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Cytokines as therapeutic drugs.   总被引:1,自引:0,他引:1  
Cytokines are a growing group of proteins that are responsible for the communication of cells of the immune system, hematopoietic cells, and other cell types. They play a dominant role in various diseases, particularly in promoting and perpetuating inflammation. Cytokine production is a reaction of the body to a pathologic state to restore homeostasis. In such cases, the therapeutic intervention should support the reaction of the body by giving the cytokine itself (agonistic therapeutics). In other cases, manifestation of a disease results from an overproduction of cytokines, making cytokine antagonists desirable therapeutic drugs. Furthermore, cytokines may be good candidates as cancer therapeutics, especially to support the restoration of blood cell populations after chemotherapy or radiation.  相似文献   
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The purpose of this study was to provide, in a large number of patients, comprehensive Doppler echocardiographic assessment of normal St Jude Medical mitral valve prosthesis function using Doppler-derived hemodynamic variables, including the mitral valve prosthesis-to-left ventricular outflow tract time-velocity integral ratio and prosthesis performance index. The pressure half-time was less than 130 milliseconds in all patients, and all but one patient had either a peak early mitral diastolic velocity of 2 m/s or less or a mitral valve prosthesis-to-left ventricular outflow tract time-velocity integral ratio of less than 2.2. There was a significant (P < .001) negative correlation between the prosthesis performance index and prosthesis size. This negative correlation suggests that there is more efficient use of the in vitro geometric orifice area with smaller prostheses.  相似文献   
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INTRODUCTION: Incisor trauma is a significant clinical problem in children and adolescents. The purposes of this study were to report on the prevalence and severity of incisor trauma in a large population-based sample of adolescent Kuwaiti residents in the early permanent dentition, to determine the ages of and reasons for the injuries, and to test for any effects of sex, incisor occlusion, and lip coverage on the prevalence of incisor trauma. METHODS: Presence and type of traumatic injury were scored according to the National Institute of Dental Research index in a population-based sample of 795 girls and 788 boys with a mean age of 13.24 years (SD 0.42). RESULTS: Trauma prevalence was higher (P < .001) in boys (19.3%) than in girls (9.7%), and in the maxilla (13.6%) than in the mandible (1.5%). Most (77.3 %) of the affected subjects had only 1 injured tooth, and most (83.7%) of the traumatized teeth were maxillary central incisors. A total of 90.3% of the injuries were unrepaired enamel or enamel/dentin fractures. The major reasons for the injuries were falls and blows indoors (48.4%) or outdoors (41.6%). Nearly two-thirds (63.0%) of the traumas occurred at age 10 years or later. Mean overjet (OJ) was larger (3.9 v 3.0 mm, P < .01), and lip incompetence more frequent (12.7% v 7.3%, P < .01) among the subjects with injured maxillary incisors than among those without. Logistic regression showed that the odds of maxillary incisor trauma were 2.8 times higher in subjects with OJ between 6.5 and 9.0 mm, and 3.7 times higher in subjects with OJ > or = 9.5 mm than in subjects with OJ < or = 3.5 mm. CONCLUSIONS: Multiple logistic regression showed that the risk of maxillary incisor trauma was about 2 times higher in boys than in girls, and that the risk increased by 13% for every millimeter of increase in OJ. Lip competence was not included in the model. No associations were found between occlusion and mandibular incisor trauma.  相似文献   
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The induction of a granulomatous inflammation by jellyfish toxins is rare. More typically, acute toxic and urticarial reactions are seen. An 11-year-old boy developed a striated urticarial erythema on the left cheek after contact with a gelatinous mass while swimming in the sea in Croatia. After initial erosion, a striated induration developed in the area of contact. Histological examination revealed a granulomatous inflammation with some eosinophils. While topical steroid-based antiinflammatory and antibacterial therapy over several weeks was not effective, topical therapy with tacrolimus 0.1% for two two-week treatment periods led to healing of the skin changes with a slight scar. There was no clinical recurrence after 5 month of follow-up.  相似文献   
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BACKGROUND: The purpose of this study was to access a sample of short-bowel patients receiving home total parenteral nutrition (HTPN) in their home environment and describe their HTPN experience using qualitative methodology. METHODS: Three semistructured, open-ended, in-depth interviews were conducted online over a 5-month period with 6 adults (aged 27 to 45 years) who received HTPN for 2 to 8 years, 3 children (aged 8 to 10 years) receiving HTPN since birth, and the children's mothers. The constant comparison method was used to code and categorize data, inductively develop themes, and create a taxonomy (flow chart) of themes from the data. Credibility of data analysis and themes was established by the prolonged engagement with subjects and subject review of themes identified. RESULTS: Six major themes emerged: affirmation of life, infusion-related complications, lifestyle adaptations, self-worth, isolation, and food intake. Within most themes, subjects described similar concerns and reactions. A clear difference occurred within the theme of food intake. Adults reported feeling constantly hungry and challenged with resisting temptation to eat restricted foods. They admitted to lack of consistency in following dietary restrictions and repeated attempts to consume contraindicated foods. Children expressed lack of desire for food and mothers complained of their children's refusal to eat. CONCLUSIONS: Using qualitative methods allowed insight into the HTPN experience and depiction of the daily challenges of being total parenteral nutrition-dependent from patients' and caregivers' perspectives. It provides insight into their reactions and behaviors. By gaining this type of awareness and understanding, clinical protocols and services can be planned that are more likely to derive successful outcomes.  相似文献   
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Background  

The behaviour of children with Attention-Deficit/Hyperactivity Disorder is characterized by low predictability of responding. Low behavioural predictability is one way of operationalizing intra-individual ADHD-related variability. ADHD-related variability may be caused by inefficient behavioural selection mechanisms linked to reinforcement and extinction, as suggested by the recently published dynamic developmental theory (DDT) of ADHD. DDT argues that ADHD is a basic neurobehavioural disorder, caused by dysfunctioning dopamine systems. For establishing ADHD as a neurobehavioural disorder, findings from studies conducted in Western countries should be replicated in other cultural populations. The present study replicated the study conducted in Norway, with children from the Limpopo province in the Republic of South Africa.  相似文献   
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The objective of this study was to determine if non-psychiatric morbidity increases with age in a group of low-income psychiatric outpatients. Data on demographics, presenting complaints, DSM-III diagnoses and use of psychiatric services were collected on all individuals (N = 382) admitted to a psychiatric outpatient clinic serving low-income population. Non-psychiatric morbidity was identified on the basis of medical history, physical examination, and laboratory investigations. Bivariate analyses were done to determine the significance of the associations of comorbidity with other variables. A logistic regression was done using the presence or absence of comorbidity as the dependent variable. Age was the only variable which was significantly predictive of comorbidity. Additional resources should be allocated for the diagnosis and treatment of comorbidity among low-income elderly.  相似文献   
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