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101.
102.
The morphological features of kidney neoplasms induced by ethylnitrosourea (ENU) with or without prior irradiation were examined with a view to comparing them with human renal tumors of childhood. The rat renal tumors consisted of poorly differentiated, highly mitotic mesenchymal cells frequently attempting to differentiate along fibroblastic and myofibroblastic lineages. Though the host renal tubules were frequently entrapped in these tumors, immature tubules and islands of epithelial cells occasionally were seen to form an integral part of the neoplasms. Rarely, adenomatous areas surrounded by mesenchymal proliferation were observed. None of the tumors had the blastemal component that is the hallmark of nephroblastoma. The rat mesenchymal tumors resembled the human congenital mesoblastic nephroma.  相似文献   
103.
104.
The records of seventeen neonates (13 males and 4 females) with osteomyelitis and septic arthritis, who were admitted over a 3 year period, were reviewed. Neither prematurity nor low birth weight seemed to be a predisposing factor. The majority of the neonates (88.2%) had some antecedent illness or were subjected to certain procedures in the neonatal period. Paucity of movement of limb, fever and local swelling of the joint were the most frequent presenting symptoms. Deep soft tissue swelling was the frequently noted radiographic change (58.8%). Bone scintigraphy was abnormal in 7 out of 11 cases. Of the 21 sites involved, femur and humerus accounted for 76.1% of cases. Four of seventeen neonates had multiple bone involvement. Arthritis was present in fifteen neonates. Of the organisms isolated, Staphylococcus aureus was the commonest.  相似文献   
105.
This study examines union certification elections in hospitals from October 1994 to September 1997. Results indicate that union win rates were significantly higher in single-union elections and larger bargaining units. On the other hand, union win rates were significantly lower in church-related hospitals and hospitals that belonged to a health care system or had higher payroll costs. Unions also appeared to win elections at a higher rate in this period than in the past.  相似文献   
106.
In the present study 350 school boys and 350 school girls in the age group of 5 to 12 yr were studied. It was observed that there is parallel progressive increase in physical growth and pulmonary function in this age group. There was positive significant correlation of FEV1 with height and weight.  相似文献   
107.
It is becoming increasingly evident that reactive oxygen species (ROS) act at different stages of carcinogenesis, and thus play multiple roles in oncogenesis. In addition to being mutagenic and initiating tumors, ROS or carcinogens that result in ROS generation may affect tumor promotion and progression through varied effects on growth promoting, growth inhibitory, or apoptotic signaling pathways.  相似文献   
108.
The lung represents an attractive target for delivering gene therapy to achieve local and potentially systemic delivery of gene products. The objective of this study was to evaluate the feasibility of the AERx Pulmonary Delivery System for delivering nonviral gene therapy formulations to the lung. We found that "naked" DNA undergoes degradation following aerosolization through the AERx nozzle system. However, DNA formulated with a molar excess of cationic lipids (lipoplexes) showed no loss of integrity. In addition, the lipoplexes showed no significant change in particle size, zeta (zeta) potential, or degree of complexation following extrusion. The data suggest that complexation with cationic lipids had a protective effect on the formulation following extrusion. In addition, there was no significant change in the potency of the formulation as determined by a transfection study in A-549 cells in culture. We also found that DNA formulations prepared in lactose were aerosolized poorly. Significant improvements in aerosolization efficiency were seen when electrolytes such as NaCl were added to the formulation. In conclusion, the data suggest that delivery of lipoplexes using the AERx Pulmonary Delivery System may be a viable approach for pulmonary gene therapy.  相似文献   
109.
BACKGROUND: Small cell carcinoma of the esophagus is a rare disease, characterized by aggressive progression. It has a high incidence of metastatic disease at presentation and a poor overall prognosis. Treatment protocols are not well established because of the paucity of cases and a lack of large studies. METHODS: We performed a retrospective review of all patients with small cell carcinoma of the esophagus diagnosed at the Tata Memorial Hospital between 1985 and 2001. We retrieved and analyzed data regarding demographic details, diagnosis, staging, type of treatment, and overall survival. RESULTS: Eighteen patients with a mean age of 62 years (range 48 to 80 years) diagnosed as having small cell carcinoma of the esophagus were analyzed. The group included 13 men and 5 women. Seven of the 18 patients (39%) presented with metastatic disease including 5 patients (28%) with liver metastases. Four patients were treated with surgery, with or without chemotherapy or radiotherapy. Three patients were treated with combination chemoradiotherapy, 2 patients with chemotherapy alone, and 5 patients with radiotherapy alone. Four patients with advanced disease and poor general condition were not offered any treatment. The overall median survival of our patients was 6 months. Patients treated with surgery and chemotherapy had a better overall survival. CONCLUSIONS: Small cell carcinoma of the esophagus should be regarded as a systemic disease with a high distant failure rate. Treatment strategies hence must incorporate systemic chemotherapy along with radical surgery or radiotherapy as part of a multimodality approach.  相似文献   
110.
Amersdorfer P  Wong C  Smith T  Chen S  Deshpande S  Sheridan R  Marks JD 《Vaccine》2002,20(11-12):1640-1648
Understanding the antibody response in botulinum intoxication is important for vaccine design and passive prophylaxis. To investigate this activity, we have studied the immune response to BoNT/A (botulinum neurotoxin serotype A) binding domain (HC) at the molecular level using phage display. The scFv antibodies were isolated from V-gene repertoires prepared from (a) human volunteer immunized with pentavalent botulinum toxoid and (b) non-immune human peripheral blood lymphocytes and spleenocytes. A large panel of serotype specific phage expressing botulinum binding scFv could be selected from both libraries. Epitope mapping of immune scFv binders towards BoNT/A HC revealed surprisingly a limited number of scFv recognizing conformational epitopes that corresponded to two distinct groups, clusters I and II. Only scFv from cluster I exhibited neutralizing activity in the mouse hemidiaphragm assay. Anti- BoNT/A HC clones derived from a non-immune library could be conveniently grouped into clusters III-XI and appeared to share no overlapping epitopes with cluster I or II. In addition they showed no neutralization of toxin at biologically significant concentrations. We therefore suggest that a vaccine based on the pentavalent botulinum toxoid directs the humoral immune response to a limited number of immunodominant epitopes exposed on the binding domain HC.  相似文献   
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