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21.
22.
Two hundred twenty-five patients with 358 febrile episodes were treated with tobramycin and ticarcillin (TT), tobramycin and mezlocillin (TM), or tobramycin, ticarcillin and cephalothin (TTC). There were no statistically significant differences in the response rates for patients who were proven to have infection (67% with TT, 69% with TTC and 53% with TM). Patients were more often cured of their infection if their neutrophil count rose during therapy. In this study, the addition of cephalothin to TT did not increase the frequency of azotemia (10% and 12%, respectively). Although mezlocillin has a broader spectrum of activity in vitro than ticarcillin, it was not more efficacious when combined with tobramycin than ticarcillin plus tobramycin for the treatment of infections in neutropenic patients.  相似文献   
23.
The lymphoma cell line LSTRA contains an elevated level of tyrosine protein kinase activity. It has been suggested that this elevated level of activity is due to the presence of a phosphoprotein with a molecular weight of 56,000 (pp56, formerly referred to as a 58,000-dalton protein). This paper describes the preparation of antibodies against pp56 through the use of a synthetic peptide that contains the sequence around the site of tyrosine phosphorylation in pp56, which is identical to the phosphorylation site in pp60src. These antipeptide antibodies specifically immunoprecipitated 32P-labeled pp56 from detergent extracts of LSTRA cells. In immunoblotting experiments, pp56 was the major antigen detected in the particulate fraction from LSTRA cells by the antipeptide antibodies. The antibodies were also used to show that the level of pp56 is greatly elevated in LSTRA cells. Incubation of the detergent extract of the particulate fraction from LSTRA cells with the antipeptide antibodies resulted in inhibition of most of the LSTRA cell tyrosine protein kinase activity. These results indicate that pp56 is the tyrosine protein kinase whose activity is elevated in LSTRA cells. This enzyme may be a member of the large family of protein kinases involved in the regulation of cell growth.  相似文献   
24.
Recent OPTN proposals to address geographic disparity in liver allocation have involved circular boundaries: the policy selected 12/17 allocated to 150‐mile circles in addition to DSAs/regions, and the policy selected 12/18 allocated to 150‐mile circles eliminating DSA/region boundaries. However, methods to reduce geographic disparity remain controversial, within the OPTN and the transplant community. To inform ongoing discussions, we studied center‐level supply/demand ratios using SRTR data (07/2013‐06/2017) for 27 334 transplanted deceased donor livers and 44 652 incident waitlist candidates. Supply was the number of donors from an allocation unit (DSA or circle), allocated proportionally (by waitlist size) to the centers drawing on these donors. We measured geographic disparity as variance in log‐transformed supply/demand ratio, comparing allocation based on DSAs, fixed‐distance circles (150‐ or 400‐mile radius), and fixed‐population (12‐ or 50‐million) circles. The recently proposed 150‐mile radius circles (variance = 0.11, P = .9) or 12‐million‐population circles (variance = 0.08, P = .1) did not reduce the geographic disparity compared to DSA‐based allocation (variance = 0.11). However, geographic disparity decreased substantially to 0.02 in both larger fixed‐distance (400‐mile, P < .001) and larger fixed‐population (50‐million, P < .001) circles (P = .9 comparing fixed distance and fixed population). For allocation circles to reduce geographic disparities, they must be larger than a 150‐mile radius; additionally, fixed‐population circles are not superior to fixed‐distance circles.  相似文献   
25.
Under Share 35, deceased donor (DD) livers are offered regionally to candidates with Model for End‐Stage Liver Disease (MELD) scores ≥35 before being offered locally to candidates with MELD scores <35. Using Scientific Registry of Transplant Recipients data from June 2013 to June 2015, we identified 1768 DD livers exported to regional candidates with MELD scores ≥35 who were transplanted at a median MELD score of 39 (interquartile range [IQR] 37–40) with 30‐day posttransplant survival of 96%. In total, 1764 (99.8%) exports had an ABO‐compatible candidate in the recovering organ procurement organization (OPO), representing 1219 unique reprioritized candidates who would have had priority over the regional candidate under pre–Share 35 allocation. Reprioritized candidates had a median waitlist MELD score of 31 (IQR 27–34) when the liver was exported. Overall, 291 (24%) reprioritized candidates had a comparable MELD score (within 3 points of the regional recipient), and 209 (72%) were eventually transplanted in 11 days (IQR 3–38 days) using a local (50%), regional (50%) or national (<1%) liver; 60 (21%) died, 13 (4.5%) remained on the waitlist and nine (3.1%) were removed for other reasons. Of those eventually transplanted, MELD score did not increase in 57%; it increased by 1–3 points in 37% and by ≥4 points in 5.7% after the export. In three cases, OPOs exchanged regional exports within a 24‐h window. The majority of comparable reprioritized candidates were not disadvantaged; however, 21% died after an export.  相似文献   
26.
