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排序方式: 共有176条查询结果,搜索用时 15 毫秒
1.
Solitary bronchioloalveolar carcinoma: CT criteria   总被引:14,自引:0,他引:14  
The computed tomographic (CT) scans of 30 patients with solitary bronchioloalveolar carcinoma were reviewed. Common features at CT included the peripheral or subpleural location of a pulmonary mass (25 cases), pseudocavitation (18 cases), heterogeneous attenuation (17 cases), irregular margins forming a star pattern (22 cases), and pleural tags (21 cases). Using these CT criteria, four independent observers attempted to identify cases of bronchioloalveolar carcinoma from a larger sample of lung cancers and benign lesions by categorizing a series of test cases into four probability categories. Although the bronchioloalveolar carcinomas were correctly ranked in the two highest probability categories 75% of the time (in 45 of 60 cases), there was considerable overlap with other lung lesions, particularly with adenocarcinoma and large cell undifferentiated carcinoma. However, even though the typical features of bronchioloalveolar carcinoma are not invariable or highly specific, they are characteristic enough to suggest the diagnosis.  相似文献   
2.
The in vitro mutational spectra of cisplatin [cis-diamminedichloroplatinum(II)] in exon 3 of the human hypoxanthine guanine phosphoribosyltransferase gene in B-lymphoblasts was examined by a combination of polymerase chain reaction and denaturing gradient gel electrophoresis. Several thousand independent mutants were induced at the hypoxanthine guanine phosphoribosyltransferase locus by cisplatin and were selected en masse by addition of 6-thioguanine to the bulk culture. Polymerase chain reaction was used to amplify exon 3 from the complex mutant population, and denaturing gradient gel electrophoresis was used to separate wild-type DNA sequences from mutant sequences. Mutational hotspots were visible as discrete bands on the denaturing gradient gel. Scanning densitometry was used to determine the fraction of the complex population represented by the novel bands. The mutant bands were excised from the denaturing gradient gel and sequenced. In this way, the nature and frequency of mutational hotspots in a population of several thousand mutants were determined. Cisplatin produced several mutational hotspots in exon 3. About 9-10% of the cisplatin-induced mutants had mutations in a GGGGGG sequence (base pairs 207-212). GC----AT substitutions at the second and third guanines in the 5'-GGGGGG-3' run made up about 2 and 4% of the induced mutants, respectively. About 4% of the induced mutants contained a GC----TA substitution at the sixth guanine. About 1% of the cisplatin-induced mutants had an AT----TA transversion in a TAGA sequence (base pair 271; mutated base is underlined). Our results are consistent with mutations occurring at GpG and ApG sites. These nucleotide sequences have been identified as the primary sites of cisplatin adduction.  相似文献   
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The association between MSHR coding region variation and hair colour in humans has been examined by genotyping 25 red haired and 62 non-red Caucasians, all of whom were 12 years of age and members of a twin pair study. Twelve amino acid substitutions were seen at 11 different sites, nine of these being newly described MSHR variants. The previously reported Val92Met allele shows no association with hair colour, but the three alleles Arg151Cys, Arg160Trp and Asp294His were associated with red hair and one Val60Leu variant was most frequent in fair/blonde and light brown hair colours. Variant MSHR genotypes are associated with lighter skin types and red hair (P < 0.001). However, comparison of the MSHR genotypes in dizygotic twin pairs discordant for red hair colour indicates that the MSHR gene cannot be solely responsible for the red hair phenotype, since five of 13 pairs tested had both haplotypes identical by state (with three of the five having both identical by descent). Rather, it is likely that additional modifier genes exist, making variance in the MSHR gene necessary but not always sufficient, for red hair production.   相似文献   
5.
