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61.
Cytogenetic analysis by short-term culture of a lipoma from the posterior neck region of a 63-year-old man showed a t(X;12)(q27;q14) as the sole chromosomal abnormality. Rearrangement of band 12q14 is nonrandom in lipomas, although its involvement with a sex chromosome has not been reported earlier. 相似文献
62.
Iréne?LundEmail author Thomas?Lundeberg Louise?Sandberg Cecilia?Norrbrink?Budh Jan?Kowalski Elisabeth?Svensson 《BMC medical research methodology》2005,5(1):31
Background:
Rating scales like the visual analogue scale, VAS, and the verbal rating scale, VRS, are often used for pain assessments both in clinical work and in research, despite the lack of a gold standard. Interchangeability of recorded pain intensity captured in the two scales has been discussed earlier, but not in conjunction with taking the influence of pain etiology into consideration. 相似文献63.
The sister chromatid exchange (SCE) incidence and growth kinetics have been studied by means of an in vitro bromodeoxyuridine (BrdU) chromosome labeling method in the bone marrow cells of 17 acute myeloblastic leukemia (AML) patients with only diploid cells at diagnosis, remission, and relapse of the disease. At diagnosis, the cells tended to exhibit a low SCE frequency as compared to that during remission. An increased SCE frequency was observed after chemotherapy during remission or relapse. At diagnosis and relapse, when leukemic blast cells predominated in the marrow, they were characterized by the predominance of cells that had undergone only one cell cycle after BrdU exposure. In contrast, the marrow cells during remission tended to resemble the control pattern of growth kinetics, with a predominance of cells undergoing second and third cell cycles in the presence of BrdU. These results suggest that the growth rate of leukemic and nonleukemic cells is different, and that chemotherapy can cause an increased SCE frequency in the marrow cells of AML patients irrespective of the state of the disease. 相似文献
64.
Tsai JC de Groot L Pinon JD Iacono KT Phillips JJ Seo SH Lavi E Weiss SR 《Virology》2003,312(2):369-380
Targeted recombination was carried out to select mouse hepatitis viruses (MHVs) in a defined genetic background, containing an MHV-JHM spike gene encoding either three heptad repeat 1 (HR1) substitutions (Q1067H, Q1094H, and L1114R) or L1114R alone. The recombinant virus, which expresses spike with the three substitutions, was nonfusogenic at neutral pH. Its replication was significantly inhibited by lysosomotropic agents, and it was highly neuroattenuated in vivo. In contrast, the recombinant expressing spike with L1114R alone mediated cell-to-cell fusion at neutral pH and replicated efficiently despite the presence of lysosomotropic agents; however, it still caused only subclinical morbidity and no mortality in animals. Thus, both recombinant viruses were highly attenuated and expressed viral antigen which was restricted to the olfactory bulbs and was markedly absent from other regions of the brains at 5 days postinfection. These data demonstrate that amino acid substitutions, in particular L1114R, within HR1 of the JHM spike reduced the ability of MHV to spread in the central nervous system. Furthermore, the requirements for low pH for fusion and viral entry are not prerequisites for the highly attenuated phenotype. 相似文献
65.
We report the detailed cytogenetic findings from short-term cultures of six lipomas with complex chromosomal abnormalities. In all six cases, the abnormality occurred in two stages; an initial inversion, translocation, or insertion of the involved chromosome(s) followed by a subsequent rearrangement of the resultant derivative chromosome(s). A striking feature of these rearrangements was the consistent involvement of bands q13 - q14 on chromosome 12 in all the abnormalities. This region has been shown to be specifically rearranged in most of the lipomas studied. The other chromosomes involved in the rearrangements were chromosomes 1 in four cases, 5 and 9 in two cases each, and 2, 3, 4, 7, and 10 in one case each. Our findings and published findings show that, with a few exceptions, benign tumors that were previously considered cytogenetically normal, are characterized not only by specific numerical and structural changes but may also contain complex chromosome rearrangements that are generally considered a hallmark of advanced malignancy. In benign tumors, this suggests that the genes at the region of the breakpoints may represent proliferation-related genes or that benign tumors with such complex aberrations represent neoplasms potentially capable of undergoing transformation to malignancy, or both. 相似文献
66.
Detecting Candida albicans in human milk 总被引:1,自引:0,他引:1
Morrill JF Pappagianis D Heinig MJ Lönnerdal B Dewey KG 《Journal of clinical microbiology》2003,41(1):475-478
Procedures for diagnosis of mammary candidosis, including laboratory confirmation, are not well defined. Lactoferrin present in human milk can inhibit growth of Candida albicans, thereby limiting the ability to detect yeast infections. The inhibitory effect of various lactoferrin concentrations on the growth of C. albicans in whole human milk was studied. The addition of iron to the milk led to a two- to threefold increase in cell counts when milk contained 3.0 mg of lactoferrin/ml and markedly reduced the likelihood of false-negative culture results. This method may provide the necessary objective support needed for diagnosis of mammary candidosis. 相似文献
67.
