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An improved method is described for preparing the enzyme which hydrolyzes the polysaccharide acid contained in vitreous humor, umbilical cord, synovial fluid, and the mucoid phase of group A hemolytic streptococci. Preparations have been obtained from pneumococci, group A hemolytic streptococci, Clostridium welchii, and from splenic tissue, which display the same specific activity. Evidence is presented to show that the hydrolytic enzyme is not the same as that responsible for the lysis of pneumococci. In pneumococci and hemolytic streptococci the major portion of the enzyme is bound to the cell structure. The enzyme from Clostridium welchii is associated with other carbohydrate-splitting enzymes in the culture medium and not with the bacterial cells. It is suggested that the disappearance of the mucoid capsule of group A hemolytic streptococci is due to enzymatic hydrolysis of the acid polysaccharide. The relation between enzyme activity and the virulence and invasiveness of group A hemolytic streptococci is briefly considered.  相似文献   
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Latin American countries view biosimilar agents as an effective approach to curtail health‐care expenditures while maintaining the safety and efficacy profile of their branded innovator comparators. To understand the complexities of the regulatory landscape and key therapeutic issues for use of biosimilars to treat moderate to severe psoriasis in Latin America, the International Psoriasis Council convened dermatology experts from Argentina, Brazil, Chile, Colombia and Mexico in October 2015 to review the definition, approval, marketing and future of biosimilars in each country and develop a consensus statement. The regulatory framework for marketing approval of biosimilars in Latin America is currently a mosaic of disparate, country‐specific, regulatory review processes, rules and standards, with considerable heterogeneity in clarity and specificity. Regulations in Argentina, Brazil, Chile and Mexico have undergone multiple refinements whereas Colombia is finalizing draft guidelines. Verification of the similarity in quality, safety and efficacy of biosimilars to the innovator biologic remains a key challenge for policy makers and regulatory authorities. Other key regulatory challenges include: naming of agents and traceability, pharmacovigilance, extrapolation of indications, and interchangeability and substitution. An urgent need exists for more Latin American countries to establish national psoriasis registries and to integrate their common components into a multinational psoriasis network, thereby enhancing their interpretative power and impact. A Latin American psoriasis network similar to PSONET in Europe would assist health‐care providers, pharmaceutical companies, regulators and patients to fully comprehend specific products being prescribed and dispensed and to identify potential regional trends or differences in safety or outcomes.  相似文献   
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Objectives: Mini-implants are used for orthodontic bone anchorage. The reasons for a potential instability or loss of the mini-implants during treatment are multiple. Among other factors, colonization of implants with pathogenic bacteria is discussed. Therefore, the microflora associated with successful and failed mini-implants has been screened.
Material and methods: A total of 76 mini-implants collected from 25 patients were observed during regular orthodontic treatment. Bacterial samples of eight failed and – exemplarily – four successful (control) cases were subjected to a universal Bacteria -directed real-time quantitative polymerase chain reaction for quantification in combination with a microarray-based identification of 20 selected species.
Results: The failure rate in the present investigation was 10.5%. The bacterial analysis did not reveal any major difference in the total amount or species composition between control and failed mini-implants. However, Actinomyces viscosus was found in four (100%) and Campylobacter gracilis in three (75%) stable controls, whereas both species were rarely found (12.5%) in failed implants.
Conclusions: In the present study, the peri-implant sulcus surrounding failed orthodontic mini-implants did not show a specific aggressive bacterial flora.  相似文献   
55.
An easy and rapid second-derivative spectrophotometric method for the simultaneous analysis of trimethoprime (TMP) and sulfamethoxazole (SM) is described. These drugs have been used as antibacterial against a wide spectrum of organisms and combinations of these drugs are commonly used for the treatment of a variety of infections. The most advantageous approach of this method is the use of HP-beta-CD, which allows to improve the performance of the second-derivative ultraviolet spectrophotometry. For both compounds, a shift of the absorption bands and variations of their intensity were observed. The calibration graphs were linear in the concentration range of TMP (1.92-19.2 microg ml(-1)) and SM (1.60-16.5 microg ml(-1)), the correlation coefficient for the calibration graphs was better than 0.9994 and the precision was satisfactory (CV%< 4.96) in HP-beta-CD solutions. The proposed method was successfully applied to the assay of commercial tablets. The results were compared to those obtained by second-derivative ultraviolet spectrophotometry in the absence of HP-beta-CD. Thereby, the details of the statistical treatment of the analytical data are also presented.  相似文献   
56.
