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991.
We compared intraarterial digital subtraction angiography (DSA) studies with those of conventional angiography, performed for 24 patients who had intracranial tumors. Intraarterial DSA is more effective in evaluating tumoral blush and venous phase, but neovascularization can be judged better by conventional angiography. In most cases, intraarterial DSA can replace conventional angiography for the diagnostic and preoperative evaluation of intracranial tumors. However, conventional angiography remains the technique of choice for the evaluation of neovascularization or if the patient is not cooperative. 相似文献
992.
Twenty-two patients with clinical findings consistent with osteomyelitis, soft-tissue infection, or both were studied with magnetic resonance (MR) imaging at 1.5 T. Another 15 patients with joint effusion but no clinical or laboratory signs of infection served as controls. Soft-tissue abscesses, osteomyelitis, joint and tendon sheath effusion, and cellulitis were well depicted on MR imaging, allowing the correct diagnosis of presence and extent of infection in all but two cases. MR imaging was as sensitive as technetium-99m methylene diphosphonate bone scintigraphy in demonstrating osteomyelitis and was more specific and more sensitive than other scintigraphic techniques in demonstrating soft-tissue infections, primarily because of its superior spatial resolution. Computed tomography, performed in seven cases, was as accurate as MR imaging in demonstrating bone and soft-tissue infections. Infected and noninfected synovial effusions had the same signal intensity, but associated findings such as soft-tissue fluid collections or osteomyelitis made the distinction possible. 相似文献
993.
Stehling MK; Evans DF; Lamont G; Ordidge RJ; Howseman AM; Chapman B; Coxon R; Mansfield P; Hardcastle JD; Coupland RE 《Radiology》1989,171(1):41-46
Gastrointestinal (GI) tract motility was depicted in four human volunteers with the high-speed echo-planar imaging technique: modulus blipped echo-planar single-pulse technique (MBEST). Data acquisition times of 64 and 128 msec obviate image degradation due to motion without the need for gut paralysis and allow imaging of the GI tract in real time. Peristaltic patterns of the gastric antrum and proximal small intestine were depicted for fasting and fed subjects and subjects in whom peristalsis had been pharmacologically stimulated. The potential for quantitative measurements of GI tract motion with this new technique was demonstrated. 相似文献
994.
Irish Journal of Medical Science (1971 -) - 相似文献
995.
AM?PatwardhanEmail author VS?Lad N?Kumar S?Agarwala C?Binoy NB?Agrawal VB?Pai JV?Khandekar BV?Dalvi YY?Lokhandwala 《Indian Journal of Thoracic and Cardiovascular Surgery》2003,19(3):136-140
Background We studied the effectiveness of Radiofrequency (RF) modified maze in early and late restoration of sinus rhythm in patients
with rheumatic heart disease (RHD).
Methods We studied 84 patients with RHD over 23.6±12.5 months after the RF modified maze and another group of 64 patients over six
months after valvular surgery alone (the Non-Maze group). Any thromboembolic episodes and NYHA class of the patient were recorded.
The short term survivors in sinus rhythm, underwent stress test and echocardiography for atrial transport function at 3–6
months after surgery.
Results In the Maze group, sinus rhythm was restored in 60/70 patients (85.71%) immediately and sustained in 55/70 patients (78.57%)
over the follow-up as against an immediate conversion rate of 5.3% (5/53 patients, p<0.001) in the Non-maze group. The additional
Cardiopulmonary (CP) bypass time (p=0.13) and cross clamp time (p=0.511) needed for maze is not statistically significant.
Left atrial (LA) transport function was preserved in 41/51 patients (80.4%) and Right atrial (RA) transport function in 51/51
patients (100%). Stress test showed good chronotropic response in all the 41 patients in whom it was performed. In the Maze
group one patient presented with acute valve thrombosis and subsequently, succumbed to it. In the non maze group 3/55 patients
(5.66%) were hospitalized for stroke. No patient needed permanent pacemaker nor was sinus node dysfunction seen. The immediate
postoperative morbidity and mortality was comparable in the two groups.
Conclusions The RF modified maze is safe, effective and brief without any additional risk. It restores sinus rhythm in the majority, however
there is an attrition in some. 相似文献
996.
Bollen J Polstra A Van Der Kuyl A Weel J Noorduyn L Van Oers M Cornelissen M 《BMC blood disorders》2003,3(1):3
Background
Multicentric Castleman's disease (MCD) is a rare disease, but is more frequent in AIDS patients. MCD has only been reported twice before in patients receiving immunosuppressive therapy after renal transplantation, and never in patients receiving immunosuppressive therapy without transplantation. About half of the cases of MCD are human herpesvirus 8 (HHV8) – related, in contrast to Kaposi's sarcoma, a more common complication arising after immunosuppression, where the virus is found in virtually all cases. 相似文献997.
