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991.
Berend KR Hanna J Smith TM Mallory TH Lombardi AV 《Journal of surgical orthopaedic advances》2005,14(4):185-189
Arthroplasty for intertrochanteric fractures in elderly patients may allow early weightbearing and avoid fixation failure. Clinical results are reviewed in a consecutive group of acute arthroplasties (5 hemiarthroplasties and 29 total hip arthroplasties) performed via the anterolateral approach for intertrochanteric fractures. Age averaged 80.2 years. Follow-up averaged 35 months for living patients. Twenty-six patients died during follow-up. Time to death averaged 3.5 years. Five hips, all total hip arthroplasties, required subsequent surgeries: four for dislocation and one revised for sepsis. Acute intertrochanteric fractures are associated with high early mortality. In this series, a 15% complication rate and high mortality rate at 12 years was associated with acute arthroplasty. Dislocation is higher than in primary total hip arthroplasty utilizing the same surgical approach. The results do not support routine use of arthroplasty in treatment of intertrochanteric hip fractures in the elderly. 相似文献
992.
A proportion of chronic wounds fail to heal in response to standard therapy. For venous leg ulcers, a correlation exists between longer duration before treatment initiation and poor healing response to compression therapy. Differences identified between the healing wound microenvironment and that of the non healing chronic wound suggests that many potential mechanisms exist to impair healing. One contributory mechanism may be inhibition of fibroblast proliferation and induction of a stress-induced premature senescence phenotype by the continuing inflammation found in chronic wounds. Senescent fibroblasts exhibit an extracellular matrix degradative phenotype that contributes to wound chronicity. Accumulation of greater than 15% senescent fibroblasts has been described as a threshold beyond which wounds become hard to heal. The ratio of senescent : non senescent cells is therefore critical to determining response to treatment, and adjunctive therapies that modulate this ratio in favour of non senescent cells are likely to enhance therapeutic healing rates. A number of tissue-engineered dermal replacements contain non senescent fibroblasts and can donate cells to the wound environment additional to releasing growth factors and reversing the antiproliferative activity of chronic wound exudate. Recognition of the role of fibroblast senescence in wound chronicity may allow for identification of those wounds that will respond positively to these products. 相似文献
993.
Despite advances in molecular biology and a repertoire of other therapeutic options, chronic venous leg ulcers remain a significant problem within our society. There are various reasons, both local and systemic, which contribute to the non healing nature of such wounds. Among them, dystrophic calcification (DC) or calcified deposits within the ulcer bed, although rare, is an overlooked and a seldom reported cause. In the presence of DC, wound healing cannot proceed through a timely and orderly manner resulting in a non healing ulcer. In this article, we discuss the aetiology, pathophysiology and the management options of this rarely reported condition. We also report their clinical prognosis using a series of patients with venous ulcers complicated by DC leading to difficulties in healing. 相似文献
994.
Background Whilst it is well known that fractures of the pelvic rami in the elderly are frequently associated with posterior ring injuries, the extent of this second injury is less well known. We evaluated this question by MRI scanning a group of elderly patients presenting at our unit with pelvic rami fractures.
Patients and methods We investigated 50 consecutive elderly patients (45 women) with fractures of the pelvic rami using an MRI scan of the pelvis in order to assess the competency of the pelvic ring.
Results On MRI, 45 (95% CI 42-48) patients had a sacral fracture. At 5-month follow-up, 39 (of 41 reviewed) still complained of posterior sacral tenderness.
Interpretation Pelvic rami fractures in the elderly are nearly always associated with posterior ring injuries. This probably explains why these patients take longer to rehabilitate than might be expected if only the anterior injury is considered, and it also explains why they experience long-term back pain. 相似文献
Patients and methods We investigated 50 consecutive elderly patients (45 women) with fractures of the pelvic rami using an MRI scan of the pelvis in order to assess the competency of the pelvic ring.
Results On MRI, 45 (95% CI 42-48) patients had a sacral fracture. At 5-month follow-up, 39 (of 41 reviewed) still complained of posterior sacral tenderness.
Interpretation Pelvic rami fractures in the elderly are nearly always associated with posterior ring injuries. This probably explains why these patients take longer to rehabilitate than might be expected if only the anterior injury is considered, and it also explains why they experience long-term back pain. 相似文献
995.
