosed, especially in patients with other associated anomalies, such as hypospadias or bladder exstrophy. Surgical management should be planned individually according to the anatomical findings of the abnormality.  相似文献   
9.
10.
Ochratoxin A (OTA) is a mycotoxin produced mainly by species of Aspergillus and Penicillium. Contamination of food with OTA is a major consumer health hazard. In Côte d’Ivoire, preventing OTA contamination has been the subject of extensive study. The current study was conducted to evaluate the influence of fermentation and drying materials on the OTA content in cocoa. For each test, 7000 intact cocoa pods were collected, split open to remove the beans, fermented using 1 of 3 different materials, sun-dried on 1 of 3 different platform types and stored for 30 days. A total of 22 samples were collected at each stage of post-harvesting operations. The OTA content in the extracted samples was then quantified by high-performance liquid chromatography. OTA was detected in beans at all stages of post-harvesting operations at varying levels: pod-opening (0.025 ± 0.02 mg/kg), fermentation (0.275 ± 0.2 mg/kg), drying (0.569 ± 0.015 mg/kg), and storage (0.558 ± 0.04 mg/kg). No significant relationships between the detected OTA level and the materials used in the fermentation and drying of cocoa were observed.  相似文献   
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