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21.
22.
Sze-Hon Chua  MRCP    Por Ang  MRCP    Lawrence S. W. Khoo  MRCP    Chee-Leok Goh  FRCP 《Dermatologic surgery》2004,30(10):1287-1291
BACKGROUND: There is presently little published data on the clinical effectiveness of nonablative lasers in the treatment of atrophic acne scars and the safety of their use in patients with darker skin types. OBJECTIVE: This study aims to determine the clinical effectiveness and safety of the nonablative 1450 nm diode laser with cryogen cooling spray in the treatment of facial atrophic acne scars in Type IV-V Asian skin. METHODS: This is a prospective non-comparative open study. 4 to 6 laser treatment sessions were performed on patients with atrophic acne scars. Final clinical assessment was performed 6 months after the last treatment. RESULTS: 57 patients were evaluated. Patient's self-assessment of scar improvement as compared with doctor's assessment was as follows: patients who completed 4 treatments (15.7% vs 6.6%), patients who completed 5 treatments (20% vs 7.9%) and patients those who completed 6 treatments (17.3% vs 5.0%). Main side effects were mild to moderate pain during the procedure, transient erythema, and hyperpigmentation which occurred in 39% of treated patients. CONCLUSION: The nonablative 1450 nm diode laser may be effective in achieving mild to moderate gradual clinical improvement in the treatment of facial atrophic acne scars. The procedure is associated with minimal downtime and is safe for use in darker skin types IV and V.  相似文献   
23.
Little information exists regarding the efficacy, modifiers, and outcomes of anemia management in children with CKD or ESRD. We assessed practices, effectors, and outcomes of anemia management in 1394 pediatric patients undergoing peritoneal dialysis (PD) who were prospectively followed in 30 countries. We noted that 25% of patients had hemoglobin levels below target (<10 g/dl or <9.5 g/dl in children older or younger than 2 years, respectively), with significant regional variation; levels were highest in North America and Europe and lowest in Asia and Turkey. Low hemoglobin levels were associated with low urine output, low serum albumin, high parathyroid hormone, high ferritin, and the use of bioincompatible PD fluid. Erythropoiesis-stimulating agents (ESAs) were prescribed to 92% of patients, and neither the type of ESA nor the dosing interval appeared to affect efficacy. The weekly ESA dose inversely correlated with age when scaled to weight but did not correlate with age when normalized to body surface area. ESA sensitivity was positively associated with residual diuresis and serum albumin and inversely associated with serum parathyroid hormone and ferritin. The prevalence of hypertension and left ventricular hypertrophy increased with the degree of anemia. Patient survival was positively associated with achieved hemoglobin and serum albumin and was inversely associated with ESA dose. In conclusion, control of anemia in children receiving long-term PD varies by region. ESA requirements are independent of age when dose is scaled to body surface area, and ESA resistance is associated with inflammation, fluid retention, and hyperparathyroidism. Anemia and high ESA dose requirements independently predict mortality.Almost three decades after the advent of recombinant erythropoietin, the management of renal anemia has become a recent focus of attention and changing paradigms. Whereas correction of hemoglobin (Hb) levels to near-normal has previously been recommended on the basis of association studies linking more severe anemia to morbidity and mortality with dialysis,13 interventional clinical trials consistently demonstrate that near-normalization of Hb increases the risk of vascular events and mortality in adults receiving maintenance hemodialysis and in those with CKD who are not undergoing dialysis.46 This has prompted ongoing reevaluation and revisions of treatment targets in patients exposed to erythropoiesis-stimulating agents (ESAs).7The appropriateness of applying treatment recommendations established in adult hemodialysis populations at high cardiovascular risk and adults with CKD to children undergoing dialysis is questionable because cardiovascular events are far less common in children with CKD. Furthermore, two thirds of children requiring dialysis initially opt for peritoneal dialysis (PD), and there are no systematic studies in the adult PD population to inform the optimal Hb target range in these patients. The risk profile of patients receiving PD may differ from that of the hemodialysis setting because of the absence of dialysis-induced intermittent hemoconcentration and lack of contact activation of the complement and coagulation systems.Further aspects to consider in pediatric anemia management are the greater physical activity of children and the need for optimal cognitive functioning at school.8,9 The significant physiologic variation of the normal Hb range with age10 and the relative ESA sensitivity that reportedly increases with age during early childhood are also noteworthy.11The registry of the International Pediatric Peritoneal Dialysis Network (IPPN) prospectively collects detailed clinical, biochemical, dialysis, and medication-related information (including ESA types and doses and modalities of iron supplementation) from a substantial number of children undergoing long-term PD around the world. In-depth analysis of this unique database has allowed us to (1) gain insight into the demographic characteristics of renal anemia and its treatment in the pediatric PD population worldwide, (2) explore the relationship between ESA dose requirements and body dimensions, (3) identify factors contributing to ESA resistance in children, and (4) associate anemia control with patient outcomes.  相似文献   
24.

