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931.
The global health scenario shows an epidemic of non‐communicable diseases that lead to long‐term chronic conditions, some of which are incurable. Many infectious diseases, owing to their development and length, also generate chronic conditions. Similarly, non‐morbid states, such as pregnancy, and some life cycles such as adolescence and ageing, follow the same logic. Among all these chronic conditions there is a significant interrelationship with oral health, both in parallel events and common risk factors. This article presents cross‐sectional qualitative research into World Health Organisation recommended health policies to address chronic conditions. Several documents published by the organisation were analysed to verify the presence of references to oral health in relation to chronic conditions, particularly cardiovascular diseases and diabetes as these most frequently have oral manifestations. The analysis showed no significant references to oral health or its indicators within the published texts. The study recognises the value of the work developed by the World Health Organisation, as well as its worldwide leadership role in the development of health policies for chronic conditions. This article proposes a coalition of dentistry organisations that could, in a more forceful and collective way, advocate for a greater presence of oral health in drafting policies addressing chronic conditions.  相似文献   
932.
Background: Clinical evidence suggests an association between preterm birth and periodontal disease. This study explores whether specific genetic polymorphisms are associated with success of periodontal therapy in pregnant women with periodontal disease and, further, whether any of these same polymorphisms are also associated with spontaneous preterm birth (sPTB). Methods: One hundred sixty high‐risk pregnant women (6 to 20 weeks of gestation) with periodontal disease (≥3 sites with attachment loss ≥4 mm) were studied. All women received scaling and root planing plus oral hygiene instruction. Periodontal examinations were performed before treatment and 20 weeks later. Participants were classified according to two study outcomes: 1) success or failure of periodontal treatment; and 2) presence or absence of sPTB. Maternal DNA samples from mucosal swabs were characterized using a 1536‐SNP (single‐nucleotide polymorphism) custom polymerase chain reaction chip. A probabilistic model of each dichotomous outcome, derived using a stepwise Bayesian procedure, was compared to respective null hypotheses on the basis of Monte Carlo simulations and significance estimates obtained using three measures (z‐test, Welch t‐test, and probability convolution). The models were further confirmed by logistic regression analyses. Results: The models revealed a significant relation between a specific polymorphism of prostaglandin E receptor 3 (a gene associated with inflammatory response) and both periodontal treatment failure (odds ratio 11.09, P <0.0002) and sPTB (odds ratio 6.89, P <0.0032). Conclusions: These results demonstrate that the risk of unsuccessful periodontal treatment is associated with tag SNPs in specific genes that regulate the inflammatory response, one of which is also associated with sPTB.  相似文献   
933.
The aim of this review was to examine current knowledge of the role of interleukin‐6 (IL‐6) in apical periodontitis (AP) pathogenesis as an inflammatory or pro‐inflammatory cytokine. It also looked at whether IL‐6 could serve as a measure for differential diagnosis or as a biomarker that can further predict the progression of bone resorption. A systematic review relating to AP and IL‐6 was made via PubMed, BIOSIS, Cochrane, EMBASE and Web of Science databases using keywords and controlled vocabulary. Two independent reviewers first screened titles and abstracts and then the full texts. The reference lists of the identified publications were examined for additional titles. Eighteen papers were studied in total. In vitro studies (= 6) revealed that IL‐6 is present in AP, and its levels are proportional to the size of the periapical lesions. Neutrophils and macrophages resident in these lesions can produce IL‐6 in vitro after a bacterial stimulus. Animal studies (= 5) showed that IL‐6 is present in AP and that osteoblasts can produce IL‐6 in vivo. On the other hand, two studies using IL‐6 knockout mice revealed larger periapical lesions when compared with control groups, demonstrating IL‐6's role as an anti‐inflammatory cytokine. In human studies (= 7), IL‐6 was identified in AP, and its levels were higher in symptomatic, epithelialized and large lesions than in asymptomatic and small lesions. These data lead to the conclusion that IL‐6 may play a pro‐inflammatory role, increasing its levels and reabsorbing bone in the presence of infections. When IL‐6 is not present, other cytokines such as IL‐1 and TNF‐α induce bone resorption. Further studies about the relationship between AP development and the cytokine network must be performed to establish the exact role of each cytokine in the inflammatory process.  相似文献   
934.

Background

Measles is a highly contagious vaccine-preventable infection which continues to be a significant cause of childhood morbidity and mortality in developing countries particularly those with poor routine immunisation coverage. Supplemental immunisation activities (SIAs) were thus introduced to improve vaccine coverage.

Objective

This study was carried out to assess the impact of the supplemental measles vaccinations on the cases of measles admitted at a tertiary health facility in South west Nigeria.

Methods

Weretrospectivelylooked at therecords of cases of measles in children admitted to the Wesley Guild Hospital, Ilesa over a ten year period (2001 – 2010); five years before and five years after the nationwide commencement of supplemental measles immunisation activities (SIAs) in the region in 2006. Measles cases were defined using the WHO case definition.

