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排序方式: 共有7159条查询结果,搜索用时 15 毫秒
991.
DR Offord MH Boyle D Campbell P Goering E Lin M Wong YA Racine 《Canadian Metallurgical Quarterly》1996,41(9):559-563
OBJECTIVE: To present the one-year prevalence of 14 psychiatric disorders in a community sample of Ontarians aged 15 to 64 years. METHOD: Data on psychiatric disorders were collected on 9953 respondents using the University of Michigan revision of the Composite International Diagnostic Interview (UM-CIDI). DSM-III-R criteria were used to define the psychiatric disorders. RESULTS: Almost 1 in 5 Ontarians (18.6%) had one or more of the disorders measured in the survey. Among 15-to 24-year-olds, 1 in 4 was affected. The distribution of individual disorders varied by sex and age. CONCLUSION: Because of the immense burden of suffering associated with psychiatric disorders, clinical and research efforts in this area should receive high priority within the health budget. 相似文献
992.
Doppler grid surface scanning applications for pulmonary subsurface parenchymal perfusion assessment
M Brenner TE Milner NS Wang JC Chen R McKenna LT Norvang TA Waite A Hamilton H Wong AF Wilson Y Tadir MW Berns 《Canadian Metallurgical Quarterly》1996,14(6):367-374
Subsurface perfusion to lung parenchyma underlying the pleura is difficult to assess in live ventilated animals. The purpose of this study was to assess applicability of a newly developed laser Doppler grid scanning imaging technology that measures perfusion of pleural subsurface lung regions in intact normal and abnormal animal lungs. Eighty-six Doppler grid perfusion measurements were performed in five New Zealand White Rabbits (3-5 kg); four with unilateral bullous lung disease, one normal control. Left upper lobe lung surface was exposed to 10 1-sec spot Nd:YAG exposures (70 W/cm2). One week following laser exposure, all rabbits underwent sequential bilateral open thoracotomy. Unaffected left lower lobes in these animals and all four lobes of a previously untreated rabbit were used as controls. Pleural subsurface perfusion measurements were recorded over a contiguous 900-pixel square surface grid using quantitative noncontact laser Doppler imaging during open thoracotomy procedures. Scans were obtained in a normal volume ventilation mode, at 30 cm of inspiratory hold airway pressure, and postinflation. A perfusion-pressure response curve was obtained in normal lung at 10-, 20-, and 30-cm static airway pressure. Post mortem measurements were used as 0 flow controls. Normal lung tissue was found to have relatively high pleural subsurface perfusion (1362 +/- 328 corrected units on a scale of 0-4095). Areas of atelectasis had decreased perfusion (659 +/- 512 U., 48.4 +/- 12.5% compared to normal lung, p < 0.02), but returned to normal levels after inflation of the lung (1253 +/- 363 U., p = 0.21 compared to normal). Pleural subsurface perfusion decreased uniformly and progressively as lung inflation pressure increased (p < 0.0001). Perfusion increased immediately to supranormal values following release of high inspiratory inflation pressure holds (1603 +/- 626 U., 117 +/- 18% compared to normal lung, p = 0.03). Bullae had markedly decreased perfusion (541 +/- 68 U.) that was not further reduced by increased inflation pressures. Noncontact laser Doppler grid perfusion imaging appears to provide a new tool for measuring pleural subsurface perfusion over a large area of lung surface in clinical experimental settings. Results are rapid, reproducible, and consistent. Sampling errors inherent in current point sampling Doppler flow techniques are reduced by the multiple contiguous measurements. We have used this technique to demonstrate inspiratory pressure-related reduction in pleural subsurface perfusion in normal lung, reversible decreased perfusion in atelectatic regions, and reduced perfusion in bullous and laser-treated lung regions. 相似文献
993.
