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31.
Covering soft tissue defects remains challenging for orthopaedic surgeons, especially those in resource-challenged facilities. Covering tissue defects follow a plan from simple to complex: primary closure, local flap, area flap, pedicle flap, and free flap. I will limit my discussion to the role of latter two. At the district-level hospital in Vietnam, pedicle flaps are generally more useful, so I will discuss free flaps only briefly. The choices of pedicle flaps include: kite flap, posterior interosseous flap, radial flap (Chinese flap), neurocutaneous flap, anterolateral thigh fasciocutaneous flap, gastrocnemius flap, sural flap, posterior leg flaps; we typically use a free flap with the latissimus dorsi. Soft tissue coverage with pedicle flaps has many advantages: reliability, relatively easy harvest, and good blood supply. Free flaps with microanastomosis have an important place in covering difficult medium- or large-sized soft tissue defects but also require more instruments and more highly trained surgeons. The author certifies that he/she has no commercial associations (eg, consultancies, stock ownership, equity interest, patent/licensing arrangements, etc) that might pose a conflict of interest in connection with the submitted article. The author certifies that his/her institution does not require approval for the human protocol for this investigation and that the investigation was conducted in conformity with ethical principles of research.  相似文献   
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对以国际市场为主要目标市场的中药提取物产业化的背景、生产经营现状、有关政策法规、技术基础、市场前景以及中药提取物产业化的意义等方面进行探讨。  相似文献   
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目的:探讨钼靶X线检查在以簇状微小钙化为唯一征象的乳腺癌诊断中的意义。方法:34例乳腺病变患者先行钙化灶钼靶立体定位,细针穿刺注射美蓝染色,手术切除染色区域,切除标本取材,作冰冻切片及蜡片的病理诊断,比较良、恶性病变钙化的范围、单位面积(cm2)内钙化的数量以及钙化的形态、大小、分布,短期随访钙化数量的变化。结果:34例患者中乳腺癌18例,其中导管原位癌6例,早期浸润性癌4例,局部浸润性癌8例;良性乳腺病变16例。单位面积内钙化的数量:乳腺癌中83.33%〉20颗,良性病变中68.75%≤20颗;钙化类型:66.67%恶性病变为混合型,68.75%良性病变为细沙型;44.44%乳腺癌钙化的同时伴有导管分布,良性病变的钙化不伴导管分布;8例进行随访,4例钙化数量增多者均为乳腺癌,2例钙化数量减少者均为良性病变,2例钙化数量不变者,乳腺癌、良性病变各1例。结论:混合型簇状钙化、簇状钙化同时伴有导管分布、单位面积内钙化的数量大于20颗、短期内钙化数量增多,是乳腺癌的特征性钙化征象。  相似文献   
34.
目的探讨单核细胞向巨噬细胞分化过程中CD44 mRNA表达和黏附功能的变化。方法应用豆蔻佛波醇乙酯(PMA)诱导单核细胞系U937向巨噬细胞分化;应用RT-PCR分析U937细胞CD44 mRNA表达变化,并以β-actin作为内参进行半定量评价,并对主要条带进行测序;应用荧光染料BCECF/AM作为探针,测定黏附于激活的内皮细胞上的U937细胞数目。结果与对照组比较,PMA诱导的U937细胞CD44 mRNA总体表达显著增加(P=0.01037),异构体/标准CD44比例显著上升(P=0.0005551),测序结果显示PMA刺激后显著增加的是947 bp(V8 V9 V10)和1208 bp(V7 V8 V9 V10)CD44异构体。同时,PMA刺激后U937细胞黏附功能显著增加(P=0.0029)。结论单核细胞向巨噬细胞分化过程中CD44 mRNA,特别是947bp(V8 V9 V10)和1208 bp(V7 V8 V9 V10)CD44异构体的表达显著增加,可能与细胞黏附功能的增强相关。  相似文献   
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BACKGROUND/AIMS: Liver failure is a life threatening condition currently treated by palliative measures and, when applicable, organ transplantation. The use of a bioartificial organ capable of fulfilling the main functions of the liver would represent an attractive alternative. However, the shortage of suitable donor cells, and their limited growth ability have impeded the development of this strategy. We investigated whether lentiviral vectors allow for conditional immortalization of human hepatocytes and whether these immortalized hepatocytes could reverse lethal acute liver failure. METHODS: We exposed primary human hepatocytes to Cre-excisable lentiviral vectors coding for SV40T Antigen, telomerase, and/or Bmi-1 and tested the functionality of the resulting cell lines. Therapeutic potential of immortalized hepatocytes were tested in a murine model of acetaminophen-induced hepatic injury. RESULTS: The immortalized hepatocytes grew continuously yet were non-tumorigenic, stopped proliferating when exposed to Cre recombinase, and conserved defining properties of primary hepatocytes, including the ability to secrete liver-specific proteins and to detoxify drugs. The implantation of encapsulated immortalized human hepatocytes rescued mice from lethal doses of acetaminophen. CONCLUSIONS: Lentiviral vectors represent tools of choice for immortalization of non-dividing primary cells, and lentivirally immortalized human hepatocytes are promising reagents for cell-based therapy of acute liver failure.  相似文献   
38.
