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71.
Islet transplantation offers patients with type 1 diabetes mellitus freedom from long-term insulin therapy and a degree of metabolic control that is far superior to injected insulin. The hope is that near-perfect glucose control sustained over time will prevent progression of secondary diabetic complications. The selection of optimal immunosuppressive agents for islet transplantation has been a formidable challenge, given the need to overcome both autoimmune and alloimmune barriers, as well as the potential toxicity of immunosuppressive agents on transplanted islets. Early strategies relied on protocols that had proven success in solid organ transplantation and consisted of azathioprine, cyclosporine and corticosteroids. Under these protocols, fewer than 10% of patients were able to achieve insulin independence. The development of the 'Edmonton Protocol' dramatically transformed clinical outcomes in islet transplantation in recent years through the introduction of a more potent, less diabetogenic, and corticosteroid-free immunosuppressive regimen consisting of sirolimus, low-dose tacrolimus, and induction anti-interleukin-2 receptor antibody. While insulin independence rates under this protocol have been highly successful, patients must be maintained on lifelong immunosuppression. While the risk of malignancy, post-transplant lymphoma and sepsis have been low and diminishing in transplanted patients to date, fears of these complications and a host of drug-related adverse effects have precluded broader application. Patients undergoing islet transplantation today must exchange insulin for chronic immunosuppressive therapy, and therefore the procedure can only be justified in patients with very unstable forms of diabetes, or in those with another solid organ allograft who already endure the risks of immunosuppression. Advances in more specific and less toxic immunosuppressive agents together with progress in better understanding the biology of diabetes will lead to more suitable strategies to control both alloimmune and recurrent autoimmune reactions. These protocols, ultimately aimed at establishing tolerance, are an essential pre-requisite to move towards providing islet transplantation earlier in the course of the disease, including transplantation in children. This review addresses the evolution of immunosuppressive strategies in islet transplantation, and highlights some novel agents in pre-clinical development or in early clinical trials that may offer considerable promise in facilitating the induction of tolerance.  相似文献   
72.
73.
We conducted a cleaning trial in 40 northern New Jersey homes where home renovation and remodeling (R&R) activities were undertaken. Two cleaning protocols were used in the study: a specific method recommended by the US Department of Housing and Urban Development (HUD), in the 1995 "Guidelines for the Evaluation and Control of Lead-Based Paint Hazards in Housing," using a high-efficiency particulate air (HEPA)-filtered vacuum cleaner and a tri-sodium phosphate solution (TSP); and an alternative method using a household vacuum cleaner and a household detergent. Eligible homes were built before the 1970s with potential lead-based paint and had recent R&R activities without thorough cleaning. The two cleaning protocols were randomly assigned to the participants' homes and followed the HUD-recommended three-step procedure: vacuuming, wet washing, and repeat vacuuming. Wipe sampling was conducted on floor surfaces or windowsills before and after cleaning to evaluate the efficacy. All floor and windowsill data indicated that both methods (TSP/HEPA and non-TSP/non-HEPA) were effective in reducing lead loading on the surfaces (P < 0.001). When cleaning was applied to surfaces with initial lead loading above the clearance standards, the reductions were even greater, above 95% for either cleaning method. The mixed-effect model analysis showed no significant difference between the two methods. Baseline lead loading was found to be associated with lead loading reduction significantly on floors (P < 0.001) and marginally on windowsills (P = 0.077). Such relations were different between the two cleaning methods significantly on floors (P < 0.001) and marginally on windowsills (P = 0.066), with the TSP/HEPA method being favored for higher baseline levels and the non-TSP/non-HEPA method for lower baseline levels. For the 10 homes with lead abatement, almost all post-cleaning lead loadings were below the standards using either cleaning method. Based on our results, we recommend that contractors or homeowners can use a household vacuum cleaner and a household detergent to clean lead-contaminated environments after R&R activities when HUD-recommended equipment is not available.  相似文献   
74.
The ethanol extract of leaves of Piper porphyrophyllum N.E. Br. showed a broad spectrum of antibacterial activity. The activity was increased on fractionation (hexane, dichloromethane and aqueous), particularly in the aqueous fraction. No activity was shown against tested Candida albicans.  相似文献   
75.
The management of Scimitar syndrome in adulthood is controversial, with no guidelines for surgical correction. We present the case of a 66-year-old woman who presented late in life with Scimitar syndrome and a significant left-to-right shunt. We describe repair using an intra-atrial conduit from the anomalous vein to the foramen ovale, with a successful outcome.  相似文献   
76.
BACKGROUND: The relationship between pregnancy and typhoid fever is not well defined. The objective of this study was twofold: to assess the effect of the pregnant and postpartum host on typhoid disease expression, and to explore the relationship between typhoid fever and pregnancy outcome. METHODS: Over an 11-year period, all 181 adult women with blood culture-confirmed typhoid fever admitted to a university hospital in Karachi, Pakistan were studied; those with pregnancy-related disease were compared to the non-pregnant women. The relationship between typhoid fever and pregnancy outcome was evaluated by comparing 80 pregnant women with typhoid, with 194 randomly selected pregnant women without typhoid who were matched for age and study year. RESULTS: In adult females with bacteremic typhoid disease, a significant proportion was pregnancy-related (47%). These women were less likely to have other co-morbid illnesses (2% vs. 27%, p<0.001) and were almost exclusively treated with ampicillin/amoxicillin or third-generation cephalosporins, while the non-pregnant women with typhoid fever preferentially received quinolones. The mean duration of antimicrobial therapy was similar in both groups (14 days) but the non-pregnant group defervesced earlier (4.2 days vs. 5.6 days, p=0.011). Complications of typhoid fever were significantly more likely in the non-pregnant group (23% vs. 8%, p=0.005) and primarily involved lower gastrointestinal bleeding. On comparing the pregnant women with typhoid with randomly selected age-matched pregnant women without typhoid, there were no apparent effects of typhoid fever on pregnancy outcome as measured by gestational age at delivery, pregnancy complications, modes of delivery, neonate gender, birth weight, or birth Apgar scores. CONCLUSIONS: While pregnancy is a risk factor for and effects typhoid disease expression, typhoid fever does not appear to affect pregnancy outcome.  相似文献   
77.
Resection and reconstruction using a vascularised fibular graft is a viable alternative treatment for congenital pseudarthrosis of the tibia, although distal junctional nonunion and residual deformity are known complications that are difficult to treat. We illustrate 2 cases in which bony union was achieved following a technique using fibular grafting and intramedullary nailing, without additional bone grafting. This technique was feasible because of hypertrophy of the fibular graft.  相似文献   
78.

