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排序方式: 共有2237条查询结果,搜索用时 15 毫秒
81.
82.
Activated protein C decreases plasminogen activator-inhibitor activity in endothelial cell-conditioned medium 总被引:12,自引:0,他引:12
van Hinsbergh VW; Bertina RM; van Wijngaarden A; van Tilburg NH; Emeis JJ; Haverkate F 《Blood》1985,65(2):444-451
Confluent cultures of endothelial cells from human umbilical cord were used to study the effect of activated human protein C (APC) on the production of plasminogen activators, plasminogen activator-inhibitor, and factor VIII-related antigen. Addition of APC to the cells in a serum-free medium did not affect the production of tissue-type plasminogen activator (t-PA) or factor VIII-related antigen; under all measured conditions, no urokinase activity was found. However, less plasminogen activator-inhibitor activity accumulated in the conditioned medium in the presence of APC. This decrease was dose dependent and could be prevented by specific anti-protein C antibodies. No decrease was observed with the zymogen protein C or with diisopropylfluorophosphate-inactivated APC. APC also decreased the t-PA inhibitor activity in endothelial cell-conditioned medium in the absence of cells, which suggests that the effect of APC is at least partly due to a direct effect of APC on the plasminogen activator- inhibitor. High concentrations of thrombin-but not of factor Xa or IXa-- had a similar effect on the t-PA inhibitor activity. The effect of APC on the plasminogen activator-inhibitor provides a new mechanism by which APC may enhance fibrinolysis. The data suggest that activation of the coagulation system may lead to a secondary increase of the fibrinolytic activity by changing the balance between plasminogen activator(s) and its (their) fast-acting inhibitor. 相似文献
83.
84.
AG Eller TF Porter P Soisson RM Silver 《BJOG : an international journal of obstetrics and gynaecology》2009,116(5):648-654
Objective To determine which interventions for managing placenta accreta were associated with reduced maternal morbidity.
Design Retrospective cohort study.
Setting Two tertiary care teaching hospitals in Utah.
Population All identified cases of placenta accreta from 1996 to 2008.
Methods Cases of placenta accreta were identified using standard ICD-9 codes for placenta accreta, placenta praevia, and caesarean hysterectomy. Medical records were then abstracted for maternal medical history, hospital course, and maternal and neonatal outcomes. Maternal and neonatal complications were compared according to antenatal suspicion of accreta, indications for delivery, preoperative preparation, attempts at placental removal before hysterectomy, and hypogastric artery ligation.
Main outcome measures Early morbidity (prolonged maternal intensive care unit admission, large volume of blood transfusion, coagulopathy, ureteral injury, or early re-operation) and late morbidity (intra-abdominal infection, hospital re-admission, or need for delayed re-operation).
Results Seventy-six cases of placenta accreta were identified. When accreta was suspected, scheduled caesarean hysterectomy without attempting placental removal was associated with a significantly reduced rate of early morbidity compared with cases in which placental removal was attempted (67 versus 36%, P = 0.038). Women with preoperative bilateral ureteric stents had a lower incidence of early morbidity compared with women without stents (18 versus 55%, P = 0.018). Hypogastric artery ligation did not reduce maternal morbidity.
Conclusions Scheduled caesarean hysterectomy with preoperative ureteric stent placement and avoiding attempted placental removal are associated with reduced maternal morbidity in women with suspected placenta accreta. 相似文献
Design Retrospective cohort study.
Setting Two tertiary care teaching hospitals in Utah.
Population All identified cases of placenta accreta from 1996 to 2008.
Methods Cases of placenta accreta were identified using standard ICD-9 codes for placenta accreta, placenta praevia, and caesarean hysterectomy. Medical records were then abstracted for maternal medical history, hospital course, and maternal and neonatal outcomes. Maternal and neonatal complications were compared according to antenatal suspicion of accreta, indications for delivery, preoperative preparation, attempts at placental removal before hysterectomy, and hypogastric artery ligation.
Main outcome measures Early morbidity (prolonged maternal intensive care unit admission, large volume of blood transfusion, coagulopathy, ureteral injury, or early re-operation) and late morbidity (intra-abdominal infection, hospital re-admission, or need for delayed re-operation).
