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21.
Prader–Willi syndrome and Angelman syndrome are associated with parent-of-origin-specific abnormalities of chromosome 15q11–q13, most frequently a deletion of an ~4-Mb region. Because of genomic imprinting, paternal deficiency of this region leads to PWS and maternal deficiency to AS. Additionally, this region is frequently involved in other chromosomal rearrangements including duplications, triplications, or supernumerary marker formation. A detailed physical map of this region is important for elucidating the genes and mechanisms involved in genomic imprinting, as well as for understanding the mechanism of recurrent chromosomal rearrangments. An initial YAC contig extended from D15S18 to D15S12 and was comprised of 23 YACs and 21 STSs providing an average resolution of about one STS per 200 kb. To close two gaps in this contig, YAC screening was performed using two STSs that flank the gap between D15S18 and 254B5R and three STSs located distal to the GABRA5–149A9L gap. Additionally, we developed 11 new STSs, including seven polymorphic markers. Although several groups have developed whole-genome genetic and radiation hybrid maps, the depth of coverage for 15q11–q13 has been somewhat limited and discrepancies in marker order exist between the maps. To resolve the inconsistencies and to provide a more detailed map order of STSs in this region, we have constructed an integrated YAC STS-based physical map of chromosome 15q11–q13 containing 118 YACs and 118 STSs, including 38 STRs and 49 genes/ESTs. Using an estimate of 4 Mb for the size of this region, the map provides an average STS spacing of 35 kb. This map provides a valuable resource for identification of disease genes localized to this region as well as a framework for complete DNA sequencing.  相似文献   
22.
Summary The pathogenesis of rat virus (RV) infection was studied in random-bred Sprague-Dawley rats after oronasal inoculation of a recent RV isolate designated RV-Yale (RV-Y). RV-Y was pathogenic for rats inoculated as infants (2 days) whereas rats inoculated as juveniles (4 weeks) had asymptomatic infection and no lesions. Rats inoculated as infants developed pantropic infection accompanied by hepatic necrosis, granuloprival cerebellar hypoplasia and hemorrhagic encephalopathy. Virological and serological studies showed that virus could persist in inoculated rats for at least 35 days and for at least 28 days after seroconversion was first detected. Immuno-histochemical results indicated that RV-Y infects tissues conducive to virus excretion including kidney and lung. RV-Y also was found in genital tissues of some rats. Athymic juvenile rats inoculated intraperitoneally with RV-Y had a poor humoral immune response and harbored infectious virus for at least 3 weeks, whereas infection in euthymic control rats was detected for 1 week. These studies indicate that RV-Y can persists in the presence of humoral immunity and suggest that transmission of infection could occur for a substantial period after seroconversion. They also suggest that immunodeficient rats have increased susceptibility to persistent infection.  相似文献   
23.
The effect of mammalian insulin was studied in a freshwater fish, Clarias batrachus, at both high and low ambient temperatures. The hormone produced a significant but delayed, yet recoverable, lowering of blood glucose, a concurrent decrease in liver glycogen, and an increase in the glycogen content of muscles. The decrease in brain glycogen occurred during advanced hypoglycemia. Hypoglycemic seizures developed intermittently in most of the fishes whose plasma glucose and brain glycogen levels had been considerably depleted. Necrobiotic changes in the pancreatic islets, including degranulation and atrophy, and necrosis of B cells, were seen in the treated fish. In some cases damage to A cells and the acinar tissue was also observed. With the restitution of normal glucose and glycogen values, the islet cells also seemed to have recuperated. Changes in glycemia, glycogen, and the islets were more pronounced in the fishes held at 24 degrees C than in those at 10 degrees C, indicating that the ambient temperature plays an important role in blood glucose homeostasis as well as insulin.  相似文献   
24.
Bitolterol mesylate, 1.0 mg, or isoproterenol hydrochloride, 1.5 mg, was administered three times daily for 3 months in a double-blind, multicenter study via closed-port, intermittent-flow, compressor-driven nebulizer system (CPIF) to 182 nonsteroid-using patients with asthma. Mean baseline FEV1 was approximately 60% of predicted normal for both groups. Pulmonary function tests and vital signs were measured before and for up to 8 hours after treatments on test days 1, 30, 60, and 90. Mean maximum increases in FEV1 were 51%, 54%, 52%, and 55% for bitolterol versus 48%, 46%, 50%, and 43% for isoproterenol on these monthly test days. The mean FEV1 response remained greater than 15% over zero time (baseline) for greater than or equal to 8 hours after medication with bitolterol on each of four monthly pulmonary function test days and 2 1/2 to 5 hours for isoproterenol. Median durations of bronchodilator activity for bitolterol were 7.3, 6.5, 6.5, and 6.0 hours versus 4.0, 1.7, 3.7, and 1.9 hours for isoproterenol on the monthly test days. On these test days, 37% to 49% of the patients treated with bitolterol had a duration of action of at least 8 hours compared with 16% to 29% after isoproterenol treatment. The onset of activity was within 5 minutes for both drugs. Bitolterol provided superior bronchodilator activity with fewer adverse effects compared with isoproterenol, and there was no evidence for drug tolerance during this 3-month study.  相似文献   
25.