Idiopathic adhesive capsulitis usually responds to gentle physical therapy or, if that fails, to closed manipulation with the patient under anesthesia. In some patients, however, loss of motion may be refractory to either of these treatments and an operative release may be indicated. We are reporting on the technique and results of arthroscopic capsular release as a new alternative for the management of such patients. During a three-year period, we managed twenty-three patients who had idiopathic adhesive capsulitis that had failed to respond to physical therapy or closed manipulation. These patients had an arthroscopic anterior capsular release and received forty-eight hours of intensive physical therapy as inpatients. During the physical therapy, the patients received an interscalene regional analgesic with use of repeated nerve blocks or with a continuous infusion through an interscalene catheter. This was followed by a supervised outpatient physical-therapy program. Six patients also had an arthroscopic acromioplasty for the treatment of impingement. There were no complications related to any of the procedures. At a mean of thirty-nine months (range, twenty-four to sixty-four months) after the arthroscopic procedure, the improvement in the score of Constant and Murley averaged 48 points (range, 13 to 77 points). The mean improvement in motion was 49 degrees (range, 0 to 105 degrees) for flexion; 42 degrees (range, 10 to 80 degrees) and 53 degrees (range, 0 to 100 degrees) for external rotation in adduction and abduction, respectively; and eight spinous-process levels (range, three to fourteen levels) and 33 degrees (range, 30 to 60 degrees) for internal rotation in adduction and abduction, respectively. These gains in motion were all significant (p < 0.01) compared with the preoperative values and were within a mean of 7 degrees of the values for the contralateral, normal shoulder. We concluded that, in patients who have loss of motion that is refractory to closed manipulation, arthroscopic capsular release improves motion reliably with little operative morbidity. 相似文献
994.
995.
The phenotypic characteristics of three Serpulina pilosicoli strains isolated from humans with diarrhoea (WesB, Kar, Hrm7) and two porcine S. pilosicoli strains isolated from pigs with intestinal spirochaetosis (1648, 3295), were compared with the type strain of the species P43/6/78T (T = type strain) and other intestinal spirochaetes within the genus Serpulina. All S. pilosicoli strains had a characteristic ultrastructural appearance, displayed similar growth rates, hydrolysed hippurate, lacked beta-glucosidase activity, utilised D-ribose as a growth substrate, and had similar sensitivities to rifampicin and spiramycin. The only consistent phenotypic characteristic that differentiated human strains from porcine strains of S. pilosicoli was that the human strains all utilised the pentose sugar D-xylose. These distinguishing phenotypic traits appear useful for identifying S. pilosicoli. 相似文献
996.
997.
Three sporulation-specific genes (orfA, sigE, sigG) from clostridium acetobutylicum ATCC 824 are arranged in a cluster, encoding the putative sigma E-processing enzyme, sigma E, and sigma sigma G respectively. When they were transformed into Clostridium acetobutylicum while on a plasmid functional in this organism, transformants did not survive. Three kinds of recombinations were then attempted with nonreplicative plasmids: duplication of orfA and sigE, replacement of all of the three genes, and inactivation of orfA. While the wild-type strain ceased to grow and produce solvents in batch cultures after approximately 24 h, mutant strains were isolated that showed sustained growth for a much longer time and produced a threefold increase in acetone and butanol in test tube cultures. In addition, one of the derived strains showed a significantly higher growth rate. Features of the restriction maps of the recombinants did not correlate with expected maps, indicating possible complications occurring during the recombination events. 相似文献
998.