Background  

We investigated the implications of HER2 amplification in Asian women with small, node-negative breast cancer in low- and middle-income countries (LMCs).  相似文献   
25.

Background  

The purpose of this study was to compare the outcome of robot-assisted transaxillary thyroid surgery (RATS) to the standard open technique for thyroid lobectomy in the U.S. population.  相似文献   
26.
In most Western countries, screening mammography and breast-conserving therapy (BCT) are now well-established practices and have been well accepted by women over the last two decades. There are limited data on the acceptability of these strategies by Chinese women in an Oriental society where a population-based screening program has not been established and mastectomy is still commonly practiced. A survey was conducted of 1012 Hong Kong Chinese women, ages 18-69 years, to assess the level of knowledge, perceptions, and attitudes on screening mammography and the surgical management of early breast cancer. Most women (58%) had never heard of mammographic screening, and housewives were more likely to have heard of it than nonhousewives (49% versus 37%; p = 0.0001). The majority (82%) of those who had heard of mammographic screening believe that it can detect early breast cancers and reduce mortality, however, only 58% of these women would participate in yearly screening and clinical breast examination despite acknowledging the potential benefits; a lack of time and the cost were the predominant reasons given. Forty-seven percent of women had the misconception that mastectomy was the only curative treatment; when the alternative was explained, the overall rate for choosing BCT rose from 29% to 49%. There was no correlation between age and the choice of surgery. Most women (75%) felt that breast reconstruction after mastectomy was desirable and acceptable. A lack of knowledge on mammographic screening is prevalent and the concept of preventive health care has a low priority in this Chinese population. Mastectomy is still widely perceived as the only curative treatment; BCT with cosmetic reconstruction is seen as an acceptable alternative. Interventions to improve the accuracy of information and to encourage preventive health care behaviors will have a positive impact on establishing cancer screening programs and providing quality cancer care in the future.  相似文献   
27.

Purpose

The aim of this study was to determine whether errors do occur in navigated total knee arthroplasty (TKAs) and to study whether errors in bone resection or implantation contribute to these errors.

Methods

A series of 20 TKAs was studied using computer navigation. The coronal and sagittal alignments of the femoral and tibial cutting guides, the coronal and sagittal alignments of the final tibial implant and the coronal alignment of the final femoral implant were compared with that of the respective bone resections. To determine the post-implantation mechanical alignment of the limb, the coronal alignment of the femoral and tibial implants was combined.

Results

The median deviation between the femoral cutting guide and bone resection was 0° (range ?0.5° to +0.5°) in the coronal plane and 1.0° (range ?2.0° to +1.0°) in the sagittal plane. The median deviation between the tibial cutting guide and bone resection was 0.5° (range ?1.0° to +1.5°) in the coronal plane and 1.0° (range ?1.0° to +3.5°) in the sagittal plane. The median deviation between the femoral bone resection and the final implant was 0.25° (range ?2.0° to 3.0°) in the coronal plane. The median deviation between the tibial bone resection and the final implant was 0.75° (range ?3.0° to +1.5°) in the coronal plane and 1.75° (range ?4.0° to +2.0°) in the sagittal plane. The median post-implantation mechanical alignment of the limb was 0.25° (range ?3.0° to +2.0°).

Conclusions

When navigation is used only to guide the positioning of the cutting jig, errors may arise in the manual, non-navigated steps of the procedure. Our study showed increased cutting errors in the sagittal plane for both the femur and the tibia, and following implantation, the greatest error was seen in the sagittal alignment of the tibial component. Computer navigation should be used not only to guide the positioning of the cutting jig, but also to check the bone resection and implant position during TKA.

Level of evidence

IV.  相似文献   
28.

Background

This study aims to quantify changes in fibroblast growth factor 19 (FGF19) and bile acids (BAs) in patients with uncontrolled type 2 diabetes randomized to Roux-en-Y gastric bypass (RYGB) vs intensive medical management (IMM) and matched for similar reduction in HbA1c after 1 year of treatment.

