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81.
目的 :探讨细胞周期调控蛋白 P2 1CIP1 / WAF1 和细胞粘附分子 CD44 V6 在恶性卵巢上皮性肿瘤中的增殖、浸润、转移过程中的作用及相互关系。方法 :采用免疫组化方法 (im munohistochemical assay IHCA)检测 5 5例恶性卵巢上皮性肿瘤组织中 P2 1CIP1 / WAF1 蛋白和 CD44 V6 的表达。结果 :(1)恶性卵巢上皮性肿瘤中 P2 1CIP1 / WAF1总体阳性率为 5 5 .5 4% ,其中 期的阳性率为 2 1.43%低于 至 期的阳性率 6 5 .85 % (P<0 .0 5 ) ,伴有淋巴结转移的原发灶中的阳性率 31.5 7%明显低于无淋巴结转移的原发灶中的阳性率 6 6 .6 7% (P<0 .0 5 )。 (2 ) CD44 V6 在 到 期癌组织中表达阳性率差别无显著性 (P>0 .0 5 ) ,而在 、 期中强阳性 ( 、 )率 5 3.13%明显高于 、 期 13.0 4%(P<0 .0 5 ) ,在有淋巴结转移的原发灶中的强阳性率 (6 8.42 % )高于无淋巴结转移组 19.44 % (P<0 .0 1)。 (3) P2 1CIP1/ WAF1与 CD44 V6 在有淋巴结转移的原发灶中的表达呈负相关 (P<0 .0 5 )。结论 :P2 1CIP1 / WAF1 抑制恶性卵巢上皮性肿瘤增殖、浸润、转移 ,而 CD44 V6 作用相反 相似文献
82.
Gregory McCarthy Mark Spicer Anthony Adrignolo Marie Luby John Gore Truett Allison 《Human brain mapping》1994,2(4):234-243
Localized brain activation in response to moving visual stimuli was studied by functional magnetic resonance imaging (fMRI). Stimuli were 100 small white dots randomly arranged on a visual display. During the Motion condition, the dots moved along random, noncoherent linear trajectories at different velocities. During the Blink condition, the dots remained stationary but blinked on and off every 500 ms. The Motion and Blink conditions continuously alternated with 10 cycles per run and 6–8 runs per experiment. In half of the runs, the starting stimulus condition was Motion, while in the remaining runs it was Blink. A series of 128 gradient echo echoplanar images were acquired from 5–7 slices during each run using a 1.5 T GE Signa with an Advanced NMR echoplanar subsystem. The time series for each voxel were analyzed in the frequency domain. Voxels which demonstrated a significant spectral peak at the alternation frequency and whose phase changed in response to stimulus order were considered activated. These activated voxels were displayed upon high resolution anatomical images to determine the sites of activation and were also transformed into the coordinates of Talairach and Tournoux ([1988] Co-planar Stereotaxic Atlas of the Human Brain, New York: Thieme) for comparison to prior neuroimaging studies. Seven of ten subjects showed clusters of activation bilaterally at the junction of the temporal and occipital lobes (area 37) in response to moving stimuli. Most activated voxels were located within or adjacent to a region designated the parietal-temporal-occipital fossa, or PTOF. Five subjects also showed activation to moving stimuli in midline occipital cortex. The activated voxels in midline cortex had a significantly shorter phase delay in their MR signal change relative to voxels in PTOF. © 1995 Wiley-Liss, Inc. 1 1 This article is a US Government work and, as such, is in the public domain in the United States of America 相似文献
83.
目的:研究胃癌CD44V6的表达与肿瘤浸润、淋巴结转移的关系。方法:应用CD44V6单克隆抗体,用S-P法免疫组织化学技术进行观察。结果:70例胃癌中24例(34.3%)CD44V6阳性。淋巴结转移组CD44V6阳性率45.7%明显高于无转移组的12.5%(X^2=11.24,P〈0.01);结论:提示CD44V6的表达可作为预测胃癌转移的较好指标。 相似文献
84.
