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排序方式: 共有606条查询结果,搜索用时 15 毫秒
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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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Berenice Mathisen Sheena Reilly David Skuse 《Developmental medicine and child neurology》1992,34(2):141-149
The oral-motor function of 10 infants with Turner syndrome and their age- and sex-matched controls were assessed during feeding. In addition to well-recognised dysmorphic features, including oral anomalies and high-arched palates, index infants had marked hypotonia of the cheeks and lips, dysfunctional tongue movements and poorly developed chewing skills. Their meal-times were significantly shorter than those of the controls and they weighed significantly less at six, 12 and 15 months. All mothers of infants with Turner syndrome complained of difficulties feeding their children and these problems often had been present since birth. 相似文献
7.
Coralline hydroxyapatite bone graft substitutes: preliminary report of radiographic evaluation 总被引:1,自引:0,他引:1
A new bone graft substitute made by conversion of the calcium carbonate exoskeleton of reef-building sea coral into hydroxyapatite has recently become clinically available. The normal radiographic appearance of two forms of this material is described. In the immediate postoperative period, the exoskeletal architecture of these implants is readily appreciated. With graft incorporation over the ensuing months, their intrinsic structure is gradually lost in association with poor marginal definition. Evolving radiographic findings reflect the biocompatible nature of these implants, which provides the potential for ingrowth of native bone with preservation of the coralline scaffold, resulting in enhanced biomechanical properties. 相似文献
8.
A molecular and FISH analysis of structurally abnormal Y chromosomes in patients with Turner syndrome 总被引:3,自引:0,他引:3
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Robinson DO Dalton P Jacobs PA Mosse K Power MM Skuse DH Crolla JA 《Journal of medical genetics》1999,36(4):279-284
Fourteen patients with Turner syndrome and a structurally abnormal Y chromosome were analysed by PCR amplification and fluorescence in situ hybridisation for the presence of sequences specific to defined regions of the Y chromosome. Thirteen patients had a mosaic karyotype including a 45,X cell line and one case was non-mosaic in cultured lymphocytes. Ten patients had a pseudodicentric Yp chromosome, two an isodicentric Yq, one a pseudodicentric Yq, and one a derived Y chromosome. Two of the patients with a psu dic(Yp) chromosome had complex karyotypes with more than two cell lines, one of which exhibited five morphologically distinct mar(Y) chromosomes, presumably derived from a progenitor psu dic(Yp). Nine of the ten psu dic(Yp) chromosomes were positive for all Yp and Yq probes used except DYZ1 which maps to Yq12, suggesting a common breakpoint near the Yq euchromatin/heterochromatin boundary. In the three patients with a dicentric Yq chromosome two different breakpoints were observed; in two it was between PABY and the subtelomeric repeat sequence and in one it was between DYZ5 and AMGY in proximal Yp. Our results suggest that the great majority of structurally abnormal Y chromosomes found in Turner syndrome mosaics contain two copies of virtually all of the functional Y chromosome euchromatin. 相似文献
9.
Neurofibromatosis 2 (NF2) is an inherited cancer syndrome resulting from
mutations in the NF2 tumor suppressor gene. Analysis of NF2 mutations has
revealed some general genotype-phenotype correlations. Severe disease has
been associated with mutations that produce a premature termination while
more mild disease has been associated with missense mutations. Here, we
provide experimental proof for these genotype-phenotype correlations by
demonstrating that nonsense mutations fail to produce stable merlin protein
while missense mutations result in the generation of merlin proteins
defective in negative growth regulation. This inability to suppress cell
growth may result from defects in the function of merlin at several levels,
including failure to form an intramolecular complex. Based on these
findings, we propose a model for merlin growth suppression that provides a
framework for analyzing NF2 patient mutations and merlin function.
相似文献
10.
Induction of B cell apoptosis by co-cross-linking CD23 and sIg involves aberrant regulation of c-myc and is inhibited by bcl-2 总被引:2,自引:0,他引:2
Campbell KA; Studer EJ; Kilmon MA; Lees A; Finkelman F; Conrad DH 《International immunology》1997,9(8):1131-1140
A novel system to study the effects of co-cross-linking CD23/FceRII and sIg
on murine B lymphocytes utilizes a highly multivalent form of anti- Ig
prepared by covalently linking anti-Ig antibodies to a DNP-dextran
backbone. CD23-sIg co-cross-linking is accomplished by the addition of
DNP-specific monoclonal IgE. Previous studies demonstrated that co-
cross-linking CD23 and sIg significantly inhibited mouse B cell
proliferation, especially at high doses of the multivalent anti-Ig.
Interestingly, examination of early activation signals reveals no
difference in B cells subjected to co-cross-linking conditions as compared
to B cells activated with anti-Ig alone. Total cellular protein tyrosine
phosphorylation levels are unchanged by co-cross- linking. Analysis of B
cell mRNA reveals that co-cross-linking the receptors does not alter the
expression levels of ornithine decarboxylase 8 h after stimulation as
compared to the controls. In contrast, levels of the proto-oncogene c-myc
were significantly elevated 1 h after inducing B cell activation under
co-cross-linking conditions. However, it remains unclear whether this
aberrant c-myc regulation plays any role in inducing apoptosis. In
addition, on day 3 after stimulation, the co-cross-linking of CD23 and sIg
resulted in the formation of apoptotic B cells, determined by both
photomicroscopy of the B cell cultures and FACS analysis of B cell nuclei.
B cells obtained from bcl-2 transgenic mice proliferated as well as
controls, and failed to undergo apoptosis when CD23 and sIg were
co-cross-linked on their surface. These studies indicate that
co-cross-linking of CD23 with B cell sIg inhibits B cell proliferation by a
mechanism that is distinct from that seen by co-cross-linking of the Fc
gamma RII and sIg. In addition, these results suggest a means by which
antigen- specific IgE can down-regulate additional B cell activation and
IgE synthesis.
相似文献