BACKGROUND: The aim of this study was to evaluate the effectiveness of granulocyte-macrophage colony-stimulating factor (GM-CSF) mouthwashes in the prevention of severe mucositis induced by high doses of chemotherapy. PATIENTS AND METHODS: Ninety consecutive patients affected by solid tumors and undergoing high-dose chemotherapy with autologous peripheral blood stem cell transplantation rescue were randomized to receive placebo versus GM-CSF mouthwash 150 micro g/day. Patients were stratified on the basis of the conditioning treatment and the consequent different risk of severe oral mucositis. Treatment was administered from the day after the end of chemotherapy until the resolution of stomatitis and/or neutrophil recovery. RESULTS: The statistical analyses were intention-to-treat and involved all patients who entered the study. The severity of stomatitis was evaluated daily by the physicians according to National Cancer Institute Common Toxicity Criteria. Both study and control groups were compared with respect to the frequency [30% versus 36%, chi(2) exact test, not significant (NS)] and mean duration (4.8 +/- 4.7 versus 4.4 +/- 2.7 days, t-test, NS) of severe stomatitis (grade > or =3). Oral pain was evaluated daily by patients themselves by means of a 10 cm analog visual scale: the mean (+/- standard error of the mean) maximum mucositis scores were 4.8 +/- 3.5 versus 4.2 +/- 3.5 cm (t-test, NS). Furthermore, 15/46 patients in the study group (33%) and 19/44 patients in the control group experienced pain requiring opioids (chi(2) exact test, NS). CONCLUSION: We did not find any evidence to indicate that prophylaxis with GM-CSF mouthwash can help to reduce the severity of mucositis in the setting of the patients we studied.  相似文献   
6.
In two previous studies, we observed that recombinant human interleukin- 3 (IL-3) induced an increase in marrow burst-forming unit-erythroid- derived colonies in vitro in some patients with Diamond-Blackfan anemia (DBA). To determine whether a similar erythropoietic response could be induced in vivo, we treated 13 patients with DBA (aged 4 to 19 years) with two preparations of IL-3. All patients had absent absolute reticulocyte counts and markedly reduced to absent recognizable bone marrow erythroid elements; patients with circulating reticulocytes in the previous 12 months were excluded from study. All patients except 1 had failed steroid therapy and had been transfusion-dependent since infancy; 1 patient was maintained on high-dose prednisone at the time of enrollment. On the first arm of the study, IL-3 (Immunex Corp, Seattle, WA) was administered subcutaneously using a dose escalation regimen of 125 to 500 micrograms/m2/day in divided dosage at 12-hour intervals, coadministered with 1.5 mg/kg/d of oral ferrous sulphate. Of the 13 patients that entered the trial, 4 stopped prematurely because of adverse side effects. In the other 9 evaluable cases, reticulocytes increased transiently in 1 patient from 0 to 65 x 10(9)/L after 35 days of IL-3 therapy at 250 micrograms/m2, but transfusion dependency persisted. One transient peak in absolute reticulocyte count was noted in 6 other patients, but no erythroid response was observed after completion of a full course of IL-3. Oral prednisone at 0.5 mg/kg/d was then coadministered with IL-3 at 500 micrograms/m2 to 5 of the patients without effect, and treatment was stopped. In 2 patients, a second preparation of IL-3 (Sandoz Canada Inc, Dorval, Quebec, Canada) was initiated in a dose escalation regimen of 2.5 to 10 micrograms/kg and was coadministered with ferrous sulphate. No erythroid response was observed in either patient, and in one of the two, alternate-day subcutaneous recombinant erythropoietin at 300 U/kg was administered for 3 weeks in combination with daily IL-3 at 10 micrograms/kg, but no increased erythropoiesis was seen. Significant increases in white blood cell and eosinophil counts during administration of both preparations of IL-3 were observed in all patients. These data show that the response of DBA patients to IL-3 in vivo is heterogeneous and cannot be predicted from in vitro studies. The absence of a corrective effect of IL-3 in these patients with DBA indicates that a deficiency of the cytokine is not central in the pathogenesis of the disorder.  相似文献   
7.
Despite repeated findings of abnormal corpus callosum structure in autism, the developmental trajectories of corpus callosum growth in the disorder have not yet been reported. In this study, we examined corpus callosum size from a developmental perspective across a 30-year age range in a large cross-sectional sample of individuals with autism compared to a typically developing sample. Midsagittal corpus callosum area and the 7 Witelson subregions were examined in 68 males with autism (mean age 14.1 years; range 3–36 years) and 47 males with typical development (mean age 15.3 years; range 4–29 years). Controlling for total brain volume, increased variability in total corpus callosum area was found in autism. In autism, increased midsagittal areas were associated with reduced severity of autism behaviors, higher intelligence, and faster speed of processing (p = 0.003, p = 0.011, p = 0.013, respectively). A trend toward group differences in isthmus development was found (p = 0.029, uncorrected). These results suggest that individuals with autism benefit functionally from increased corpus callosum area. Our cross-sectional examination also shows potential maturational abnormalities in autism, a finding that should be examined further with longitudinal datasets.  相似文献   
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9.
