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961.
BackgroundThe association of age with coronary plaque dynamics is not well characterized by coronary computed tomography angiography (CCTA).MethodsFrom a multinational registry of patients who underwent serial CCTA, 1153 subjects (61 ± 5 years old, 61.1% male) were analyzed. Annualized volume changes of total, fibrous, fibrofatty, necrotic core, and dense calcification plaque components of the whole heart were compared by age quartile groups. Clinical events, a composite of all-cause death, acute coronary syndrome, and any revascularization after 30 days of the initial CCTA, were also analyzed. Random forest analysis was used to define the relative importance of age on plaque progression.ResultsWith a 3.3-years’ median interval between the two CCTA, the median annual volume changes of total plaque in each age quartile group was 7.8, 10.5, 10.8, and 12.1 mm3/year and for dense calcification, 2.5, 4.6, 5.4, and 7.1 mm3/year, both of which demonstrated a tendency to increase by age (p-for-trend = 0.001 and < 0.001, respectively). However, this tendency was not observed in any other plaque components. The annual volume changes of total plaque and dense calcification were also significantly different in the propensity score-matched lowest age quartile group versus the other age groups as was the composite clinical event (log-rank p = 0.003). In random forest analysis, age had comparable importance in the total plaque volume progression as other traditional factors.ConclusionsThe rate of whole-heart plaque progression and dense calcification increases depending on age. Age is a significant factor in plaque growth, the importance of which is comparable to other traditional risk factors.Clinical trial registrationURL: http://www.clinicaltrials.gov. Unique identifiers: NCT02803411.  相似文献   
962.
The COVID-19 pandemic has affected patient care deliver throughout the world, resulting in a greater emphasis on efficiently and safety. In this article, we discuss the experiences of several North American centers in utilizing cardiac CT during the pandemic. We also provide a case-based overview which highlights the advantages of cardiac CT in evaluating the following scenarios: (1) patients with possible myocardial injury versus myocardial infarction; (2) patients with acute chest pain; (3) patients with stable chest pain; (4) patients with possible intracardiac thrombus; (5) patients with valvular heart disease. For each scenario, we also provide an overview of various societies recommendations which have highlighted the use of cardiac CT during different phases of the COVID-19 pandemic. We hope that the advantages of cardiac CT that have been realized during the pandemic can help promote wider adoption of this technique and improved coverage and payment by payors.  相似文献   
963.
The common preference of cancers for lactic acid‐generating metabolic energy pathways has led to proposals that their reprogrammed metabolism confers growth advantages such as decreased susceptibility to hypoxic stress. Recent observations, however, suggest that it generates a novel way for cancer survival. There is increasing evidence that cancers can escape immune destruction by suppressing the anti‐cancer immune response through maintaining a relatively low pH in their micro‐environment. Tumours achieve this by regulating lactic acid secretion via modification of glucose/glutamine metabolisms. We propose that the maintenance by cancers of a relatively low pH in their micro‐environment, via regulation of their lactic acid secretion through selective modification of their energy metabolism, is another major mechanism by which cancers can suppress the anti‐cancer immune response. Cancer‐generated lactic acid could thus be viewed as a critical, immunosuppressive metabolite in the tumour micro-environment rather than a ‘waste product’. This paradigm shift can have major impact on therapeutic strategy development. Copyright © 2013 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.  相似文献   
964.
Chromosome 11q13.5 containing RSF1 (HBXAP), a gene involved in chromatin remodelling, is amplified in several human cancers including ovarian carcinoma. Our previous studies demonstrated requirement of Rsf‐1 for cell survival in cancer cells, which contributed to tumour progression; however, its role in tumourigenesis has not yet been elucidated. In this study, we co‐immunoprecipitated proteins with Rsf‐1 followed by nanoelectrospray mass spectrometry and identified cyclin E1, besides SNF2H, as one of the major Rsf‐1 interacting proteins. Like RSF1, CCNE1 is frequently amplified in ovarian cancer, and both Rsf‐1 and cyclin E1 were found co‐up‐regulated in ovarian cancer tissues. Ectopic expression of Rsf‐1 and cyclin E1 in non‐tumourigenic TP53mut RK3E cells led to an increase in cellular proliferation and tumour formation by activating cyclin E1‐associated kinase (CDK2). Tumourigenesis was not detected if either cyclin E1 or Rsf‐1 was expressed, or they were expressed in a TP53wt background. Domain mapping showed that cyclin E1 interacted with the first 441 amino acids of Rsf‐1. Ectopic expression of this truncated domain significantly suppressed G1/S‐phase transition, cellular proliferation, and tumour formation of RK3E‐p53R175H/Rsf‐1/cyclin E1 cells. The above findings suggest that Rsf‐1 interacts and collaborates with cyclin E1 in neoplastic transformation and TP53 mutations are a prerequisite for tumour‐promoting functions of the RSF/cyclin E1 complex.  相似文献   
965.
Bacteriophage chi is a well-known phage that infects pathogens such as E. coli, Salmonella, and Serratia via bacterial flagella. To further understand its host-phage interaction and infection mechanism via host flagella, the genome was completely sequenced and analyzed. The phage genome contains 59,407-bp-length DNA with a GC content of 56.51 %, containing 75 open reading frames (ORFs) with no tRNA genes. Its annotation and functional analysis revealed that chi is evolutionarily very closely related to Enterobacter phage Enc34 and Providencia phage Redjac. However, most of the annotated genes encode hypothetical proteins, indicating that further genomic study of phage chi is required to elucidate the bacterial-flagellum-targeting infection mechanism of phage chi.  相似文献   
966.
967.