Results

Over the ten year study period, a total of 12,139 children were admitted andmanaged; out of which 302 (2.5%) were cases of complicated measles. There was no difference in the mean (SD) of children admitted in the years before and after the introduction of the SIAs {6040 (122.7) vs.6099 (120.2); t-test 0.02, p =0.988.} There was however a remarkable reduction in the proportion of the cases of measles admitted after the introduction of SIAs compared to the period before SIAs (4.3% vs. 0.6% x2=169.580; p < 0.001)

Conclusion

SIAs have remarkably reduced morbidity and mortality associated with measles in the region. We advocate for sustenance of these efforts as well as improvement in routine immunisation coverage to avoid a backlash which can lead to devastating measles outbreak.  相似文献   
935.
Epidermoid cysts are benign subcutaneous lesions, and the large majority of these cysts affect the floor of the mouth; however, the buccal mucosa is not the usual site of occurrence. To date, only 5 articles have been published with 6 cases of epidermoid cysts arising in the buccal mucosa. Therefore, the aim of this study was to describe the clinical, histopathological and immunohistochemical features of a case of an epidermoid cyst located in the buccal mucosa. To our knowledge, this is the first report of an oral epidermoid cyst describing an intense foreign body gigantocellular inflammatory reaction against epithelial keratin component. Although the usual diagnosis for epidermoid cysts is based on histopathological findings, this case report addresses novel information regarding the immunohistochemical pattern which may be found in these lesions.  相似文献   
936.
937.

Objectives

The combination of sodium hypochlorite (NaOCl) and chlorhexidine (CHX) yields a “precipitate potentially toxic” (PPT). The aim of this study was to evaluate the tissue response to implanted polyethylene tubes filled with PPT-soaked fibrin sponge.

Methods

Forty rats received four polyethylene tubes each; each tube was filled with fibrin sponge soaked by 2.5 % NaOCl, 2.0 % CHX, PPT (2.5 % NaOCl plus 2.0 % CHX), or not soaked (control). The observation time points were 7, 15, 30, 60, and 90 days. At each time point, eight animals were killed, and the tubes and surrounding tissues were removed, fixed, and prepared for light microscopic analysis by performing glycol methacrylate embedding, serial cutting into 3-μm sections, and hematoxylin–eosin staining. Qualitative and quantitative evaluations of the reactions were performed. Results were statistically analyzed by Kruskal–Wallis test (p?<?0.05).

Results

All chemical solutions caused moderate reactions at 7 days. On day 30, PPT group was more cytotoxic than the control group and the CHX group (p?<?0.05). On days 15 and 60, PPT group was more cytotoxic than the control group (p?<?0.05). On day 90, there was no statistically significant difference between the different groups.

Conclusion

PPT is more cytotoxic than NaOCl and CHX alone, particularly in the short term.

Clinical significance

Protocols which suggest the use of CHX and NaOCl must be revised because this mixture produces cytotoxic product.  相似文献   
938.
939.
A small cohort of 410 office workers (263 men and 147 women, ever employed) exposed to strong magnetic fields by three 12 kV transformers located beneath their first-floor office developed eight incident cancers over a 15 year exposure period. Only one cancer was ascertained in the 254 workers employed for less than 2 years, compared to seven cancer cases ascertained in the 156 workers employed for 2 years or more (p = 0.0057; Fisher's exact test). An analysis of linear trend of cancer incidence using average years employed as an exposure score was positive (p = 0.00337) with an odds ratio of 15.1 in workers employed over 5 years. A positive trend of cancer cases with duration of employment is seen for males and females separately and together (p < 0.05). For workers employed more than 2 years, the standardized cancer incidence ratio was 389 (95% confidence interval 156–801). Cumulative magnetic field exposure may be of etiologic importance in explaining the cancer incidence pattern in this cohort. © 1996 Wiley-Liss, Inc.  相似文献   
940.
The molecular events involved in the development of esophageal dysplasia and carcinoma are poorly understood. We examined the expression of CD44, a cell-adhesion molecule, in normal and dysplastic epithelia and in squamous-cell carcinoma (SCC) of the esophagus. A monoclonal antibody (MAb) which recognized all CD44 isoforms and 2 MAbs specific to the CD44v3 and CD44v6 splice variants were used to detect CD44 isoforms in 50 archival specimens. A semi-quantitative scoring system based on the extent and intensity of the immunostaining was used to quantify CD44 expression. In normal epithelium, expression of CD44 was strongest in the basal-cell layer and weak or absent in surface cells. Expression of CD44 was increased in dysplastic epithelium as compared with normal epithelium. The extent of this increase correlated directly with the severity of dysplasia. CD44 was expressed in all SCCs, but the extent and intensity of immunostaining varied with areas of tumor differentiation. The well-differentiated components showed greater CD44 expression than the moderately and poorly differentiated components. The patterns of expression of CD44v3 and CD44v6 were strikingly similar to that of total CD44 in normal, dysplastic and malignant esophageal epithelia. Thus, changes in expression of these splice variants likely account to some extent for the changes in total CD44 expression observed in the dysplastic and malignant transformation of the esophagus. Our results suggest that changes in the expression of CD44 may be involved in the development of esophageal dysplasia as well as SCC. © 1996 Wiley-Liss, Inc.  相似文献   
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