Michelle Bonnett Tracie Wallis Michelle Rossmann Nat L Pernick David Bouwman Kathryn A Carolin Daniel Visscher 《Modern pathology》2003,16(2):154-160
Appropriate follow-up of patients with needle core breast biopsies (NCBB) showing atypical hyperplasia remains unclear because previous studies show that subsequent open biopsies in variable proportions of these patients reveal ductal carcinoma in situ (DCIS) or even invasive carcinoma, indicating significant sampling artifact. NCBB with diagnoses of atypia were morphologically classified into groups as follows: I, ALH (n = 24); II, ADH with minimal cytologic atypism (n = 90); III, atypia, other (9 columnar, 2 apocrine, 11 atypical papillary); IV, severe ADH/borderline DCIS (n = 31). Mammographic and histologic features, including the number of foci of atypia in the NCBB and the calcification span, were then correlated with presence of DCIS or invasive tumor in subsequent open excisions. Open excisional biopsies showed more severe lesions in 12% of Group I-III cases (8% in Group I, 9% in Group II, and 27% in Group III), of which 15 were DCIS and one was an invasive tubular carcinoma (0.3 cm). Of the DCIS, 60% (n = 9) were < or =5 mm, and 13 of 15 (87%) were low grade. The NCBB cavity was immediately adjacent to the more severe lesions in 88% (n = 14) of cases, in keeping with sampling error. The subset showing severe ADH with borderline nuclear features in contrast was associated with a high likelihood (63%) of DCIS in follow-up excisions. NCBB with atypical papillary features also showed a high frequency of DCIS (4/11, 36%) in subsequent open excisions. Other factors associated with more severe lesions on open biopsy included the number of atypical foci in the NCBB (>4, P <.05) and the mammographic calcification span (>2.0 cm, P <.0001). Atypical lesions diagnosed in NCBB samples are radiographically and morphologically heterogeneous, accounting for the variable frequency of DCIS or invasive neoplasm identified in subsequent open excisions, which are usually focal, low grade, and a consequence of sampling artifact (i.e., adjacent to the NCBB cavity). DCIS is more likely if microcalcifications are mammographically extensive or if atypia is multifocal or is associated with borderline cytologic features. 相似文献
68.
69.
J Limon Z Gibas M Babinska B Beil A Bomirski P Mierzewski A A Sandberg 《Cancer Genetics and Cytogenetics》1987,25(1):123-129
The chromosome constitutions of black-melanotic (Ma), brown-melanotic (MI), and amelanotic (Ab) melanomas of the Syrian hamster were compared. The MI and Ab melanomas arose through a spontaneous phenotypic alteration of the Ma tumor. All three variants differ in their growth rates, with MI showing the slowest, Ab the fastest, and Ma intermediate growth rate. Cytogenetic examination revealed that each tumor line shows a distinct karyotype. The Ma tumor is near-diploid, whereas, Ab and MI tumors are hypertriploid and near-tetraploid, respectively. Each tumor line shows a unique set of marker chromosomes, though some markers are shared by two different tumor lines. No single marker chromosome was common for all three melanoma variants. We conclude that the spontaneous phenotypic variation of transplantable hamster melanomas is associated with profound changes in the chromosome constitution of the neoplastic cells. The general direction of these changes is toward increased ploidy and increased complexity of the structural abnormalities. 相似文献
70.
H Yamanaka R Y Kirdani J Saroff G P Murphy A A Sandberg 《The American journal of physiology》1975,229(4):1102-1109
Prostatic weights, 5alpha-reductase, and arginase activities were utilized as indexes for the effects of prolactin in short-term experiments in intact, hypophysectomized or castrated rats. Experiments were performed in which a dose-related response in the above parameters was obtained with testosterone administration in castrated mature and immature rats in order to evaluate the effects of simultaneously administered prolactin. This approach was necessitated by the failure of prolactin alone to affect the parameters listed in intact, castrated or hypophysectomized rats. It was shown that ovine prolactin may have an enhancing effect on the prostatic weight, 5alpha-reductase, and arginase activities, but that this effect is neither consistent nor striking when compared to that of testosterone.. Nevertheless, it is still possible that the long-term effects of prolactin, even if they are only of an enhancing quality, may play an important role in normal prostatic physiology and in abnormal states. 相似文献