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1.
H Zincke 《Cancer》1992,70(11):2742-2743
From 1972 to 1986, 354 patients with local and locoregional adenocarcinoma of the prostate were treated with curative intent at the Medical College of Wisconsin. Fifty-six of these patients were found to have Stage D1 disease (evidence of pelvic lymph node involvement). Using external beam irradiation alone, these patients were treated aggressively to the pelvis followed by a boost to the prostate. The median dose to the prostate was 6800 cGy, and to the pelvis, it was 5040 cGy. The median period of observation after treatment was 9 years. Actuarial survival was 76% at 5 years, and disease-free survival was 61% at 5 years. Twenty-three patients had biopsy-proved pelvic lymph node involvement; the other 33 were considered to have Stage D1 disease based on abnormal computed tomographic scans, lymphangiograms, or both. Actuarial survival and disease-free survival were calculated for both groups separately, and there was no statistical difference in the results. Major complications occurred in 3.6% (two patients) of this group with Stage D1 disease. These results support the continued use of aggressive external beam irradiation in patients with locoregional adenocarcinoma of the prostate.  相似文献   
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PURPOSES: In this study we present our experience with treating persistent sacral and perineal defects secondary to radiation and abdominoperineal resection with or without sacrectomy. METHODS: Fifteen consecutive patients were treated with an inferiorly based transpelvic rectus abdominis muscle or musculocutaneous flap. RESULTS: Fourteen of the 15 patients achieved healing, and 7 patients had no complications. The remaining eight patients required one or more operative debridements and/or prolonged wound care to accomplish a healed wound. Our technique for the dissection and insetting of the transpelvic muscle flap is presented. CONCLUSION: The difficult postirradiated perineal and sacral wounds can be healed with persistent surgical attention to adequate debridement, control of infections, and a well-vascularized muscle flap. The most satisfying aspects for patients are the discontinuance of foul-smelling discharge, discontinuation of multiple, daily dressing changes, and reduction in the degree of chronic pain.Read at the meeting of the Midwestern Association of Plastic Surgeons, Bismarck, North Dakota, June 15 to 18, 1992.  相似文献   
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The presence of checkpoint mechanisms which are able to recognize damaged chromatin and thereafter to prevent exit from metaphase I has been investigated in giant mouse oocytes produced by fusion of a normal metaphase I oocyte with an equivalent oocyte with damaged chromatin. The presence of damaged chromatin did not prevent the onset of anaphase I in both sets of chromatin in the fused cells. Interestingly, fused or unfused cells containing only damaged chromatin failed to enter anaphase and persisted instead in a metaphase-like state. These results demonstrate the fragility of checkpoint controls in mammalian female germ cells.   相似文献   
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PURPOSE: The purpose of this study was to identify pretherapy factors associated with pelvic lymph node involvement (LNI) in patients with localized prostatic carcinoma (CaP), and to develop a model that would allow for estimation of this risk at the time of initial diagnosis. METHODS AND MATERIALS: Between January 1988 and December 1992, 2439 patients with clinical Stage T1a-3cN0-XM0 CaP underwent radical retropubic prostatectomy and bilateral pelvic lymph node dissection as sole initial therapy at a single medical institution. Preoperative factors were evaluated for their association with pelvic LNI in univariate and multivariate logistic regression analysis. A model was developed that incorporated independent predictive variables, and probability plots were generated to estimate the likelihood of pelvic LNI in the patient with a new diagnosis of localized CaP. RESULTS: Within clinical tumor stage, three groups (Tla-2a, T2b-c, and T3) were identified in which the observed rate of pelvic LNI was distinctly different. Gleason primary grades were also combined (1-2, 3, and 4-5) because of a similar observation. Univariate analysis identified clinical tumor stage (p < 0.0001), Gleason primary grade (p < 0.0001), and serum prostate-specific antigen (p < 0.0001) as factors associated with pelvic LNI. Each of these variables retained independent significance (p < or = 0.0002) in the multivariate model. Patient age (p = 0.12) and history of prior transurethral resection of the prostate (p = 0.36) were not found to correlate with this endpoint. Probability plots provided an estimate of the likelihood for pelvic LNI according to the combination of pretherapy clinical tumor stage, Gleason primary grade, and serum prostate-specific antigen level. CONCLUSION: Clinical tumor stage as determined by digital rectal examination, Gleason primary grade of the diagnostic biopsy specimen, and pretherapy serum prostate-specific antigen value can be combined to estimate the probability of pelvic LNI for the patient with a new diagnosis of localized CaP. This information may be of value in directing the pretherapy diagnostic evaluation, as an aid in radiation therapy treatment planning, and in the conduct of clinical research efforts.  相似文献   
7.

Purpose

Age-specific prostate specific antigen (PSA) reference ranges have been suggested to account for the age-dependent nature of the serum PSA concentration. It has been hypothesized that reference ranges of 0 to 2.5 ng./ml. serum PSA (40 to 49 years), 0 to 3.5 ng./ml. (50 to 59 years), 0 to 4.5 ng./ml. (60 to 69 years) and 0 to 6.5 ng./ml. (70 to 79 years) would detect fewer (potentially insignificant) prostate cancers in older men and more (potentially curable) cancers in younger men.

Materials and Methods

To investigate the pathological stage of tumors that would be affected by the use of age-specific PSA reference ranges, we reviewed the medical records for 4,597 men with clinically localized (stage T1c, T2 or T3a) prostate cancer, with an average age of 62 plus/minus 7 years (range 38 to 76), who underwent radical prostatectomy between 1984 and 1994 at our institutions. Favorable pathological results were defined as organ-confined disease or capsular perforation with a Gleason score of less than 7, and unfavorable pathological results were defined as capsular perforation with a Gleason score of 7 or more, seminal vesicle invasion or lymph node involvement.