Sixty-four consecutive patients with locally advanced (n = 7) or metastatic breast cancer (n = 57), were treated with a combination of laevofolinic acid 100 mg m-2 plus 5-fluorouracil 340 mg m-2 i.v. on days 1-3, cyclophosphamide 600 mg m-2 i.v. on day 1 and epirubicin 90 mg m-2 i.v. on day 1. Epirubicin dose was progressively escalated by 10 mg m-2 per cycle up to 120 mg m-2 in the absence of dose-limiting toxicities. Granulocyte colony-stimulating factor (G-CSF) was given subcutaneously in order to prevent neutropenia. Epirubicin dosage could be increased to 100 mg m-2 in 53 patients (87%), to 110 mg m-2 in 31 patients (51%) and to 120 mg m-2 in 18 cases (30%). In most patients the dose-limiting toxicity was represented by myelosuppression. A statistically significant correlation was found between median white blood count (WBC) or absolute neutrophil count (ANC) nadir and epirubicin dose level (P = 0.009; P = 0.008). Moreover, a statistically significant correlation was observed between the number of chemotherapeutic cycles, nadir ANC and WBC and the occurrence of anaemia and thrombocytopenia of increasing severity. These data suggest the occurrence of progressive cumulative bone marrow toxicity. Although patients who reached different epirubicin levels showed differences in mean dose intensity, such differences were not statistically significant. No correlation was found between the increase in dose intensity and type, rate or duration of objective responses. In patients with metastatic breast cancer the overall response rate was 72% (95% CL 66-78%) with a 25% complete response rate. Median duration of response was 10 and 13 months respectively for complete and partial responses. All patients with locally advanced breast cancer had an objective response and underwent radical mastectomy. Projected median survival of the whole series of patients with metastatic breast cancer was 20 + months. These data demonstrate that the combination of 5-fluorouracil with laevofolinic acid, cyclophosphamide and epirubicin is very active against metastatic breast cancer. Use of G-CSF allows epirubicin dosage to be increased up to 120 mg m-2 cycle-1, but its use may be linked to the occurrence of sometimes severe cumulative haematological toxicity.  相似文献   
10.
We attempted to analyze whether the use of high-dose cyclophosphamide (CTX 7g/m2, group A) plus hematopoietic growth factor (G-CSF) or G-CSF alone (10 microg/Kg, group B) as a mobilizing regimen, could result in harvesting different numbers of CD34+ cells, committed progenitors and CD34+ cells subsets. The number of CD34+ cells considered as the target for each high-dose chemotherapy was > or = 2 x 10(6) /Kg/bw. Fifteen leukaphereses procedures were necessary in group A, while 16 procedures were performed in group B. We did not observe any difference between the two groups in terms of CD34+ cells/microl in the peripheral blood (117 vs 78; p = NS), whereas in the aphereses product we found a significant difference between the two groups of patients in terms of CD34+ cells (6.41 vs 2.89 x 10(6) /Kg/bw; p = .009), CFU-GM (82.5 vs 52.3 x 10(4) /Kg/bw; p = .04). Interestingly, we noted a different distribution of CD34+/33- cells between the 2 groups (mean value 39% vs 65%; p < .05), whereas we did not find any differences regarding CD34+/38-, CD34+/Thy1+, CD34+/HLADR-. The higher number of CFU-GM/Kg/bw collected in the former group did not translate into a superior plating efficiency (27.75 vs 30.29). Furthermore, we observed a strong correlation between CD34+ cells/microl in the peripheral blood and the total number of CD34+ cells in the leukaphereses product (r = 0.97), whereas this correlation was not found in group B (r = 0.15). In both groups of patients the number of CD34+ cells collected correlated well with CFU-GM (r = 0.93; r = 0.94), but definitely we did not observe any correlation between CD34+ cells/microl and CFU-GM in patients mobilized with G-CSF alone and this did not allow us to predict the harvest accurately. Finally, we evaluated the engraftment kinetics and we did not observe any statistically significant difference between the two groups of patients.  相似文献   
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