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排序方式: 共有615条查询结果,搜索用时 51 毫秒
121.
CL 《Best Practice Onkologie》2012,7(1):39
Bei Tumorpatienten ist das Thromboserisiko deutlich erh?ht. Ursache dafür sind komplexe Wechselwirkungen zwischen Tumorzellen
in der Blutbahn und Endothelzellen, die die Thrombose- und wahrscheinlich auch die Metastasenbildung begünstigen. Der Einsatz
von Heparinen k?nnte sich daher in mehrfacher Hinsicht als sinnvoll erweisen. 相似文献
122.
Truwit J 《Clinics in Sports Medicine》2003,22(1):161-180
The respiratory system rarely limits exercise in the normal subject. In patients with chronic pulmonary processes or in the elite athlete, however, the respiratory system may indeed be the limiting factor. Common respiratory disorders include chest pain syndromes, cough, exercise-induced asthma, and vocal cord dysfunction. Chronic lung diseases such as asthma, COPD, and interstitial lung disease impact exercise capacity and endurance. Exercise testing can be useful to distinguish acute and chronic pulmonary causes of dyspnea during exercise, as well as to differentiate between cardiac and pulmonary causes. 相似文献
123.
124.
血、尿中安眠酮及其代谢物的测定 总被引:1,自引:0,他引:1
通过一例安眠酮中毒病人血、尿中安眠酮及其代谢物的测定,描述了用紫外光谱(uv)、气相色谱(GC)和气相色谱质谱(GC/MS)法测定安眠酮及其代谢物的系统分析方法。样品的提取净化采用液一液萃取和固相萃取两种方法,都得到了很好的结果。紫外光谱用于测定血、尿中安眠酮和其代谢物的总量;气相色谱用于测定血、尿中安眠酮原药的含量;气相色谱质谱则用于鉴定血、尿中的安眠酮及其代谢物。除安眠酮外,血、尿中共检出10种安眠酮代谢物,其中包括两种乙酰化代谢物。此法还为临床救治提供指导。 相似文献
125.
I L Kron C G Tribble J A Kern T M Daniel C E Rose J D Truwit L H Blackbourne J D Bergin 《Annals of surgery》1993,217(5):518-524
OBJECTIVE: This study evaluates the efficacy of personally inspecting marginal thoracic organ donors to expand the donor pool. SUMMARY BACKGROUND DATA: The present donor criteria for heart and lung transplantation are very strict and result in exclusion of many potential thoracic organ donors. Due to a limited donor pool, 20-30% of patients die waiting for transplantation. METHODS: The authors have performed a prospective study of personally inspecting marginal donor organs that previously would have been rejected by standard donor criteria. RESULTS: Fourteen marginal hearts and eleven marginal lungs were inspected. All 14 marginal hearts and 10 of the marginal lungs were transplanted. All cardiac transplant patients did well. The mean ejection fraction of the donor hearts preoperatively was 39 +/- 11% (range 15-50%). Postoperatively, the ejection fraction of the donor hearts improved significantly to 55 +/- 3% (p < 0.002). Nine of the ten lung transplant patients did well and were operative survivors. Our donor pool expanded by 36% over the study period. CONCLUSIONS: The present donor criteria for heart and lung transplantation are too strict. Personal inspection of marginal thoracic donor organs will help to maximize donor utilization. 相似文献
126.
The tendency for sickle cells to adhere to each other is increased in oxygenated sickle blood in parallel with cell density. The increased adherence of these cells occurred despite their reduced deformability and diminished ability to form rouleaux. Using a method developed in our laboratory, we measured the yield stress: a sensitive index of cell- cell adhesion of deoxygenated suspensions of sickle cells. Deoxygenation of whole sickle blood to 30 to 50 mm Hg caused a significant increase in yield stress of all sickle blood samples. Deoxygenation caused a significant increase in yield stress of both dense and light sickle cells. Deoxygenation-induced increases in yield stress occurred at higher oxygen tensions for dense (> 55 mm Hg) than for light sickle cells (< 45 mm Hg). The increase in yield stress on deoxygenation was correlated with hemoglobin polymerization as assessed morphologically by sickling or by changes in relative viscosity. Thus, deoxygenation-induced cell sticking must involve small areas of strong membrane adhesion because the changes in yield stress occurred despite a reduction in rouleaux formation and surface area of membrane contact. Sickle trait red blood cells also exhibited increased yield stress on deoxygenation but only under hypertonic conditions where sickling occurred. Thus, deoxygenation-induced cell adhesion did not require prior membrane damage because it occurred in sickle trait cells. No change in yield stress was seen when deoxygenated sickle cells were suspended in buffer, but the addition of physiologic amounts of fibrinogen to buffer restored the deoxygenation-induced increase in cell adhesion. We speculate that the increase in sticking among sickle cells on deoxygenation results from spicule formation and may involve interaction of fibrinogen and possibly other plasma proteins with the cell membrane. 相似文献
127.
