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1.
Chemotactic inhibitors in sera of patients with neoplastic disease   总被引:1,自引:0,他引:1  
Our objective was to define the functional characteristics of chemotactic inhibitors in sera of patients with various neoplastic diseases. Fifty-nine patients were studied: lung cancer (15), breast cancer (11), lymphoma (20), leukemia (13). Chemotaxis and random motility were measured using a modified agarose technique with C5a and a bacterial filtrate of E. coli as the chemoattractants. Two types of inhibitors were found: chemotactic factor inhibitors and cell-directed inhibitors. The type of inhibitor as well as the specificity of the inhibitor for the chemoattractant (C5a or bacterial filtrate) varied depending upon the underlying neoplasm. Cell-directed inhibitors were reversible and none of the inhibitors affected random motility. Contrary to previous reports, the chemotactic factor inhibitors were heat-stable (p less than 0.001). Morphometric analysis of inhibited and non-inhibited cells using scanning electron photomicrographs showed a significant alteration in shape of the inhibited cells (p less than 0.003). The results indicate greater heterogeneity of the chemotactic inhibitors than was previously thought, as well as a tumour-dependent specificity of the inhibitors for the chemoattractants.  相似文献   
2.
People in wheelchairs spend a long time in the sitting position and often incur alignment problems resulting in neck and back pain. This study: (1) assessed the validity/reliability of Coach’s Eye (CE) smart device application, (2) examined the effect of seat to back support angle adjustments on head, neck, and shoulder posture in the sitting position, and (3) compared changes in cervical rotation at each back support angle. Abled subjects sat in a wheelchair with back support angles positioned at 90°, 100°, and 110°. CE, as well as ImageJ software, was used to analyze three angles: sagittal head angle (SHA), cervical angle (CVA), and shoulder angle (SA). There were highly significant differences for CVA and SA (p < 0.001) among the three seat to back support angles. Validity of CE was examined by correlating CE with ImageJ scores. CE had high validity for all angles (r = 0.99, 0.98, 0.99 respectively, p < 0.001). Inter-rater reliability for SHA, CVA, and SA was high (intraclass correlation coefficient [ICC] ranged from 0.95 to 0.99). Head (CVA) and shoulder (SA) alignment was closest to neutral posture with back support angles set at 110° and 90°, respectively.  相似文献   
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The development of hydrogel films as wound healing dressings is of a great interest owing to their biological tissue-like nature. Polyvinyl alcohol/polyethylene glycol (PVA/PEG) hydrogels loaded with asiaticoside, a standardized rich fraction of Centella asiatica, were successfully developed using the freeze–thaw method. Response surface methodology with Box–Behnken experimental design was employed to optimize the hydrogels. The hydrogels were characterized and optimized by gel fraction, swelling behavior, water vapor transmission rate and mechanical strength. The formulation with 8% PVA, 5% PEG 400 and five consecutive freeze–thaw cycles was selected as the optimized formulation and was further characterized by its drug release, rheological study, morphology, cytotoxicity and microbial studies. The optimized formulation showed more than 90% drug release at 12?hours. The rheological properties exhibited that the formulation has viscoelastic behavior and remains stable upon storage. Cell culture studies confirmed the biocompatible nature of the optimized hydrogel formulation. In the microbial limit tests, the optimized hydrogel showed no microbial growth. The developed optimized PVA/PEG hydrogel using freeze–thaw method was swellable, elastic, safe, and it can be considered as a promising new wound dressing formulation.  相似文献   
5.
Interest in tubal assessment is as old as interest in fertility and infertility. The Fallopian tube is a particularly complex structure and, as such, an ideal method for its clinical assessment is very difficult to obtain. As a result, a number of different methods have been suggested. Some of these methods are more complementary to each other rather than potential substitutes for one another. Some have been used for many years with a clear evidence base for their performance as diagnostic tests. For other, relatively new tests, very little evidence about their performance is available. Research is moving from a purely anatomical approach (are the tubes open or blocked?) to encompassing functional enquiry (are the open tubes functional and, if not, are there interventions with which fertility performance can be improved?). The available evidence, or lack thereof, for the most commonly used tubal assessment tests is reviewed in this paper. Many questions remain, which, despite the increasing success of IVF, will continue to challenge and stimulate specialists and the public, who are interested in ways to maximize spontaneous as opposed to assisted fertility.  相似文献   
6.
Recently, a series of case reports and small studies has suggested that births involving assisted reproductive technology (ART) may have an increased risk of imprinting disorders such as Beckwith-Wiedemann syndrome and Angelman syndrome. Herein, the significance and implications of these findings are discussed. It is speculated that, although such imprinting disorders may be shown to be only rare complications of ART, epigenetic errors might account for a much wider spectrum of ART-related complications than is recognized currently. Addressing these questions should be a priority for research on cohorts of ART children.  相似文献   
7.
OBJECTIVE: To determine the expression of apoptosis-associated molecules on cumulus cells removed from individual oocytes of different maturity, inseminated oocytes and to investigate the possibility of an age-dependent expression. DESIGN: Analysis of apoptosis in cumulus cells isolated from oocytes of different stages of maturity. SETTING: Assisted reproductive technology program of the Birmingham Women's Hospital, Birmingham, UK. PATIENT(S): Patients undergoing intracytoplasmic sperm injection or IVF cycles. MAIN OUTCOME MEASURE(S): Percentage of positive cumulus cells when assessed for nuclear DNA damage using the terminal deoxyuridine nucleotide end-labeling assay or stained with antibodies [Fas, Fas ligand, the antiapoptotic protein Bcl-xl, and the RNA-binding protein (TIAR)]. RESULT(S): Cumulus cells collected from mature oocytes showed no significant difference in the percentage of apoptotic markers compared to those recovered from immature oocytes, whereas those from patients >/=38 years differed significantly. When cumulus cells were exposed to sperm the levels of apoptotic markers altered significantly from those not exposed to sperm. CONCLUSION(S): The results show that the cumulus cells of human oocytes are equipped with a mechanism to undergo apoptosis and that patient age and the exposure of cumulus cells to sperm can alter their profiles of apoptotic markers.  相似文献   
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Objective: To demonstrate that particularizing pooled results of a meta-analysis can derive incremental cost effectiveness of superovulation with recombinant follicle-stimulating hormones (rFSH) vs. the highly purified urinary form (uFSH) for assisted conception.

