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1.
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   
2.
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   
3.
Bulletin of Environmental Contamination and Toxicology - The application of Cu and CuO nanofertilizers in horticulture has been a promising strategy to promote plants’ growth. In our study,...  相似文献   
4.
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   
5.
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   
6.
Calculi from 45 Moroccan children aged between 2 and 15 years underwent morphological and infrared spectrometric analysis. The stones were three times more frequent in males than females (M/F = 3.09). Whewellite was the main component in 51.1% of cases and in 44.4% of stone nuclei, wheddellite in 8.9% of stones and nuclei, carbapatite in 6.7% of stones and 8.9% of nuclei, struvite in 15.6% of stones and 11.1% of nuclei. Ammonium hydrogen urate and uric acid were predominant respectively in 8.9% and 6.7% of stones and in 15.6% and 11.1% of nuclei. In addition to whewellite, struvite and ammonium hydrogen urate were the main components of bladder stones from both sexes. With respect to their calculi, whewellite was present in 84.4% of cases and wheddellite in 26.7%. Purines were present in 46% of calculi, especially as ammonium urate (28.9%) and uric acid (15.6%). Calcium phosphates as the main components were infrequent. In contrast, they were frequently identified in urinary calculi from children, respectively 64.4% and 40% for carbapatite and amorphous carbonated calcium phosphate.  相似文献   
7.
Two inbred mouse strains, SWR and CBA, differed significantly in their susceptibility to acute dose dependent theophylline- and caffeine-induced stimulation of locomotor activity. The efficacy of both methylxanthines was reduced in the SWR strain compared to the CBA strain. When brain levels of theophylline were determined at a dose (32 mg/kg IP) which gave maximal behavioral separation of the two strains, no significant differences were found between them (SWR levels 12.5 +/- 1.9, CBA levels 14.3 +/- 1.7 micrograms/g wet weight brain). The dose dependent ability of several adenosine agonists (N6-cyclohexyladenosine, (-)-N6-phenylisopropyladenosine, 5'-N-ethylcarboxamidoadenosine) to depress locomotor activity was investigated. SWR mice were found to be significantly more sensitive to NECA-induced depression of locomotor activity and the NECA-induced hypothermia than were CBA mice (respective ED50 values for inhibition of activity, 11.6 and 30.5 nmoles/kg IP). No differences were found in brain [3H]-NECA levels at doses which produced marked differences in behavioral effects between the two strains. The differences in adenosine agonist sensitivity between the strains were both agonist- and behavior-specific. These data indicate that an inherited alteration in behavioral responsiveness to methylxanthine administration can be inversely associated with inherent alterations in susceptibility to the action of specific adenosine analogs. An adenosine A-2 receptor sub-class may be involved in these changes in in vivo pharmacological susceptibility to the action of both methylxanthines and adenosine agonists on locomotor activity.  相似文献   
8.
9.
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   
10.
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