Purpose

Although there is no clinical evidence of nephrotoxicity with the volatile anesthetics currently used in general anesthesia, a better agent should be needed in terms of preserving postoperative renal function in living kidney donors who have only single remaining kidney. The purpose of the current retrospective, single-center study was to evaluate and compare renal function of living kidney donors after nephrectomy under either sevoflurane or desflurane anesthesia.

Materials and Methods

From January 2006 through December 2011, a total of 228 donors undergoing video assisted minilaparotomy surgery nephrectomy for kidney donation were retrospectively enrolled in the current study. The donors were categorized into a sevoflurane group or desflurane group based on the type of volatile anesthetic used. We collected laboratory data from the patients preoperatively, immediately after the operation, on the first postoperative day and on the third postoperative day. We also compared renal function of the kidney donors after donor nephrectomy by comparing creatinine level and estimated glomerular filtration rate (eGFR).

Results

The decrease in renal function after surgery in both groups was the most prominent on the first postoperative day. There were no significant differences between the two groups in postoperative changes of creatinine or eGFR.

Conclusion

Sevoflurane and desflurane can be used safely as volatile anesthetics in donors undergoing nephrectomy.  相似文献   
968.

Purpose

Currently, insufficient data exist to evaluate the relationship between angiographic late loss (LL) and long-term clinical outcome after drug-eluting stent (DES) implantation. In this study, we hypothesized that angiographic LL between 0.3 and 0.6 mm correlate with favorable long-term clinical outcomes.

Materials and Methods

Patients were enrolled in the present study if they had undergone both DES implantation in single coronary vessel and a subsequent follow-up angiogram (n=634). These individuals were then subdivided into three groups based on their relative angiographic LL: group I (angiographic LL <0.3 mm, n=378), group II (angiographic LL between 0.3 and 0.6 mm, n=124), and group III (angiographic LL >0.6 mm, n=134). During a 5-year follow-up period, all subjects were tracked for critical events, defined as any cause of death or myocardial infarction, which were then compared among the three groups.

Results

Mean follow-up duration was 63.0±10.0 months. Critical events occurred in 25 subjects in group I (6.6%), 5 in group II (4.0%), and 17 in group III (12.7%), (p=0.020; group I vs. group II, p=0.293; group II vs. group III, p=0.013). In a subsequent multivariate logistic regression analysis, chronic renal failure [odds ratio (OR)=3.29, 95% confidence interval (CI): 1.48-7.31, p=0.003] and long lesion length, defined as lesion length >28 mm (OR=1.88, 95% CI: 1.02-3.46, p=0.042) were independent predictors of long-term critical events.

Conclusion

This retrospective analysis fails to demonstrate that post-DES implantation angiographic LL between 0.3 and 0.6 mm is protective against future critical events.  相似文献   
969.

Purpose

To investigate the ultrasonographic (US) features of anaplastic thyroid cancer (ATC) and the diagnostic performance of US-guided fine needle aspiration biopsy (FNAB) therein.

Materials and Methods

Eighteen cases of ATC diagnosed between January 2001 and May 2011 were included. FNAB was performed in all cases. Initial FNAB results were divided into three groups: 1) the cytological ATC group, cytological diagnosis of ATC; 2) the underestimated group, cytological diagnoses of malignancy other than ATC; and 3) the false negative group, cytological diagnoses of atypical, benign and non-diagnostic lesions. We retrospectively reviewed US findings and compared treatment modalities between each group.

Results

Among the 18 patients, there were nine in the initially cytological ATC group, four in the underestimated group and five in the false negative group. The most common US features of ATC were a solid (64.7%) and irregular shaped (88.2%) mass with lymph node involvement (76.4%). However, except for lymph node involvement (p=0.003), US findings for each group were not statistically different. The initial cytological diagnostic accuracy of ATC was 50% (9/18). Surgery was performed less in the ATC group (11%) and the false negative group (20%) than the underestimated group (75%).

Conclusion

The US features of ATC were not especially different from other types of aggressive thyroid cancer. A correct diagnosis of ATC by initial US-FNAB was made in 50% of the patients, which is significant in that therapeutic surgery can be undertaken in lower numbers if correctly diagnosed.  相似文献   
970.

Purpose

To investigate the effect of pretreatment with intravenous nicorandil on the incidence of contrast-induced nephropathy (CIN) in patients with renal dysfunction undergoing coronary angiography.

Materials and Methods

This randomized controlled multicenter study enrolled a total of 166 patients (nicorandil n=81; control n=85) with an estimated glomerular filtration rate <60 mL/min. Nicorandil 12 mg dissolved in 100 mL of 0.9% saline was administered intravenously for 30 minutes just prior to coronary angiography in the nicorandil group. The same volume of only saline was given to the control group. The primary end-point was the incidence of CIN, defined as >0.5 mg/dL increase or >25% rise in serum creatinine (SCr) concentration within 48 hours of contrast exposure compared to baseline.

Results

The final analysis included 149 patients (nicorandil n=73; control n=76). The baseline characteristics and the total volume of the used contrast (Iodixanol, 125.6±69.1 mL vs. 126.9±74.6 mL, p=0.916) were similar between the two groups. The incidence of CIN also did not differ between the nicorandil and control groups (6.8% vs. 6.6%, p=0.794). There was no difference between the two groups in the relative change in SCr from baseline to peak level within 48 hours after coronary angiography (-1.58±24.07% vs. 0.96±17.49%, p=0.464), although the nicorandil group showed less absolute change in SCr than the control group (-0.01±0.43 mg/mL vs. 0.02±0.31 mg/mL, p=0.005).

Conclusion

Prophylactic intravenous infusion of nicorandil did not decrease the incidence of CIN in patients with renal dysfunction undergoing coronary angiography.  相似文献   
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