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81.
82.
A girl with multiple anomalies was found to have trisomy 14 mosaicism. The physical findings in reported cases indicate the condition is a recognizable syndrome.  相似文献   
83.
Swayne  LC 《Radiology》1986,160(1):33-38
Forty-one proved cases of acute acalculous cholecystitis imaged with technetium-99m iminodiacetic acid (IDA) cholescintigraphy were retrospectively analyzed. After the exclusion of one indeterminate scan (showing poor initial hepatic uptake and excretion), the study yielded a 92.5% (37 of 40) sensitivity for the detection of cystic or common bile duct obstruction. Each of the three patients with false-negative scintigrams had other abnormal scintigraphic findings suggestive of biliary tract disease. Of the 20 patients (48.8%) with focal or diffuse gangrenous cholecystitis or perforation, seven (35%) exhibited either free peritoneal spill or increased pericholecystic activity to indicate the presence of advanced disease.  相似文献   
84.
Phototropism in the fungus Phycomyces is mediated by two photosystems that are optimized for the low-intensity region (below 10(-6) W X m-2) and the high-intensity region (above 10(-6) W X m-2). These photosystems can be distinguished under special experimental conditions, in which sporangiophores grown in the dark are suddenly exposed to continuous unilateral light. With this treatment, the bending occurs in two steps. Below 10(-6) W X m-2, an early-response component (15-min latency) and a late-response component (50- to 70-min latency) are observed that are mediated by photosystem I. Above 10(-6) W X m-2, the early component is augmented by an intermediate component with a 40-min delay that is mediated by photosystem II. The two photosystems are distinguished further by their wavelength sensitivities and adaptation kinetics. Photosystem I is more effective at 334, 347, and 550 nm than photosystem II, but it is less effective at 383 nm. At wavelength 450 nm, the dark-adaptation kinetics associated with photosystem I are approximately half as fast as those associated with photosystem II. However, the light-adaptation kinetics of photosystem I are approximately equal to 3 times faster than the kinetics associated with photosystem II. The existence of two photosystems clarifies several behavioral features of Phycomyces and helps explain how the sporangiophore can manage the full range of 10 decades.  相似文献   
85.
BACKGROUND: Two large research projects funded by the National Institutes of Health, the Disease Management project and the Thrive study, which examine different phenomena in the chronically critically ill population, have combined research teams. Each study has its own project manager and maintains a separate database and budget. Operational tasks for both grants are streamlined through the collaboration and cross-training of all team members. METHODS: The Disease Management project is a randomized clinical trial testing the effectiveness of a care program in improving outcomes for chronically critically ill patients and their caregivers during the first 2 months after discharge. The Thrive study is a prospective longitudinal investigation that aims to describe the weaning patterns of chronically critically ill patients as well as the patterns of illness-related variables. RESULTS: To date, many participants (n = 400) have been enrolled in each study. The results of both studies will be available through future publications. CONCLUSIONS: Although much information has been gleaned from gathering longitudinal data across one study population and examining two rich data sets, there are some limitations to this collaboration.  相似文献   
86.
目的:为获得组织工程化自体血管,观察体外静态培养条件下犬内皮细胞与平滑肌细胞联合培养组织学及形态学的特征。方法:实验于2004-07/2005-06在首都医科大学宣武医院外科院级实验室完成。①实验材料:雄性杂种犬,3个月龄,体质量8~12kg。②实验方法:贴块法及酶解法对犬内皮细胞及平滑肌细胞进行原代分离培养及扩增,将第Ⅱ代平滑肌细胞以1×109L-1的密度种植于胶原膜上培养13d,再将第Ⅱ代内皮细胞接种于生长平滑肌细胞的胶原膜上2d。③实验评估:行苏木精-伊红染色同时扫描电镜和透射电镜观察平滑肌细胞和内皮细胞在胶原载体上联合培养后的形态。结果:苏木精-伊红染色见平滑肌细胞较均匀的分布于支架材料表面及内部;扫描电镜下,平滑肌细胞可以在胶原载体材料上生长,增殖明显并在短期内形成多层细胞。内皮细胞与平滑肌细胞联合培养2d就可在平滑肌细胞层表面获得连续的单层内皮细胞层。结论:在短期静态培养条件下犬的血管平滑肌细胞和内皮细胞可以在胶原载体材料上形成具有两层细胞结构的组织工程化动脉血管组织片。  相似文献   
87.
The hepatocyte growth factor/scatter factor (HGF/SF) receptor, Met, mediates various cellular responses on activation with its ligand, including proliferation, survival, motility, invasion, and tubular morphogenesis. Met expression is frequently up-regulated in sarcomas and carcinomas. Experimental evidence suggests that Met activation correlates with poor clinical outcome and the likelihood of metastasis. Therefore, inhibitors of Met tyrosine kinase may be useful for the treatment of a wide variety of cancers that have spread from the primary site. We have discovered potent and selective pyrrole-indolinone Met kinase inhibitors and characterized them for their ability to inhibit HGF/SF-induced cellular responses in vitro. These compounds inhibit HGF/SF-induced receptor phosphorylation in a dose-dependent manner. They also inhibit the HGF/SF-induced motility and invasion of epithelial and carcinoma cells. Therefore, these compounds represent a class of prototype small molecules that selectively inhibit the Met kinase and could lead to identification of compounds with potential therapeutic utility in treatment of cancers.  相似文献   
88.

