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排序方式: 共有850条查询结果,搜索用时 15 毫秒
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Acute appendicitis: CT and US correlation in 100 patients 总被引:19,自引:1,他引:18
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Perforated colorectal neoplasms: correlation of clinical, contrast enema, and CT examinations 总被引:2,自引:0,他引:2
Hulnick DH; Megibow AJ; Balthazar EJ; Gordon RB; Surapenini R; Bosniak MA 《Radiology》1987,164(3):611-615
Results of clinical, contrast enema (CE), and computed tomographic (CT) examinations in 39 patients with perforated colorectal neoplasms were retrospectively reviewed. Twenty patients were toxemic at initial presentation, but in only four patients was the diagnosis of perforated colorectal neoplasm initially suspected clinically. CE study was performed in 22 patients and enabled the diagnosis of perforated neoplasm in 11 cases, neoplasm alone in eight, and neither neoplasm nor perforation in three. CT was performed in 38 patients and enabled the diagnosis of perforated neoplasm in 36; pericolic phlegmon but no mass lesion was evident in two. In 16 patients, CT also demonstrated metastatic disease. Because of its reliability in establishing the diagnosis and staging the extent of the inflammatory and neoplastic disease, CT is indicated in cases of suspected or proved perforated colorectal neoplasm and in cases in which CE study findings are indeterminate or suggestive of perforated neoplasm. 相似文献
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Steenbergen EJ; Verhagen OJ; van Leeuwen EF; van den Berg H; von dem Borne AE; van der Schoot CE 《Blood》1995,86(2):692-702
Crosslineage T-cell receptor delta (TCR delta) rearrangements are widely used as tumor markers for the follow up of minimal residual disease in childhood B-precursor acute lymphoblastic leukemia (ALL) by polymerase chain reaction (PCR). The major drawback of this approach is the risk of false-negative results due to clonal evolution. We investigated the stability of V delta 2D delta 3 rearrangements in a group of 56 childhood B-precursor ALL patients by PCR and Southern blot analysis. At the PCR level, V delta 2D delta 3-to-J alpha rearranged subclones (one pathway for secondary TCR delta recombination) were demonstrated in 85.2% of V delta 2D delta 3-positive patients tested, which showed that small subclones are present in the large majority of patients despite apparently monoclonal TCR delta Southern blot patterns. Sequence analysis of V delta 2D delta 3J alpha rearrangements showed a biased J alpha gene usage, with HAPO5 and J alpha F in 26 of 32 and 6 of 32 clones, respectively. Comparison of V delta 2D delta 3 rearrangement status between diagnosis and first relapse showed differences in seven of eight patients studied. In contrast, from first relapse onward, no clonal changes were observed in six patients studied. To investigate the occurrence of crosslineage TCR delta rearrangements in normal B and T cells, fluorescence-activated cell sorter-sorted peripheral blood CD19+/CD3- and CD19-/CD3+ cell populations from three healthy donors were analyzed. V delta 2D delta 3 rearrangements were detected at low frequencies in both B and T cells, which suggests that V delta 2-to-D delta 3 joining also occurs during normal B-cell differentiation. A model for crosslineage TCR delta rearrangements in B-precursor ALL is deduced that explains the observed clonal changes between diagnosis and relapse and is compatible with multistep leukemogenesis of B-precursor ALL. 相似文献
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Mulders AG Laven JS Eijkemans MJ de Jong FH Themmen AP Fauser BC 《Human reproduction (Oxford, England)》2004,19(9):2036-2042
BACKGROUND: Anti-Müllerian hormone (AMH), produced by growing pre-antral and early antral ovarian follicles, has been shown to be a useful marker for ovarian ageing. Serum AMH concentrations are elevated during reproductive life in anovulatory women, especially in those patients exhibiting polycystic ovaries (PCO). The current study was designed to investigate whether the decrease in AMH serum concentrations over time is different comparing women with normogonadotrophic anovulation [World Health Organization (WHO) group 2 (including polycystic ovary syndrome (PCOS)] and normo-ovulatory controls. METHODS AND RESULTS: AMH serum levels were assessed on two occasions in 98 patients suffering from WHO 2 anovulatory infertility as well as in 41 normo-ovulatory premenopausal women. Median time interval between both visits was 2.6 years (range 0.3-9.0) for WHO 2 patients compared with 1.6 years (range 1.0-7.3) in controls. Serum AMH concentrations were significantly (P < 0.0001) elevated on both occasions in WHO 2 patients (AMH1, median = 7.5 microg/l, range 0.1-35.8; and AMH2, median = 6.7 microg/l, range 0.0-30.6) compared with controls (AMH1, median = 2.1 microg/l, range 0.1-7.4; and AMH2, median = 1.3 microg/l, range 0.0-5.0). Regression analysis, corrected for age, indicated a significant relative decrease in serum AMH concentrations over time for both groups (P < 0.001). However, the decline in serum AMH in WHO 2 patients was significantly less compared with controls (P = 0.03). CONCLUSION: The present longitudinal study shows that serum AMH concentrations decrease over time both in women presenting with WHO 2 anovulatory infertility and in normo-ovulatory controls. The decrease in WHO 2 patients is less pronounced despite distinctly elevated concentrations. This observation may suggest retarded ovarian ageing and hence a sustained reproductive life span in these patients. 相似文献
10.
Phylogenetic analysis of rhinovirus isolates collected during successive epidemic seasons 总被引:4,自引:0,他引:4
Human rhinoviruses (HRV) have been shown to be the major causative agent for mild respiratory infections, but also associated with more serious diseases, such as acute otitis media and pneumonia in children, and asthma. Despite the economical and medical importance of HRV, little is known about the circulation and genetic diversity of HRV during a given season. The aim of this study was to genetically characterize HRV strains causing acute respiratory infections in a cohort of small children during a 2 years follow-up time. Genetic relationships between 61 HRV field isolates were studied using partial genomic sequencing in the VP4/VP2 region (420 nt) and phylogenetic analysis of these sequences. Sequences from the clinical isolates clustered in the two previously known phylogenetic clades, the designated genetic group 2 (including HRV 14) being more predominant. The maximum genetic variation within group 1 was 32.3% and within group 2 it was 32.7%. Several distinct clusters could be observed, some of which were strictly seasonal, whereas some other variants were detected during several seasons. The results of this study show striking genetic diversity of the HRV strains circulating in a given community during a short time. 相似文献