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排序方式: 共有602条查询结果,搜索用时 15 毫秒
31.
CALLA-positive myeloma: an aggressive subtype with poor survival 总被引:5,自引:0,他引:5
Detailed immunotyping was carried out on 21 direct myeloma bone marrow aspirates and eight human myeloma cell lines. Four previously untreated common acute lymphoblastic leukemia antigen (CALLA)-positive myeloma patients were identified and six of eight cell lines (75%) were also positive. CALLA positivity, as part of an immature B phenotype, was found to correlate with very aggressive clinical disease: median survival six months v 56 months for the CALLA-negative group. 相似文献
32.
Anniek KD Visser Nisha K Ramakrishnan Antoon TM Willemsen Valentina Di Gialleonardo Erik FJ de Vries Ido P Kema Rudi AJO Dierckx Aren van Waarde 《Journal of cerebral blood flow and metabolism》2014,34(1):118-125
The PET tracer [11C]5-hydroxytryptophan ([11C]5-HTP), which is converted to [11C]5-hydroxytryptamine ([11C]5-HT) by aromatic amino acid decarboxylase (AADC), is thought to measure 5-HT synthesis rates. But can we measure these synthesis rates by kinetic modeling of [11C]5-HTP in rat? Male rats were scanned with [11C]5-HTP (60 minutes) after different treatments. Scans included arterial blood sampling and metabolite analysis. 5-HT synthesis rates were calculated by a two-tissue compartment model (2TCM) with irreversible tracer trapping or Patlak analysis. Carbidopa (inhibitor peripheral AADC) dose-dependently increased [11C]5-HTP brain uptake, but did not influence 2TCM parameters. Therefore, 10 mg/kg carbidopa was applied in all subsequent study groups. These groups included treatment with NSD 1015 (general AADC inhibitor) or p-chlorophenylalanine (PCPA, inhibitor of tryptophan hydroxylase, TPH). In addition, the effect of a low-tryptophan (Trp) diet was investigated. NSD 1015 or Trp depletion did not affect any model parameters, but PCPA reduced [11C]5-HTP uptake, and the k3. This was unexpected as NSD 1015 directly inhibits the enzyme converting [11C]5-HTP to [11C]5-HT, suggesting that trapping of radioactivity does not distinguish between parent tracer and its metabolites. As different results have been acquired in monkeys and humans, [11C]5-HTP-PET may be suitable for measuring 5-HT synthesis in primates, but not in rodents. 相似文献
33.
34.
R Wanitphakdeedecha TH Nguyen TM Chen 《Journal of the European Academy of Dermatology and Venereology》2010,24(4):445-448
Background Appropriate pricing for medical services of not‐for‐profit hospital is necessary. The prices should be fair to the public and should be high enough to cover the operative costs of the organization. Objective The purpose of this study was to determine the cost and unit cost of medical services performed at the Mohs and Dermasurgery Unit (MDU), Department of Dermatology, The University of Texas – MD Anderson Cancer Center, Houston, TX from the healthcare provider’s perspective. Methods MDU costs were retrieved from the Financial Department for fiscal year 2006. The patients’ statistics were acquired from medical records for the same period. Unit cost calculation was based on the official method of hospital accounting. Results The overall unit cost for each patient visit was $673.99 United States dollar (USD). The detailed unit cost of nurse visit, new patient visit, follow‐up visit, consultation, Mohs and non‐Mohs procedure were, respectively, $368.27, $580.09, $477.82, $585.52, $1,086.12 and $858.23 USD. With respect to a Mohs visit, the unit cost per lesion and unit cost per stage were $867.89 and $242.30 USD respectively. Conclusions Results from this retrospective study provide information that may be used for pricing strategy and resource allocation by the administrative board of MDU. 相似文献
35.