石南藤、山蒟活性成分的分离和结构鉴定 总被引:4,自引:0,他引:4
已报道自山蒟及石南藤中分得海风藤酮(Ⅰ),denudatin B(Ⅱ),N-isobutyl-deca-trans-2-trans-4-dienamide(Ⅲ),本文继续报道自山蒟中分得一新木脂素,命名为山蒟素D(Ⅳ),X-衍射晶体结构测定为外消旋光学异构体。自石南藤分得Ⅳ的同系物,为新结构、命名为南藤素(Ⅴ),以及山蒟素C(Ⅵ),galgravin(Ⅶ),二氢毕拨明宁碱(Ⅷ)及巴豆环氧素(Ⅸ)。以上化合物皆首次自山蒟及石南藤中分得。以血小板活化因子(PAF)引起的血小板凝集实验测定活性,除Ⅲ,Ⅳ,Ⅶ,Ⅸ外皆有抑制活性。 相似文献
128.
Increased detection of hepatitis C virus infection in commercial plasma donors by a third-generation screening assay 总被引:4,自引:0,他引:4
SR Lee ; CL Wood ; MJ Lane ; B Francis ; C Gust ; CM Higgs ; MJ Nelles ; A Polito ; R DiNello ; D Achord 《Transfusion》1995,35(10):845-849
BACKGROUND: Routine screening of blood donations with second-generation hepatitis hepatitis C virus (HCV) assays has substantially reduced the occurrence of posttransfusion hepatitis. However, following the development of third-generation assays, several studies indicated that these assays may identify HCV-infected individuals who are not identified by second-generation assays. STUDY DESIGN AND METHODS: The sensitivity of a third-generation HCV enzyme-linked immunosorbent assay (ELISA-3) was compared with a second-generation ELISA (ELISA-2) in a side-by-side study of 9936 commercial blood donors. ELISA-reactive specimens were subjected to supplemental analysis by third-generation recombinant immunoblot assay and polymerase chain reaction. RESULTS: ELISA-3 demonstrated greater sensitivity than ELISA-2, detecting 1 additional recombinant immunoblot assay-positive specimen per 2000 tested. ELISA-3 also detected 1 additional HCV-infectious polymerase chain reaction-positive unit among approximately 10,000 units screened. CONCLUSION: The incremental sensitivity achieved with ELISA-3 can be expected to eliminate approximately 20 infectious donations per week among those made by commercial donors in the United States. In accordance with previous studies, most of the improved sensitivity of ELISA-3 derives from its increased detection of anti-c33c (NS3), rather than from the inclusion of HCV antigen NS5. 相似文献
129.
Cerebral palsy: MR findings in 40 patients. 总被引:20,自引:0,他引:20
C L Truwit A J Barkovich T K Koch D M Ferriero 《AJNR. American journal of neuroradiology》1992,13(1):67-78
PURPOSE: We used MR to retrospectively analyze the brains of patients suffering from cerebral palsy, our aim being to determine MR's role in the assessment of brain damage and the relationship of pre-, peri-, and post-natal events to cerebral palsy. METHODS: Forty patients (aged 1 month to 41 years) underwent MR scanning and findings were correlated with clinical histories in all cases. RESULTS: Review of MR scans of 11 patients who had been born prematurely revealed findings of periventricular white matter damage, indicative of hypoxic-ischemic brain injury (82%), the chronology of which was difficult to determine. Among 29 patients who had been born at term, three major patterns emerged: (1), gyral anomalies, suggestive of polymicrogyria, consistent with mid-second trimester injury; (2), isolated periventricular leukomalacia reflecting late second- or early third-trimester injury; and (3), watershed cortical or deep gray nuclear damage, consistent with late third-trimester, perinatal or postnatal injury. In 16 (55%) of 29 patients born at term, MR findings of intrauterine brain damage were observed; in over half of these cases MR revealed developmental anomalies, which is nearly twice the rate reported in prior studies employing CT. CONCLUSIONS: Our results support a growing consensus that cerebral palsy in term infants is often the result of prenatal factors, and less commonly related to the perinatal period. 相似文献
130.
Clinical application of human egg cryopreservation 总被引:20,自引:17,他引:3
Tucker MJ; Morton PC; Wright G; Sweitzer CL; Massey JB 《Human reproduction (Oxford, England)》1998,13(11):3156-3159
Clinical egg cryopreservation has been applied during a 4-year period with
some limited success. Mostly mature and a few immature eggs were frozen
slowly and thawed rapidly in 1,2-propanediol and sucrose, and subsequently
inseminated by intracytoplasmic sperm injection (ICSI). Three studies were
performed in which: (i) it was established that 55% of aged unfertilized
mature eggs survive freezing; (ii) in 22 cycles of thawed donated eggs
cryosurvival was 24% with 15 cycles reaching transfer, and five pregnancies
were initiated, one of which went to term at 39 weeks with fraternal twin
boys, and one remains ongoing at 37 weeks; and (iii) in five cycles, where
in-vitro fertilization patients had some of their own eggs frozen/ thawed,
cryosurvival of mature eggs was poor at only 2.2%, although 44% sibling
germinal vesicle (GV) stage eggs survived. A normal female infant delivered
at 40 weeks arose from transfer of two embryos where GV eggs underwent in-
vitro maturation post-thaw and were fertilized by ICSI. Pregnancies
reported here and by others indicate a burgeoning awareness of the
potential benefits of egg cryopreservation, prompting cautious optimism for
the future of this technology.
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