Results

Overall, 18 percent of the men had PSA levels less than the standard PSA reference range (4.0 ng./ml.) compared to 22 percent when using the age-specific ranges. There were 74 more cancers detected in men younger than 60 years with the use of age-specific ranges, of which 81 percent had favorable pathological results. Among the men 60 years or older, 191 of 252 cancers (76 percent) not detected by using age-specific ranges were of favorable pathological status. Of those cancers not detected in older men with the age-specific ranges less than 3 percent were also stage T1c and 95 percent of these undetected T1c cancers were of favorable pathological status. Age-specific PSA reference ranges increased the potential for detection of prostate cancer by 18 percent in the younger men and decreased the detection by 22 percent in the older men.

Conclusions

Among these men with clinically localized prostate cancer, age-specific PSA reference ranges increased the detection of more potentially curable tumors in young men and decreased the detection of less advanced tumors in the older men compared to the standard reference range of 4.0 ng./ml. Among older men with nonpalpable (stage T1c) tumors age-specific PSA reference ranges would have detected fewer tumors. However, 95 percent of these “missed” tumors would have had favorable pathological findings.  相似文献   
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PURPOSE: The accurate prediction of pathological stage of prostate cancer using preoperative factors is a critical aspect of treatment. In 1997 Partin et al published tables predicting pathological stage using clinical stage, Gleason score and prostate specific antigen (PSA). We tested the validity of the Partin tables. MATERIALS AND METHODS: From 1990 to 1996 inclusively 5,780 patients underwent bilateral pelvic lymphadenectomy and radical prostatectomy for prostate cancer at the Mayo Clinic. However, only 2,475 of these patients met all inclusion criteria of no preoperative treatment, known biopsy Gleason score, available preoperative PSA done either before biopsy or more than 28 days after biopsy and clinical stage T1, T2 or T3a. Among the 2,475 patients 15 had positive lymph nodes and planned prostatectomy was abandoned. The receiver operating characteristics (ROC) curve area, observed and predicted Partin rates of each pathological stage, and positive and negative predictive values were used to compare the Mayo study to the Partin tables. RESULTS: The distribution of pathological stage was organ confined in 67% of Mayo cases versus 48% in the Partin study, extracapsular without seminal vesicle or node involvement in 18% versus 40%, seminal vesicle involvement without nodes in 9% versus 7% and were positive nodes in 6% versus 5%. Using the predicted probabilities of Partin et al the ROC curve area for predicted node positive disease was 0.84 for Mayo cases compared to an estimated 0. 82 in the Partin series. The ROC curve area for predicting organ confined cancer was 0.76 for the Mayo Clinic compared to an estimated 0.73 for the Partin series. The observed rates of node positive disease were similar to those predicted (Partin) based on clinical stage, PSA and Gleason score. For organ confined disease Mayo rates were consistently higher than those predicted from the Partin series using a cut point of 0.50 or greater. Positive and negative predictive values were 0.83 and 0.49 versus 0.63 and 0.70 for the Mayo Clinic and Partin series. CONCLUSIONS: Our study provides strong evidence that sensitivity and specificity of the Partin tables for external clinical sites are similar to what was reported.  相似文献   
10.
Broudy  VC; Lin  NL; Fox  N; Taga  T; Saito  M; Kaushansky  K 《Blood》1996,88(6):2026-2032
Thrombopoietin (Tpo), the ligand for the c-Mpl receptor, is a major regulator of megakaryopoiesis. Treatment of mice with Tpo raises the platelet count fourfold within a few days. Conversely, c-mpl knock-out mice have platelet counts that are 15% that of normal. The subunit structure of the c-Mpl receptor is not fully understood. Some cytokines that stimulate megakaryopoiesis (IL-6, IL-11, leukemia inhibitory factor, and oncostatin M) bind to receptors that use gp130 as a signal transduction subunit. For these reasons, we determined whether gp130 function was required for Tpo-induced signal transduction. Murine marrow cells were cultured in semi-solid media in the presence of Tpo or IL-3, with or without a neutralizing anti-gp130 monoclonal antibody (RX187) or a soluble form of c-Mpl receptor (soluble Mpl) that blocks Tpo bioactivity, and the numbers of colony-forming unit-megakaryocyte (CFU-Meg) colonies were counted on day 5. Murine marrow cells were also cultured in suspension under serum-free conditions for 5 days, and megakaryocyte DNA content was measured by flow cytometry, as an index of nuclear maturation. The addition of RX187 did not block Tpo-induced CFU-Meg colony growth nor CFU-Meg nuclear maturation in suspension culture. However, IL-3-induced CFU-Meg colony growth and megakaryocyte nuclear maturation decreased in the presence of RX187. Soluble Mpl completely ablated Tpo-induced CFU-Meg growth, and partially blocked IL- 3-stimulated CFU-Meg growth. Thus the effects of Tpo on megakaryopoiesis in vitro do not depend on cytokines that signal through gp130. Furthermore, it is unlikely that gp 130 serves as a beta chain for the c-Mpl receptor, as Tpo signalling is unimpaired in the presence of RX187. In contrast, the effects of IL-3 on CFU-Meg growth are mediated in part through Tpo and through gp130-signalling cytokines.  相似文献   
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