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1.
A survey was sent to all registered dentists in British Columbia regarding their training and attitudes in removable prosthodontics. A reasonable number of the questionnaires were returned so that general comments can be made about perceived needs and suggestions to improve training and practice.There was a clear feeling among the dentists surveyed that dental school training had not prepared them adequately for the clinical practice of removable prosthodontics. It was suggested that increased emphasis be placed on both didactic and clinical instruction. Increasing the number and quality of faculty was frequently mentioned.There was a perceived need for integrated instruction with other disciplines and increased emphasis on total patient care, including areas such as nutrition and psychology.In general, removable prosthodontics was felt to be an important area of continuing education. Short courses, study groups, and programs at meetings were perceived to be desirable and necessary.Prosthodontic care was felt to be a significant need of the population. Inadequate training in dental school would be a disservice to both the practitioners and their patients. Access to high-quality dental care is an important aspect of the quality of life, and removable prosthodontics is an integral and important part of dental care.  相似文献   
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OBJECTIVE: To determine whether in the previous National Surgical Adjuvant Breast and Bowel Project (NSABP) studies of node-negative breast cancer there were either cohorts of patients with a prognosis favorable enough to preclude using systemic therapy or subsets of patients who failed to benefit from the treatments. DESIGN: Randomized clinical trials with stratification after surgery. SETTING: NSABP trials at institutions in the United States and Canada. PATIENTS: Data were collected on 731 eligible patients (Protocol B-13) with estrogen-receptor-negative tumors who randomly received either no therapy after surgery or sequential methotrexate and fluorouracil (M----F) followed by leucovorin. Data were also collected on 2834 patients (Protocol B-14) with estrogen-receptor-positive tumors who randomly received either placebo or tamoxifen treatment. The percentage of patients surviving disease-free was determined through 4 years of follow-up using life-table estimates. INTERVENTIONS: Protocol B-13 patients received 12 courses of M----F given intravenously on days 1 and 8 every 4 weeks. Leucovorin therapy was begun 24 hours after M----F administration. Protocol B-14 patients received 5-year treatment with either tamoxifen (10 mg twice daily by mouth) or placebo. RESULTS: When the outcome of untreated patients in either trial was related to the stratification variables, women were found to have a disease-free survival of less than 80% through 4 years of follow-up. This percentage is apt to decrease because the probability of treatment failure increases with time. In both trials, all subsets of women benefited from M----F or tamoxifen therapy. CONCLUSIONS: The disease-free survival of all cohorts of node-negative patients with estrogen-receptor-negative or estrogen-receptor-positive tumors was poor enough to justify systemic treatment. The benefits of the therapies used are insufficient to eliminate the need for assessing putatively better regimens.  相似文献   
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Objective:We aimed to investigate whether individuals with first-episode psychosis (FEP) receiving extended early intervention (EI) were less likely to experience suicidal ideation and behaviors than those transferred to regular care after 2 years of EI. Another objective was to examine the 5-year course of suicidality in FEP.Methods:We conducted a secondary analysis of a randomized controlled trial where 220 patients were randomized after 2 years of EI to receive extended EI or regular care for the subsequent 3 years. Suicidality was rated using the Brief Psychiatric Rating Scale. Linear mixed model analysis was used to study time and group effects on suicidality.Results:Extended EI and regular care groups did not differ on suicidality. There was a small decrease in suicidality over time, F(7, 1038) = 1.84, P = 0.077, with an immediate sharp decline within a month of treatment, followed by stability over the remaining 5 years. Patients who endorsed suicidality at entry (46.6%) had higher baseline positive, negative, and depressive symptoms. The 5-year course fell in 3 groups: never endorsed suicidality (33.9%), endorsed suicidality at low-risk levels (43.1%), and endorsed high-risk levels (23.0%). The high-risk group had a higher proportion of affective versus nonaffective psychosis diagnosis; higher baseline positive and depressive symptoms; higher 5-year mean depression scores, and fewer weeks of positive symptom remission over the 5-year course.Conclusions:The first month of treatment is a critical period for suicide risk in FEP. Although early reductions in suicidality are often maintained, our findings make the case for sustained monitoring for suicide risk management.  相似文献   
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Breast Cancer Research and Treatment - The NSABP B-36 compared four cycles of doxorubicin and cyclophosphamide (AC) with six cycles of 5-fluorouracil, epirubicin, and cyclophosphamide (FEC-100) in...  相似文献   
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Various retroviruses, including human T-cell lymphotropic virus (HTLV-I) and avian sarcoma virus (ASV), can prevent coincubated human peripheral lymphocytes from responding efficiently to phytohaemagglutinin. Addition of high concentrations of T-cell growth factor (TCGF) activity usually overcomes this inhibition. However, such restoration of responsiveness does not occur in the case of HTLV-coincubated cells.  相似文献   
