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尖叶清风藤化学成分的研究   总被引:6,自引:0,他引:6  
从尖叶清风藤(Sabia swinhoei Hmsl.exForb.etHemsl.)的地上部分分离出8个化合物,经理化常数测定和光谱解析,证明其中2个为新成分,分别命名为清风藤内酯(I)和清风藤酮(II),另外6个为已知化合物,即没药烯(III)、三十烷醇(IV)、β-谷甾醇(V)、二十八烷酸(VI)、齐墩果酸(VII)和胡萝卜甙(VIII)。  相似文献   
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南蛇藤素抑制豚鼠体外精子的受精能力   总被引:9,自引:0,他引:9  
南蛇藤素(Cel)对豚鼠精子前向运动(FM)、获能(Cap)、顶体反应(AR)和穿透去透明带仓鼠卵(SPA)均有明显的抑制作用,其作用强度随剂量而增加;对Cel的敏感性依次为精子Cap>FM>SPA>AR。Cel对豚鼠精子AR,FM和Cap的抑制作用比乙酸棉酚(GA)明显为强。  相似文献   
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Background

An important factor contributing to the high mortality in patients with severe head trauma is cerebral hypoxia. The mechanical ventilation helps both by reduction in the intracranial pressure and hypoxia. Ventilatory support is also required in these patients because of patient's inability to protect the airway, persistence of excessive secretions, and inadequacy of spontaneous ventilation. Prolonged endotracheal intubation is however associated with trauma to the larynx, trachea, and patient discomfort in addition to requirement of sedatives. Tracheostomy has been found to play an integral role in the airway management of such patients, but its timing remains subject to considerable practice variation. In a developing country like India where the intensive care facilities are scarce and rarely available, these critical patients have to be managed in high dependency cubicles in the ward, often with inadequately trained nursing staff and equipment to monitor them. An early tracheostomy in the selected group of patients based on Glasgow Coma Score(GCS) may prove to be life saving.Against this background a prospective study was contemplated to assess the role of early tracheostomy in patients with isolated closed head injury.

Methods

The series consisted of a cohort of 50 patients admitted to the surgical emergency with isolated closed head injury, that were not considered for surgery by the neuro-surgeon or shifted to ICU, but had GCS score of less than 8 and SAPS II score of more than 50. First 50 case records from January 2001 that fulfilled the criteria constituted the control group. The patients were managed as per ATLS protocol and intubated if required at any time before decision to perform tracheostomy was taken. These patients were serially assessed for GCS (worst score of the day as calculated by senior surgical resident) and SAPS scores till day 15 to chart any changes in their status of head injuries and predictive mortality. Those patients who continued to have a GCS score of <8 and SAPS score of >50 for more than 24 hours (to rule out concussion or recovery) underwent tracheostomy. All these patients were finally assessed for mortality rate and hospital stay, the statistical analysis was carried out using SPSS10 version. The final outcome (in terms of mortality) was analyzed utilizing chi-square test and p value <0.05 was considered significant.

Results

At admission both tracheostomy and non-tracheostomy groups were matched with respect to GCS score and SAPS score. The average day of tracheostomy was 2.18 ± 1.0038 days. The GCS scores on days 1, 2, 3, 4, 5, 10 between tracheostomy and non-tracheostomized group were comparable. However the difference in the GCS scores was statistically significant on day 15 being higher in the tracheostomy group.Thus early tracheostomy was observed to improve the mortality rate significantly in patients with isolated closed head injury

Conclusion

It may be concluded that early tracheostomy is beneficial in patients with isolated closed head injury which is severe enough to affect systemic physiological parameters, in terms of decreased mortality and intubation associated complications in centers where ICU care is not readily available. Also, in a selected group of patients, early tracheostomy may do away with the need for prolonged mechanical ventilation.  相似文献   
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Platelets are known to become activated during storage, but it is unclear whether such activation affects recovery or survival after platelet concentrate (PC) transfusion. With the use of flow cytometry to determine the percentage of platelets expressing the alpha-granule membrane protein 140 (GMP-140), a known adhesive ligand appearing on the platelet surface after activation, several studies were conducted. These investigations evaluated 1) the occurrence of significant platelet activation over time in PCs (n = 46) stored under standard blood bank conditions; 2) the correlation between platelet activation and platelet recovery in normal subjects after PC storage (n = 12), as assessed by the recovery of Indium-labeled platelets; and 3) the recovery of activated and unactivated platelets in thrombocytopenic cancer patients transfused with standard PCs (n = 11). It was determined 1) that an increasing duration of storage of PC was associated with increasing platelet activation as measured by the percentage of platelets expressing GMP-140, progressing from a mean of 4 +/- 2 percent (SD) on the day of collection to a mean of 25 +/- 8 percent by 5 days of storage: 2) that, in normal subjects, posttransfusion recovery of autologous platelets stored for 2 to 4 days and then labeled with In111 was inversely correlated with the percentage of activated platelets in the transfused PC (r = -0.55, p = 0.05); and 3) that, when thrombocytopenic patients were transfused with standard PCs, the recovery of the activated platelets in the transfused PCs averaged only 38 +/- 15 percent of the number predicted by the absolute platelet increment.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
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