Results Seventy-six cases of placenta accreta were identified. When accreta was suspected, scheduled caesarean hysterectomy without attempting placental removal was associated with a significantly reduced rate of early morbidity compared with cases in which placental removal was attempted (67 versus 36%, P = 0.038). Women with preoperative bilateral ureteric stents had a lower incidence of early morbidity compared with women without stents (18 versus 55%, P = 0.018). Hypogastric artery ligation did not reduce maternal morbidity.
Conclusions Scheduled caesarean hysterectomy with preoperative ureteric stent placement and avoiding attempted placental removal are associated with reduced maternal morbidity in women with suspected placenta accreta. 相似文献
85.
86.
Sarah Lake MN RN Cheryle Moss PhD RN Jan Duke PhD RN RM 《International journal of nursing practice》2009,15(5):376-388
Every day in clinical settings, nurses practise in complex and dynamic situations. Nurses work to achieve emergent order in these situations through nursing prioritization of the patient need for care. As direct research on nursing prioritization had not been reported, a study, using critical realism as method, was designed to discern the profession's embedded understanding from within the clinical decision-making literature. The research synthesizes a tacit knowledge on nursing prioritization of the patient need for care from key international literature (from 1966 to 2003). Nursing prioritization was discerned in both education and practice literatures; interrelationships between these and theoretical approaches were also identified. Nursing prioritization of the patient need for care was revealed both as a non-sequential decision-making process throughout unfolding patient situations and as an advanced skill of nursing practice. Increasing confidence with this skill is the hallmark of developing expertise. 相似文献
87.
88.
Chronic active plasmacytic gastritis (CAPG) is characterized by the presence of chronic inflammatory cell infiltrates, mainly formed by plasma cells, involving the neck of gastric glands. This lesion, as well as Ménétrier disease, has been linked to cytomegalovirus (CMV). To test this association we evaluated the foveolar/glandular (F/G) index and the presence of CMV DNA (desoxirribonucleic acid) by means of polymerase chain reaction (PCR) in 12 cases of CAPG and 13 controls. Cases exhibiting CAPG included 2 with Ménétrier disease, 6 with foveolar hyperplasia, and 3 with normal foveolar/glandular (F/G) index. None showed either lymphocytic gastritis or CMV inclusions. Three CAPG cases were associated with gastric carcinoma. The F/G index was less than 1 in all controls. Eleven out of the 12 cases with CAPG showed amplification for CMV DNA while all controls were negative. Findings suggest a very close association, probably in progressive stages, between CMV infection, CAPG, foveolar hyperplasia (with or without Ménétrier disease) and gastric carcinoma. CAPG might be a histologic marker for CMV infection in the germinative zone of the neck of gastric glands. These findings resemble those of hepatitis B virus (HBV) infection, chronic hepatitis, cirrhosis, and hepatocellular carcinoma saga. 相似文献
89.
Jurriaan P Oudhoff Danielle RM Timmermans Martin Rietberg Dirk L Knol Gerrit van der Wal 《BMC health services research》2007,7(1):32
Background
Problematic waiting lists in public health care threaten the equity and timeliness of care provision in several countries. This study assesses different stakeholders' views on the acceptability of waiting lists in health care, their preferences for priority care of patients, and their judgements on acceptable waiting times for surgical patients. 相似文献90.
目的:评估人工流产(指手术流产)对乳腺癌危险性的可能影响。方法:研究在上海267040例妇女的一项乳房自我检查随机试验的队列人群中进行,由队列研究和巢式病例对照研究两部分组成。结果:依据基线调查表采集的资料分析,人工流产不增加乳腺癌危险性。调整潜在的混淆因素后,OR=1.06(95%CI:0.91~1.25)。人工流产次数增加无危险性趋势增加。从更详细的652例乳腺癌病例和694例对照资料分析,得出相似的结果。人工流产发生在首次生育后不增加危险性;少数妇女在首次生育前人工流产以及妊娠13周后人工流产,虽然被观察到危险性有增加,但无显著性统计学意义。结论:在中国,人工流产不是乳腺癌发生的重要原因。 相似文献