BACKGROUND: Over at least the past ten years, measures aimed at health promotion and prevention among young adults and teenagers have been being implemented from different public institutions and, in a certain sense, on a sectorial basis. The overall objective is to assess how the different measures carried out by different Public Institutions with regard to Health Promotion and Prevention have an impact on the actual conduct and practices of teenagers and young adults within the 14-25 age range in the Autonomous Community of Madrid. METHODS: A study based on a structural or qualitative methodology was conducted using the discussion group method, eight groups having been formed and their comments analyzed. RESULTS: The young adults do not feel any health-related prevention "system" as such exists on not considering themselves to be the object thereof. In the opinion of the young adults, disease, confined to the physical body, is conceived as being a short-lived, temporary and readily remedied based on the technological advances current medicine has to offer. On the contrary, the diseases related to the psychological perspective (mental disease dissociated with the area of the medical and connected to the individual/personal area) arouse interest in so much as young people are highly vulnerable to these diseases. CONCLUSIONS: Any measure aimed at generating identification and, therefore, the active response of young people must entail creating a connection between young people and health, which, not based exclusively in providing information, is capable of putting a space of control of the youths with regard to their harmful practices into play whilst at the same time highlighting their taking responsibility for their own actions. Considering we believe it best to "redefine" the term "prevention" in terms nearer to those of maintaining, improving or regaining (in short-lived cases) health, to thus connote the idea of physical and mental well-being.  相似文献   
57.
The effects of acamprosate, a drug thought to interact with N-methyl-D-aspartate (NMDA) receptors in the central nervous system (CNS), were examined on the antinociceptive action of morphine, induction of tolerance to and physical dependence on morphine, and expression of the abstinence syndrome to the opiate in mice. For the induction of tolerance and dependence, morphine (300 mg/kg) was administered by means of a slow-release preparation. Single doses of acamprosate (50, 100, 200, or 400 mg/kg) administered 30 min before a test dose of morphine did not change the antinociceptive effects of morphine in drug-naive mice. The drug was also administered in repeated doses (50, 100, 200, or 400 mg/kg, 30 min before and 12 and 24 h after the priming dose of morphine) in order to evaluate its effects on the induction of tolerance; all doses assayed, except the 400 mg/kg, did not affect the intensity of tolerance. The acute administration of acamprosate (50, 100, 200, or 400 mg/kg, injected 30 min before naloxone to morphine-pretreated mice) did not affect the intensity of the abstinence behavior. However, the repeated administration of 100 mg/kg of acamprosate (30 min before and 12 and 24 h after the priming dose of morphine) decreased the intensity of physical dependence. The results of these studies suggest that acamprosate may have modulatory effects on glutamatergic neurotransmission participating in the adaptive mechanisms induced by chronic morphine treatment.  相似文献   
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BACKGROUND: Adequate intakes of calcium and vitamin D reduce bone loss and fracture risk in the elderly. Other nutrients also affect bone health, and adequate intakes may influence bone turnover and balance. OBJECTIVE: We compared the long-term effects on bone turnover markers and calciotropic hormones of a multinutrient supplement, a calcium and vitamin D supplement, and dietary instruction aimed at increasing calcium intake through foods. DESIGN: Ninety-nine healthy postmenopausal women participated in a 3-y, randomized trial, receiving either 1) supplemental calcium (1450 mg/d) and vitamin D [10 microg (400 IU)/d], 2) calcium, vitamin D, and other nutrients (multinutrient supplement), or 3) dietary instruction (dietary control group). Data are from 83 subjects who completed the trial. RESULTS: Increases over baseline in calcium intakes and serum 25-hydroxyvitamin D concentrations were sustained over 3 y in all treatment groups. Circulating parathyroid hormone concentrations were reduced at year 1 in all treatment groups but trended toward baseline thereafter. Bone turnover markers followed a similar pattern, and none of the changes in biochemical concentrations differed significantly between groups. CONCLUSIONS: All 3 interventions offer long-term feasibility for increasing calcium intake and serum 25-hydroxyvitamin D concentrations. The dietary addition of micronutrients implicated in skeletal physiology confers no obvious bone-sparing effect in healthy postmenopausal women beyond that of calcium and vitamin D alone. The attenuation over time in suppression of parathyroid hormone and bone turnover might help explain why nutrient intervention tends to have less of a bone-sparing effect than do skeletally active medications such as estrogen or bisphosphonates.  相似文献   
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