M Brenner T Shankel NS Wang TA Waite H Wong A Hamilton Y Tadir T Milner J Boyajian E Chung B Tromberg AF Wilson MW Berns 《Canadian Metallurgical Quarterly》1996,153(3):1136-1140
Laser exposure of the pulmonary parenchyma during treatment of emphysema and other clinical indications causes acute lung injury. Animal investigations are needed to understand and control laser-induced lung injury. We hypothesized that lung injury is deeper from Nd:YAG laser exposures than CO2 exposures because of deeper penetration of Nd:YAG wavelength light. We compared the temporal evolution of histologic injury in rabbits resulting from continuous mode shallow CO2 and Nd:YAG laser pulmonary parenchymal exposures applied in rabbits. Forty-six New Zealand white (NZW) rabbits underwent treatment with CO2 laser (n=18), Nd:YAG laser (n=18), or sham thoracotomy control (n=10) to the visceral pleural surface using 1 min of exposure (5 watts, defocused to 70 W/cm2 power density for both lasers). Animals were killed at 0, 4, 7, 21, and 49 d after exposure. Lung injury, similar to that seen clinically in humans, developed in all laser-treated animals. Injury progressed from ischemia and vascular congestion, to edema and necrosis, followed by pleural and parenchymal fibrosis. The acute injury was qualitatively distinct and slightly deeper in CO2 than Nd:YAG-treated animals (p<0.02) despite the shallower depth of penetration of the CO2 laser. These findings may imply that higher absorption coefficient for CO2 laser energy results in greater focal temperatures and injury in the areas of direct exposure, and suggest that Nd:YAG laser exposure at these settings may cause shallower injury than CO2 lasers in humans undergoing clinical treatment. 相似文献
999.
When bone is fractured, a sequence of dynamic events ensue to restore form and therefore function. Many key biologic cell regulators for these events have been identified, expressed through recombinant technology, and their roles posited. Moreover, the availability of recombinantly engineered molecules, such as the bone morphogenetic proteins with their potential to benefit patient care, has ushered in an important era in clinical dentistry that may eliminate either autografting or bank bone allografts. Therefore, in this review article, we have highlighted some of the exciting biologic regulators relevant to bone fracture healing and outlined the dynamic elements in this process. 相似文献
1000.
AA Binhazim TA Rizvi LG Coghlan K Lew R Schmidt PK Wong 《Canadian Metallurgical Quarterly》1996,75(3):339-348
By serving as host recipients of xenografts from both humans and animals, severe combined immunodeficient (SCID) mice have become valuable to many laboratories interested in examining the pathophysiology of different diseases. To gain insight into the usefulness of the SCID mutation in retrovirus research, rhesus monkey fetal hematolymphoid tissues (liver and thymus) were used to construct a SCID-rhesus chimeric mouse (SCID-rh) and were engrafted in the renal capsule. The size and maturation of the thymic engrafts were monitored grossly, histologically, and immunologically. SCID mice were tolerant to rhesus tissues, and thymic engrafts contained thymocytes at different stages of maturation and differentiation that had morphologic features similar to age-matched rhesus thymus. Mature single positive CD2+, CD4+, and CD8+ T lymphocytes that were phenotypically similar to rhesus T lymphocytes were present at low levels (2% to 5%) in the peripheral blood and at moderately higher levels (7% to 15%) in the spleens of SCID-rh mice obtained between 12 and 15 weeks after thymus/liver engraftment. Within 3 weeks after engraftment, > 85% of the thymocytes in the thymic engrafts were immature double positive CD4+CD8+ T cells. The highest number of positive cells were seen in thymic engrafts obtained at 12 to 18 weeks. During these weeks, > 90% of the cells were double positive (CD2+CD4+, CD2+CD8+, and CD4+CD8+). After infection of the engrafted thymus tissue with simian immonodeficiency virus (SIVmac239), PCR analysis revealed successful viral infection of engrafts at 2 and 4 weeks after infection. No significant histopathologic and flow cytometric changes were observed in the thymic engrafts at 2 and 4 weeks after infection. An unrelated lesion of thymic lymphomas involving the SCID host thymus was seen in 12% of the mice. The data presented herein suggest that the SCID-rh is a valuable model for specific studies related to thymus-retrovirus interaction and that it could be used for further studies. The results are discussed in relation to current knowledge of thymus involvement during simian and human immunodeficiency virus infection. 相似文献