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1.
2.
Allograft anterior cruciate ligament reconstruction in a sheep model. The effect of synthetic augmentation. 总被引:2,自引:0,他引:2
The purpose of this study was to assess the effect of synthetic augmentation of a bone-patellar tendon-bone allograft on the basis of biomechanical, morphologic, and histologic evaluation. The anterior cruciate ligament was reconstructed in the left knee of 66 adult sheep. Half the knees received bone-patellar tendon-bone grafts alone, while the other half were augmented. All of the knees, including the contralateral controls, had gross and histologic examination, hydroxyproline assay for collagen content, and biomechanical testing in groups at 0, 4, 16, and 52 weeks postoperatively. Biomechanical testing included anteroposterior translation, ultimate tensile strength, energy to failure, stiffness, and mode of failure. Eight fresh bone-patellar tendon-bone allografts were compared to eight cryopreserved bone-patellar tendon-bone allografts for baseline data on the effects of the cryopreservation. Cryopreservation did not have any effect on graft characteristics. Gross and histologic examination did not reveal any significant difference between the augmented and nonaugmented groups at any of the time periods. In addition, hydroxyproline content of the allograft was not altered by augmentation throughout the study period. Biomechanical laboratory evaluation demonstrated the augmented group had significantly reduced anteroposterior translation (P less than 0.05) at 52 weeks compared to the nonaugmented group. The ultimate tensile strength was significantly higher (P less than 0.05) in the augmented group at 4 weeks, but at 52 weeks both groups had attained only 50% of the normal anterior cruciate ligament strength. Stiffness and energy to failure were similar in both groups at all time periods. From the results of this study, synthetic augmentation appears to improve initial strength and prevent late allograft laxity while allowing normal remodeling processes to occur in the bone-patellar tendon-bone allograft anterior cruciate ligament reconstruction. 相似文献
3.
Sequential contrast-enhanced MR imaging of the penis 总被引:1,自引:0,他引:1
4.
Chlamydial etiology of acute lower respiratory tract infections in children in the Sudan 总被引:2,自引:0,他引:2
B Herrmann MAM Salih BE Yousif O Abdelwahab P-A Mårdh 《Acta paediatrica (Oslo, Norway : 1992)》1994,83(2):169-172
The role of Chlamydia pneumoniae in 110 Sudanese children with signs of acute lower respiratory tract infections (ALRI) was investigated. Four (3.6%) had evidence of C. pneumoniae infection, of whom 3 were culture-positive, while 1 had an antibody response suggesting a recent infection. IgG antibodies at a titer of ≥1:32 to C. pneumoniae, Chlamydia psittaci and Chlamydia trachomatis were detected in 27 (24.5%), 27 (24.5%) and 7 (6.4%) of the 110 ALRI cases, respectively. C. pneumoniae, C. trachomatis or C. psittaci were not detected in nasopharyngeal secretions from any of 110 patients when fluorescence-labeled specific monoclonal antibodies were used. In a seroepidemiological survey, 318 healthy Sudanese persons aged between 1 month and 67 years were studied for C. pneumoniae antibodies. 相似文献
5.
K B Isaacson M Amendola M Banner M Glassner S J Sondheimer 《International journal of fertility》1992,37(2):106-110
Over a 13-month period, 14 patients with proximal tubal obstruction underwent transcervical fallopian tube recanalization under fluoroscopic guidance in an outpatient setting at the hospital of the University of Pennsylvania. Twenty-one of 24 attempted tubal dilations (87.5%) were successful, as demonstrated by tubal opacification and contrast spillage into the peritoneal cavity at the conclusion of the procedure. Four intrauterine pregnancies, and no ectopic pregnancies, have followed the recanalization. One pregnancy ended in an early miscarriage, one patient delivered a healthy term female, and two pregnancies are ongoing at greater than twenty weeks' gestation. Two procedure-related complications occurred: in one patient, the isthmic segment of a fallopian tube was perforated, but healed without incident, and another patient experienced a low-grade fever, which resolved with p.o. antibiotics. We therefore conclude that fallopian tube recanalization is a well-tolerated, safe, and effective procedure for the treatment of proximal tubal occlusion. 相似文献
6.