为评价部分平均通过时间(MTTp)和F-V曲线形状对检查吸烟者小气道功能的临床意义,作者对116例被动和轻、重度主动吸烟者进行了常规肺通气功能、MTTp和F-V曲线形状的探讨。常规肺通气功能和F-V曲线形状用常规法测定。MTTp用“简易计算法”公式计算。结果显示凸型F-V曲线的分布随吸烟程度而上升。·V50、·V25下降及MTT45%~55%、MTT70%~80%延长在凸型与重度吸烟组一致。MTT45%~55%与MTT70%~80%延长的范围在两者都是预计值的110%~120%,表明小气道功能已有轻度障碍。因而凸型F-V曲线、MTT45%~55%及MTT70%~80%延长、·V50、·V25下降都是检查小气道功能的敏感指标。用“简易计算法”计算MTTp简便准确,宜于临床推广应用 相似文献
85.
Objective
Retrograde intubation of canaliculi during dacryocystorhinostomy can restore canalicular patency in cases otherwise managed with bypass tubes. The surgical technique and success for this procedure are discussed.Design
A retrospective, noncomparative case series with clinic or telephone interview for long-term follow-up of patients’ symptoms.Participants
One hundred two patients who had undergone this particular lacrimal drainage surgery at Moorfields Eye Hospital between 1992 and 1997.Intervention
All patients underwent a dacryocystorhinostomy and retrograde canaliculostomy while under general anesthetic.Main outcome measures
Relief or reduction of epiphora and discharge.Results
One hundred twenty-three lacrimal systems of 102 patients were included. There were 53 females and 49 males, with ages at surgery ranging from 6 to 83 years (mean, 49 years). The etiology was idiopathic (30%), herpetic canaliculitis (24%), punctal agenesis (18%), and trauma (11%); less-common causes included dacryocystitis, Stevens-Johnson syndrome, eczema, and prior radiation therapy. Both upper and lower canalicular systems were involved in the majority (73%) of patients, and in 13 (11%) systems a dacryocystorhinostomy had previously been performed. The silicone tube was placed for a mean of 2 months (range, 1 week–9 months), and the mean postoperative follow-up was 8 months (range, 2–24 months). Epiphora subjectively improved in 90 (73%) of 123 systems, of which 27 (22%) of 123 were asymptomatic. In 33 systems (27%) in which epiphora persisted, 14 (11%) have undergone closed placement of a Jones canalicular bypass tube with control of symptoms.Conclusions
Retrograde canaliculostomy and intubation can spare a significant number of patients the long-term inconvenience of Jones tubes. Failure of this technique does not, however, compromise or complicate the future placement of a bypass tube. 相似文献86.
Maberley DA Yannuzzi LA Gitter K Singerman L Chew E Freund KB Noguiera F Sallas D Willson R Tillocco K 《Ophthalmology》1999,106(12):2248-52; discussion 2252-3
Objective
To examine the association between previous radiation exposure and idiopathic perifoveal telangiectasis (IPT).Design
A multicentered, individually matched, case-control study design was used.Participants/controls
Sixty-five case subjects were matched with 175 control subjects. Individuals with unequivocal evidence of angiographically confirmed IPT were included as cases. Control subjects were matched for center, age, and gender.Main outcome measure
The main exposures of interest were a history of therapeutic head or neck irradiation and environmental radiation exposure.Methods
A standardized questionnaire was administered to case and control subjects. Data were collected for the main exposures of interest as well as pertinent covariates. Conditional logistic regression was used to evaluate therapeutic and environmental radiation as risks for IPT.Results
On univariate analysis, head or neck irradiation was associated with IPT (odds ratios [OR] = 4.15, 95% confidence interval [CI] = 1.30–13.24). While controlling for diabetes and family history of diabetes, IPT was found to be associated with both head or neck irradiation (OR = 4.06, 95% CI = 1.20–13.76) and with environmental irradiation (OR = 6.73, 95% CI = 1.06–42.74).Conclusions
This study presents a previously unreported association between prior radiation exposure and IPT. 相似文献87.
A J Roon W S Moore J Goldstone H Towan G Campagna 《The Journal of surgical research》1977,22(3):165-173
In order to study the comparative thrombogenicity of neointimal surfaces that develop with three types of vascular graft materials (ultralightweight knitted dacron, knitted dacron external velour, and expanded Teflon), 36 female mongrel dogs had their infrarenal aortas alternately replaced with one of the three grafts. At the end of 3 or 6 months, the grafts were removed and the surface thrombogenicity of the neointimal surface was determined. Each graft was examined visually and microscopically for evidence of “healing.” At 6 months the external velour graft is lined more frequently than the other two grafts. The external velour graft has a markedly better incidence of cellular healing noted microscopically than the other two grafts at both time intervals. While the expanded Teflon has an initially lower surface thrombogenicity (probably due to the characteristics of Teflon surface), at 6 months, the velour graft has the lowest surface thrombogenicity. This is most likely due to cellular healing. Of all the completely lined grafts at both time intervals, the surface thrombogenicity of the velour grafts was most like that of the normal aorta. The velour graft appears to develop the least thrombogenic neointimal surface while becoming most frequently healed with a cellular neointimal surface. 相似文献
88.