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In 1985 we presented results of a randomized trial involving 1843 women followed for five years that indicated that segmental breast resection (lumpectomy) followed by breast irradiation is appropriate therapy for patients with Stage I or II breast cancer (tumor size, less than or equal to 4 cm), provided that the margins of the resected specimens are free of tumor. Women with positive axillary nodes received adjuvant chemotherapy. Lumpectomy followed by irradiation resulted in a five-year survival rate of 85 percent, as compared with 76 percent for total mastectomy, a rate of survival free of distant disease of 76 percent, as compared with 72 percent, and a disease-free survival rate of 72 percent, as compared with 66 percent. In the current study, we have extended our observations through eight years of follow-up. Ninety percent of the women treated with breast irradiation after lumpectomy remained free of ipsilateral breast tumor, as compared with 61 percent of those not treated with irradiation after lumpectomy (P less than 0.001). Among patients with positive axillary nodes, only 6 percent of those treated with radiation and adjuvant chemotherapy had a recurrence of tumor in the ipsilateral breast. Lumpectomy with or without irradiation of the breast resulted in rates of disease-free survival (58 +/- 2.6 percent), distant-disease-free survival (65 +/- 2.6 percent), and overall survival (71 +/- 2.6 percent) that were not significantly different from those observed after total mastectomy (54 +/- 2.4 percent, 62 +/- 2.3 percent, and 71 +/- 2.4 percent, respectively). There was no significant difference in the rates of distant-disease-free survival (P = 0.2) or survival (P = 0.3) among the women who underwent lumpectomy (with or without irradiation), despite the greater incidence of recurrence of tumor in the ipsilateral breast in those who received no radiation. We conclude that our observations through eight years are consistent with the findings at five years and that these new findings continue to support the use of lumpectomy in patients with Stage I or II breast cancer. We also conclude that irradiation reduces the probability of local recurrence of tumor in patients treated with lumpectomy.  相似文献   
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This review describes current knowledge of changes in natural killer (NK) cell function in acquired immunodeficiency syndrome (AIDS)-related disorders, vis-à-vis associated abnormalities in NK cytolytic function, NK cell subset distribution, NK cytopathology, and lymphokine regulation. NK cells, which are closely associated with large granular lymphocytes, are spontaneously cytotoxic to tumor and virally infected targets. As such, they may play a role in natural resistance to human immunodeficiency virus type 1 (HIV-1)-associated disorders and other opportunistic infections. Yet, peripheral blood NK activity is frequently reduced in patients with HIV-1-induced disease. NK cells are heterogeneous both with respect to their expression of serologically defined membrane antigens and functional activity. In AIDS-related syndromes, there appears to be a diminution of the NK pool (CD16+ cells) involved in cytolytic function, while there is an elevation of the NK pool that coexpresses NK (Leu 7+) and T (CD8+) cell markers, which show little or no involvement in cytolytic function. The impairment of in vitro NK function is not associated with a reduced frequency of lytic conjugates of effectors and target cells nor with the recycling capacity of these effector cells but rather is associated with defects in the NK cell lytic machinery following formation of such conjugates. NK cells in AIDS patients show an impairment in effector cell microtubule rearrangement following target cell interaction. The causes of NK cell dysfunction in AIDS-related disorders remain unknown. NK cells do not appear to express the CD4 epitope of the HIV receptor, nor have they been demonstrated to be susceptible to infection by HIV-1. There appears to be a preponderance of immature NK cells and a lymphokine imbalance in patients with HIV-1 associated disease. Interleukin-2 can partially restore diminished in vitro NK function. Elucidation of the involvement of the NK compartment in natural resistance to HIV-1 merits further investigation.  相似文献   
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We examined 100 breast cancers for retinoblastoma (Rb) and p53 protein expression by immunohistochemistry using the PMG3.245 and PAb 1801 antibodies. We assessed percentages of reactive cells and their intensity, as well as staining patterns. The results were correlated with neu protein reactivity and a panel of variables, including age, tumor size and type, nuclear grade, estrogen receptor/progesterone receptor content, and lymph node status. Retinoblastoma protein negativity, either partial or complete, was noted in 47% of cases. Surprisingly, a relatively stronger Rb reaction was seen in some high nuclear grade tumors. p53 positivity was found in 23% of cases and was a significant predictor of Rb loss. p53 also was correlated with poorly differentiated (nuclear grade III) neoplasms and neu expression but not with negative ER status. Tissue distribution profiles for Rb-negative and p53-positive cells were variable in this series, with both uniform and heterogeneous patterns observed. This suggests that Rb and p53 alterations may represent early or late events in transformation. Our findings further implicate Rb and p53 derangements in mammary oncogenesis.  相似文献   
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In 1976 we began a randomized trial to evaluate breast conservation by a segmental mastectomy in the treatment of Stage I and II breast tumors less than or equal to 4 cm in size. The operation removes only sufficient tissue to ensure that margins of resected specimens are free of tumor. Women were randomly assigned to total mastectomy, segmental mastectomy alone, or segmental mastectomy followed by breast irradiation. All patients had axillary dissections, and patients with positive nodes received chemotherapy. Life-table estimates based on data from 1843 women indicated that treatment by segmental mastectomy, with or without breast irradiation, resulted in disease-free, distant-disease-free, and overall survival at five years that was no worse than that after total breast removal. In fact, disease-free survival after segmental mastectomy plus radiation was better than disease-free survival after total mastectomy (P = 0.04), and overall survival after segmental mastectomy, with or without radiation, was better than overall survival after total mastectomy (P = 0.07, and 0.06, respectively). A total of 92.3 per cent of women treated with radiation remained free of breast tumor at five years, as compared with 72.1 per cent of those receiving no radiation (P less than 0.001). Among patients with positive nodes 97.9 per cent of women treated with radiation and 63.8 per cent of those receiving no radiation remained tumor-free (P less than 0.001), although both groups received chemotherapy. We conclude that segmental mastectomy, followed by breast irradiation in all patients and adjuvant chemotherapy in women with positive nodes, is appropriate therapy for Stage I and II breast tumors less than or equal to 4 cm, provided that margins of resected specimens are free of tumor.  相似文献   
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