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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.
Infections of the musculoskeletal system: high-field-strength MR imaging   总被引:1,自引:0,他引:1  
Beltran  J; Noto  AM; McGhee  RB; Freedy  RM; McCalla  MS 《Radiology》1987,164(2):449-454
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.
Gastrointestinal tract: dynamic MR studies with echo-planar imaging   总被引:2,自引:0,他引:2  
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.
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.

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.
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   
998.
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   
999.
Mothers'perceptions of desirable nutritional practices in infant feeding were examined using a questionnaire consisting of open and closed questions. A total of 1004 mother–infant pairs were recruited from a mixture of urban and rural areas in England. The sample represented a cross–section of socioeconomic groups and educational backgrounds. Mothers'attitudes to healthy eating for infants revealed some misconceptions; 83% felt that a high fibre intake was important or very important and 87% that a low fat intake was important or very important, while 20% considered that plenty of calories was not important. Other health guidelines were appropriately applied and most mothers considered a wide variety of foods, plenty to drink and a low sugar and salt intake to be important. These beliefs were representative of the sample population, irrespective of the socioeconomic group, location, age and education of the mother.  相似文献   
1000.
The successful correction of infantile osteopetrosis in an Asian child by bone marrow transplantation (BMT) from an HLA-A,B matched cousin donor is reported. Retrospective HLA molecular analysis revealed that patient and donor were incompatible for HLA-DPB1. Donor type cells detected in the patient after transplantation indicate successful engraftment. The patient is currently alive and well.  相似文献   
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