H R Cohen J R Green W R Crombleholme 《International journal of gynaecology and obstetrics》1991,35(1):51-54
Pregnancy outcome of 83 patients with a positive urine toxicology screen for cocaine in the third trimester were reviewed. The outcomes of pregnancies complicated by cocaine abuse were compared to those of matched controls selected from our general obstetric population. We observed a statistically significant increase in the incidence of premature separation of the placenta, low birthweight infants, preterm deliveries, and the incidence of fetal distress requiring cesarean section. On admission, 55% of patients denied recent cocaine use. These observations have implications for planning perinatal services. 相似文献
36.
GL Marseglia S Savasta A Ravelli TM Gaino GR Burgio 《Acta paediatrica (Oslo, Norway : 1992)》1995,84(9):1086-1088
We report the case of a 9-year-old boy with a spinal cord meningioma whose only manifestations were recurrent episodes of chest pain lasting for 2 years. This case shows that spinal cord meningioma should be considered among the possible causative factors of chronic chest pain in childhood. Chest pain, meningioma, spinal tumors 相似文献
37.
Howard Minkoff Amos N. Grunebaum Richard H. Schwarz Joseph Feldman Marinella Cummings William Crombleholme Lorraine Clark George Pringle William M. McCormack 《American journal of obstetrics and gynecology》1984,150(8):965-972
Prematurity remains a major cause of perinatal mortality in the United States. Some research has indicated that infectious agents play a role in either initiating preterm labor, causing premature rupture of the membranes, or preventing tocolysis. This study attempted to determine if the presence of various vaginal pathogens in early pregnancy was associated with the subsequent development of premature rupture of membranes or preterm labor. We found that among 233 evaluable patients those with Trichomonas vaninalis were significantly more likely to have premature rupture of the membranes (p < 0.03), and those with Bacteroides sp. were more likely to be delivered of their infants before 37 weeks (p < 0.03) and to have infants weighing less than 2500 gm (p < 0.05). Those with Ureaplasma urealyticum more frequently began preterm labor (p < 0.05). Preterm premature rupture of the membranes was found significantly more often among patients with Bacteroides sp. Stepwise multiple logistic regression analysis indicated that those associations were not related to the number of previous abortions, deliveries, or preterm deliveries or to maternal age. We conclude that microbiologic screening in early pregnancy may aid in the assessment of patient risk for preterm delivery. 相似文献
38.
Bouchard S Johnson MP Flake AW Howell LJ Myers LB Adzick NS Crombleholme TM 《Journal of pediatric surgery》2002,37(3):418-426
Background: The EXIT (ex utero intrapartum treatment) procedure, although initially designed for reversal of tracheal occlusion in fetuses with congenital diaphragmatic hernias (CDH), has been adapted to treat a variety of fetal conditions. Methods: A retrospective chart review of all consecutive EXIT procedures since 1996 was conducted. Results: Thirty-one women underwent the EXIT procedure, with an average maternal age of 29 years (range, 20 to 38), and average gestational age of 34 weeks (range, 29 to 40). The indication was airway obstruction from fetal neck mass in 13, and reversal of tracheal occlusion from in utero clipping in 13. Singular indications included an EXIT-to-ECMO (extracorporeal membrane oxygenation) procedure for a fetus with CDH and a cardiac defect (n = 1), congenital high airway obstruction syndrome (CHAOS, n = 1), resection of a very large congenital cystic adenomatoid malformation of the lung (CCAM) on uteroplacental bypass (n = 1), unilateral pulmonary agenesis (n = 1), and thoracoomphalopagus conjoined twins. The mean duration on uteroplacental bypass (from uterine incision to umbilical cord clamping) was 30.3 [plusmn] 14.7 minutes (range, 8 to 66). No fetus experienced hemodynamic instability during uteroplacental bypass as recorded by fetal heart rate (FHR), pulse oximeter, and fetal echocardiography, except for one instance of reversible bradycardia from umbilical cord compression. The mean FHR and fetal saturation were 153.0 [plusmn] 38.5 beats per minute and 71.2% [plusmn] 19.9%, respectively. Five fetuses required a tracheostomy. Only 1 death occurred during an EXIT procedure because of inability to secure the airway secondary to extensive involvement by a lymphangioma. The average cord pH and pCO2 were, respectively, 7.20 [plusmn] 0.11 and 63.2 [plusmn] 14.6. Two maternal complications occurred: bleeding from a hysterotomy site and dehiscence of an old hysterotomy scar noticed at a subsequent cesarean section. The average maternal blood loss was 848.3 [plusmn] 574.1 mL. Conclusion: The EXIT procedure was used successfully to ensure uteroplacental gas exchange and fetal hemodynamic stability during a variety of surgical procedures performed to secure the fetal airway or ensure successful transition to postnatal environment. 相似文献
39.
