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排序方式: 共有518条查询结果,搜索用时 15 毫秒
1.
Intratemporal vascular tumors: detection with CT and MR imaging 总被引:1,自引:0,他引:1
Lo WW; Shelton C; Waluch V; Solti-Bohman LG; Carberry JN; Brackmann DE; Wade CT 《Radiology》1989,171(2):445-448
The diagnostic contributions of computed tomography (CT) and magnetic resonance (MR) imaging were compared in 12 patients with benign intratemporal vascular tumors (hemangioma or vascular malformation). The tumors included six in the internal acoustic canal and six in the geniculate ganglion region. Clinical and histologic correlations were made. Two of the six patients with tumors in the internal acoustic canal underwent CT, and both required gas cisternography to show the tumor. Five patients in that group underwent MR imaging, and all five studies showed the tumor. All six patients with geniculate ganglion tumors underwent CT. Results in one study were questionable, and five showed the tumor. Five patients in this group underwent MR imaging, but the MR findings were positive in only two cases. MR imaging should therefore be performed before CT in the evaluation of facial nerve dysfunction, as it demonstrated all tumors in the internal acoustic canal and some in the geniculate ganglion region. If MR findings are negative, CT should then be performed to rule out a possible geniculate ganglion lesion. 相似文献
2.
K.A. Eaton F.M. Rimini E. Zak D.J. Brookman L.M.A. Hopkins P. J. Carmell LG. Yates C. A. Morrice B.A. Lall H. N. Newman 《Journal of clinical periodontology》1997,24(3):189-197
Abstract Several previous studies have evaluated the effects of 0.12% chlorhexidine digluconate (ChD) mouthrinses on plaque and gingival inflammation. However, previously, none have been based in general dental practices. The aim of this study was to evaluate the potential to conduct controlled periodontal clinical trials in co-operation with general dental practitioners (gdps). The project took place in 5 general dental practices in the South of England. 121 healthy subjects (24 at 4 sites and 25 at the 5th). aged 18-65 years, mean 35 ± 12) years participated in a double-blind, randomised study during which they received full mouth assessments for plaque and gingival bleeding at baseline, 6 and 12 weeks. 60 subjects were randomly asigned to use the 0.12% ChD mouth wash and 6i the placebo. The assessments were carried out by 5 gpds, who had previously achieved inter-examiner κ scores of 0.78–0.85 (mean 0.81) for the plaque index (PlI), and of 0.73–0.94 (mean 0.87) for a modified gingival index (mGI), and who maintained κ scores of 0.51–0.90 for PII and of 0.73–1.00 for mGI during the 12 months required to complete the study. 98 subjects (48 ChD and 50 placebo) completed the study. Even though the baseline levels of plaque and gingivitis were low, by week 12, mean whole mouth piaque score of the ChD mouthwash users had fallen from 1.33 at baseline to 0.96 and was significantly lower (p < 0.001) than for the placebo users, 1.31 at baseline to 1.13. Whole-mouth gingival bleeding score fell from 0.56 to 0.42 in the ChD mouthwash group but was unchanged (0.54–0.55) in the placebo group. A subsidiary data analysis which considered the effects at sites indicated that within these overall differences, the ChD users experienced almost 2× the reduction from plaque score 2 at baseline at proximal molar sites over a 12-week period (50.6% ChD versus 27.6% placebo). It was concluded that 0.12% ChD mouthwash reduced plaque accumulation fay 28% and gingival inflammation by 25% over a 12–week period, that it is feasible for a group of gdps to maintain high levels of inter–examiner consistency in the use of PlI and mGI, that it is also feasible to carry out such a multicentre study in general dental practice, and that the use of mean mouth scores per subject to analyse the effects of mouthrinses may well mask variations in response throughout the mouth. 相似文献
3.
LG Dortmund 《MedR Medizinrecht》2007,25(8):493-494
Abstrakt Vergibt ein behandelnder Arzt eine Laboruntersuchung an einen externen Laborarzt, kommt entweder direkt ein Vertragsverh?ltnis
zwischen dem Laborarzt und dem Patienten zustande oder der Patient haftet dem Laborarzt aus den Grunds?tzen der Gesch?ftsführung
ohne Auftrag. 相似文献
4.
5.
L Lundgren L G Kindblom T Seidal L Angervall 《APMIS : acta pathologica, microbiologica, et immunologica Scandinavica》1991,99(9):820-828
The expression of fine and intermediate cytofilaments in 10 cutaneous and seven subcutaneous leiomyosarcomas was studied immunohistochemically. All the tumors contained tumor cells which showed a positive immunoreactivity for desmin in formaldehyde-fixed and paraffin-embedded sections, but none of the seven anti-desmin antibodies used alone produced a distinct positive staining in all the tumors. A lack of correspondence in terms of immunoreactivity between tumor cells and the supposed muscle of origin was observed, especially in the subcutaneous leiomyosarcomas. In all cases, antibodies to muscle-specific and smooth muscle-specific actin were found to produce a positive staining in both the tumors and the supposed muscle of origin. Vimentin was detected in 8/10 cutaneous and 4/7 subcutaneous leiomyosarcomas, while the supposed muscle of origin was positive in 3/10 and 7/7 cases, respectively. Four of the cutaneous and three of the subcutaneous leiomyosarcomas contained tumor cells which stained positively for cytokeratins, while the supposed muscle of origin showed no positivity. It thus appears that a phenotypic shift in terms of vimentin and cytokeratin expression occurs in the tumor cells of cutaneous and subcutaneous leiomyosarcomas compared with the supposed muscle of origin. It is recommended that more than one monoclonal anti-desmin antibody is used to characterize these tumor entities. It is also concluded that the immunoreactivity for muscle-specific actins in superficial leiomyosarcomas is more constant, although less specific, than that of desmin and that the demonstration of the simultaneous expression of muscle-specific actins and desmin is helpful. 相似文献
6.
