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排序方式: 共有2119条查询结果,搜索用时 15 毫秒
111.
新型冠状病毒肺炎,世界卫生组织命名为"2019冠状病毒病"(corona virus disease 2019,COVID-19),是一种由2019新型冠状病毒(2019-nCov)感染导致的肺炎.目前新冠肺炎在全球广泛流行,且疫情尚未得到全部控制.由于新型冠状病毒表面的刺突蛋白(spike protein,S)介导病...  相似文献   
112.
真菌在中药成分转化中的应用   总被引:3,自引:0,他引:3  
张怡轩 《菌物研究》2006,4(4):77-81
对真菌在中药成分生物转化中的应用取得的进展进行了综述,介绍了真菌的生物转化方法和研究现状。利用真菌对中药成分进行转化是中药高效利用的一条新思路,可显著推动我国的中药资源的高效开发与利用,有利于在短时间内研制出具有自主知识产权的新药。  相似文献   
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The emergence of two different sickle cell disease and disease/treatment paradigms in two clinics, Children's Hospital West (CHW) and Children's Hospital East (CHE), demonstrates how physicians can influence institutional regimes of truth to improve patient access. Physicians at both clinics, far from simply acquiescing to dominant biomedical paradigms, recognize that their paradigms are in part rhetorical strategies designed to subvert problematic staff biases and perceptions, and to encourage a particular "self-efficacy" ethic in the patients. This paper positions physicians as struggling within the discursive regimes of biomedicine to create an institutional space where the disease and the sickle cell patient matter, and where patients comply with the performative rules of that space. This paper explores how physicians, patients, and institutions collaborate in the construction of sickle cell disease in such a way that biomedicine becomes a plural, as opposed to a singular and oppressive, discursive regime.  相似文献   
115.
Herrnstadt C  Howell N 《Mitochondrion》2004,4(5-6):791-798
More than 75 human diseases have been associated with mitochondrial dysfunction, and many of these are directly caused by overtly pathogenic mutations in the mitochondrial genome (mtDNA). In addition, there have been a number of reports that posit a different, subtler role for mtDNA substitutions in the disease process. As we review here, mtDNA evolution has resulted in the distribution of sequences into continent-specific haplogroups, which are defined by a relatively small number of polymorphisms. Thus, mtDNA sequences can be assigned to European, African, or Asian/Native American haplogroups. There are numerous reports that various diseases are haplogroup-associated, and it has been suggested that some of these haplogroup-associated polymorphisms act as risk factors in these disorders. It has also been suggested that there are haplogroup-associations for aging. As we note here, however, such associations have usually been observed only in single studies and it is difficult to draw broad conclusions on the basis of the available evidence. At a minimum, we suggest that, a haplogroup-group association must be detected in multiple subpopulations or in a large, carefully controlled population survey.  相似文献   
116.
传统中药白芍原植物分类鉴定及根形态解剖研究   总被引:3,自引:0,他引:3  
对我国主产地的白芍(Radix Paeonia alba)原植物10个居群进行调查及标本采集,植物鉴定结果为:川白芍原植物粉红花居群为原变种芍药Paeonia lactiflora Pall,白花居群为芍药变种毛果芍药P.lactiflora var.trichocarpa(Bunge)Stern;毫白芍原植物线条居群和蒲棒居群均为芍药;杭白芍原植物红花、白花、粉红花居群均为毛果芍药;陕西韩城、江苏东海、山东荷泽白芍均为芍药,各居群在花色及形态上有明显而稳定的变异。根横切面解剖结构显示,按木质部的排列方式可将白芍原植物10个居群分为两大类:第一类为有呈两个不相连的扇形中央导管群,并且有狭长、具分枝的从形成层到根中央部分连续排列的木质部,基本上是原植物芍药的植物特征,其中毫白芍线条居群兼有毛果芍药和芍药的特征;第二类为具有不明显的根中央扇形导管束,导管束呈环状围绕中央排列,并且有粗短不分枝的靠近形成层处成群的导管,与原植物毛果芍药的特征基本一致,其中杭白芍红花居群与川白芍白花居群根中央导管群呈现较明显的2个分离扇形排列,类似芍药。白芍原植物的种分类定位与花色无密切关联,但由于性状的稳定,可以考虑作为变种或变型定位。  相似文献   
117.
Summary St. John's wort (Hypericum perforatum L.) is a medicinal plant used in the treatment of neurological disorders and has been recently shown to have anticancer potential. The principle medicinal components of St. John's wort are hypericin. pseudohypericin, and hyperforin. One of the problems associated with medicinal plant preparations including St. John's wort is the extreme variability in the phytochemical content, mostly due to environmental variability, and biotic and abiotic contamination during cropping. The current study was undertaken to transplant St. John's wort plants from in vitro bioreactors in a closed controlled environment system (CCES) with CO2 enrichment for the optimized production of biomas and phytochemicals. The growth and levels of hypericin, pseudohypericin, and hyperforin in plants grown in CCES were compared with those of the greenhouse and in vitro-grown plants. The environmental parameters in the greenhouse were found to be variable whereas in the CCES these parameters were controlled. Generally, all the growth parameters and hypericin and psendohypericin levels were significantly higher in the plants grown in the CCES. These results provide the first indication that growing St. John's wort plants, under CO2 enrichment in a closed environment system can enhance the biomass and medicinal contents. The adaptation of this growing system may be useful for the production of optimized products of St. John's wort and other medicinal species.  相似文献   
118.
The aim of this article is to briefly present the Galler Collection, a little-known historic Swiss bone reference series of high value for paleopathological research. The Galler Collection consists of approximately 600 mostly dry-bone specimens of many major bone diseases dating from the late 19th and early 20th centuries. Clinical information and autopsy reports are available for the majority of specimens. Rarely documented conditions represented in the collection include: severe forms of myositis ossificans progressiva, kyphoscoliosis, endemic cretinism, hypo- and hyperparathyroidism, and phosphorus-induced bone necrosis. At present, the Galler Collection is located at the National History Museum in Basel (Augustinergasse 2, 4001 Basel, Switzerland, Telephone: +41612665500, Fax: +41612665546).  相似文献   
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120.
This paper examines the critical attitude of behavioral professionals toward spiritual phenomena, and the current growing openness toward a scientific study of spirituality and its effects on health. Health care professionals work amidst sickness and suffering, and become immersed in the struggles of suffering persons for meaning and spiritual direction. Biofeedback and neurofeedback training can facilitate relaxation, mental stillness, and the emergence of spiritual experiences. A growing body of empirical studies documents largely positive effects of religious involvement on health. The effects of religion and spirituality on health are diverse, ranging from such tangible and easily understood phenomena as a reduction of health-risk behaviors in church-goers, to more elusive phenomena such as the distant effects of prayer on health and physiology. Psychophysiological methods may prove useful in identifying specific physiological mechanisms mediating such effects. Spirituality is also a dimension in much of complementary and alternative medicine (CAM), and the CAM arena may offer a window of opportunity for biofeedback practice.  相似文献   
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