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61.
Peripheral blood lymphocytes (PBLs) from multiple myeloma patients are defective in both proportion and absolute numbers of OKT4+ cells and have a normal proportion but reduced absolute number of OKT8+ cells. To assess the functional capabilities of the T cells in myeloma patients, we cloned the T cells in PBLs using limiting dilution conditions in which 100% of OKT4+ and OKT8+ T cells in normal PBLs are able to form a clone. In contrast, the OKT8+ cells from PBLs of five of seven multiple myeloma patients were severely compromised in their clonogenic potential; only 7% to 25% of OKT8+ T cells appeared to give rise to a clone. Clonogenic potential of the OKT4+ cells in patients was more nearly normal. Analysis of two multiple myeloma patients with abnormally low numbers of T cells in PBLs revealed the existence of abnormalities in the progenitors of T cell clones. In both patients, two to three times as many T cell clones were observed as would have been expected based on the number of PBLs cultured at limiting dilution, indicating that OKT4-8- cells in PBLs are capable of giving rise to OKT4+ and, at lower frequency, to OKT8+ clonal progeny in vitro. We conclude that purely quantitative assessment of T cell subsets should be interpreted with caution, since proportionately normal numbers of OKT8+ cells in patient PBLs are seriously compromised in their ability to give rise to clonal progeny in vitro, and since there appears to be a OKT4-8- population of T cells in PBLs that are committed to become OKT4+ or OKT8+ T cells, but are unable to do so in vivo. 相似文献
62.
63.
Versatility of the distally based superficial sural flap for reconstruction of lower leg and foot in children 总被引:2,自引:0,他引:2
Koladi J Gang RK Hamza AA George A Bang RL Rajacic N 《Journal of pediatric orthopedics》2003,23(2):194-198
Twenty children are presented after undergoing a distally based superficial sural flap for coverage of defects at the lower leg and foot. The age of the patients was between 1 and 12 years. Fifteen patients had trauma to the lower leg, with eight of them having associated injuries. Three had postburn contracture and two had pressure sore. In 14 cases, the flap was used as a fasciocutaneous flap, whereas in six cases it was used as a fascial flap covered with a skin graft. The flaps were used to cover the defects from the dorsum of the foot distally up to the mid third of tibia proximally. The mean follow-up was for a period of 2 years. Even though free tissue transfer is reliable and safe for the reconstruction of major leg injuries in children, the distally based superficial sural flap has the advantage of being easy to perform, with short operating time, minimal donor side morbidity, and preservation of major arteries of the leg. 相似文献
64.
Frank Lindseth Thomas Lang? Jon Bang Toril A Nagelhus Hernes 《Computer aided surgery》2002,7(4):197-222
65.
Full exposure of the medial orbital wall for fracture repair poses difficulty with traditional approaches except coronal incision, especially in cases of wide fracture. The endoscopic-assisted approach with limited incision has been introduced. The authors used the endoscopically assisted transconjunctival approach in 21 cases: 15 isolated medial orbital wall fractures and 6 cases of concomitant floor fractures. Through the medial transconjunctival slit incision, repair of the fracture using calvarial bone graft was undertaken with the aid of an endoscope. All patients recovered without any eye symptoms including clinically notable enophthalmos, but one immediate revisional operation was needed because of a displaced bone graft. Otherwise, the desired position of the graft was confirmed via computed tomography. The endoscopically assisted transconjunctival approach to the orbital medial wall provides improved surgical exposure of the most posterior and superior aspects of the fracture site, enabling more accurate reduction of orbital soft tissue and placement of bone grafts. 相似文献
66.
Bum Soon Choi Mi Jung Shin Suk Joon Shin Young Soo Kim Yeong Jin Choi Yong-Soo Kim In Sung Moon Suk Young Kim Yong Bok Koh Byung Kee Bang Chul Woo Yang 《American journal of transplantation》2005,5(6):1354-1360
We report here our 10-year experience of a biopsy performed at day 14 after transplantation in 304 patients with stable graft function. The factors that may have influenced subclinical rejection were analyzed according to histology. The incidence of subclinical rejection was 13.2%. Addition of mycophenolate mofetile (MMF) as a primary immunosuppressant significantly decreased the incidence of subclinical rejection compared with patients without such treatment (odds ratio, 0.23; p < 0.05). On the other hand, HLA-DR antigen mismatch (odds ratio, 2.39) and unrelated donor (odds ratio, 2.10) were also significantly associated with decreased subclinical rejection (p < 0.05). The incidence of acute rejection in patients with normal findings was lower than in those with borderline changes or subclinical rejection (0.23 +/- 0.05 vs. 0.48 +/- 0.07 and 0.60 +/- 0.11, respectively; p < 0.05). The graft survival rates in patients with subclinical rejection were lower than in patients with normal or borderline changes at 1 (88.4% vs. 97.9% and 99.1%; p < 0.05), 5 (77.8% vs. 96.2% and 95.9%; p < 0.05) and 10 (62.3% vs. 96.2% and 93.7%; p < 0.05) years. Thus, a protocol biopsy performed on day 14 after transplantation is useful for predicting graft survival. Triple therapy including MMF, related donor and HLA-DR antigen match are important factors for reducing subclinical rejection in living-donor renal transplantation. 相似文献
67.