Background

In 2006, 4 years of planning was started by the Ministry of Health, Malaysia (MOH), to implement the HPV (human papillomavirus) vaccination programme. An inter-agency and multi-sectoral collaborations were developed for Malaysia’s HPV school-based immunisation programme. It was approved for nationwide school base implementation for 13-year-old girls or first year secondary students in 2010. This paper examines how the various strategies used in the implementation over the last 7?years (2010–2016) that unique to Malaysia were successful in achieving optimal coverage of the target population.

Methods

Free vaccination was offered to school girls in secondary school (year seven) in Malaysia, which is usually at the age of 13 in the index year. All recipients of the HPV vaccine were identified through school enrolments obtained from education departments from each district in Malaysia. A total of 242,638 girls aged between 12 to 13?years studying in year seven were approached during the launch of the program in 2010. Approximately 230,000 girls in secondary schools were offered HPV vaccine per year by 646 school health teams throughout the country from 2010 to 2016.

Results

Parental consent for their daughters to receive HPV vaccination at school was very high at 96–98% per year of the programme. Of those who provided consent, over 99% received the first dose each year and 98–99% completed the course per year. Estimated population coverage for the full vaccine course, considering also those not in school, is estimated at 83 to 91% per year. Rates of adverse events reports following HPV vaccination were low at around 2 per 100,000 and the majority was injection site reactions.

Conclusion

A multisectoral and integrated collaborative structure and process ensured that the Malaysia school-based HPV immunisation programme was successful and sustained through the programme design, planning, implementation and monitoring and evaluation. This is a critical factor contributing to the success and sustainability of the school-based HPV immunisation programme with very high coverage.
  相似文献   
79.

Background

Bipolar hip hemiarthroplasty is used in the management of fractures of the proximal femur. The dual articulation is cited as advantageous in comparison to unipolar prostheses as it decreases acetabular erosion, has a lower dislocation rates and is easier to convert to a total hip arthroplasty (THA) should the need arise. However, these claims are debatable. Our study examines the rate of conversion of the bipolar hemiarthroplasty to THA and the justification for using it on the basis of future conversion to THA.

Methods

All cases of bipolar hemiarthroplasty performed in our unit for hip fractures over a 9-year period (1999-2007) were reviewed. Medical notes and radiographs of all patients were reviewed, and all surviving patients that were contactable received a telephone follow-up.

Results

Of all 164 patients reviewed with a minimum of 1 year from date of surgery, 4 patients had undergone a conversion of their bipolar prosthesis to THA. Three conversions were performed for infection, dislocation, and fracture. Only one (0.6%) conversion was performed for groin pain.

Conclusions

Our study show that bipolar hemiarthroplasties for hip fractures have a low conversion rate to THAs and this is comparable to the published conversion rate of unipolar hemiarthroplasties.  相似文献   
80.
AIM: The objective of this article is to present a simple technique for stabilizing a lingual fixed retainer wire in place with good adaptation to the teeth surfaces and checking for occlusal interferences prior to the bonding procedure. BACKGROUND: Bonding of an upper or lower fixed lingual retainer using stainless steel wires of different sizes and shapes is a common orthodontic procedure. The retainer can be constructed in a dental laboratory, made at chair side, or it can be purchased in prefabricated form. All three ways of creating a fixed retainer are acceptable. However, the method of holding the retainer wire in place adjacent to the lingual surfaces of the teeth before proceeding with the bonding process remains a problem for some practitioners. REPORT: The lingual fixed retainer was fabricated using three pieces of .010" steel ligature wire which were twisted into a single strand wire. Another four to five 0.010" pieces of steel ligature wires were twisted in the same way to serve as an anchor wire from the labial side of the teeth. The retainer wire was bonded using the foible composite. SUMMARY: The technique presented here for stabilizing the retainer wire prior to bonding provides good stabilization, adaptation, and proper positioning of the retainer wire while eliminating contamination of etched surfaces which might arise during wire positioning before bonding. This technique also allows the clinician the opportunity to check the occlusion and adjust the retainer wire to avoid occlusal interference prior to bonding maxillary retainers. This same clinical strategy can be used to stabilize wires for splinting periodontally affected teeth and traumatized teeth.  相似文献   
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