人工膝关节单髁置换术36例临床应用特点:1年随访影像学及膝关节功能评估

目的:现代人工膝关节单髁置换术具有创伤小、并发症少、保留骨量、容易翻修、关节功能恢复快等优点,但其远期临床应用效果有待证实。总结人工膝关节单髁置换术治疗膝关节单间室疾病的特点及疗效,并随访全部患者术后1年以上影像学表现及膝关节功能评分。方法:选择2001-03/2006-03在解放军总医院关节置换中心治疗的36例膝关节骨性关节炎病例,均施行了现代膝关节单髁置换术。男性8例,女性28例,年龄52～71岁,体质量56～80kg,均为内侧胫股间室置换。采用国际上评价膝关节功能常用的HSS评分评定疗效,并对全部病例的适应证、手术方法、临床和影像学表现进行随访和总结。结果:①36例患者全部得到随访,随访时间为12～72个月,平均31.5个月。②术后切口无感染、无下肢血栓、骨折等并发症。③末次随访时,HSS评分由术前65分提高至94.5分,优29膝(80%),良7膝(20%),平均关节活动范围120°(110°～135°)。④影像学检查所有假体无位置不良,无松动与假体周围骨溶解的迹象,未观察到对侧间室与髌股关节间室有进行性退变。结论:经随访膝关节功能及影像学评估证实现代人工膝关节单髁置换术是治疗膝关节单间室骨性关节炎的有效方法。     

AS-1 red cells for neonatal transfusions: a randomized trial assessing donor exposure and safety

BACKGROUND: Despite recent optimism about the use of erythropoietin therapy to treat the anemia of prematurity, very-low-birth-weight infants who are severely ill receive multiple red cell (RBC) transfusions. Many physicians transfuse relatively fresh RBCs to newborn infants, exposing them to multiple donors and possibly increasing their risk of acquiring transfusion-transmitted infections. STUDY DESIGN AND METHODS: A randomized, single-blind clinical trial was conducted to determine, as the primary endpoint, whether RBCs collected from one dedicated donor and stored for < or = 42 days in AS-1 storage media could safely supply all small-volume RBC transfusions (15 mL/kg/dose) needed by very-low-birth-weight infants (0.6-1.3 kg) during the first 84 days of life. Secondary endpoints were the assessment of the possible adverse clinical and biochemical effects of transfusing AS- 1 RBCs stored for < or = 42 days. Control infants received identical nursery care, except they received fresh RBCs stored < or = 7 days in CPDA-1. RESULTS: Infants transfused with AS-1 RBCs were exposed to a mean of 1.6 donors,-compared with an exposure to 3.7 donors for infants given CPDA-1 RBCs (p < 0.05). Neither clinical transfusion reactions nor the results of multiple laboratory tests were significantly different in infants who received slow transfusions (15 mL/kg) of AS-1 RBCs stored for < or = 42 days and in infants who received the same volume of CPDA-1 RBCs stored < or = 7 days. CONCLUSION: AS-1 RBCs, usually from only one dedicated donor, can safely supply all RBCs needed by most very-low-birth-weight infants-a practice that decreases donor exposure and likely increases transfusion safety.     

DO CLINICIANS PRESCRIBE HRT FOR HYPERTENSIVE POSTMENOPAUSAL WOMEN?

SUMMARY Despite the benefits of hormone replacement therapy (HRT) in relieving menopausal symptoms, there continues to be anxiety about its use in women who also have hypertension. To examine clinical practice in relation to HRT, especially in patients with hypertension, and to canvass opinions on potential or perceived side-effects, the authors conducted a postal survey of HRT prescribing habits among 285 GPs, physicians and obstetricians in the West Midlands. The overall response rate to the questionnaire was 191 (66.3%): 61 clinicians reported that they would not prescribe HRT in women whose hypertension was difficult to control, but only 3 would withhold treatment if blood pressure was well controlled; 9% of physicians and 13% of gynaecologists did not routinely measure blood pressure before starting HRT or monitor BP at follow-up (24% and 10% respectively). A proportion of GPs (20%), physicians (21%) and gynaecologists (9%) reported that in their opinion HRT raised blood pressure, and a minority in each group considered that HRT increased the risk of venous thrombosis, stroke and myocardial infarction. This study demonstrates differences among GPs, physicians and gynaecologists in the use of HRT in menopausal women with hypertension, the authors suggest that, in view of data from studies of the effects of HRT on blood pressure and the possible reduction of cardiovascular disease, these clinicians can be reassured and hypertensive women need not be denied the benefits of HRT, as long as there is careful monitoring.     

