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631.
632.
Stereotactic breast biopsy with a biopsy gun 总被引:37,自引:1,他引:36
Parker SH; Lovin JD; Jobe WE; Luethke JM; Hopper KD; Yakes WF; Burke BJ 《Radiology》1990,176(3):741-747
One hundred three patients underwent stereotactic breast biopsy with an 18-, 16-, or 14-gauge cutting needle and a biopsy gun. After biopsy, a localization wire was placed and surgical biopsy performed. There was agreement of the histologic results in 89 cases (87%) including 14 of 16 cancers (87%) (kappa = 0.806). The gun biopsy yielded the correct diagnosis in four cases involving a lesion (including one cancer) that was missed at the surgical biopsy. Nine cases in which the lesion was missed at gun biopsy can be related to insufficient needle size, the greater difficulty in using one of the two stereotactic devices, and early inexperience with the technique. A 14-gauge needle was used in the last 29 biopsies, the results of which agreed with the surgical pathologic findings in 28 cases (97%). With greater experience, stereotactic-guided large-gauge automated percutaneous biopsy may prove to be an acceptable alternative to surgical biopsy in women with breast masses suspected at mammography. 相似文献
633.
Human immunodeficiency virus-type 1 replication can be increased in peripheral blood of seropositive patients after influenza vaccination 总被引:18,自引:0,他引:18
O'Brien WA; Grovit-Ferbas K; Namazi A; Ovcak-Derzic S; Wang HJ; Park J; Yeramian C; Mao SH; Zack JA 《Blood》1995,86(3):1082-1089
Despite considerable evidence that cell activation enhances human immunodeficiency virus-type 1 (HIV-1) replication in vitro, there is very little data on the role of immune activation on in vivo HIV-1 replication. In this study, we examined the effect of influenza vaccination on HIV-1 replication in the peripheral blood of 20 study subjects, and in 14 control subjects who did not receive influenza vaccination. Blood was obtained from each subject on three occasions during the month before vaccination and again on three occasions during the following month. Over the study period, there was little change in levels of proviral DNA in peripheral blood mononuclear cells (PBMCs). However, peak PBMC viral RNA levels after influenza vaccination were significantly increased over the mean of prevaccination values. This change was not observed to the same extent in unvaccinated controls. Therefore, this is the first report showing that HIV-1 replication can increase in temporal association with influenza vaccination. Our results suggest that continued immunologic (antigenic) stimulation may result in increased virus load in vivo. To address the appropriateness of influenza vaccination in HIV-infected patients, expanded studies will be required to examine specific and generalized immune responses to vaccination, and differences in patient response based on disease stage. 相似文献
634.
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636.
A 3-yr-old boy presented with a monoarthritis. Persistence of the condition
and some unusual features led to re-evaluation of the original
investigations, when a diagnosis of extensive plexiform neurofibroma
involving his right leg was made. This previously unreported presentation
of neurofibromatosis is discussed.
相似文献
637.
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639.
Johnsen NM; Schwarze PE; Nyholm SH; Lag M; Becher R; Brunborg G; Holme JA 《Carcinogenesis》1997,18(1):193-199
The genotoxic effects of the environmental contaminants
benz[j]aceanthrylene (B[j]A), benz[l]aceanthrylene (B[l]A) and
benzo[a]pyrene (B[a]P), and the metabolism of radiolabelled B[j]A, were
studied using rat lung microsomes and various types of isolated rat lung
cells from control and Aroclor 1254 (PCB) treated animals. All three
compounds (10 or 20 microg/plate) resulted in low, but detectable, levels
of His+ revertants in the Salmonella assay when plated with control lung
microsomes. The two cyclopenta polycyclic aromatic hydrocarbons (CP-PAH)
B[j]A and B[l]A, gave increased levels of revertants when plated with
microsomes from PCB-treated animals. Clara cells, type 2 cells and alveolar
macrophages isolated from control rats were exposed to B[j]A, B[l]A or
B[a]P (30 microg/ml, 1 h), but neither of the cell types showed any DNA
damage when measured by alkaline filter elution. However, both B[j]A and
B[l]A (30 microg/ml, 2 h) caused DNA adducts in all three cell types,
measured by the 32P-post- labelling technique, whereas no B[a]P adducts
were detected (30 microg/ml, 2 h). The total DNA adduct levels in Clara
cells, type 2 cells and macrophages exposed to B[j]A were 0.085 +/- 0.033,
0.053 +/- 0.001 and 0.170 +/- 0.030 fmol/microg DNA, respectively, whereas
the total levels in cells exposed to B[l]A were 0.140 +/- 0.070, 0.140 +/-
0.030 and 0.220 +/- 0.080 fmol/microg DNA, respectively. Cells exposed to
B[j]A revealed only one adduct which corresponds with the B[j]A-1,2- oxide
DNA adduct. Judged from high performance liquid chromatography (HPLC)
analysis using radiolabelled B[j]A (30 microg/ml, 30 min), the major
metabolite formed in control microsomes was B[j]A-1,2-diol. Thus, oxidation
at the cyclopenta ring appears to be the most important activation pathway
for B[j]A with control rat lung cells. Exposure of lung cells to CP-PAH (30
microg/ml, 2 h) isolated from PCB pretreated rats resulted in slightly
increased DNA adduct levels in Clara cells and macrophages when compared to
cells isolated from control rats. Furthermore, the adduct pattern had
shifted, and no apparent B[j]A-1,2- oxide adduct could be detected on the
thin layer chromatography (TLC) plate. In contrast, the major metabolite
formed with microsomes from PCB-treated animals was still the
B[j]A-1,2-diol.
相似文献
640.
Characterisation of renal chloride channel, CLCN5, mutations in hypercalciuric nephrolithiasis (kidney stones) disorders 总被引:4,自引:0,他引:4
Lloyd SE; Gunther W; Pearce SH; Thomson A; Bianchi ML; Bosio M; Craig IW; Fisher SE; Scheinman SJ; Wrong O; Jentsch TJ; Thakker RV 《Human molecular genetics》1997,6(8):1233-1239
Mutations of the renal-specific chloride channel (CLCN5) gene, which is
located on chromosome Xp11.22, are associated with hypercalciuric
nephrolithiasis (kidney stones) in the Northern European and Japanese
populations. CLCN5 encodes a 746 amino acid channel (CLC-5) that has
approximately 12 transmembrane domains, and heterologous expression of
wild-type CLC-5 in Xenopus oocytes has yielded outwardly rectifying
chloride currents that were markedly reduced or abolished by these
mutations. In order to assess further the structural and functional
relationships of this recently cloned chloride channel, additional CLCN5
mutations have been identified in five unrelated families with this
disorder. Three of these mutations were missense (G57V, G512R and E527D),
one was a nonsense (R648Stop) and one was an insertion (30:H insertion). In
addition, two of the mutations (30:H insertion and E527D) were demonstrated
to be de novo, and the G57V and E527D mutations were identified in families
of Afro-American and Indian origin, respectively. The G57V and 30:H
insertion mutations represent the first CLCN5 mutations to be identified in
the N-terminus region, and the R648Stop mutation, which has been observed
previously in an unrelated family, suggests that this codon may be
particularly prone to mutations. Heterologous expression of the mutations
resulted in a marked reduction or abolition of the chloride currents,
thereby establishing their functional importance. These results help to
elucidate further the structure-function relationships of this renal
chloride channel.
相似文献