Methods

Blood samples were drawn from patients who underwent a test meal challenge before and 1 year after IMM (n?=?15) or RYGB (n?=?15).

Results

Mean HbA1c decreased from 9.7 to 6.4 % after RYGB and from 9.1 to 6.1 % in the IMM group. At 12 months, the number of diabetes medications used per subject in the RYGB group (2.5?±?0.5) was less than in the IMM group (4.6?±?0.3). After RYGB, FGF19 increased in the fasted (93?±?15 to 152?±?19 pg/ml; P?=?0.008) and postprandial states (area under the curve (AUC), 10.8?±?1.9 to 23.4?±?4.1 pg?×?h/ml?×?103; P?=?0.006) but remained unchanged following IMM. BAs increased after RYGB (AUC ×103, 6.63?±?1.3 to 15.16?±?2.56 μM?×?h; P?=?0.003) and decreased after IMM (AUC ×103, 8.22?±?1.24 to 5.70?±?0.70; P?=?0.01). No changes were observed in the ratio of 12α-hydroxylated/non-12α-hyroxylated BAs. Following RYGB, FGF19 AUC correlated with BAs (r?=?0.54, P?=?0.04) and trended negatively with HbA1c (r?=??0.44; P?=?0.09); these associations were not observed after IMM.

Conclusions

BA and FGF19 levels increased after RYGB but not after IMM in subjects who achieved similar improvement in glycemic control. Further studies are necessary to determine whether these hormonal changes facilitate improved glucose homeostasis.
  相似文献   
29.
BACKGROUND: Gated single photon emission computed tomography (SPECT) with automated methods allows the quantitative assessment of left ventricular function and perfusion; however, its accuracy must be defined for patients with large earlier infarctions and severe rest perfusion defects, in whom the estimation of endocardial and epicardial borders might be more difficult, even with automated edge-detection techniques. METHODS AND RESULTS: We prospectively compared the automated measurements of left ventricular ejection fraction (LVEF) and volumes from rest-injected gated Technetium 99m (Tc99m) perfusion SPECT with equilibrium radionuclide angiocardiography (ERNA) in 62 patients and the assessment of regional function with echocardiography in 22 patients. Forty-six patients had an earlier myocardial infarction (mean defect size, 34% of left ventricle; SD, 12.7%; range, 8% to 56%); 27 patients had large defects (> or = 20% of left ventricle; LVEF range, 8% to 75%). LVEF, as determined with Cedars-Sinai software (quantitative gated SPECT), correlated well with ERNA (r = 0.941; y = 1.003x + 1.15; P<.0001; SE of the estimate = 6.3%; mean difference -1.3% for LVEF) in the entire study population and in the subgroups of patients with an earlier infarction, severe defects, and large infarctions (> or = 20% of the left ventricle). A correlation existed between gated SPECT and ERNA volumes (r = 0.882, y = 1.040x - 14.7, P<.0001 for end-diastolic volume; r = 0.954, y = 1.147x - 13.9, P<.0001 for end-systolic volumes with the count-ratio technique), but with wider limits of agreement. The exact segmental score agreement between gated SPECT and echocardiography for regional function was 79.8% (281 of 352, kappa = 0.682). CONCLUSIONS: Automated gated SPECT provides an accurate assessment of ejection fraction and regional function, even in the presence of an earlier myocardial infarction with large perfusion defects and significant left ventricular dysfunction.  相似文献   
30.
Chua KS  Kong KH 《Brain injury : [BI]》2005,19(12):1063-1066
Introduction: An unusual case of urinary retention is reported occurring during the inpatient rehabilitation of minimally responsive state (MRS) following severe traumatic brain injury (TBI). Clinical picture: Urodynamic evaluation showed detrusor acontractility and subsequent management involved intermittent bladder catheterization and treatment of a single urinary tract infection. Treatment: Factors contributing to her bladder paralysis included severe immobility, tetraplegia and treatment of diffuse spasticity with oral Dantrolene sodium 250 mg per day. Constipation, diabetes and spinal cord injury were absent. In addition, she received unilateral partial sciatic neurolysis with 50% alcohol for severe knee flexor spasticity and intra-muscular Botulinum toxin A to both spastic upper limbs. Outcome: Bladder acontractility resolved completely when Dantrolene was reduced with subsequent achievement of a catheter-free status and small post-void residual volumes. Repeat urodynamics showed spontaneous detrusor contractions. Conclusion: A discussion of possible aetiologic factors for detrusor acontracility following TBI is presented including a brief review of the literature.  相似文献   
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