AM Havens Y Jung YX Sun J Wang RB Shah HJ Bühring KJ Pienta RS Taichman 《BMC cancer》2006,6(1):195-13
Background
The chemokine stromal derived factor-1 (SDF-1 or CXCL12) and its receptor CXCR4 have been demonstrated to be crucial for the homing of stem cells and prostate cancers to the marrow. While screening prostate cancers for CXCL12-responsive adhesion molecules, we identified CD164 (MGC-24) as a potential regulator of homing. CD164 is known to function as a receptor that regulates stem cell localization to the bone marrow. 相似文献998.
hMLH1 and hMSH2 expression and BAX frameshift mutations in ovarian cancer cell lines and tumors 总被引:2,自引:0,他引:2
Colella G; Vikhanskaya F; Codegoni AM; Bonazzi C; D'Incalci M; Broggini M 《Carcinogenesis》1998,19(4):691-694
The expression of mismatch repair proteins hMSH2 and hMLH1 was investigated
in human ovarian cancer cell lines and in biopsies of ovarian carcinomas
obtained from 20 patients undergoing surgical operation. By Western
blotting analysis hMSH2 protein was detected in all the tumor samples
analyzed and in eight out of nine human ovarian cancer cell lines, while
hMLH1 was undetectable in four out of 20 ovarian tumors and in five out of
nine human ovarian cancer cell lines analyzed. The possible presence of
frameshift mutations in the BAX gene, which contains a sequence of eight
contiguous guanines in its third exon, was tested in all the samples. All
the cell lines presented the normal alleles for the BAX gene while only in
one of the tumor samples a heterozygous frameshift mutation was found. The
frameshift mutation was associated to a low, almost undetectable, level of
BAX protein which was instead present at much higher levels in all the
other samples investigated. The results indicate that frameshift mutations
in the BAX gene, possibly arising as a consequence of microsatellite
instability (detectable in these tumors), is detectable in human ovarian
cancer although quantitatively it does not appear to be a major determinant
of the low apoptotic response to chemotherapy observed in ovarian cancer
cells.
相似文献
999.
The effects of H2O2-induced oxidative DNA damage in 80 healthy individuals
with relation to age (20-25 and 55-60 years old) and smoking has been
investigated with the comet assay technique. Both factors have shown a
significant effect upon basal DNA damage with smoking appearing to have the
most impact. A differentiation of the four groups response to induced
oxidative damage was also observed. A distinctly separate behavior of the
younger non-smokers group, when compared with the rest of the categories,
was found. This is attributed to the lower degree of initial basal damage
that occurs in their lymphocytes.
相似文献
1000.
To study the effects of carotenoids on the initiation of liver
carcinogenesis by aflatoxin B1 (AFB1), male weanling rats were fed beta-
carotene, beta-apo-8'-carotenal, canthaxanthin, astaxanthin or lycopene
(300 mg/kg diet), or an excess of vitamin A (21000 RE/kg diet), or were
injected i.p. with 3-methylcholanthrene (3-MC) (6 x 20 mg/kg body wt)
before and during i.p. treatment with AFB1 (2 x 1 mg/kg body wt). The rats
were later submitted to 2-acetylaminofluorene treatment and partial
hepatectomy, and placental glutathione S-transferase-positive liver foci
were detected and quantified. The in vivo effects of carotenoids or of 3-MC
on AFB1-induced liver DNA damage were evaluated using different endpoints:
liver DNA single-strand breaks (SSB) induced by AFB1, and in vivo binding
of [3H]AFB1 to liver DNA and plasma albumin. Finally, the modulation of
AFB1 metabolism by carotenoids or by 3-MC was investigated in vitro by
incubating [14C]AFB1 with liver microsomes from rats that had been fed with
carotenoids or treated by 3- MC, and the metabolites formed by HPLC were
analyzed. In contrast to lycopene or to an excess of vitamin A, both of
which had no effect, beta-carotene, beta-apo-8'carotenal, astaxanthin and
canthaxanthin, as well as 3-MC, were very efficient in reducing the number
and the size of liver preneoplastic foci. In a similar way as 3-MC, the
P4501A- inducer carotenoids, beta-apo-8'-carotenal astaxanthin and
canthaxanthin, decreased in vivo AFB1-induced DNA SSB and the binding of
AFB1 to liver DNA and plasma albumin, and increased in vitro AFB1
metabolism to aflatoxin M1, a less genotoxic metabolite. It is concluded
that these carotenoids exert their protective effect through the deviation
of AFB1 metabolism towards detoxication pathways. In contrast,
beta-carotene did not protect hepatic DNA from AFB1-induced alterations,
and caused only minor changes of AFB1 metabolism: seemingly, its protective
effect against the initiation of liver preneoplastic foci by AFB1 is
mediated by other mechanisms.
相似文献