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OBJECTIVES: Both benign prostatic hyperplasia and lower urinary tract symptoms (LUTS) have been shown to increase with age in men, but a causal relationship between prostate volume and symptoms has not been established. This study had two aims, to investigate the inter-relationships of age, symptoms, and various zonal measurements in the prostate and to assess the impact of heritable influences on symptom score. METHODS: Eighty-three monozygotic twin pairs and 83 dizygotic twin pairs were studied to determine age and LUTS as assessed by the American Urological Association symptom score. Their prostate volumes (total, transition zone, and peripheral zone) were measured by transrectal ultrasound. RESULTS: There was significant evidence of pairwise correlation between transition zone and symptom score (P = 0.04) and between age and symptom score (P = 0.03). Age also showed significant correlation with all volume measurements. Heritability appears to account for 82.6% of the variability in symptom score in men older than 50 years. CONCLUSIONS: This study provides evidence that age and transition zone volume play a role in LUTS, but also that their influence is not strong. Estimates of heritability suggest that hereditary factors contribute substantially to LUTS.  相似文献   
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A prospective study of 50 adults treated with fusion, realignment, and segmental spinal instrumentation for spinal deformity was conducted to assess the safety, accuracy, and efficacy of the free-hand pedicle screw placement technique. Postoperative computed tomographic scans were performed to evaluate the placement of 282 screws and were correlated with patients' clinical outcomes. Five screws were placed at T12, 26 at L1, 39 at L2, 48 at L3, 73 at L4, 35 at L5, and 50 at S1. Nine screws (3%) were misplaced and included three screws (1.06%) that violated the medial wall with no clinical sequelae or revision surgery needed. There were no neurologic deficits related to screw placement. The free-hand technique is a safe and cost-effective method for pedicular screw placement during surgery for adult spine deformities.  相似文献   
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The elimination, disposition and protein binding of ibuprofen (IBU) in premature infants were studied for use in the prevention of intraventricular hemorrhage and closure of patent ductus arteriosus. The kinetic profile of i.v. IBU lysine (10 mg/kg bolus) given within the first 3 h after birth was studied in 21 premature neonates (mean birthweight = 944.7 g, range: 575–1450 g; gestational age: 26.8 weeks, range: 22–31 weeks). Blood samples (0.3 ml/sample) were obtained at time 0 and at 1, 3, 6, 12, 24, 48, and 72 h post-dose for IBU by high-performance liquid chromatography (HPLC). Kinetic analyses assumed applicability of one open-compartment model and calculations from the model-independent areas under the time concentration curve (AUC). Data (mean ± SEM) show that apparent volume of distribution (AVd) was 62.1 ± 3.9 ml/kg, plasma t 1/2 beta was 30.5 ± 4.2 h, elimination rate constant (kel) was 0.032 ± 0.004 h-1plasma clearance was 2.06 ± 0.33 ml/kg/h and plasma concentration (Cp) at 1 h was 180.6 ±11.1 mg/1. Gestational age and birthweight were not related to drug elimination. In 10 neonates, IBU maintenance dose of 5 mg/kg once daily on days 2 and 3 generated mean Cp of 116.6 ± 54.5 mg/1 and 113.6 ± 58.2mg/1, respectively. Protein binding by ultrafiltration and capillary electrophoresis showed that the percentage bound IBU was significantly lower in full term cord plasma (94.98 ± 0.39%, n = 26) compared to adult plasma protein (mean ± SE = 98.73 ± 0.31%, n = 8, p < 0.0001). Compared to data from adults and older children, IBU elimination is markedly prolonged in neonates and protein binding is slightly lower. Thus, investigational and clinical therapeutic regimens should be adjusted to account for decreased drug disposition to ensure safe and effective therapy.  相似文献   
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Pulmonary alveolar proteinosis represents a rare syndrome characterized by the accumulation of proteinaceous phospholipid-laden material in the alveoli. This leads to impaired gas exchange and arterial hypoxemia of varying degrees. The diagnosis is confirmed by lung biopsy. Sequential whole-lung lavage (WLL) first described in 1963 is the standard of care. We report a case of a male diagnosed of having pulmonary alveolar proteinosis (PAP) on transbroncial lung biopsy (TBLB). He was treated with sequential WLL (Left followed by right, Left being more involved on chest X-ray) followed by recombinant GM-CSF, with good result.  相似文献   
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Traumatic palsy of the descending branch of the posterior interosseous nerve (PIN) is rare. Traumatic palsy usually involves the entire PIN around the elbow, leading to finger drop with loss of extension of all fingers and thumb. In the literature, to the best of our knowledge, only one case of traumatic palsy of the descending branch of the PIN due to penetrating injury is reported [1]. We report a neglected, rare case with complete loss of thumb extension and weakness in index finger extension following penetrating injury to the forearm. Our report shows that to diagnose the lesion site in partial PIN palsy, detailed knowledge of the PIN branching pattern is necessary.  相似文献   
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