Introduction

We report the results of the first direct comparison of the once-daily fixed-dose long-acting muscarinic antagonist/long-acting β2-agonist (LAMA/LABA) combinations umeclidinium/vilanterol (UMEC/VI) and tiotropium/olodaterol (TIO/OLO) in patients with COPD.

Methods

This was a randomized, two-period crossover open-label study in symptomatic patients with COPD [age 40 years or older, postbronchodilator forced expiratory volume in 1 s (FEV1) of 70% or less and 50% or more of predicted normal values, and modified Medical Research Council Dyspnoea Scale score of 2 or greater] not receiving inhaled corticosteroid therapy. Patients were randomized to receive UMEC/VI (62.5/25 µg once daily) via a multidose dry powder inhaler (ELLIPTA) followed by TIO/OLO (5/5 µg once daily) via a soft mist inhaler (Respimat), each for 8 weeks with an interim 3-week washout or vice versa. The primary end point was the change from baseline in trough FEV1 at week 8 with a noninferiority margin of ? 50 mL in the per-protocol (PP) population. The incidence of adverse events was also assessed.

Results

In total, 236 patients (mean age 64.4 years, 60% male) were included in the intent-to-treat population and 227 were included in the PP population. UMEC/VI treatment was noninferior in the PP population and superior in the intent-to-treat population to TIO/OLO treatment with regard to trough FEV1 at week 8 [FEV1 change from baseline 180 mL vs 128 mL; difference 52 mL (95% confidence interval 28–77 mL); p < 0.001]. Patients receiving UMEC/VI had twofold increased odds of experiencing a clinically meaningful increase (100 mL or more) from baseline in trough FEV1 at week 8 compared with patients receiving TIO/OLO (odds ratio 2.05; 95% confidence interval 1.34–3.14). Adverse events occurred in 25% of patients in the UMEC/VI group and in 31% of patients in the TIO/OLO group.

Conclusion

In this first direct comparison of two once-daily fixed-dose LAMA/LABA combinations, superiority was observed for the primary end point of trough FEV1 at week 8 with UMEC/VI compared with TIO/OLO in patients with symptomatic COPD. Both treatments had similar safety profiles. These findings confirm the results of previous indirect LAMA/LABA comparisons, and show that an efficacy gradient exists within the LAMA/LABA class.

Trial Registration

ClinicalTrials.gov identifier NCT02799784.

Funding

GlaxoSmithKline.
  相似文献   
89.
BACKGROUND: Epitopes of blood group A antigen can be enzymatically cleaved from red cells (RBCs), but the extent of cleavage required for normal survival in allogeneic blood transfusion recipients is unknown. Therefore, the cleavage rates were studied for A antigen epitope binding of 1) complement-activating anti-A, 2) Dolichos biflorus anti- A, lectin, and 3) hemagglutinating anti-A during incubation with a purified alpha-N-acetylgalactosaminidase, E.C. 3.2.1.49 (alpha- GalNAc'ase). STUDY DESIGN AND METHODS: Suspensions of group A RBCs were incubated with alpha-GalNAc'ase. Cells were removed at intervals, washed, and tested for loss of binding by monoclonal, polyclonal, and complement-activating anti-A, D. biflorus anti-A1 lectin, and Ulex europaeus anti-H lectin. RESULTS: A epitopes binding D. biflorus lectin were highly susceptible to alpha-GalNAc'ase; simultaneously with their loss, binding with U. europaeus lectin emerged. Loss of complement- mediated hemolysis was slower. A epitopes binding hemagglutinating anti- A were most resistant. Cleavage of A epitopes from membrane glycosphingolipids with short oligosaccharide chains was similarly resistant. Rates of cleavage from A1 and A2 RBCs were similar. CONCLUSION: RBC epitopes of blood group A differ in susceptibility to cleavage and biologic reactivity, which suggests that subsets mediating important biologic functions exist on functionally and topographically distinct membrane glycoconjugates.  相似文献   
90.
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