What Is Internal Resorption?
Internal absorption often refers to internal absorption of teeth and internal absorption of plant elements.
- Internal absorption often refers to internal absorption of teeth and internal absorption of plant elements.
- Dental absorption can be divided into physiological absorption and pathological absorption. For example, the root absorption of mature deciduous teeth is a physiological process. Pathological dental absorption includes extradental and intradental absorption. The occurrence of extradental absorption is usually related to periapical lesions, orthodontic treatment and fast-growing tumors. The starting site is the outer surface of the root or the neck of the tooth. Intradental absorption is also known as intramedullary cavity absorption, which refers to the normal granulation degeneration of dental pulp tissue, causing the hard tissue inside the pulp cavity to absorb and gradually progress to the surrounding dentin layer. Failure to get timely treatment may lead to premature loss of diseased permanent teeth. Permanent tooth absorption is relatively rare, and often without obvious clinical symptoms, most cases were found during routine imaging examination. However, there are no obvious imaging changes in the early stage of the lesion, which makes the early diagnosis of intra-dental absorption more difficult. Therefore, when symptoms of the affected teeth or imaging changes occur, the lesions have often progressed to a more severe stage, making the treatment more difficult and the long-term effect is not good. [1]
- Systemic absorption is an important component of plant nutrition protection strategies. Plant leaves are rich in available elements, so systemic absorption during leaf senescence
- There is a lot of evidence that primary productivity is limited by nitrogen in salt marsh ecosystems. This is caused by many factors: on the one hand, nitrogen-fixing bacteria are less active in the soil of mangroves under anoxic conditions, and the soil A large amount of N element is released into the air due to factors such as denitrification and cannot be used by plants. On the other hand, true mangrove plants are considered to have a higher leaf fall rate than evergreen plants. This is an important adaptation of mangrove plants to high-salt environments, but it is small and unavoidable to make N, P and other elements in the leaves Lost from the plant with fallen leaves. Although this part of the nutrient can be re-entered into the nutrient cycle through the decomposition of mangrove soil microorganisms, the seawater still takes away a large part of the machine litter. Therefore, the average annual nitrogen input of mangrove ecosystems is less than the nitrogen output. Although there is still some controversy, the restricted nutrient elements of mangroves may vary depending on factors such as location, but in fact, in most red mangroves In forests, soil nitrogen supply is usually small enough to meet plant nitrogen requirements, and internal uptake is of particular significance. In the experimental results of this study, the leaf N / P of both true and semi-mangroves was less than 31. According to the evaluation criteria of Gusewell and Koerselman, the mangroves in our experimental plots are N-limited. [3]
- Nutrient contents (Nmass and Pmass) in mature leaves were considered to be related to soil element supply levels. There is no doubt that if grown in more fertile soil, plants can get more nutrients and the leaf nutrient content will be higher. Generally, in poor environments, the nutrient content of leaves will increase with the increase of soil nutrients. According to Lin and Sternberg, the nutrient content of mangrove plant tissue is the result of long-term adaptation to the environment. In this study, mature leaves of semi-mangrove plants have higher nutrient content (Amass and Pmass) than true mangrove plants. A phenomenon confirms our hypothesis that semi-mangrove plants have a better soil nutrient supply (N and P) environment than true mangrove plants. [4]