全文获取类型
收费全文 | 231篇 |
免费 | 9篇 |
出版年
2023年 | 1篇 |
2022年 | 7篇 |
2021年 | 10篇 |
2020年 | 7篇 |
2019年 | 5篇 |
2018年 | 8篇 |
2017年 | 4篇 |
2016年 | 7篇 |
2015年 | 12篇 |
2014年 | 10篇 |
2013年 | 19篇 |
2012年 | 24篇 |
2011年 | 15篇 |
2010年 | 13篇 |
2009年 | 5篇 |
2008年 | 10篇 |
2007年 | 12篇 |
2006年 | 15篇 |
2005年 | 11篇 |
2004年 | 7篇 |
2003年 | 7篇 |
2002年 | 4篇 |
2001年 | 3篇 |
2000年 | 1篇 |
1999年 | 2篇 |
1996年 | 1篇 |
1994年 | 1篇 |
1993年 | 1篇 |
1992年 | 2篇 |
1987年 | 3篇 |
1984年 | 1篇 |
1983年 | 1篇 |
1980年 | 2篇 |
1979年 | 1篇 |
1978年 | 1篇 |
1977年 | 1篇 |
1976年 | 2篇 |
1975年 | 1篇 |
1974年 | 1篇 |
1972年 | 1篇 |
1969年 | 1篇 |
排序方式: 共有240条查询结果,搜索用时 562 毫秒
231.
232.
Md Habibullah BAHAR Mahmud AL PARVEZ Saidur RAHMAN Rejaul ISLAM 《Entomological Research》2011,41(2):46-52
Five cultivated mulberry plant varieties, BSRM‐34, BSRM‐56, BSRM‐57, BSRM‐58 and BSRM‐59, were used to evaluate the effects of plant variety on larval and cocoon characteristics of mulberry silkworm Bombyx mori L. Silkworm larvae undergo their entire larval periods on leaves of mulberry varieties. Different larval characteristics of larval weight, larval length and larval breadth were measured in different growth stages. After rearing, the fifth instar larvae were transferred into a mountage (Chandraki) structure for cocoon rearing for spinning and cocoon production. The cocoons were then harvested and different cocoon characteristics like cocoon weight, shell weight and shell percentage; and other characters like pupal weight and effective rate of rearing were measured. The results showed statistically significant differences among different varieties on larval and cocoon characteristics. The highest performance was observed by feeding the variety BSRM‐34 in respect of the average weight of 10 mature larvae (40.5 g), single mature larval length (7.6 cm) and breadth (1.0 cm), single cocoon weight (1.4 g), shell weight (0.2 g) and pupal weight (1.2 g) while the average performance was recorded by feeding varieties BSRM‐57 and BSRM‐59. The poorest performance was showed by feeding the variety BSRM‐56 (in case of larval characters) and BSRM‐58 (in case of cocoon characteristics). These two varieties also showed the poorest performance for silk yield. Through comparing all the above parameters it was concluded that BSRM‐34 is the best mulberry variety and it is recommended that Bangladeshi farmers adopt that variety for better yield of silk. 相似文献
233.
234.
235.
Mahmud Bani-Yaghoub Roger G Tremblay Abdellah Ajji Munyao Nzau Sandhya Gangaraju David Chitty Bogdan Zurakowski Marianna Sikorska 《Biochimie et biologie cellulaire》2008,86(5):361-369
Every year thousands of people suffer from brain injuries and stroke, and develop motor, sensory, and cognitive problems as a result of neuronal loss in the brain. Unfortunately, the damaged brain has a limited ability to enact repair and current modes of treatment are not sufficient to offset the damage. An extensive list of growth factors, neurotrophic factors, cytokines, and drugs has been explored as potential therapies. However, only a limited number of them may actually have the potential to effectively offset the brain injury or stroke-related problems. One of the treatments considered for future brain repair is bone morphogenetic protein 7 (BMP7), a factor currently used in patients to treat non-neurological diseases. The clinical application of BMP7 is based on its neuroprotective role in stroke animal models. This paper reviews the current approaches considered for brain repair and discusses the novel convergent strategies by which BMP7 potentially can induce neuroregeneration. 相似文献
236.
237.
Faruque Md. Omar Al Mahmud Rabiul Sagor Rakibul Hasan 《Plasmonics (Norwell, Mass.)》2022,17(1):203-211
Plasmonics - Metal–Insulator-Metal (MIM) structures possess a number of shortcomings which include optical loss, tenability, nanofabrication challenges, chemical instability, incompatible... 相似文献
238.
239.
F. S. Mahmud 《Entomologia Experimentalis et Applicata》1980,28(1):47-53
Environmental and genetic factors which influence alary polymorphism in Laodelphax striatellus (Fallén) were studied. It has been found that alary polymorphism in L. striatellus is determined by quality and quantity of food, and crowding. There is also a clear genetic basis for polymorphism.
Zusammenfassung In dieser Studie werden einige Umweltfaktoren und genetische Faktoren untersucht, welche den Flügelpolymorphismus bei Laodelphax striatellus (Fallén) beeinflussen. Es wurde festgestellt, dass verschiedene Umweltfaktoren wie Qualität und Quantität des Futters und Crowding bestimmend wirken. Es besteht auch eine klare genetische Basis für Polymorphismus.相似文献
240.
Mícheál de Barra Lisa M. DeBruine Benedict C. Jones Zahid Hayat Mahmud Valerie A. Curtis 《Evolution and human behavior》2013,34(6):384-389
The value of different mate choices may depend on the local pathogen ecology and on personal infection susceptibility: when there is a high risk of infection, choosing a healthy or immunocompetent mate may be particularly important. Frequency of childhood illness may act as a cue of the ecological and immunological factors relevant to mate preferences. Consistent with this proposal, we found that childhood illness – and frequency of diarrhea in particular – was positively correlated with preferences for exaggerated sex-typical characteristics in opposite-sex, but not same-sex, faces. Moreover, this relationship was stronger among individuals with poorer current health. These data suggest that childhood illness may play a role in calibrating adult mate preferences and have implications for theories of disease-avoidance psychology, life-history strategy and cross-cultural differences in mate preferences. 相似文献