Micronutrient deficiencies in early pregnancy are common, concurrent, and vary by season among rural Nepali pregnant women 总被引:2,自引:0,他引:2
Pregnant women in developing countries are vulnerable to multiple micronutrient deficiencies. We investigated their prevalence and seasonal variation as part of a baseline assessment in a population-based, maternal micronutrient supplementation trial conducted in the rural Southeastern plains of Nepal. Serum concentrations of 11 micronutrients were assessed in 1165 pregnant women in the 1st trimester before supplementation. Using defined cutoff values, the prevalence of deficiencies of vitamins A, E, and D were 7, 25, and 14%, respectively. Nearly 33% of the women were deficient in riboflavin, and 40 and 28% had serum vitamin B-6 and B-12 deficiencies, respectively. Only 12% of the women were folate deficient, but 61% were zinc deficient. The prevalence of low serum iron concentration was 40%, and 33% were anemic (hemoglobin < 110 g/L). Multiple micronutrient deficiencies were common among pregnant women. Over 10% of the pregnant women were both anemic and deficient in B-complex vitamins, whereas 22% of women were both anemic and zinc deficient. Only 4% of women had no deficiency, whereas approximately 20% of the women had 2, 3, or 4 deficiencies. Almost 18% of women had >/=5 deficiencies. Micronutrient status varied by season; it was generally best during the winter months, except for serum vitamin D concentration, which peaked during the hot summer and monsoon months. Women in rural South Asia are likely to begin a pregnancy with multiple micronutrient deficiencies that may vary with seasonality in micronutrient-rich food availability. 相似文献
996.
The trinuclear complex: [{trans-PtCl(NH(3))}(2)mu-{trans-Pt(NH(3))(2-hydroxypyridine)-(H(2)N(CH(2))(6)NH(2))(2)]Cl(4) (code named CH9) has been synthesized and characterized. The activity of the compound against human ovarian cancer cell lines: A2780, A2780(cisR) and A2780(ZD0473R), cell up take, level of binding with DNA and nature of its interaction with pBR322 plasmid DNA have been determined. Although the compound is found to be less active (about a half time as active as cisplatin) against the parent ovary cell line A2780, it is found to be more active than cisplatin against resistant cell lines: A2780(cisR) (3.6 times more) and A2780(ZD0473R) (3.4 times more). The higher activity of CH9 against the resistant cell lines suggests that the compound has been able to overcome multiple mechanisms of resistance operating in A2780(cisR) and A2780(ZD0473R) cell lines. Like other multicentered complexes, the compound is believed to form a range of interstrand GG adducts with duplex DNA that induces permanent global changes in the DNA conformation. This binding is different from that of cisplatin and ZD0473 that form mainly intrastrand adducts, inducing a local kink in a DNA strand. Increasing prevention of BamH1 digestion of form I and form II pBR322 plasmid DNA with the increase in concentration of CH9 provides support to the idea that global changes in DNA conformation are induced as a result of its interaction with the compound. 相似文献
997.
Madhi SA Kuwanda L Saarinen L Cutland C Mothupi R Käyhty H Klugman KP 《Vaccine》2005,23(48-49):5517-5525
The quantitative (anti-Hib capsular polysaccharide antibody concentrations; anti-HibPS) and qualitative (bactericidal activity and avidity) aspects in immune responses to Haemophilus influenzae type b polyribosyl ribitol phospshate-CRM(197) conjugate vaccine (HibCV; HibTiter) were evaluated in 66 HIV infected children not receiving anti-retroviral therapy and 127 HIV uninfected children. Surveillance was conducted for invasive Hib disease in a cohort of 39,865 (approximately 6.4% of whom were HIV infected) children from March 1998 to June 2004. HIV infected children had lower anti-HibPS geometric mean antibody concentrations 1 month post-immunisation than HIV uninfected children (P<0.00001) and were less likely to have anti-HibPS antibody concentrations of >or=1.0 microg/ml (RR 0.54; 95% CI 0.43-0.69). A lower proportion of HIV infected children than HIV uninfected children (RR 0.78; 95% CI 0.66-0.93) had measurable anti-Hib serum bactericidal activity (SBA) and the HibPS antibody concentration required for 50% killing of Hib bacteria was greater among HIV infected than HIV uninfected children (P=0.001). The estimated risk of HibCV failure was 35.1-fold greater (95% CI 14.6-84.6) amongst HIV infected than HIV uninfected children. 相似文献
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