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991.
The ability to sustain attention over time (vigilance) is a cognitive function that often is impaired in patients with psychiatric disorders. Attention has been found to be disordered in a number of psychiatric conditions, including attention deficit disorder, schizophrenia, antisocial personality disorder, and the impulse control disorders. Less widely known is the finding that attention also is affected in patients suffering from anxiety disorders, posttraumatic stress disorder, mood disorders, and borderline personality disorder.In this article, the significance of attention deficits with regard to the mood disorders, anxiety disorders, posttraumatic stress disorder, and borderline personality disorder, is described.  相似文献   
992.
Abstract – Background: Dental injuries occur commonly in childhood and may necessitate demanding courses of treatment. The aim of this study was to investigate a variety of clinical and demographic factors that may influence the quality of life impacts experienced by children after a dental injury. Method: A total of 244 children who attended a UK dental hospital, for management of traumatised permanent incisors, were invited to participate in the study. Clinical, demographic and psychosocial variables were collected at baseline, and outcome variables were assessed again at a 6‐month follow up. Clinical variables included number of teeth injured; severity of the dental injury; visibility of the injury; time since injury; and number of dental appointments attended within the hospital. Psychosocial outcomes assessed included children’s oral health‐related quality of life (OHRQoL) and health‐related quality of life (HRQoL). Results: One hundred and eight children participated in the baseline study (44% response rate), and of this group of children, a total of 70 children completed follow‐up questionnaires (65% response rate). The results indicated that the most affected areas of children’s OHRQoL and HRQoL were functional limitations and school‐related activities, respectively. Of all the demographic and clinical variables, which were investigated within the current study, the only variable that significantly predicted OHRQoL and HRQoL for children was gender. Boys were found to report fewer impacts on their OHRQoL and HRQoL than girls. Interestingly, over two‐thirds of children reported fewer impacts at the 6‐month follow up. Conclusions: The results revealed that girls were more likely to report higher level of impacts on their OHRQoL and HRQoL than boys following traumatic injury to their permanent incisors. Clinical variables were not significant predictors of child quality of life outcomes following dento‐alveolar trauma at baseline or at the 6‐month follow up.  相似文献   
993.
Clinical manifestations of severe periodontitis are very often associated with tooth migration. The aim of this retrospective study is to evaluate dental bone support before orthodontic-periodontal treatment, at immediate postoperative, and long-term postoperative and to compare these results with those obtained from periodontal treatment alone. Fifteen patients (11 women and four men), all with severe periodontitis, mean age 42.8 years (22–61), were followed for an average of 16 years (11–32). Comparison was made between periodontal–orthodontic treatment (Group 1) and periodontal treatment alone (Group 2). Alveolar bone height was measured at T0 (before treatment), T1 (immediate postoperative) and T2 (long-term postoperative). Assessment was performed by means of digitized radiography using Image J Software from the National Institute of Health. The average postoperative observation period between T0 (before treatment) and T2 (long-term results) was 16 years (11 to 32). Results showed an overall bone apposition in groups (1 and 2) immediately after treatment (T1), then at long-term (T2). No statistical difference was observed between both groups (1 and 2). In conclusion: an overall bone gain was observed in both treatment groups (periodontal–orthodontic and periodontal alone). The orthodontic treatment combined with periodontal treatment never compromised the benefits of periodontal treatment alone. On the opposite, it appeared to be quite beneficial.  相似文献   
994.
This is a case report of a female patient who demonstrated bilateral posterior crossbite with isolated cleft palate. Molar relation was Class I on the right side and Class II on the left side. Maxillary dental midline was deviated 1.0 mm to the left. To establish the Class I relation, comprehensive orthodontic treatment without extraction was planned. Initially, an open coil spring was activated between the first premolar and the first molar to make space for the second premolar. Subsequently, Class II elastics were used to align the dentition and establish Class I relation. Bilateral crossbite was significantly improved, and the molar relation improved to Class I. Although the maxillary arch width was slightly decreased post-retention, intercuspation was maintained during the retention phase.  相似文献   
995.
