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31.
Fat necrosis in the scrotum is a rare lesion seen only before the age of puberty. The authors add one case of their own to three earlier reports. Common to most patients reported are the strict age limits between 9 and 12 years at the onset, exposure to cold, a tender mass in close connection with one or both testicles, and difficulties in differentiating this condition preoperatively from other forms of acute scrotum. Microscopic similarities with cold panniculitis are discussed. Offrint requests to: J. Viljanto  相似文献   
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BACKGROUND: The cause, pathogenesis, and appropriate treatment of meniscal cysts remain controversial. PURPOSE: We wanted to evaluate the results of treatment of meniscal cysts with two different operative procedures. STUDY DESIGN: Prospective cohort study. METHODS: Two different operative procedures were compared. Sixteen patients (group 1) had an open excision of the cyst performed in addition to arthroscopic examination of the knee. Nineteen patients (group 2) were treated entirely arthroscopically. The postoperative treatment course was the same for both groups. The mean length of follow-up was 33 months. RESULTS: The results were excellent or good in 86% of the patients (30 of 35) and were equally good for both procedures. Patients with degenerative changes of the knee joint seemed to have a less favorable outcome. CONCLUSIONS: Good or excellent results can be expected from either open or arthroscopic treatment of meniscal cysts.  相似文献   
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An important anticarcinogenic function of the mismatch repair (MMR) system is its role in preventing recombination between similar, but nonidentical (homeologous) sequences, thus preventing chromosomal rearrangements. We recently identified a novel chromosomal instability (CIN) phenotype in an MMR defective colon cancer cell line (HCA7) characterized by an ongoing tendency to multiple reciprocal chromosomal translocations. To analyse the relation between MMR and chromosomal changes more closely, the HCA7 stem clone was divided into three stocks. The first was stably transfected with MLH1 expression plasmid, the second was regularly exposed to the demethylating agent 5-azacytidin to re-express the hypermethylated MLH1 gene, and the third was an unmanipulated control stock. All stocks were propagated in vitro for 55-80 passages and, furthermore, some of the early passages were irradiated to induce DNA double-strand breaks. Multiplex-fluorescent in situ hybridization (M-FISH) analysis showed that all three stocks acquired varying numbers of reciprocal translocations and other structural changes at some point. Interestingly, the control stock, which is MMR defective, maintained its numerical chromosomal stability, while some of the MMR-proficient clones showed additional numerical instability. Although the control stock was less sensitive to irradiation, its surviving clones showed marked stability of chromosome structure and number compared to the MMR-competent stocks. These results show that restoring MMR does not prevent the development of reciprocal translocations but rather predisposes cells to numerical CIN after irradiation. Thus, the accumulating data suggest that MMR defect may not be necessary for the development of reciprocal chromosomal translocations but might be permissive.  相似文献   
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A considerable fraction of families with HNPCC shows no germline mismatch repair (MMR) gene mutations. We previously detected 'hidden' MMR gene defects in 42% of such families, leaving the remaining 58% 'truly' mutation negative. Here, we characterized 50 colorectal carcinomas and five adenomas arising in HNPCC families; 24 truly MMR gene mutation negative and 31 MMR gene mutation positive. Among 31 tumors from MMR gene mutation positive families, 25 (81%) had active Wnt signaling as indicated by aberrant beta-catenin localization with or without CTNNB1 mutations, compared to only 7/18 tumors from MMR gene mutation negative families (39%; P=0.005). CGH studies revealed stable profiles in 9/16 (56%) of MMR gene mutation negative tumors, which was significantly associated with membranous beta-catenin (P=0.005). Tumors with membranous beta-catenin from the MMR gene mutation negative group also showed low frequency of TP53 mutations compared to those with nuclear beta-catenin. Thus, a majority of the MMR gene mutation negative cases exhibited a novel molecular pattern characterized by the paucity of changes in common pathways to colorectal carcinogenesis. This feature distinguishes the MMR gene mutation negative families from both HNPCC families linked to MMR defects and sporadic cases, suggesting the involvement of novel predisposition genes and pathways in such families.  相似文献   
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Exertion injuries in adolescent athletes.   总被引:3,自引:3,他引:0       下载免费PDF全文
A series of 147 cases of exertion injuries in less than or equal to 15 years old athletes is presented. All injuries occurred during training or athletic performances without trauma and caused symptoms that prevented athletic exercises. There were 67 girls (46%) and 80 boys (54%) in the material. About 90% of them had been training for more than one year before the onset of the symptoms; 65% were interested in track and field athletics, 13% in ball games, 11% in skiing, 4% in swimming, and 3% in orienteering. The rest were interested in other sports. About 33% of the injuries were growth disturbances or osteochondroses seen also in other children. About 15% were anomalies, deformities or earlier osteochondritic changes, which caused first symptoms during the physical exercise; 50% were typical overuse injuries that may bother adult athletes, too; 43% of the injuries were localized in ankle, foot and heel, 31% in knee, 8% in back and trunk, 7% in pelvic and hip region, and the rest in other parts of the body. The injuries were generally slight, no permanent disability was noticed. Rest and conservation therapy cured most cases; operative treatment was used in only eight cases.  相似文献   
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To identify new potential diagnostic markers for lung cancer, the expression profiles of 37 lung tumours were analysed using cDNA arrays. Seven samples were from small-cell lung cancer (SCLC), two from large-cell neuroendocrine tumours (LCNEC), and 28 from other non-small-cell lung cancers (mainly squamous cell cancer and adenocarcinoma). Principal component analysis and the permutation test were used to detect differences in the gene expression profiles and a set of genes was found that distinguished high-grade neuroendocrine carcinomas (SCLC and LCNEC) from other lung cancers. In addition, several genes, such as caveolin-1 (CAV1) and caveolin-2 (CAV2), were constantly deregulated in all types of tumour sample, compared with normal tissue. The expression of these two genes was investigated further at the protein level on a tissue microarray containing tumours from 161 patients and normal tissues. Immunostaining for CAV1 was negative in 48% of tumours, whereas 28% of the tumours did not express CAV2. Lack of CAV1 protein expression was not caused by methylation or mutation. In stage I adenocarcinomas, CAV2 protein expression correlated with shorter survival. In conclusion, the present study was able to identify genes that have not previously been implicated in lung cancer by the combined use of two different array techniques. Some of these genes may provide novel diagnostic markers for lung cancer.  相似文献   
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We investigated the outcome of patients with antenatally detected pelviureteric junction (PUJ) obstruction treated either conservatively or surgically. The series comprised 68 such patients, 54 with unilateral obstruction. Of the unilateral cases, 22 units were treated conservatively, 21 underwent early and 11 late surgery. Of the bilateral cases, 18 units were treated conservatively, 9 underwent early pyeloplasty, whereas 1 underwent later surgery. Among the conservatively treated unilateral cases, none of the patients good renal function deteriorated during follow-up. In the group with early surgery, the primary good function remained unchanged in all. In some patients, moderate function improved after early pyeloplasty, but in patients with poor function no improvement occurred. Of patients who underwent late pyeloplasty, primary good renal function remained unchanged in all except 1, although it had deteriorated to moderate function in some before surgery. In all except 1 patient with bilateral obstruction treated conservatively, both the grade of hydronephrosis and split function remained unchanged. In most patients the outcome of antenatally detected unilateral PUJ obstruction with initially good renal function, whether treated conservatively or surgically, seems favorable. Some patients with moderate function might benefit from pyeloplasty. In kidneys with poor function, recovery may be minimal despite pyeloplasty.  相似文献   
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