Effect of diltiazem and a prostaglandin derivative (PGBx) on platelet function during long-term storage

Calcium is an intermediate messenger between platelet stimuli and platelet response. Published studies have shown that the decreased ability of platelets to control calcium flux during long-term storage leads to platelet senility. Platelet metabolism might be more efficient during storage if pharmacologic agents that limit calcium movement were incorporated into the platelet concentrate storage solution. This hypothesis was tested by storing platelets with the calcium channel blocker, diltiazem, or with a prostaglandin B1 derivative, PGBx. During a 15-day storage period, platelets incubated with either diltiazem or PGBx showed improved function, as measured by aggregation, as compared to control platelets. The PGBx -enhanced platelet function during storage was accompanied by a significant decrease in glucose and an increase in adenosine triphospate concentrations. Platelet function after storage with PGBx improved in spite of significantly lower pH levels of the platelet concentrates at all time points tested. These studies suggest that the maintenance of calcium ion homeostasis during long-term platelet storage is important to in vitro platelet function even if the Ca2+ balance is maintained at the expense of pH and the glucose concentrations.     

Bone mineral accrual in 4‐ to 10‐year‐old precompetitive,recreational gymnasts: A 4‐year longitudinal study

Competitive female gymnasts have greater bone mineral measures than nongymnasts. However, less is known about the effect of recreational and/or precompetitive gymnastics participation on bone development. The purpose of this study was to investigate whether the differences previously reported in the skeleton of competitive female gymnasts are also demonstrated in young children with a current or past participation history in recreational or precompetitive gymnastics. One hundred and sixty‐three children (30 gymnasts, 61 ex‐gymnasts, and 72 nongymnasts) between 4 and 6 years of age were recruited and measured annually for 4 years (not all participants were measured at every occasion). Total‐body (TB), lumbar spine (LS), and femoral neck (FN) bone mineral content (BMC) were measured by dual‐energy X‐ray absorptiometry (DXA). Multilevel random‐effects models were constructed and used to predict differences in TB, LS, and FN BMC between groups while controlling for differences in body size, physical activity, and diet. Gymnasts had 3% more TB and 7% more FN BMC than children participating in other recreational sports at year 4 (p < .05). No differences were found at the LS between groups, and there were no differences between ex‐gymnasts' and nongymnasts' bone parameters (p > .05). These findings suggest that recreational and precompetitive gymnastics participation is associated with greater BMC. This is important because beginner gymnastics skills are attainable by most children and do not require a high level of training. Low‐level gymnastics skills can be implemented easily into school physical education programs, potentially affecting skeletal health. © 2011 American Society for Bone and Mineral Research.     

双心室起搏与右心室起搏对充血性心力衰竭急性心功能的影响

目的最近研究提示心脏再同步治疗有效地改善了慢性心肌病心力衰竭患者心功能。本研究旨在探讨双心室和右心室起搏对心功能的相对影响。方法 15例慢性心力衰竭患者心功能Ⅲ级,左心室射血分数〈35%,QRS〉130ms和二尖瓣反流。安装心房-双心室再同步起搏器。彩色多普勒超声心动图观察心功能变化。结果急性双心室和右心室起搏并未影响左心室内径和短轴缩短率,也不影响左心室射血速度和排血量。左心室压力上升和下降峰速率无明显变化。等容收缩时间缩短（P〈0.05）,但不影响等容舒张时间。增加Z比例（P〈0.05）。缩短二尖瓣反流时间（P〈0.05）,对二尖瓣环和三尖瓣环运动幅度和峰速率无明显影响。双心室和右心室起搏之间无明显差别。结论双心室起搏改善了慢性心肌病心功能。双心室和右心室起搏无明显差别。双心室起搏是一种有前途的心脏再同步治疗方法。