Periosteal Ewing sarcoma 总被引:3,自引:0,他引:3
7.
The Charcot-Mane-Tooth disease type 1A (CMTlA) phenotype is most often associated with a 1.5 megabase (mb), tandem duplication of chromosome 17 band p12 (17˜12). The prevailing hypothesis is that the demyelinating neuropathy results from a dosage effect of the peripheral myelin protein gene PMP22 which is included within this duplication. We present a patient with clinical and electrophysiological features ofCMTlA in whom an extra PMP22 gene resulted from a rare unbalanced translocation of 17p to the X chromosome. This finding further supports the hypothesis of gene dosage as the basis for CMTlA. More-over, this case highlights the importance of fluorescence in siiu hybridization (FISH) as an alternative molecular technique in the diagnosis of CMTlA. 相似文献
8.
9.
Clearcell sarcoma is a rare soft tissue sarcoma that displays certain similarities to malignant melanoma. In this paper we describe the karyotypic findings and in vitro growth characteristics of a shorttermcultured clearcell sarcoma. The cultured tumor cells had preserved immunohistochemical characteristics and certain ultrastructural features of the primary tumor, including positivity for vimentin, S-100 protein, and a melanomaassociated antigen, supporting the authenticity of the cultured cells. Cytogenetic analysis revealed an abnormal stemline karyotype of 49,XY, –1, + 8, + 8, + 12, + der(l)t(1;?)(p36.1 –.3;?), t(12,22)(q13;q13). A similar or identical t(12;22) was recently reported in two of four clear-cell sarcomas. It is suggested that the t(12;22)(q13;q13) is a primary cytogenetic abnormality in clear-cell sarcoma and distinguishes this tumor type from malignant melanoma. 相似文献
10.
Y chromosome deletions in azoospermic and severely oligozoospermic men undergoing intracytoplasmic sperm injection after testicular sperm extraction 总被引:11,自引:16,他引:11
Silber SJ; Alagappan R; Brown LG; Page DC 《Human reproduction (Oxford, England)》1998,13(12):3332-3337
Y chromosome deletions encompassing the AZFc region have been reported in
13% of azoospermic men and 7% of severely oligozoospermic men. We examined
the impact of these Y deletions on the severity of testicular defects in 51
azoospermic men undergoing intracytoplasmic sperm injection (ICSI) after
testicular sperm extraction (TESE) and 30 men with severe oligozoospermia
undergoing ICSI after ejaculation of spermatozoa. In addition, five
azoospermic patients shown previously to have Y chromosome deletions
underwent histological evaluation of their previously obtained testis
biopsy specimens. A further 27 azoospermic men underwent TESE-ICSI, but not
Y chromosome DNA testing. Ten of 51 azoospermic men (20%) who underwent
TESE-ICSI and Y-DNA testing were found to be deleted for portions of the Y
chromosome AZFc region. Of these 10, five had spermatozoa retrievable from
the testis, and in two cases the wives became pregnant. Of the 41
azoospermic men with no Y chromosome deletion, 22 (54%) had spermatozoa
retrievable from the testis, and in 12 cases (29%) the wives became
pregnant. Four of 30 (13%) severely oligozoospermic patients were found to
be deleted for AZFc and in three (75%) of these pregnancy was achieved. The
other 26 severely oligozoospermic couples who had no AZFc deletions
underwent ICSI, and 12 (46%) have an ongoing or delivered pregnancy. The
embryo implantation rate was not significantly different for azoospermic
(22%), oligozoospermic (16%), Y-deleted (14%) or Y-intact (18%) men. Of the
total of 19 infertile men who had Y chromosome deletions, 14 had deletions
within Y chromosome intervals 6D-6F, in the AZFc region. Twelve of those 14
had some spermatozoa (however few in number) in the ejaculate or testis.
Five of the Y-deleted men had deletions that extended more proximally on
the Y chromosome, and in none of these could any spermatozoa be observed in
either ejaculate or testis. These results support the concept that, in
azoospermic or oligozoospermic men with Y chromosome deletions limited to
intervals 6D-6F (AZFc), there are generally very small numbers of
testicular or ejaculated spermatozoa. Larger Y deletions, including and
extending beyond the AZFc region and encompassing more Y genes, tend to be
associated with a total absence of testicular spermatozoa. In those cases
where spermatozoa were retrieved, the presence of Y deletions had no
obvious impact on fertilization or pregnancy rate.
相似文献