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1.
Liver hemangioma: US-guided 18-gauge core-needle biopsy   总被引:6,自引:0,他引:6  
Heilo  A; Stenwig  AE 《Radiology》1997,204(3):719
  相似文献   
2.
Bone scintigraphy of the hands and wrists represents an important adjunct imaging technique that complements plain film radiographic examination in the evaluation of chronic wrist pain. In this study, the effectiveness of bone scintigraphy was investigated in the evaluation of chronic wrist pain in the patients without the history of trauma and any radiological and rheumatological abnormalities. Seventy-one patients with normal conventional radiographs and unexplained wrist pain were evaluated prospectively between 1998 and 2003 in our hand surgery clinic. There was no trauma history and no specific physical examination findings in the patients. The bone scintigraphy was done in all patients. Fifty-two of the all patients had normal scintigram. Seventeen of the remaining 19 patients showed increased activity over triquetrum (5 cases), lunatum (4 cases), trapezium (4 cases), hamatum (2 cases) and psiforme (2 cases). As the additional radiological investigations like MRI and CT revealed no bony abnormalities, the results of bone scintigraphy were evaluated as chronic ligamentous injuries. Two patients had diffuse increased uptake compatible with synovitis. The evaluation of bone scintigraphy correlated with clinical findings is effective to choose the most efficient treatment method in chronic wrist pain.  相似文献   
3.
Tranilast is an antiallergic drug that interferes with proliferation and migration of vascular smooth muscle cell induced by platelet-derived growth factor (PDGF) and transforming growth factor-beta1 (TGF-beta1). We investigated the local effect of tranilast on neointimal hyperplasia using tranilast-coated prosthetic grafts. The inner sides of the thin-walled polytetrafluoroethylene (PTFE) grafts were coated with chitosan and tranilast containing chitosan solution. Wistar albino rats (32) were used in the study. Patches (1 x 2 mm) for vascular grafts were prepared. Three groups were tested: group 1 (n = 12; tranilast coated), group 2 (n = 10; adhesive-only film-layer-coated), and group 3 (n = 10; normal ePTFE patch grafts sutured to the carotid arteries of the rats). Recipient sites of the carotid arteries were excised 4 weeks after surgery. All sections were examined histologically for graft patency, thrombus formation, and neointimal thickness. Expression of PDGF, fibroblast growth factor, and TGF-beta1 on cross-sections of the neointima were evaluated by immunohistochemistry. No significant differences were found regarding mean neointimal thicknesses. PDGF and TGF-beta-1 expressions were significantly lower in group 1. Although a decrease in local effect of tranilast was observed for growth factor expressions at a drug concentration of 0.05 mg/cm(2), a significant reduction in neointimal hyperplasia was not achieved. The coating concentration of 0.05 mg/cm(2) may have been too low to produce an antiproliferative effect. Given our promising results, further studies are recommended and planned using different drug concentrations and time intervals.  相似文献   
4.
BACKGROUND: There are obvious advantages to increasing donor retention. However, for reasons of blood safety, certain donors may, in fact, be more desirable to retain than others. “Safe” donors are defined as those who provided a blood donation that was negative on all laboratory screening tests and who subsequently reported no behavioral risks in response to an anonymous survey. This study identifies the most important factors affecting the intention of “safe” donors to provide another donation. STUDY DESIGN AND METHODS: An anonymous survey asking about donation history, sexual history, injecting drug use, and recent donation experience was mailed to 50,162 randomly selected allogeneic donors (including directed donors) who gave blood from April through July or from October through December 1993 at one of the five United States blood centers participating in the Retrovirus Epidemiology Donor Study. Before mailing, questionnaires were coded to designate donors with nonreactive laboratory screening tests at their most recent donation. RESULTS: A total of 34,726 donors (69%) responded, with substantially higher response among repeat donors. According to reported intentions only, the vast majority of “safe” donors indicated a high likelihood of donating again within the next 12 months. Only 3.4 percent reported a low likelihood of donating again. A comparison of those likely to return and those unlikely to return reveals significant differences in demographics and in ratings of the donation experience. A higher proportion of those unlikely to return were first-time donors, minority-group donors, and donors with less education. The highest projected loss among “safe” donors was seen for those who gave a fair to poor assessment of their treatment by blood center staff or of their physical well-being during or after donating. CONCLUSION: These data suggest that efforts to improve donors' perceptions of their donation experience, as well as attention to the physical effects of blood donation, may aid in the retention of both repeat and first-time donors.  相似文献   
5.
