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151.
G. Pachón‐Peña G. Yu A. Tucker X. Wu J. Vendrell B.A. Bunnell J.M. Gimble 《Journal of cellular physiology》2011,226(3):843-851
Adipose tissue is composed of lipid‐filled mature adipocytes and a heterogeneous stromal vascular fraction (SVF) population of cells. Similarly, the bone marrow (BM) is composed of multiple cell types including adipocytes, hematopoietic, osteoprogenitor, and stromal cells necessary to support hematopoiesis. Both adipose and BM contain a population of mesenchymal stromal/stem cells with the potential to differentiate into multiple lineages, including adipogenic, chondrogenic, and osteogenic cells, depending on the culture conditions. In this study we have shown that human adipose‐derived stem cells (ASCs) and bone marrow mesenchymal stem cells (BMSCs) populations display a common expression profile for many surface antigens, including CD29, CD49c, CD147, CD166, and HLA‐abc. Nevertheless, significant differences were noted in the expression of CD34 and its related protein, PODXL, CD36, CD 49f, CD106, and CD146. Furthermore, ASCs displayed more pronounced adipogenic differentiation capability relative to BMSC based on Oil Red staining (7‐fold vs. 2.85‐fold induction). In contrast, no difference between the stem cell types was detected for osteogenic differentiation based on Alizarin Red staining. Analysis by RT‐PCR demonstrated that both the ASC and BMSC differentiated adipocytes and osteoblast displayed a significant upregulation of lineage‐specific mRNAs relative to the undifferentiated cell populations; no significant differences in fold mRNA induction was noted between ASCs and BMSCs. In conclusion, these results demonstrate human ASCs and BMSCs display distinct immunophenotypes based on surface positivity and expression intensity as well as differences in adipogenic differentiation. The findings support the use of both human ASCs and BMSCs for clinical regenerative medicine. J. Cell. Physiol. 226: 843–851, 2011. © 2010 Wiley‐Liss, Inc. 相似文献
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154.
Bradford N. Bunnell Daniel P. Kenshalo Jr. Paul Czerny Joseph D. Allen 《Primates; journal of primatology》1979,20(2):197-210
The performance of six adult rhesus monkeys on a fixed interval 1-min reinforcement schedule was examined under conditions
where the reinforcement probabilities were either 1.00 or .80. The animals were tested with a reinforcement probability of
1.00 immediately after removal from their social group, tested again several months later with reinforcement probabilities
of 1.00 and .80, and then retested with a reinforcement probability of .80 before, during, and after the formation of a new
social group with the six monkeys.
The results supported an earlier report in which it was found that high ranking animals responded at a lower rate under a
reinforcement probability of 1.00 than did low ranking animals and that the former also had a higher ratio of nonreinforced
to reinforced responses than the lower ranked animals. These relationships were present in five of the six animals immediately
after removal of the animals from their original group and during and after formation of the new group. They did not appear
on tests conducted after the animals had been out of a social group for several months.
A third result was a suppression of operant performance which appeared in all animals following group formation. The magnitude
and duration of this effect was inversely related to social rank and the time the animal had been a member of the group.
The data are discussed in terms of a carry-over of the effects of recent social experience on two factors: a more deliberate
rate of response by higher ranking animals under 100% reinforcement and an inhibition of response bursting following omission
of reinforcement by the lower ranking monkeys.
Supported by USAMRDC Contract No. DADA 17-73-C-3007. 相似文献
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156.
Metal concentrations in the gill, muscle and liver tissues of Labeo rosae from two impoundments, Loskop and Flag Boshielo dams on the Olifants River, were evaluated in 2011 to detect patterns in metal associations between tissues and impoundments. Elevated concentrations of Ba, Zn, B, Al, Si and Fe, relative to a pristine site in the catchment, were found in the muscle, liver and gill tissues at both impoundments. Molybdenum concentrations were exceptionally high in all tissues at Loskop Dam and in liver at Flag Boshielo Dam. No definite pattern in the ratio metal concentrations within, or between, fish tissues was identified. The expected trend, liver > gills > muscle, was found at both impoundments, but was less prominent at Loskop Dam. Metal concentrations in muscle of Loskop Dam fish were significantly higher than in those at Flag Boshielo Dam. The inverse was true for liver. The long-term impact of elevated metal concentrations on fish health at both impoundments raises concern. 相似文献
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158.
Sean D. Madsen Margaret K. Giler Bruce A. Bunnell Kim C. O'Connor 《Biotechnology journal》2021,16(3):2000248
Preclinical animal studies are essential to the development of safe and effective stem cell therapies. Bioluminescence imaging (BLI) is a powerful tool in animal studies that enables the real-time longitudinal monitoring of stem cells in vivo to elucidate their regenerative properties. This review describes the application of BLI in preclinical stem cell research to address critical challenges in producing successful stem cell therapeutics. These challenges include stem cell survival, proliferation, homing, stress response, and differentiation. The applications presented here utilize bioluminescence to investigate a variety of stem and progenitor cells in several different in vivo models of disease and implantation. An overview of luciferase reporters is provided, along with the advantages and disadvantages of BLI. Additionally, BLI is compared to other preclinical imaging modalities and potential future applications of this technology are discussed in emerging areas of stem cell research. 相似文献
159.
The influence of an afternoon bout of exhaustive submaximal exercise on cardiovascular function and catecholamine excretion during sleep was examined in five female and four male subjects. Subjects walked on a treadmill for successive 50-min periods at 50, 60, and 70% maximal O2 consumption, separated by 10-min rest periods. Exercise terminated with volitional exhaustion. Following an adaptation night, electroencephalographic and impedance cardiographic measures were obtained during three successive nights of sleep, with exercise preceding night 3. Relative to the base-line night (night 2), exhaustive exercise resulted in a sustained elevation of heart rate and cardiac output throughout the entire night's sleep. The magnitude of these elevations was unaffected by sleep stage but decreased over the night. The typical pattern of circadian decline in cardiac output was unaltered. However, the decline in heart rate with sleep onset was greater on the exercise night. Changes in impedance dZ/dt and R-Z interval suggested an enhanced myocardial contractility during the first 3 h of sleep postexercise. Analysis of morning urine samples revealed that in seven of nine subjects norepinephrine excretion increased, epinephrine excretion decreased, and dopamine excretion was unchanged during sleep on the exercise night. It is suggested that these cardiac changes reflect a sustained increase in myocardial beta-receptor activity. 相似文献
160.
Robert A. Zampella John F. Bunnell Kim J. Laidig Nicholas A. Procopio 《Ecological Indicators》2006,6(4):644-663
We demonstrate the use of multiple indicators to characterize the ecological integrity of a coastal plain stream system in the New Jersey Pinelands in relation to human-induced watershed alterations. The individual indicators include pH, specific conductance, stream vegetation and stream-fish, impoundment-fish, and anuran assemblages. We evaluate and compare the utility of the individual and multiple environmental and biological indicators and present a relatively straightforward method for ranking sites. Specific conductance and pH measured at 88 monitoring sites varied in relation to the percentage of altered land (developed land and upland agriculture) within the associated watersheds. All three environmental variables were associated with variations in the composition of stream vegetation and stream fish, impoundment fish, and anuran assemblages. With the exception of impoundment fish, the association between altered land and the multiple-indicator scores based on the two water-quality indicators and the four biological indicators was stronger than that displayed by any of the individual variables. 相似文献