In Vietnam, the first three cases of Allo-BMT were successfully performed in 1995 at the Blood Transfusion and Hematology Hospital (BT-H) of Ho Chi Minh City. Donors were HLA fully matched siblings (HLA-A, HLA-B and HLA-DRB1). The patients were a 26-year-old man with CML in chronic phase (CP), a 12-year-old woman with beta-thalassemia/Hb E and a 9-year-old girl with beta-thalassemia/Hb E. All patients were engrafted with the median time to recover ANC>0.5 x 10(9)/l, and platelet count >20 x 10(9)/l was 16 and 38 days. At 12 years after transplantation, all three patients are alive and well. Today, Vietnam has five SCT centers; in the north, there are three centers: 108 Military Hospital, Pediatric Institute and Blood transfusion and Hematology Institute; in the middle of Vietnam is Hue Hospital and in the south, the BT-H Hospital of Ho Chi Minh City. Until now, 65 patients have had SCT in Vietnam; among them, 52 patients had SCT at the BT-H Hospital, Ho Chi Minh City. Because of no connection of data between different SCT centers, we present here only the results performed at the BT-H Hospital, Ho Chi Minh City. With Allo-SCT we performed 19 cases with 3 procedures: BMT (4 cases), PBSC (6 cases) and cord blood transplantation (9 cases); patients were diagnosed with AML (n=7), ALL (n=1), CML (n=5) and beta-thalassemia (n=6). Following transplantation, 7 patients (36.84%) relapsed, 12 (63.16%) remained alive and overall survival times: 6.81+/-1.35 years, disease-free survival times: 6.69+/-1.4 years (range 0.5-12 years). With Auto-SCT: since November 1996, we have performed 33 cases of autologous PBSC transplantation consisting of without cryopreservation (24 cases) and with cryopreservation (9 cases); patients were diagnosed with AML in CR1 (n=21), ALL in CR1 (n=6), CML in CP (n=5) and non-Hodgkin's lymphoma in CR1 (n=1). The median age of the patients was 35 years (range 18-46). The median time to recover ANC >0.5 x 10(9)/l and platelet count >20 x 10(9)/l was 14 days (range 9-25 days) and 35 days (range 9-120 days). Following transplantation, 18 patients (54.50%) relapsed, 15 (45.45%) remained alive and overall survival times: 5.74+/-0.82 years and disease-free survival times: 5.48+/-0.92 years. There was no statistically significant difference of overall survival and disease-free survival between Allo-SCT and Auto-SCT procedures (P>0.05). These preliminary data suggest that HSCTs have been used as one of the standard treatments for hematological diseases and malignancies in Vietnam and that cord blood is an alternative source of hematopoietic stem cells for allogeneic transplantation in children.  相似文献   
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Accurate measurements of HIV prevalence and associated risk factors among hidden and high-risk groups are vital for program planning and implementation. However, only two sampling methods are purported to provide representative estimates for populations without sampling frames: time-location sampling (TLS) and respondent-driven sampling (RDS). Each method is subject to potential biases and questionable reliability. In this paper, we evaluate surveys designed to estimate HIV prevalence and associated risk factors among people who inject drugs (PWID) sampled through TLS versus RDS. In 2012, males aged ≥16 years who reported injecting drugs in the previous month and living in Haiphong, Vietnam, were sampled using TLS or RDS. Data from each survey were analyzed to compare HIV prevalence, related risk factors, socio-demographic characteristics, refusal estimates, and time and expenditures for field implementation. TLS (n = 432) and RDS (n = 415) produced similarly high estimates for HIV prevalence. Significantly lower proportions of PWID sampled through RDS received methadone treatment or met an outreach worker. Refusal estimates were lower for TLS than for RDS. Total expenditures per sample collected and number of person-days of staff effort were higher for TLS than for RDS. Both survey methods were successful in recruiting a diverse sample of PWID in Haiphong. In Vietnam, surveys of PWID are conducted throughout the country; although the refusal estimate was calculated to be much higher for RDS than TLS, RDS in Haiphong appeared to sample PWID with less exposure to services and required fewer financial and staff resources compared with TLS.  相似文献   
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