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21.
One hundred and twenty eight Brazilian children with lymphoblastic leukaemia were intensively treated with a Berlin-Frankfurt-Munich based protocol. More children had a white cell count above 50 x 10(9)/l (31%) then observed in developed countries. After a median follow up of 31 months (11-58 months), the estimated probability of relapse free survival was 41% (7%) for the whole group. After adjustment in the Cox's multivariate model, malnutrition was the most significant adverse factor affecting duration of complete remission. Age above 8 years and high peripheral white cell count were also significant adverse factors. Among the nutritional indices, the height for age and weight for age z scores were both significant, whether the cut off points of z-2 or z = -1.28 were chosen to define malnutrition. A strong statistical association between the two indices was found; the contribution of height for age z score to the prediction of relapse free survival was more significant. Children with height for age z score < -2 had a relapse risk of 8.2 (95% confidence interval 3.1 to 21.9) relative to children with z score > -2. The results of this study suggest that socioeconomic and nutritional factors should be considered in the prognostic evaluation of children with leukaemia in developing countries.  相似文献   
22.
Michael  AS; Mafee  MF; Valvassori  GE; Tan  WS 《Radiology》1985,154(2):413-419
A retrospective review of the dynamic CT studies performed in our institution on head and neck lesions, excluding the brain, was carried out. Five basic types of density vs. time curves were obtained. Dynamic CT scanning is valuable in the differential diagnosis, management, and followup of such cases; its usefulness as an imaging modality in diagnosis and followup of hemangiomas is stressed.  相似文献   
23.
Dhar NB  Grundfest S  Jones JS  Streem SB 《The Journal of urology》2005,174(5):1844-6; discussion 1846
PURPOSE: While the effect of jejunoileal bypass (JIB) reversal has been well studied regarding hepatic function, there is little information regarding the effect of reversal on renal function and even less data regarding the metabolic urinary stone environment. We evaluated the results of JIB reversal on renal function, the urinary stone milieu and the clinical development of recurrent calculi in affected patients. MATERIALS AND METHODS: From 1995 to 2003, 4 female patients with a mean age of 48.2 years underwent JIB reversal primarily for refractory stone disease. The clinical and metabolic courses prior to and following bypass reversal were reviewed specifically to evaluate renal function, serum and urinary metabolic stone profiles, and clinical stone formation. RESULTS: At initial presentation following JIB all 4 patients had significantly increased 24-hour urinary oxalate (range 80 to 160 mg, mean 112.5, normal less than 50) and significantly low 24-hour urinary citrate (range 5 to 62 mg, mean 21.5, normal greater than 320). Following reversal 24-hour urinary oxalate normalized to between 31 and 36 mg (mean 33.75). However, 24-hour urinary citrate continued to be low (range 215 to 248 mg, mean 226.5). After JIB reversal all 4 patients continued to have new stones until the commencement of urinary alkalization, following which only 1 had 1 calculus, which occurred 47 months after reversal. After JIB mean serum creatinine was 1.48 mg/dl (range 0.8 to 1.9) and mean urinary creatinine excretion was 0.91 mg per hour (range 0.69 to 1.15). After JIB reversal mean serum creatinine was 1.28 mg/dl (range 0.6 to 2.0) and mean urinary creatinine excretion was 1.0 mg per hour (range 0.85 to 1.10). CONCLUSIONS: JIB reversal normalizes 24-hour urinary oxalate. While urinary citrate improves, it continues to be low and such patients are at high risk for recurrent stone formation. However, in this setting appropriate replacement therapy has a significant and positive impact on that propensity.  相似文献   
24.
BACKGROUND AND OBJECTIVE: The effect of the excimer laser (308 nm) parameters on transmyocardial revascularization (TMR) channels is not well defined. This study investigates the influence of the pulse repetition rate, the size of the delivery catheter and its advancement speed on the morphology of TMR channels in vivo. STUDY DESIGN/MATERIALS AND METHODS: Myocardial ablation was performed in a porcine model (N = 27) using multifiber catheters of 1.0 and 1.4 mm in diameter. The catheters were advanced into the myocardium at different speeds (1.27 and 2.54 mm/sec) while ablating at various repetition rates (10-80 Hz). The radiant exposure was kept at 35 mJ/mm(2) throughout the experiments. The channel histology was quantified by digital microscopy. RESULTS: The channel cross-sectional area and the extent of the thermal damage decrease as the catheter advancement speed exceeds the ablation speed and vice versa. Within the parameters tested, advancement speed of about 1.3 mm/sec and pulse repetition rates of 40 Hz produce channels of size comparable to the catheter's diameter with moderate thermomechanical damage. CONCLUSIONS: The repetition rate, catheter size, and catheter advancement speed are closely intertwined and crucial to the histological outcome of excimer laser based TMR.  相似文献   
25.
Spectral imaging permits two-dimensional mapping of the backscattering properties of biological systems. Such mapping requires broadband illumination of the entire area of interest. However, imaging of turbid biological media under these conditions often involves mean photon path lengths that exceed the pixel size. Using a numerical Monte Carlo model, we have studied the effects of photon scattering in a hemoglobin-bearing model system. We find that photon migration and the resulting wavelength-dependent optical coupling between pixels can complicate the analysis of imaging spectroscopy data. In fact, the wavelength dependence of photon trajectories also alters the distribution of photon exit angles at the tissue surface. We therefore find that the finite optical field of view of an imaging spectrometer can affect the measured spectra in the absence of chromatic aberrations.  相似文献   
26.

BACKGROUND:

Psychosocial stress can be the cause or the consequence of hypertension.

OBJECTIVE:

To study the association between hypertension and anxiety or depression in adults from Hong Kong, China.