Complexity of the immunoglobulin light chain V kappa 1 gene family in the New Zealand black mouse 总被引:2,自引:0,他引:2
The immunoglobulin light chain V kappa 1 gene family is polymorphic in murine inbred strains and this family has been subdivided into five sub-groups (V kappa 1A-E). The V kappa 1A sub-group contributes to approximately 2% of the total serum immunoglobulin light chains in several mouse strains. However, it has been reported that this sub-group is absent in New Zealand Black (NZB) mouse serum. Amino acid sequencing of myeloma proteins from this inbred mouse has shown that they belong to the V kappa 1B sub-group. We report here the structure of nine functional germline genes from NZB mice that have high homologies to the V kappa 1A, V kappa 1B, V kappa 1C, and V kappa 1D sub-groups. In addition, a novel germline gene representing the prototype of a new sub-group (designated V kappa 1F) has been identified. We have isolated different V kappa 1 germline genes from a single restriction fragment length polymorphism (RFLP) fragment, as well as identical V genes from two different RFLP migrating bands. Therefore, the complexity of the genes encoding the immunoglobulin variable region cannot be determined solely by RFLP analysis. Nucleotide sequence analysis of 16 V kappa 1 genes which code for NZB autoantibodies indicate that they belong to five different V kappa 1 sub-groups with five hybridomas (31%) expressing the V kappa 1A sub-group. Comparison of the sequences of V kappa 1 genes expressed in hybridomas with corresponding germline genes show no somatic mutations. 相似文献
89.
A bloodless technique of evaluating protein catabolic rate (PCR) and KT/V (K, clearance; T, dialysis time; V, urea distribution volume) in hemodialysis patients is presented based on serial measurement of urea in the dialysate effluent stream. PCR follows from equating urea generation and urea removal over a 7 day cycle, changes in body stores being comparatively negligible: PCR = 0.026 [U1 + U2 + U3]/BWdry + 0.17, where U1 is the amount of urea in mmol appearing in the dialysate for each session in the 7 day period. KT/V is obtained from the slope of the natural logarithm of spent dialysate urea concentration-time plot: KT/V = [- slope.T + 3.delta BW/BWdry]/[1 - 0.01786.T(hr], where delta BW = amount ultrafiltered in liters. The dialysate-based approach was validated and compared with conventional urea kinetic modeling (UKM) for 17 patients studied for three consecutive dialyses. The dialysate-based and UKM values of PCR agreed well when in vivo clearance values based on total dialysate collection were used for UKM. KT/V values agreed poorly on a session-by-session basis but were nearly equivalent when averaged for the three dialyses of the week. These findings lay the foundation for UKM automation with a urea sensor in the effluent dialysate stream. 相似文献
90.
d,l-Camphor was detected as a new inducer of hydroxylase in the liver musomes of female mice. After a 2-day inhalation of d,l-camphor, cyt. P-450 and the ethylumbelliferone dealkylase were increased by 250 per cent and the NADPH-cyt. P-450 reductase by 350 per cent. The product [NADPH-cyt. P-450 reductase activity × cyt. P450 concentration] was shown to be a suitable reference parameter for the ethylumbelliferone dealkylase activity in the liver musomes during the treatment with four different inducers. The relative dealkylase activity Q was much decreased during inhalation of cyclohexane or d,l-camphor.Obviously these two inducers preferably enhanced cyt. P-450 species with a low dealkylase activity. The Q-values were reproducible. Q was increased by 100 per cent during induction of a MC-sensitive mouse strain with 3-methylcholanthrene, but it was only moderately decreased by induction with phenobarbital. Corresponding to this, methylcholanthrene is known to selectively induce a cyt. P-448 with high dealkylase activity whereas phenobarbital is known to change the hydroxylase specificity in the liver musomes not very much. 相似文献