Design: A retrospective study.

Setting: An assisted conception unit in the United Kingdom.

Patient(s): One hundred forty-five fresh in vitro fertilization (IVF) and 58 fresh intracytoplasmic sperm injection (ICSI) cycles.

Intervention(s): rFSH vs. uFSH.

Main Outcome Measure(s): Incremental cost-effectiveness (i.e., cost needed to treat, or CNT) and budget-impact analyses of rFSH vs. uFSH.

Result(s): In women less than 30 years old, the clinical pregnancy rate was 37.7% (95% CI 24.8%–52.1%), the particularized number needed to treat (pNNT) was −19, and the cost needed to treat was £5070.51 (£3660.53 to £7619.32). For the 30- to 35-year-old age group, the clinical pregnancy rate was 29.9% (95% CI 20.0%–41.4%), the particularized number needed to treat was −24, and CNT was £7335.59 (£5284.11 to £10,941.22). For the 36- to 40-year-old age group, the clinical pregnancy rate was 30.6.0% (95% CI 19.6%–43.7%), the particularized number needed to treat was −23.0, and the CNT was £8569.67 (£5998.70 to £13,413.24).

Conclusion(s): The CNT and thus the budget impact analyses (the extra number of cycles that can be funded by the CNT) both increase directly with age of the patient, and inversely with the clinical pregnancy rate.  相似文献   

10.
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