While kidney paired donation (KPD) enables the utilization of living donor kidneys from healthy and willing donors incompatible with their intended recipients, the strategy poses complex challenges that have limited its adoption in United States and Canada. A consensus conference was convened March 29–30, 2012 to address the dynamic challenges and complexities of KPD that inhibit optimal implementation. Stakeholders considered donor evaluation and care, histocompatibility testing, allocation algorithms, financing, geographic challenges and implementation strategies with the goal to safely maximize KPD at every transplant center. Best practices, knowledge gaps and research goals were identified and summarized in this document.  相似文献   
27.
In June 2013, a change to the liver waitlist priority algorithm was implemented. Under Share 35, regional candidates with MELD ≥ 35 receive higher priority than local candidates with MELD < 35. We compared liver distribution and mortality in the first 12 months of Share 35 to an equivalent time period before. Under Share 35, new listings with MELD ≥ 35 increased slightly from 752 (9.2% of listings) to 820 (9.7%, p = 0.3), but the proportion of deceased‐donor liver transplants (DDLTs) allocated to recipients with MELD ≥ 35 increased from 23.1% to 30.1% (p < 0.001). The proportion of regional shares increased from 18.9% to 30.4% (p < 0.001). Sharing of exports was less clustered among a handful of centers (Gini coefficient decreased from 0.49 to 0.34), but there was no evidence of change in CIT (p = 0.8). Total adult DDLT volume increased from 4133 to 4369, and adjusted odds of discard decreased by 14% (p = 0.03). Waitlist mortality decreased by 30% among patients with baseline MELD > 30 (SHR = 0.70, p < 0.001) with no change for patients with lower baseline MELD (p = 0.9). Posttransplant length‐of‐stay (p = 0.2) and posttransplant mortality (p = 0.9) remained unchanged. In the first 12 months, Share 35 was associated with more transplants, fewer discards, and lower waitlist mortality, but not at the expense of CIT or early posttransplant outcomes.  相似文献   
28.

Background  

Ablation of the left atrium and pulmonary veins antrum (PVAI) can be an effective treatment of atrial fibrillation (AF). However, there is discrepancy in the literature regarding the effect extensive ablation has on left atrial (LA) function. We sought to evaluate the effect that AF ablation procedures has on global and regional wall motion as assessed by cardiovascular magnetic resonance imaging (MRI).  相似文献   
29.
Gastric bypass for morbid obesity: a medical--surgical assessment.   总被引:3,自引:2,他引:1       下载免费PDF全文
With the operative modifications and dietary guidelines described in this report, death and complications from gastric bypass were minimal, and weight loss was marked. Ninety per cent of a group of 69 patients lost more than half of their excess weight within the first two years after operation. Stringent preselection of patients for operation was crucial to the success of the operation, and marked alterations of eating behavior was necessary to achieve the weight loss. Mild electrolyte deficiencies and hypovitaminosis occurred in up to one-fourth of the patients. While none of these abnormalities was harmful to the patients, and all were easily corrected, their occurrence demonstrates the importance of long-term follow-up after the operation. We conclude that gastric bypass, with a 50-60 cc pouch and a small (1-1.2 cm) gastrojejunostomy, remains the operation of choice for morbid obesity.  相似文献   
30.
A captive colony of male sea lions (Zalophus californianus) living in northern California shows an annual weight fluctuation related to their reproductive season. Seasonal fattening, which is associated with an increase in territorial displays, starts developing at 5 years of age, when a sagittal crest first becomes apparent, and becomes more prominent as the males reach full maturity.  相似文献   
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