Objective To detect new mutations among 29 glucose-6-phosphate dehydrogenase (G6PD) deficient individuals from Yunnan province. Methods The nitroblue tetrazolium (NBT) method was used to screen G6PD deficient individuals. Mutation was identified by single strand conformation polymorphism (SSCP), amplification created restriction site (ACRS), amplification refractory mutation system (ARMS) and DNA sequencing. Results Among 29 cases, 18 cases of G1388A, 1 case of C1004A, and 1 case of G1381A were identified. Nine cases remained to be defined. The G1381A mutation is a novel mis-sense mutation, with a substitution of threonine for alanine (A461T). The resultant G6PD had reduced enzymatic activity. In addition, G1381A caused a restriction site of Stu I to disappear, providing a rapid method for the detection of this mutation. Conclusion A novel mis-sense mutation G1381A was found. This mutation results in a substitution of threonine for alanine, producing enzyme with reduced activity. The loss of the Stu I restriction site offers a rapid method for the detection of this mutation. 相似文献
68.
目的:利用组织培养方法快速繁殖成米麻作为种麻,为寻找出一简便可行的快繁天麻种麻的新途径提供理论依据。方法:天麻块茎或茎尖无菌离体培养,米麻块茎诱导培养基为1/2MS+6-BA 1mg/L NAA0.5mg/L+香蕉50mg/L;箭麻茎尖诱导培养基为1/2MS+6-BA2mg/L NAAO.2mg/L。结果:小米麻经50d无菌培养后开始生长出新米麻,70d后原小米麻块茎上生长出多个分枝的新米麻;箭麻茎尖超过140d组织培养,茎尖分化、诱导形成原球茎,超过160d培养原球长大并开花。结论:天麻可以用组织培养方法快速繁殖成米麻作为种麻。 相似文献
69.
Shin JW Park NH Park JH Park JH Jeong ID Bang SJ Joo KR Kim DH 《Journal of viral hepatitis》2005,12(4):393-397
The efficacy of lamivudine re-treatment in chronic hepatitis B (CHB) patients who relapse after HBeAg seroconversion with lamivudine has not been investigated. The aim of this study was to evaluate the efficacy of lamivudine re-treatment in relapsed patients. Among 192 patients who had achieved HBeAg seroconversion with lamivudine at a dose of 100 mg/day, 121 patients discontinued lamivudine. Relapse occurred in 49 patients (40.5%). Thirty-three relapsed patients received lamivudine re-treatment for at least 6 months. The mean duration of lamivudine re-treatment was 16 months and the follow-up period was 8.9 months. HBeAg seroconversion was achieved in 23 patients (69.7%). The cumulative HBeAg seroconversion rates at 5, 9, and 12 months were 60, 64, and 67%, respectively. The mean time to HBeAg seroconversion in lamivudine re-treatment was shorter than that in the initial therapy (4.7 months vs. 9.7 months). Viral breakthrough occurred in six (18.2%) patients. All patients with viral breakthrough were accompanied by elevation of serum alanine aminotransferase (ALT) levels. Among 15 patients who discontinued lamivudine re-treatment after HBeAg seroconversion, relapse occurred in six patients (40%). All relapses occurred within 9 months after the discontinuation of lamivudine re-treatment. In conclusion, lamivudine re-treatment in relapsed patients after initial lamivudine therapy had a higher response rate and shorter duration to HBeAg seroconversion than during the initial therapy. However, HBeAg seroconversion induced by lamivudine re-treatment was not durable. 相似文献
70.
Effects of fenofibrate on high-fat diet-induced body weight gain and adiposity in female C57BL/6J mice 总被引:3,自引:0,他引:3
Jeong S Han M Lee H Kim M Kim J Nicol CJ Kim BH Choi JH Nam KH Oh GT Yoon M 《Metabolism: clinical and experimental》2004,53(10):1284-1289
Our previous study suggested that fenofibrate affects obesity and lipid metabolism in a sexually dimorphic manner in part through the differential activation of hepatic peroxisome proliferator-activated receptor alpha (PPARalpha) in male and female C57BL/6J mice. To determine whether fenofibrate reduces body weight gain and adiposity in female sham-operated (Sham) and ovariectomized (OVX) C57BL/6J mice, the effects of fenofibrate on not only body weight, white adipose tissue (WAT) mass, and food intake, but also the expression of both leptin and PPARalpha target genes were measured. Compared to their respective low-fat diet-fed controls, both Sham and OVX mice exhibited increases in body weight and WAT mass when fed a high-fat diet. Fenofibrate treatment decreased body weight gain and WAT mass in OVX, but not in Sham mice. Furthermore, fenofibrate increased the mRNA levels of PPARalpha target genes encoding peroxisomal enzymes involved in fatty acid beta-oxidation, and reduced apolipoprotein C-III (apo C-III) mRNA, all of which were expressed at higher levels in OVX compared to Sham mice. However, leptin mRNA levels were found to positively correlate with WAT mass, and food intake was not changed in either OVX or Sham mice following fenofibrate treatment. These results suggest that fenofibrate differentially regulates body weight and adiposity due in part to differences in PPARalpha activation, but not to differences in leptin production, between female OVX and Sham mice. 相似文献