P. VON DEN DRIESCH C. STEFFAN A. ZÖBE O.P. HORNSTEIN 《Clinical and experimental dermatology》1994,19(3):274-277
We report the case of a 39-year-old female patient suffering from Sweet's syndrome after an upper respiratory tract infection. Cyclosporin A at a dose of 10 mg/kg per day was given as initial treatment. Skin lesions and general malaise resolved within 9 days. The cyclosporin dose was decreased within 21 days, without recurrence of the eruption. Cyclosporin is a potent inhibitor of T lymphocytes, but affects granulocyte and monocyte functions as well. Success of treatment in our case shows that cyclosporin represents an alternative to steroid treatment in patients with Sweet's syndrome. 相似文献
7.
Comparison of LCx with other current viral load assays for detecting and quantifying human immunodeficiency virus type 1 RNA in patients infected with the circulating recombinant form A/G (CRF02) 下载免费PDF全文
Amendola A Bordi L Angeletti C Girardi E Ippolito G Capobianchi MR 《Journal of clinical microbiology》2004,42(2):811-815
LCx was compared to other assays in measuring human immunodeficiency virus type 1 (HIV-1) CRF02 viremia. LCx showed significant but low correlation with the other methods. Values of <2.60 log(10) cp/ml were observed in 29.6% of specimens with LCx and in only 14.8% with bDNA and PCR, suggesting suboptimal performance of LCx with CRF02. 相似文献
8.
Dynamic particle image velocimetry (PIV) was applied to the study of the flow field associated with prosthetic heart valves.
The results were compared with those of laser Doppler anemometry (LDA). Anatomically and antianatomically oriented Jyros (JR)
and St. Jude Medical (SJM) valves were compared in the mitral position to study the effects of valve design on the downstream
flow field. The experimental program used a dynamic PIV system utilizing high-speed, high-resolution video to map the true
time-resolved velocity field inside the simulated ventricle. This system was complemented by a study using the more traditional
LDA system for comparison. Based on the experimental data, the following general conclusions can be made. High-resolution
dynamic PIV can capture true chronological changes in the velocity and turbulence fields. It also produces very detailed velocity
and turbulence information comparable to the LDA results. In the vertical measuring plane that passes both the center of the
aortic and mitral valves (A-A section), the two valves (the SJM and the JR) show distinct circulatory flow patterns when the
valve is installed in the antianatomical orientation. Small differences in valve design can generate noticeable differences,
particularly during the accelerating flow phase. The SJM valve maintains a relatively high velocity through the central orifice;
the curved leaflets of the JR valve generate higher velocities with a divergent flow during the accelerating and peak flow
phases. In the velocity field directly below the mitral valve and normal to the previous measuring plane (B-B section), where
characteristic differences in valve design will be visible, symmetrical twin circulations were observed because of the divergent
nature of the flow generated by the two inclined half-disks installed in the antianatomical orientation. The SJM valve, with
a central downward flow near the valve, is contrasted with the JR valve, which has a peripheral downward circulation with
higher, turbulent stresses. 相似文献
9.
10.
Trisomy 8 in myelodysplasia and acute leukemia is constitutional in 15-20% of cases. 总被引:2,自引:0,他引:2
Emanuela Maserati Fiorenza Aprili Fabrizio Vinante Franco Locatelli Giovanni Amendola Adriana Zatterale Giuseppe Milone Antonella Minelli Franca Bernardi Francesco Lo Curto Francesco Pasquali 《Genes, chromosomes & cancer》2002,33(1):93-97
The trisomy 8 found in malignancies may derive from a constitutional trisomy 8 mosaicism (CT8M), and in these cases the trisomy itself may be regarded as the first mutation in a multistep carcinogenetic process. To assess the frequency of CT8M in hematological dysplastic and neoplastic disorders with trisomy 8, an informative sample of 14 patients was collected. The data ascertained included chromosome analyses of fibroblast cultures and of PHA-stimulated blood cultures in patients with normal blood differential count, as well as possible CT8M clinical signs. One patient showed trisomy 8 in all cell types analyzed and undoubtedly has a CT8M; a second patient consistently showed trisomy 8 in PHA-stimulated blood cultures when no immature myeloid cells were present in blood and should be considered as having CT8M; a third patient, with Philadelphia-positive chronic myelocytic leukemia, was more difficult to interpret, but the possibility that she had CT8M is likely. A few clinical signs of CT8M were also present in these three patients. Our data indicate that the frequency of CT8M in hematological dysplastic and neoplastic disorders with trisomy 8 is approximately 15-20%. 相似文献