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71.
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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BackgroundOptimal chemotherapy for patients who received cisplatin for localized urothelial carcinoma (UC) and develop metastatic disease is unclear. We compared the efficacy of platinum-based (PBC) versus non–platinum-based (NPBC) first-line chemotherapy for metastasis.Patients and MethodsData were collected from the Retrospective International Study of Cancers of the Urothelial Tract (RISC), a database of 3024 patients from 28 international academic centers from 2005 to 2012. Patient inclusion criteria included: (1) predominant UC; (2) any primary tumor site; (3) cT2-4, cN0-N2, cM0; (4) prior receipt of perioperative/radiation cisplatin-containing chemotherapy; and (5) receipt of cytotoxic chemotherapy in the first-line metastatic setting. Multivariate Cox proportional hazards models were used to show progression-free survival (PFS) and overall survival (OS) from the first day of chemotherapy for metastatic disease to date of censor.ResultsEligibility criteria was met by 132 patients (n = 74 PBC; n = 58 NPBC). The median OS was 8.13 months (interquartile range, 4.87-16.64 months) and 8.77 months (interquartile range, 4.01-13.49 months) for PBC and NPBC, respectively. Neither OS (hazard ratio [HR], 1.04; 95% confidence interval [CI], 0.64-1.69; P = .87) nor PFS (HR, 0.86; 95% CI, 0.56-1.31; P = .48) differed for PBC versus NPBC. However, for patients who received chemotherapy more than a year after perioperative/radiation chemotherapy, OS was superior for PBC over NPBC (HR, 0.31; 95% CI, 0.10-0.92; P = .03).ConclusionsThere is no significant outcome difference between PBC and NPBC in patients with metastatic UC who previously received cisplatin-based chemotherapy for localized disease. However, if over a year has elapsed, return to PBC is associated with superior OS.  相似文献   
75.

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   
76.
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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Epstein–Barr virus (EBV) is a ubiquitous gamma‐herpesvirus that establishes a lifelong persistent infection in the oral cavity and is intermittently shed in the saliva. EBV exhibits a biphasic life cycle, supported by its dual tropism for B lymphocytes and epithelial cells, which allows the virus to be transmitted within oral lymphoid tissues. While infection is often benign, EBV is associated with a number of lymphomas and carcinomas that arise in the oral cavity and at other anatomical sites. Incomplete association of EBV in cancer has questioned if EBV is merely a passenger or a driver of the tumorigenic process. However, the ability of EBV to immortalize B cells and its prevalence in a subset of cancers has implicated EBV as a carcinogenic cofactor in cellular contexts where the viral life cycle is altered. In many cases, EBV likely acts as an agent of tumor progression rather than tumor initiation, conferring malignant phenotypes observed in EBV‐positive cancers. Given that the oral cavity serves as the main site of EBV residence and transmission, here we review the prevalence of EBV in oral malignancies and the mechanisms by which EBV acts as an agent of tumor progression.  相似文献   
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Human PAX2 mutations have been associated with abnormalities in the developing and adult kidney ranging from congenital abnormalities of the kidney and urinary tract (CAKUT) to oncogenic processes. Defining the relationship of PAX2 to human renal disease requires an appreciation of its fundamental role in renal development. Given the highly conserved nature of the PAX2 gene in vertebrates, it is not surprising that much of our understanding of PAX2 involvement in renal disease has been derived from animal models. The following review will outline the current evidence supporting involvement of PAX2 in the pathologic processes involving the kidney.  相似文献   
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