Mackenzie TC Crombleholme TM Johnson MP Schnaufer L Flake AW Hedrick HL Howell LJ Adzick NS 《Journal of pediatric surgery》2002,37(3):303-309
Background/Purpose: Accurate prenatal diagnosis of complex anatomic connections and associated anomalies has only been possible recently with the use of ultrasonography, echocardiography, and fetal magnetic resonance imaging (MRI). To assess the impact of improved antenatal diagnosis in the management and outcome of conjoined twins, the authors reviewed their experience with 14 cases. Methods: A retrospective review of prenatally diagnosed conjoined twins referred to our institution from 1996 to present was conducted. Results: In 14 sets of conjoined twins, there were 10 thoracoomphalopagus, 2 dicephalus tribrachius dipus, 1 ischiopagus, and 1 ischioomphalopagus. The earliest age at diagnosis was 9 weeks' gestation (range, 9 to 29; mean, 20). Prenatal imaging with ultrasonography, echocardiography, and ultrafast fetal MRI accurately defined the shared anatomy in all cases. Associated anomalies included cardiac malformations (11 of 14), congenital diaphragmatic hernia (4 of 14), abdominal wall defects (2 of 14), and imperforate anus (2 of 14). Three sets of twins underwent therapeutic abortion, 1 set of twins died in utero, and 10 were delivered via cesarean section at a mean gestational age of 34 weeks. There were 5 individual survivors in the series after separation (18%). In one case, in which a twin with a normal heart perfused the cotwin with a rudimentary heart, the ex utero intrapartum treatment procedure (EXIT) was utilized because of concern that the normal twin would suffer immediate cardiac decompensation at birth. This EXIT-to-separation strategy allowed prompt control of the airway and circulation before clamping the umbilical cord and optimized control over a potentially emergent situation, leading to survival of the normal cotwin. In 2 sets of twins in which each twin had a normal heart, tissue expanders were inserted before separation. Conclusions: Advances in prenatal diagnosis allow detailed, accurate evaluations of conjoined twins. Careful prenatal studies may uncover cases in which emergent separation at birth is lifesaving. 相似文献
40.
Clinical evaluation of biomarkers in Gaucher disease 总被引:1,自引:0,他引:1
Novel or candidate biomarkers require thorough evaluation to establish their utility in a clinical setting. This paper describes an evaluation of several established enzyme markers of Gaucher disease and a newly-described chemokine, pulmonary and activation-regulated chemokine (PARC). The ability of the biomarkers to rank patients with Gaucher disease in order of disease severity and organ bulk, and to reflect changes in key clinical parameters in response to enzyme replacement therapy were evaluated. PARC concentrations were found to be reliably correlated with visceral disease and with key clinical responses to enzyme replacement in an unbiased manner. Unlike chitotriosidase and serum angiotensin-converting enzyme activity, genetic variation in serum PARC did not appear to influence its utility as a biomarker.
Conclusion: For each new candidate biomarker of lysosomal storage diseases, a similar clinical evaluation will be required, though the approach will need to be modified according to the clinical features and natural history of each disorder. 相似文献
Conclusion: For each new candidate biomarker of lysosomal storage diseases, a similar clinical evaluation will be required, though the approach will need to be modified according to the clinical features and natural history of each disorder. 相似文献