Calcium phosphate ceramics, such as tricalcium phosphate (TCP) and hydroxyapatite (HA) are commonly used as bone substitutes. These materials have different physical and chemical properties and, therefore, display different interactions with the host tissue. Factors such as porosity,osteoconductivity,and biocompatibility seem to become increasingly important in the development of new artificial bone replacement materials. This article focuses on the relationship between the physical and chemical properties of calcium phosphate ceramics and the host tissue.

BACKGROUND: Drug-controlled release preparation by drugs or other active substances combined with carriers, has been an important development trend in field of pharmacy. However different characteristics of controlled release drug carrier materials leas to different drug release behaviors, so recent researches focus on a new type of drug carrier material to obtain the satisfactory drug release. OBJECTIVE: To introduce some drug carrier materials, and analyze those materials' characteristics and their application on drug controlled-release. RETRIEVAL STRATEGY: A computer-based search was undertaken on China Journal Full-text Database from January 1998 to June 2007, with the Keywords of "polymeric hydrogel, polylactic acid, chitosan, silk fibroin, drug controlled-release, drug carrier" and language was limited to Chinese. Inclusion criteria: ①preparations and characteristics of various drug carrier materials;②drug controlled release of various drug carrier materials. Exclusion criteria: outdated literatures. LITERATURE EVALUATION: Eighty-six related articles were screened out, and 28 of them met the criteria, including 10 were reviews and others were clinical or basic experiments. DATA SYNTHESIS: ① At present, the materials applied for drug carrier include polymeric hydrogel, polylactic acid/poly(lactic-co-glycolic acid), chitosan and their derivates, silk fibroin and so on.②Intellectual polymeric hydrogel can respond swelling and contraction for the stimulation of temperature, acidity, pressure and light, etc. And the specific environment sensitiveness enlarges its application in drug delivery system.③Polylactic acid and poly(lactic-co-glycolic acid), as a kind of biodegradable polymer materials, represent biocompatibility, biodegradability and non-toxic degradation products. As for controlled release drug carrier material, it can influence drug release by modulating degradation of polylactic acid, so as to increase drug efficacy.④Chitosan is satisfactory in adsorbability, film forming ability and permeability. Water-soluble chitosan with low relative molecular mass is prone to degrade and difficult to accumulate, so chitosan nanoparticles or chitosan microspheres as carriers for drug delivery system have been the hot topic of recent researches.⑤Native polymer material silk fibroin is non-toxic and non-stimulative, shows good physical, chemical and biological characteristics, as well as satisfactory histocompatibility. The pH value responsibility and zymohydrolysis are also observed when loading and releasing drugs. Chemical modification and addition of other compounds will increase the characteristics and the drug-controlled release of silk fibroin. CONCLUSION: Various drug carrier materials show good biocompatibility, biodegradability, physicochemical and biological stability, extremely low toxicity, and high drug loading property. But the material's performance should be synthesized and modified in practical application to satisfy various preparations of drug-controlled release by specific performance and structure.

Polypeptide and protein microspheres can elevate drug availability, but drug devitalization and drug fast release can result in side effects during microsphere preparation. Fast release in the body is a burning question facting investigators who studying microsphere controlled release system. Relative molecular mass, concentration, structure and drug content of the polyme can greatly affect drug fast release. Fast release can be controlled by structural modification, using additives, controlling particl diameter of microspheres and decreasing drug content.

Objective: To study the impact of basic medical insurance on household consumption. Methods: According to the panel data of the east, central and west regions from 2002 to 2011, time and entity fixed effect model (Two-way FE) is established to test the relationship between the basic medical insurance and household consumption. Results: The basic medical insurance has significant positive effects on consumption, the consumption increased 10%, 16% and 19% in regions of East, Middle and West, respectively. Conclusion: The construction and improvement of the social medical insurance system improve the growth of the consumption, and the government should enhance the security, and consider the regional differences at the same time.

Breast Feeding ; Enteral Nutrition ; Epigenesis, Genetic ; Humans ; Infant ; Infant Formula ; Infant Nutritional Physiological Phenomena ; Infant, Low Birth Weight ; growth & development ; Infant, Newborn ; Infant, Premature ; growth & development ; Infant, Premature, Diseases ; prevention & control ; Nutrition Assessment ; Nutritional Status

Guidelines as Topic ; Humans ; Infant, Low Birth Weight ; Infant, Newborn ; Infant, Premature ; Nutritional Physiological Phenomena

BACKGROUND: Local application of sustained-release antimicrobials serve as an adjuvant therapy of periodontitis, and the dosage form, medicine and carrier material have greatly developed. OBJECTIVE: To summarize the currant situation and progression of periodontal local sustained-release antimicrobials at home and abroad.METHODS: A computer-based online search of CNKI and Pubmed (1999-01/2009-10) was performed for the related articles about sustained-ralease antimicrobials, with the key words "periodontitis, treatment, medication, and sustained-ralease". The articles in the same field published recently or in authoritative journals were selected. A total of 143 articles were collected, and 40 related sustained-ralease antimicrobials were included.RESULTS AND CONCLUSION: Application of sustained-release antimicrobials is a well adjuvant therapy for some special clinical periodontitis. It is widely used due to its low dosage, long lasting-time and well target effect. The clinical application of sustained-ralease antimicrobials is promising along with the development of compound medicine and periodontal tissue regeneration.

Multi-drug resistance (MDR) of breast cancer is a key factor of breast cancer treatment failure.MicroRNA (miRNA) is a class of endogenous expressed,small,single-stranded RNA molecules,and regulate the expression of genes at post-transcriptional level by combining with target message RNA.MiRNA participate in the mechanisms of drug resistance of breast cancer,and are feasible therapeutic targets for the treatment of drug resistance in breast cancer.Finding and studying miRNA related with drug resistance of breast cancer as well as their mechanisms have become a current research hotspot.

Smoking remains a main cause of preventable death worldwide.The World Health Organization strategizes the implementation of tobacco control through primary care services.A community-based primary care (COPC) service fully considering social,environmental and life style influence on health,combines individual medical service and population based intervention.COPC guided smoking cessation intervention program is introduced with safety,convenience and cost-effectiveness,and it is an important approach to promote bealth among smoking population.

Objective To evaluate the changes in the expression of neuron-restrictive silencer factor (NRSF) in the spinal cord of mice with bone cancer pain.Methods Forty-eight pathogen-free adult male C3H/HeJ mice,aged 4-6 weeks,weighing 20-25 g,were randomly divided into 2 groups (n=24 each) using a random number table:sham operation group (group S) and bone cancer pain group (group BCP).Bone cancer pain was induced by injecting 2× 105 NCTC2472 osteolytic sarcoma cells in α minimal essential medium into the medullary cavity of the right distal femur in group BCP.Only α minimal essential medium was injected into the medullary cavity of the right distal femur in group S.The mechanical and thermal pain thresholds were measured on 5,7,10 and 14 days after inoculation (T1-4).Six mice in each group were randomly selected after measurement of pain thresholds at T1-4 and sacrificed,and the lumbar enlargement segments of the spinal cord were harvested to detect the expression of NRSF.Results Compared with group S,the mechanical pain threshold at T2-4 and thermal pain threshold at T3.4 were significantly decreased,and the expression of NRSF was significantly down-regulated at T1-4 in group BCP (P＜0.05).Conclusion The mechanism underlying the development of bone cancer pain is probably related to down-regulation of NRSF expression in the spinal cord of mice.