SUBJECTS AND METHODS:

Patients with diagnosed hypertension (n=197) were recruited to complete the Hospital Anxiety and Depression Scale (HADS) questionnaire. The control group comprised 182 normotensive subjects recruited using random telephone numbers.

RESULTS:

The score in the anxiety subscale (HADS-A) of the HADS correlated with age (r= −0.23, P<0.001) and sex (r=0.11, P=0.042), and was found to be higher in women. The score in the depression subscale (HADS-D) correlated with age (r=0.17, P=0.003) and hypertension (r=0.12, P=0.039), but not with sex (r=0.02, P=0.68). When the control subjects were matched for sex and age with the subjects with hypertension, the mean HADS-A score was 5.51±0.41 in 113 hypertensive subjects and 4.38±0.39 in 113 normotensive subjects (P=0.047). The mean HADS-D score was 5.56±0.39 in the hypertensive and 4.76±0.32 in the normotensive subjects (P=0.11). Multiple regression analysis using data from both groups indicated that the HADS-A score was related to the HADS-D score (β=0.49, P<0.001), age (β= −0.25, P<0.001) and sex (β=0.12, P=0.01) (R2=0.28), whereas the HADS-D score was related to the HADS-A score (β=0.48, P<0.001), age (β=0.30, P<0.001), positive smoking status (β=0.13, P=0.004) and lack of exercise habit (β=0.12, P=0.008) (R2=0.31). Hypertension was related to waist circumference, history of parental hypertension and age (R2=0.38, P<0.001). Anxiety and depression scores were rejected as independent variables.

CONCLUSIONS:

Hypertension was associated with anxiety but not depression; however, age, history of parental hypertension and central obesity appeared to have a stronger association with hypertension in adults from Hong Kong.  相似文献   
27.
QUADAS的制定:用于系统评价中评价诊断性研究质量的工具   总被引:5,自引:0,他引:5  
背景在以系统评价为基石的循证医学时代,需要有恰当的质量评价工具。对诊断性研究的评价目前尚缺乏系统开发且经过验证的评价工具。本研究的目的是采用共识决策法整合经验证据和专家意见,制定在系统评价时用于评价原始诊断性研究质量的工具。方法按照循证原则,我们在之前发表的3篇诊断性研究文献的综述的基础上,初选出一些条目形成列表,然后通过Delphi流程逐步调整列表,形成质量评价工具。参与Delphi流程的都是诊断性研究领域的专家。结果共有9位诊断学领域的专家参与Delphi流程。经过4轮Delphi流程后,专家们对哪些条目应纳入评价工具达成共识,我们把这个评价工具命名为QUADAS。纳入条目从最初的28个减少到14个,涵盖了疾病谱、金标准、疾病进展偏倚(disease progression bias)、证实偏倚(verification bias)、评价偏倚、临床评价偏倚、合并偏倚、试验的实施、病例退出以及不确定结果。QUADAS工具中的每个条目都配有评分细则。结论本研究项目开发出了用于诊断性试验系统评价的循证质量评价工具。下一步工作是确定其适用性和有效性。  相似文献   
28.
QUADAS评价:一种用于诊断性研究的质量评价工具(修订版)   总被引:2,自引:0,他引:2  
背景 QUADAS是一种新近发展起来的诊断性研究的质量评价工具。虽然已有系统评价采用了QUADAS,但尚未得以正式确证。本研究的目的是评价QUADAS的有效性和实用性。方法3位评价者采用QUADAS独立评价30项研究的质量。比较每位评价者的评分与最终结论之间的意见一致度。这主要是通过比较所有QUADAS条目的总分和每个单项的得分来实现的。20位曾在其系统评价中使用过QUADAS的评价者就其使用经验完成一份简短的问卷。结果就所有条目而言,每位评价者的评分与最终结论之间的意见一致度分别达到了91%、90%和85%。就单项QUADAS条目而言,一致度在50%至100%之间,中位值是90%。与难以解释的试验结果和退出病例相关的条目,评分结果差异最大。有关QUADAS内容的反馈意见普遍较好,仅少数评价者提出了有关QUADAS涵盖面、使用便利性、评分说明的清晰度及有效性方面的问题。结论QUADAS内容本身无需作大的修改。评价过程的主要困难出现在难以解释的试验结果和退出病例这2个条目的评分上。对这些条目的评分指南提出了修改意见。评价者必需根据其系统评价制定相应的评分指南,并确保所有评价者都清楚如何评分。评价者还应考虑是否所有的QUADAS条目都与其系统评价相关,以及其他质量条目是否应作为其系统评价的评价部分。  相似文献   
29.

Objectives/Hypothesis.

To determine whether respiratory compromise from bilateral vocal fold impairment (paralysis) can be objectively alleviated by reinnervation and pacing.

Methods.

A patient with paramedian vocal folds and synkinesis had a tracheotomy for stridor after bilateral laryngeal nerve injury and Miller Fisher syndrome. One posterior cricoarytenoideus (PCA) received a nerve‐muscle pedicle fitted with a perineural electrode for pacemaker stimulation. The airway was evaluated endoscopically and by spirometry for up to 1 year.

Results.

Bilateral vocal fold patency during quiet breathing was reversed to active vocal fold adduction during tracheal occlusion. Peak inspiratory flows (PIFs) were significantly higher (P < .001) after reinnervation. PIFs and glottic apertures increased further under stimulation (42 Hz, 1–4 mA, 42–400 μsec). although the differences were not significant.

Conclusions.

Based on our preliminary data, PCA reinnervation and pacing offer promise for amelioration of respiratory compromise after paradoxical adduction in bilateral vocal fold impairment. Laryngoscope, 2010  相似文献   
30.
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