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41.
A substance produced by various types of cells can induce from single hematopoietic cells the formation of colonies of normal macrophages and granulocytes. This inducer has been purified 600-fold from serum-free conditioned medium from a tissue culture line of mouse cells. It is shown that the inducer is a protein, with a molecular weight of 65-70,000, whose inducing activity was about 1 ng per colony. Acrylamide gel electrophoresis of this material gave four bands, only one of which contained inducing activity. The purified protein was inactive. Activity was regained by the addition of a low molecular weight cofactor that is present in conditioned medium. Under certain conditions, activity was also regained by the addition of adenosine 3':5'-cyclic monophosphate (cyclic AMP).  相似文献   
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Objective

To test the effectiveness and acceptability of an outpatient medical abortion protocol with 200 mg mifepristone and 400 mcg sublingual misoprostol at 64–70 days' last menstrual period (LMP) and compare it to the already known efficacy of the 57–63 days' LMP gestational age range.

Study Design

We conducted a prospective, comparative open-label trial in six hospitals and clinics in Ukraine, Georgia, India and Tunisia. We enrolled 714 reproductive age women with pregnancies 57 to 70 days who presented requesting abortion. Medical abortions were managed with the current service delivery protocol (200 mg oral mifepristone followed in 24–48 h by 400 mcg sublingual misoprostol). Data on safety, efficacy and acceptability were collected. The main outcome measure was complete abortion without surgical intervention at any point.

Results

A total of 703 cases were analyzable for efficacy. Success rates did not differ significantly in the two groups [57–63-day group: 94·8%; 64–70-day group: 91.9%; Relative Risk (RR): 0.79 (0.61–1.04)]. Ongoing pregnancy rates also did not differ significantly (57–63 days: 1.8%; 64–70 days: 2.2%; RR: 1.10 (0.65–1.87)].

Conclusion

A medical abortion regimen of 200 mg mifepristone followed in 24–48 h by 400 mcg sublingual misoprostol is effective through 70 days' gestation and may be offered within existing outpatient abortion services.

Implications

A regimen of 200 mg mifepristone followed in 24–48 h by 400 mcg sublingual misoprostol is effective up to 70 days' LMP. The findings have important implications for expanding access to outpatient medical abortion services in settings where the cost of misoprostol is of concern or a two-pill misoprostol regimen is the standard of care.  相似文献   
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Ricin, one of the most potent and lethal toxins known, is classified by the Centers for Disease Control and Prevention (CDC) as a select agent. Currently, there is no available antidote against ricin exposure, and the most promising therapy is based on neutralizing antibodies elicited by active vaccination or that are given passively. The aim of this study was to characterize the repertoire of anti-ricin antibodies generated in rabbits immunized with ricin toxoid. These anti-ricin antibodies exhibit an exceptionally high avidity (thiocyanate-based avidity index, 9 M) toward ricin and an apparent affinity of 1 nM. Utilizing a novel tissue culture-based assay that enables the determination of ricin activity within a short time period, we found that the anti-ricin antibodies also possess a very high neutralizing titer. In line with these findings, these antibodies conferred mice with full protection against pulmonary ricinosis when administered as a passive vaccination. Epitope mapping analysis using phage display random peptide libraries revealed that the polyclonal serum contains four immunodominant epitopes, three of which are located on the A subunit and one on the B subunit of ricin. Only two of the four epitopes were found to have a significant role in ricin neutralization. To the best of our knowledge, this is the first work that characterizes these immunological aspects of the polyclonal response to ricin holotoxin-based vaccination. These findings provide useful information and a possible strategy for the development and design of an improved ricin holotoxin-based vaccine.  相似文献   
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Aim: We assess the accuracy of torque controllers after several aging processes and the bacterial leakage on implant-abutment complexes (IAC). Methods: A total of 12 spring-type and 12 friction-type torque controllers and 48 IAC (24 conical and 24 hexagonal connections) were evaluated. Chemical, mechanical, temperature, and pressure-aging methods were applied individually to replicate clinical use. Torque controller accuracy was analyzed before and after aging using a calibrated gauge. To assess bacterial leakage, the IAC were suspended in a bacterial medium for 24 h. Direct Contact Test (DCT) and Polymerase Chain Reaction Test (RT-PCR) analyzed the infiltration of F. nucleatum and P. gingivalis into the IAC micro-gap. Results: A significant decrease in torque after 10 days of aging was found. The spring-type torque controller was affected the most, regardless of the aging method (P < 0.05). PCR results indicated that all groups exhibited significantly more bacterial leakage, regardless of the method used (P < 0.05). The conical IAC demonstrated more bacterial leakage of P. gingivalis compared with the hexagonal IAC (P = 0.07). DCT found bacterial growth in the IAC only before aging and was not identified after aging. Conclusion: Aging affects torque accuracy. A reduction in force was noticed after 10 days. The conical IAC exhibits more bacterial leakage, although this was not statistically significant.  相似文献   
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The Cerebellum - During evolution, living systems, actively interacting with their environment, developed the ability, through sensorimotor contingencies, to construct functional spaces shaping...  相似文献   
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Neurodegenerative disorders are characterized by disruptions to neuronal function and circuitry,leading to a variety of clinical syndromes depending on the affected neuroanatomic regions(Geula,1998).Many proteinopathies implicated in neurodegenerative diseases are characterized by the pathologic accumulation of proteins into inclusions that are initially deposited in specific areas of the brain and spread widely with disease progression.  相似文献   
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