Products of the Frizzled family of tissue polarity genes have been identified as putative receptors for the Wnt family of signaling molecules. Wnt-signaling is implicated in the regulation of limb mesenchymal chondrogenesis, and our recent study indicates that N-cadherin and related activities are functionally involved in Wnt-7a-mediated inhibition of chondrogenesis. By using an in vitro high-density micromass culture system of chick limb mesenchymal cells, we have analyzed the spatiotemporal expression patterns and the effects on chondrogenesis of RCAS retroviral-mediated misexpression of Chfz-1 and Chfz-7, two Frizzled genes implicated in chondrogenic regulation. Chfz-1 expression was localized at areas surrounding the cartilaginous nodules at all time points examined, whereas Chfz-7 expression was limited to cellular aggregates during initial mesenchymal condensation, and subsequently was down-regulated from the centers toward the periphery of cartilage nodules at the time of chondrogenic differentiation, resembling the pattern of N-cadherin expression. Chondrogenesis in vitro was inhibited and limited to a smaller area of the culture upon misexpression of Chfz-7, but not affected by Chfz-1 misexpression. Analyses of cellular condensation and chondrogenic differentiation showed that the inhibitory action of Chfz-7 is unlikely to be at the chondrogenic differentiation step, but instead affects the earlier precartilage aggregate formation event. At 24 hr, expression of N-cadherin, a key component of the cellular condensation phase of chondrogenesis, was delayed/suppressed in Chfz-7 misexpressing cultures, and was limited to a significantly smaller cellular condensation area within the entire culture at 48 hr, when compared with control cultures. Chfz-1 misexpressing cultures appeared similar to control cultures at all time points. However, neither Chfz-1 nor Chfz-7 misexpression affected mesenchymal cell proliferation in vitro. These results suggest that Chfz-7 is active in regulating N-cadherin expression during the process of limb mesenchymal chondrogenesis and that Chfz-1 and Chfz-7 are involved in different Wnt-signaling pathways.  相似文献   
6.
Crosslineage T-cell receptor delta (TCR delta) rearrangements are widely used as tumor markers for the follow up of minimal residual disease in childhood B-precursor acute lymphoblastic leukemia (ALL) by polymerase chain reaction (PCR). The major drawback of this approach is the risk of false-negative results due to clonal evolution. We investigated the stability of V delta 2D delta 3 rearrangements in a group of 56 childhood B-precursor ALL patients by PCR and Southern blot analysis. At the PCR level, V delta 2D delta 3-to-J alpha rearranged subclones (one pathway for secondary TCR delta recombination) were demonstrated in 85.2% of V delta 2D delta 3-positive patients tested, which showed that small subclones are present in the large majority of patients despite apparently monoclonal TCR delta Southern blot patterns. Sequence analysis of V delta 2D delta 3J alpha rearrangements showed a biased J alpha gene usage, with HAPO5 and J alpha F in 26 of 32 and 6 of 32 clones, respectively. Comparison of V delta 2D delta 3 rearrangement status between diagnosis and first relapse showed differences in seven of eight patients studied. In contrast, from first relapse onward, no clonal changes were observed in six patients studied. To investigate the occurrence of crosslineage TCR delta rearrangements in normal B and T cells, fluorescence-activated cell sorter-sorted peripheral blood CD19+/CD3- and CD19-/CD3+ cell populations from three healthy donors were analyzed. V delta 2D delta 3 rearrangements were detected at low frequencies in both B and T cells, which suggests that V delta 2-to-D delta 3 joining also occurs during normal B-cell differentiation. A model for crosslineage TCR delta rearrangements in B-precursor ALL is deduced that explains the observed clonal changes between diagnosis and relapse and is compatible with multistep leukemogenesis of B-precursor ALL.  相似文献   
7.
Intracerebral vascular reactivity induced by the nitric oxide (NO) donor isosorbide dinitrate (IDN, 5 mg sublingually) is more major and longer-lasting in migraine patients who develop delayed headache in response to the drug. The headache is purportedly due to neuronally-mediated vascular mechanisms. Indomethacin inhibits prostaglandin synthesis, which is involved in NO generation. Indomethacin also decreases cerebral blood flow by constricting precapillary resistance vessels. In the present study, the hemodynamic effects of indomethacin were evaluated in migraine patients and healthy controls by means of transcranial Doppler monitoring. Indomethacin caused a significant decrease in mean flow velocity in the middle cerebral artery. This was an additional effect to the mean velocity decrease induced by IDN. The interactions between the two drugs suggest that their effects on cerebral hemodynamics (and pain) may be of relevance both in understanding the role of NO in migraine pathogenesis and in evaluating symptomatic treatments for migraine attacks.  相似文献   
8.
9.
Objective: Right upper lobe collapse is a common radiographic finding in intubated children. We hypothesized that deep suctioning and uncontrolled negative pressures during endotracheal tube suctioning were significant contributory factors. Methods : The incidence of right upper lobe (RUL) collapse in intubated, ventilated children on a paediatric cardiac intensive care unit was determined over a 3-month period ( n = 102). Graduated suction catheters and suction vacuums of < 165 cm H2O were then introduced. Another prospective audit was carried out 3 months later ( n = 60). Results : We found that 24% developed RUL collapse and 4 developed an apical pneumothorax. Following the introduction of graduated catheters and controlled vacuums pressures, a significant reduction in the incidence of RUL collapse, to 7%, was observed ( p < 0.05). Conclusions : We conclude that high negative pressure and deep-suctioning causes RUL collapse in children. Any lobar collapse not only prolongs the child's stay in intensive care, but can be associated with further morbidity which may have a serious implication. By improving suctioning technique this morbidity can be significantly reduced.  相似文献   
10.
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