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871.
Immunoelectron microscopic studies in human neutrophils showed that FcRIII was present on the plasma membrane, in the Golgi complex, and in many small vesicles (120 to 180 nm). FcRIII was not found in specific or azurophilic granules as shown by immunogold double-labeling experiments, visualizing both FcRIII and either lactoferrin (a marker of specific granules) or myeloperoxidase (a marker for azurophilic granules). Because the occurrence of FcRIII in the Golgi complex suggested that biosynthesis of this receptor occurs in these cells, metabolic labeling experiments were performed. Immunoprecipitation of FcRIII from NP-40 lysates of cells labeled with 35S-methionine showed a diffuse 50- to 70-Kd band corresponding with the band noted after immunoprecipitation of FcRIII from surface iodinated cells. These findings show that de novo synthesis of FcRIII occurs in neutrophils and suggest that at least some of the small vesicles containing FcRIII derive from the Golgi complex and thus are involved in transport of newly synthesized FcRIII to the plasma membrane.  相似文献   
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Petursson  SR; Chervenick  PA 《Blood》1985,65(6):1460-1468
Megakaryocytopoiesis and granulopoiesis of marrow cells from W/Wv mice were studied using a continuous liquid marrow culture system. Cells in the suspension phase were assayed weekly over a 16-week period for total nucleated cells, megakaryocytes, granulocytes, megakaryocytes and granulocyte-macrophage progenitor cells (CFU-Ms, CFU-GMs), and spleen colony-forming cells (CFU-Ss). Without hydrocortisone supplementation, proliferation of megakaryocytes, granulocytes, and their progenitor cells was significantly less in W/Wv cultures than in +/+ cultures. These cells became undetectable in both W/Wv and +/+ cultures at seven to 11 weeks in culture, after which only monocytes and macrophages proliferated in the cultures. Treatment of cultures with hydrocortisone improved megakaryocytopoiesis and granulopoiesis in both W/Wv and +/+ cultures. Following an initial lag phase of three to four weeks, proliferation of megakaryocytes, granulocytes, and their progenitor cells in W/Wv cultures equalled that observed in +/+ cultures and was sustained for 16 to 24 weeks. This improvement was associated with a sustained reduction in monocytes and macrophages. Despite improvements in megakaryocytopoiesis and granulopoiesis, production of macroscopic and microscopic spleen colonies by cells from W/Wv cultures remained severely reduced or absent. Studies of DNA synthesis rates of fresh marrow cells indicated that significantly fewer CFU-Ms and CFU-GMs were in cycle in W/Wv mice compared with +/+ mice. However, in hydrocortisone-treated W/Wv cultures, DNA synthesis rates of CFU-Ms and CFU-GMs increased markedly and equalled those observed for +/+ cultures. These results suggest that the improvements in megakaryocytopoiesis and granulopoiesis in hydrocortisone-treated liquid cultures is associated with a reduction in monocytes and macrophages and that progenitor cells of W/Wv mice have a proliferative defect that is correctable by hydrocortisone treatment in vitro.  相似文献   
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BACKGROUND:

The requirement that patients give up curative treatment makes hospice enrollment unappealing for some patients and may particularly limit use among African‐American patients. The current study was conducted to determine whether African‐American patients with cancer are more likely than white patients to have preferences for cancer treatment that exclude them from hospice and whether they are less likely to want specific hospice services.

METHODS:

Two hundred eighty‐three patients who were receiving treatment for cancer at 6 oncology clinics within the University of Pennsylvania Cancer Network completed conjoint interviews measuring their perceived need for 5 hospice services and their preferences for continuing cancer treatment. Patients were followed for 6 months or until death.

RESULTS:

African‐American patients had stronger preferences for continuing their cancer treatments on a 7‐point scale even after adjusting for age, sex, finances, education, Eastern Cooperative Oncology Group performance status, quality of life, and physical and psychologic symptom burden (adjusted mean score, 4.75 vs 3.96; β coefficient, 0.82; 95% confidence interval, 0.22‐1.41 [P = .007]). African‐American patients also had greater perceived needs for hospice services after adjusting for these characteristics (adjusted mean score, 2.31 vs 1.83; β coefficient, 0.51; 95% confidence interval, 0.11‐0.92 [P = .01]). However, this effect disappeared after adjusting for household finances.

CONCLUSIONS:

Hospice eligibility criteria may exclude African‐American patients disproportionately despite greater perceived needs for hospice services in this population. The mechanisms driving this health disparity likely include both cultural differences and economic characteristics, and consideration should be given to redesigning hospice eligibility criteria. Cancer 2009. © 2008 American Cancer Society.  相似文献   
876.
Neurofibromatosis (NF) is one of the most common genetic disorders. Inherited in an autosomal dominant fashion, this phacomatosis is classified into two genetically distinct subtypes characterized by multiple cutaneous lesions and tumors of the peripheral and central nervous system. Neurofibromatosis type 1 (NF1), also referred to as Recklinghausen''s disease, affects about 1 in 3500 individuals and presents with a variety of characteristic abnormalities of the skin and the peripheral nervous system. Neurofibromatosis type 2 (NF2), previously termed central neurofibromatosis, is much more rare occurring in less than 1 in 25 000 individuals. Often first clinical signs of NF2 become apparent in the late teens with a sudden loss of hearing due to the development of bi-or unilateral vestibular schwannomas. In addition NF2 patients may suffer from further nervous tissue tumors such as meningiomas or gliomas. This review summarizes the characteristic features of the two forms of NF and outlines commonalities and distinctions between NF1 and NF2.  相似文献   
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The management of skeletal metastases can be challenging for the orthopaedic surgeon. They represent a significant source of pain and disability for cancer patients, adding to the morbidity of their condition. Treatment is directed at the alleviation of symptoms and the restoration of function. Metastatic involvement of the proximal humerus can be especially debilitating, having the potential to cause severe pain and loss of function. We present a report of three such cases where reverse geometry proximal shoulder replacement was used to provide a pain free functional range of movement in patients with concomitant rotator cuff disease. In all cases, significant symptomatic relief was achieved postoperatively with preservation of upper limb function. No surgical complications were noted. It is our belief that this novel surgical strategy provides a valuable and effective option for the management of proximal humeral metastatic disease in the rotator cuff deficient patient.  相似文献   
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