The primary standard of low air kerma rate sources or beams, maintained at the Radiological Standards Laboratory (RSL) of the Bhabha Atomic Research Centre (BARC), is a 60 cm3 spherical graphite ionization chamber. A 192Ir HDR source was standardized at the hospital site in units of air kerma strength (AKS) using this primary standard. A 400 cm3 bakelite chamber, functioning as a reference standard at the RSL for a long period, at low air kerma rates (compared to external beam dose rates), was calibrated against the primary standard. It was seen that the primary standard and the reference standard, both being of low Z, showed roughly the same scatter response and yielded the same calibration factor for the 400 cm3 reference chamber, with or without room scatter. However, any likelihood of change in the reference chamber calibration factor would necessitate the re-transport of the primary standard to the hospital site for re-calibration. Frequent transport of the primary standard can affect the long-term stability of the primary standard, due to its movement or other extraneous causes. The calibration of the reference standard against the primary standard at the RSL, for an industrial type 192Ir source maintained at the laboratory, showed excellent agreement with the hospital calibration, making it possible to check the reference chamber calibration at RSL itself. Further calibration procedures have been developed to offer traceable calibration of the hospital well ionization chambers.  相似文献   
26.
Background: Hand fractures and dislocations are common injuries in the pediatric population. This study aims to characterize the pediatric hand injuries that required closed reduction and identify those that required multiple reduction attempts. Methods: A retrospective cohort study was carried out in patients younger than 18 years of age with hand fractures or dislocations who underwent closed reduction in the emergency department (ED). Patients who ultimately required surgical reduction and fixation were not included. Results: Of the 310 hand injuries identified, 148 (114 fractures and 34 dislocations) underwent closed reduction in the ED; 7.4% of those required repeat reduction. Hand injuries that most often required repeat reduction included metacarpophalangeal joint dislocations (20.0%) and proximal phalanx neck (16.7%), metacarpal shaft (15.4%), metacarpal neck (6.2%), and proximal phalanx base (5.6%) fractures. No modifiable risk factors predicting the need for repeat reduction were identified. Conclusions: Some pediatric hand injuries are more likely to require repeat closed reduction by a hand surgeon. This retrospective study is the first step toward quality improvement as it provides opportunities for further research into the factors contributing to reductions that are unsuccessful at the first attempt. Identification of these factors and implementation of quality improvement measures are necessary to ensure the effective treatment of all pediatric hand injuries.  相似文献   
27.
Angiolymphoid hyperplasia with eosinophilia (ALHE) is a benign condition characterized by subcutaneous lesions in the head-neck region. It is frequently misdiagnosed as a malignant lesion. Knowledge of the existence of the disease and pathological interpretation are requisites for early diagnosis. We present a case report and review of the literature.  相似文献   
28.
Previous studies on oxygen consumption ( ) during weaning from mechanical ventilation assumed that an increase in ( ) reflected oxygen consumption by respiratory muscles ( ), and proposed as a weaning predictor. We measured CO2 production ( ) and plasma catecholamines in 20 short-term ventilated patients during weaning by SIMV and CPAP. as a percentage of during spontaneous ventilation ( %) ranged from 4.8% to 41.5%. also increased and correlated with . Plasma adrenaline and noradrenaline increased significantly to levels known to produce considerable increases in metabolic rate. Mean arterial pressure and heart rate concomitantly increased, but spontaneous minute ventilation decreased. Thus, since the increased plasma catecholamines are calorigenic, the assumption that represents is incorrect. Although mean % of successfully weaned patients was significantly less than that of failure-to-wean patients, the wide scatter of individual values in the latter group excludes % as an accurate weaning predictor.  相似文献   
29.
Management of Head and Neck Cancers poses a challenge inspite of several advances because of poor success in terms of response rate, survival and reduced morbidity of the patients. In the present study 30 untreated histologically proven cases of head and neck cancers were subjected to weekly radiotherapy with adjuvant chemotherapy (cisplatin 30 mg/m2 intravenously). This study group was compared with a group of 30 patients who were given only radiotherapy. Results have shown that combination of chemotherapy with radiotherapy gives a significantly better results in tumour as well as nodal response with minimal toxicities.  相似文献   
30.
PURPOSE: The p21-activated kinase-1 (Pak-1) promotes cell motility and invasiveness. Pak-1 is activated by the Rac, Rho, and Cdc42 small GTPases in response to a variety of stimuli including ras and phosphatidylinositol 3'-kinase/AKT pathway activation. Because Pak-1 plays a central role in regulating cell motility and invasiveness, we sought to determine whether Pak-1 may be involved in the malignant progression of colorectal carcinoma. EXPERIMENTAL DESIGN: Pak-1 expression was examined by immunohistochemistry in archived tissues from normal human colons, tubular and tubulovillous adenomas, invasive adenocarcinomas (stages I-III/IV), and lymph node metastases (184 total specimens from 38 patients). Specific cytoplasmic immunostaining was evaluated for overall intensity and uniformity to derive a combined histoscore (stain intensity x percentage of epithelium stained). RESULTS: Pak-1 expression was increased significantly with colorectal cancer progression from normal tissue to lymph node metastases (P < 0.0001). Furthermore, Pak-1 expression was increased significantly in adenomas, invasive carcinomas, and lymph node metastases compared with normal colon (P < 0.0001). Strikingly, Pak-1 expression was significantly higher in lymph node metastases than in invasive cancers, adenomas, or normal colon (P < 0.0001). Moreover, in patients with multiple lesions representing different stages of disease, Pak-1 expression was increased specifically in the most advanced lesions. CONCLUSIONS: This study demonstrates that Pak-1 expression is increased significantly with malignant progression of human colorectal carcinoma. These data, along with numerous functional studies demonstrating a central role for Pak-1 activity in tumor invasiveness and motility, implicate Pak-1 as an exciting target for therapy of colorectal carcinoma.  相似文献   
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