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排序方式: 共有1063条查询结果,搜索用时 31 毫秒
1.
Liver hemangioma: US-guided 18-gauge core-needle biopsy 总被引:6,自引:0,他引:6
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V V Aleksi-Meskhishvili A P Nikoliuk V A Garibian V I Borisov L A Vedernikova V N Il'in 《Grudnaia i serdechno-sosudistaia khirurgiia / Ministerstvo zdravookhraneniia SSSR [i] Vsesoiuznoe nauchnoe obshchestvo khirurgov》1990,(2):19-25
The article generalizes the experience in surgical treatment of Fallot's tetrad in 20 infants. Radical correction of the anomaly was carried out under extracorporeal circulation and deep hypothermia with reduced volume rate of perfusion. Plastics of the conus arteriosus alone was performed in 6 patients, transanulus and the pulmonary trunk in 4 patients. Two patients died, the hospital lethality was 10%. A clinical effect was produced in all the other patients. The relation of systolic pressure in the left ventricle to that in the right ventricle was 0.56 +/- 0.1, the systolic pressure gradient between the right ventricle and the pulmonary artery was 18 +/- 4.2 mm Hg. Various degree of regurgitation at the pulmonary valve was revealed after the operation in all patients. It was maximum (34 +/- 10%) in transanulus plastics. 相似文献
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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
6.
Steenbergen EJ; Verhagen OJ; van Leeuwen EF; van den Berg H; von dem Borne AE; van der Schoot CE 《Blood》1995,86(2):692-702
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.
AE Castellano G Micieli P Bellantonio MG Buzzi S Marcheselli F Pompeo F Rossi G Nappi 《Cephalalgia : an international journal of headache》1998,18(9):622-630
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
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R. Kh. Mudarisova E. N. Shirokova L. A. Badykova I. M. Borisov T. G. Tolstikova I. V. Sorokina M. P. Dolgikh Yu. B. Monakov 《Pharmaceutical Chemistry Journal》2005,39(8):418-421
Aqueous solutions of arabinogalactan from Siberian larch (Larix sibirica L.) were subjected to oxidative destruction by a hydrogen peroxide – molecular oxygen system. The obtained high- and low-molecular-weight
fractions of oxidation products were characterized by chemical and spectral methods and tested for pharmacological activity.
The results of experiments on animals showed evidence for significant antiulcer and antiinflammatory properties of the preparations
studied.
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Translated from Khimiko-Farmatsevticheskii Zhurnal, Vol. 39, No. 8, pp. 23 – 26, August, 2005. 相似文献
10.
V P Borisov B A Popov L I Seletskaia F A Belinskaia V A Kaliuzhny? 《Gigiena i sanitariia》1989,(4):19-21
In consequence of the test of Ferriferrocyanide efficiency under the intoxication of white rats by 137Cs the dependence of its sorption effect on the chemical form, production process and the degree of dispersion of the preparation is demonstrated. Maximum efficiency has been determined in Ferriferrocyanides when their degree of dispersion is 0.02-0.03 mm. Antidote qualities of the preparations can be preserved for 15 years. 相似文献