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121.
Fifty-nine Fischer rat tumors and eleven Hooded rat tumors induced by intramuscular injection of Ni3S2 were examined and their histopathologic and cytologic characteristics studied. Nine out of eleven Hooded rat tumors metastasized whereas 15 out of 59 Fischer rat tumors metastasized within 30 days. Histopathological characterization of the Ni3S2-induced tumors was made according to their preponderant cellular constitution. They were grouped into six types: well-differentiated rhabdomyosarcomas, poorly-differentiated rhabdomyosarcomas, embryonal rhabdomyosarcomas, mesenchymal tumors, leiomyosarcoma-like tumors and fibrosarcoma-like tumors. Forty-seven of total of 70 were rhabdomyosarcomas. Tumors with shorter latent periods in Fischer rats and tumors with fleshy and soft texture demonstrated a higher incidence of metastases.  相似文献   
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The effects of anemia during lead exposures were studied using an infant baboon animal model. When the hemoglobin concentration was reduced to less than 70% of normal, a marked blood lead increase was observed and the free erythrocyte porphyrin value, aminolevulinic acid dehydratase activity and reticulocyte counts increased. Special emphasis should be placed on nutritional effects in lead exposures.  相似文献   
124.
Blood flow: a mediator of ovarian function   总被引:1,自引:0,他引:1  
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We report the 14th case of myelolipoma of the adrenal gland. Recommendations for appropriate diagnostic and therapeutic methods are made. Myelolipoma of the adrenal gland is a rare non-functioning tumor composed of lipoid and hematopoietic elements. The most consistent complaint is abdominal pain caused by hemorrhage within the tumor. We identified an association with obesity and hypertension. Ultrasound combined with computed tomography is useful in diagnosis. With expanded use of these studies, myelolipoma will be recognized more frequently. Definitive diagnosis and treatment are accomplished by simple excision; radical surgery is unnecessary.  相似文献   
127.
The clinical, surgical, and pathologic findings in a five year prospective study of 192 patients referred with a high probability of pancreatic cancer are reported. We have defined the requirements of any pancreatic imaging procedure as its ability to distinguish a normal pancreas from pancreatic cancer or chronic pancreatitis and the capability of detecting tumors less than 5 cm in diameter. There was a 47 percent incidence of pancreatic disease (27 percent pancreatic cancer and 20 percent chronic pancreatitis). Prospective radionuclide imaging as routinely performed was found to be of little clinical value in this patient population; it was neither specific nor sensitive to pancreatic cancer or chronic pancreatitis. Preliminary data with longitudinal multiplane emission tomography show an improved diagnostic accuracy and the ability to detect resectable tumors, but its efficacy needs to be prospectively compared with other screening tests on a carefully defined patient population.  相似文献   
128.
Twenty-four high-risk Ewing's sarcoma patients were treatedf on an intensive combined modality protocol including low-dose fractionated total body irradiation (TBI) and autologous bone marrow infusion (ABMI). Twenty patients (83%) achieved a complete clinical response to the primary and/or metastatic sites following induction therapy. The median disease-free interval was 18 months, and nine patients remain disease-free with a follow-up of 22 to 72 months. Local failure as a manifestation of initial relapse occurred in only three patients (15%), each having synchronous distant failure. Eight patients failed initially with only distant metastases, usually within 1-2 years following a complete clinical response. Two patients with a single metastasis were again rendered disease-free and remain free from second relapse with 18 and 30 months follow-up. No other relapsed patient was able to be rendered disease-free, and most died of progressive disease within 6 to 12 months of relapse. Two patterns of granulocyte recovery following consolidative therapy (include TBI) and ABMI were recognized. Seventeen patients reached a total granulocyte count of >500 cells/mm3 within 4 weeks of ABMI (early graulocyte recovery), while seven patients required >4 weeks from ABMI (late granulocyte recovery). The time of platelet recovery (>50,000/mm3) was different for the groups with early and late granulocyte recovery (25 days vs. 54 days, p <.001). Six of seven patients with late granulocyte recovery received locl high-dose irratiation to >1/2 pelvis prior to bone marrow storage. Patients with late recovery did not tolerate maintenance chemotherapy. However, there was no difference in disease-free and overall survival, when compaing the groups with early and late granulocyte recovery. We conclude that these high-risk Ewing's sarcoma patients remain a poor-prognosis group in spite of intensive combined modality therapy include low-dose TBI. The control of microscopic systemic disease remains the major challenge to improving the cure rate. A new combined modality protocol with high-dose 'therapeutic' TBI (800 rad/2 fractions) is being used and the protocol design is outlined.  相似文献   
129.
This paper discusses two cases of bilateral subcapital fracture of the proximal femur as a complication of myelography with Conray 60. The literature is reviewed.  相似文献   
130.
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