Quantitative study of apoptosis in normal rat gastroduodenal mucosa   总被引:1,自引:0,他引:1  
The occurrence of apoptosis in the normal gastrointestinal mucosa has been given little consideration until now, although the phenomenon may be of interest in the light of recent hypotheses about its role in physiological cell renewal. In the present study, a quantitative evaluation conducted on normal gastric and duodenal mucosa of young rats has shown that apoptosis is a rare but constant phenomenon: 1.4 +/- 1.1 (mean +/- 1 s.d.) apoptotic bodies were observed within the surface epithelium of single gastric pits and 3 +/- 1 in duodenal villi. In both situations, the apoptosis showed a preferential localization in the juxtaluminal segments of the epithelium. This phenomenon appears distinct from passive exfoliation of mucosal cells and, as an expression of 'programmed cell death', it is likely to contribute to the normal intestinal epithelial cell turnover.  相似文献   
996.
997.
Tachyzoites ofToxoplasma gondii have been shown to exocytose the contents of dense granules into the parasitophorous vacuole after host cell invasion. A monoclonal antibody specific for a 27-kDa protein was used to locate the dense granules by immunoelectron microscopy. The same antibody also reacted with the tubular network found in the parasitophorous vacuole, which confirmed that the dense granules were exocytosed by tachyzoites.  相似文献   
998.
Summary Aldosterone increases the basolateral conductance in target epithelia. The basolateral membrane of tight epithelia contains two different types of K+ conductances (GK), a resting and a volume-activated GK. We have studied the early effects (at 4 hours) of 500 nmol/l aldosterone on the basolateral membrane Gk of A6 cells (a Xenopus laevis kidney cell line), after the permeabilization of the apical membrane with amphotericin B. In the presence of a 97 to 3 mmol/l apical to basolateral K+ gradient, the resting, inward rectifying GK was similar in control and aldosterone treated cells. In contrast, aldosterone induced a 2-fold increase of the volume-activated quinidine sensitive GK.  相似文献   
999.
Advanced glycation end products (AGEs), the final products of nonenzymatic glycation and oxidation of proteins, are found in the plasma and accumulate in the tissues during aging and at an accelerated rate in diabetes. A novel integral membrane protein, termed receptor for AGE (RAGE), forms a central part of the cell surface binding site for AGEs. Using monospecific, polyclonal antibody raised to human recombinant and bovine RAGE, immunostaining of bovine tissues showed RAGE in the vasculature, endothelium, and smooth muscle cells and in mononuclear cells in the tissues. Consistent with these data, RAGE antigen and mRNA were identified in cultured bovine endothelium, vascular smooth muscle, and monocyte-derived macrophages. RAGE antigen was also visualized in bovine cardiac myocytes as well as in cultures of neonatal rat cardiac myocytes and in neural tissue where motor neurons, peripheral nerves, and a population of cortical neurons were positive. In situ hybridization confirmed the presence of RAGE mRNA in the tissues, and studies with rat PC12 pheochromocytes indicated that they provide a neuronal-related cell culture model for examining RAGE expression. Pathological studies of human atherosclerotic plaques showed infiltration of RAGE-expressing cells in the expanded intima. These results indicate that RAGE is present in multiple tissues and suggest the potential relevance of AGE-RAGE interactions for modulating properties of the vasculature as well as neural and cardiac function, prominent areas of involvement in diabetes and in the normal aging process.  相似文献   
1000.
The prophylactic and therapeutic effects of gold sodium thiomalate, cyclosporin A, cyclophosphamide, and placebo on collagen-induced arthritis (CIA) were evaluated in DA rats. Prophylactic treatment with cyclosporin A and cyclophosphamide suppressed the arthritis incidence, clinical inflammation, destructive bone changes, and development of anti-collagen antibody in DA rats subsequently injected with porcine type-II collagen. Therapeutic treatment with cyclosporin A and cyclophosphamide had a definite suppression on established CIA when started 21 days after the initial collagen injection, but the suppression was less marked than that of prophylactic treatment. Gold had no impact on CIA in DA rats when administered either prophylactically or therapeutically.  相似文献   
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