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11.
The Cerebellum - Upward and downward bias of eye movement signals in the semicircular canals (SCC)- and/or otolith-related central pathways have been proposed to explain the occurrence of vertical...  相似文献   
12.
Background:Transcatheter aortic valve replacement (TAVR) is a worldwide adopted procedure with rapidly evolving practices. Regional and temporal variations are expected to be found.Objective:To compare TAVR practice in Latin America with that around the world and to assess its changes in Latin America from 2015 to 2020.Methods:A survey was applied to global TAVR centers between March and September 2015, and again to Latin-American centers between July 2019 and January 2020. The survey consisted of questions addressing: i) center’s general information; ii) pre-TAVR evaluation; iii) procedural techniques; iv) post-TAVR management; v) follow-up. Answers from the 2015 survey of Latin-American centers (LATAM15) were compared with those of other centers around the world (WORLD15) and with the 2020 updated Latin-American survey (LATAM20). A 5% level of significance was adopted for statistical analysis.Results:250 centers participated in the 2015 survey (LATAM15=29; WORLD15=221) and 46 in the LATAM20. Combined centers experience accounted for 73 707 procedures, with WORLD15 centers performing, on average, 6- and 3-times more procedures than LATAM15 and LATAM20 centers, respectively. LATAM centers performed less minimalistic TAVR than WORLD15 centers, but there was a significant increase in less invasive procedures after 5 years in Latin-American centers. For postprocedural care, a lower period of telemetry and maintenance of temporary pacing wire, along with less utilization of dual antiplatelet therapy was observed in LATAM20 centers.Conclusion:Despite still having a much lower number of procedures, many aspects of TAVR practice in Latin-American centers have evolved in recent years, followingthe trend observed in developed country centers.  相似文献   
13.
CONTEXT: The Thrombolysis in Myocardial Infarction (TIMI) risk score for ST-elevation myocardial infarction (STEMI) is a simple integer score for bedside risk assessment of patients with STEMI. Developed and validated in multiple clinical trials of fibrinolysis, the risk score has not been validated in a community-based population. OBJECTIVE: To validate the TIMI risk score in a population of STEMI patients reflective of contemporary practice. DESIGN, SETTING, AND PARTICIPANTS: The risk score was evaluated among 84 029 patients with STEMI from the National Registry of Myocardial Infarction 3 (NRMI 3), which collected data on consecutive patients with myocardial infarction (MI) from 1529 US hospitals between April 1998 and June 2000. MAIN OUTCOME MEASURES: Ability of the TIMI risk score to correctly predict risk of death in terms of model discrimination (c statistic) and calibration (agreement of predicted and observed death rates). RESULTS: Patients in NRMI 3 tended to be older, to be more often female, and to have a history of coronary disease more often than those in the derivation set. Forty-eight percent received reperfusion therapy. The TIMI risk score revealed a significant graded increase in mortality with rising score (range, 1.1%-30.0%; P<.001 for trend). The risk score showed strong prognostic capacity overall (c = 0.74 vs 0.78 in derivation set) and among patients receiving acute reperfusion therapy (c = 0.79). Predictive behavior of the risk score was similar between fibrinolytic-treated patients (n = 23 960; c = 0.79) and primary percutaneous coronary intervention patients (n = 15 348; c = 0.80). In contrast, among patients not receiving reperfusion therapy, the risk score underestimated death rates and offered lower discriminatory capacity (c = 0.65). CONCLUSIONS: Sufficiently simple to be practical at the bedside and effective for risk assessment across a spectrum of patients, the TIMI risk score may be useful in triage and treatment of patients with STEMI who are treated with reperfusion therapy.  相似文献   
14.
Funnel web spider toxin (FTX) is reportedly a specific blocker of P-type Ca2+ channels. The effects of FTX on the Ca2+ currents of isolated neurohypophysial nerve terminals of the rat were investigated using the ‘whole-cell’ patch-clamp technique. Both the transient and long-lasting Ca2+ current components were maximally elicited by depolarization from a holding potential equal to the normal terminal resting potential (−90 mV). Externally applied FTX inhibited the high-voltage-threshold, transient component of the Ca2+ current in a concentration-dependent manner, with a half-maximal inhibition at a dilution of approximately 1: 10000. FTX also shifted the peak current of the I–V relationship by + 10 mV. The long-lasting Ca2+ current component, which is sensitive to L-type Ca2+ channel blockers, was insensitive to FTX. The transient current, which is sensitive to ω-conotoxin GVIA, was completely blocked by FTX. These results suggest that there could be a novel, inactivating Ca2+ channel in the rat neurohypophysial terminals which is affected by both N-type and P-type Ca2+ channel blockers.  相似文献   
15.

INTRODUCTION:

In elderly patients with acute myocardial infarction, very little is known about the role of surgical myocardial revascularization and percutaneous coronary intervention (invasive therapies - IT), especially in the context of long-term outcomes after hospital discharge.

METHODS:

We analyzed 1588 patients with MI who had been included prospectively in a databank and followed for up to 7.5 years. In this population, 548 patients were ≥70 years old (elderly group - EG), and 1040 were <70 years of age (younger group - YG); 1088 underwent IT during hospitalization, and the remaining 500 were treated medically (conservative therapy - CT). Patients were monitored either by visit or by phone at least once a year. A standard questionnaire was administered to all patients. The impact of IT was analyzed with both non-adjusted and adjusted models.

RESULTS:

By the end of the follow-up period, the survival rates for the IT and CT groups were, respectively, 71.9% versus 47.2% in the global population (hazard ratio=0.55, P<0.001), 81.5% versus 66.6% in the YG (hazard ratio=0.68, P=0.018) and 48.8% versus 20.3% in the EG (hazard ratio=0.58, P<0.001). In the adjusted models, the hazard ratios were 0.62 (P<0.001) in the global population, 0.74 in the YG (P=0.073) and 0.64 (P=0.001) in the EG.

CONCLUSION:

Long-term follow-up of patients with myocardial infarction revealed that IT during the in-hospital phase was at least as effective in elderly patients as in younger patients.  相似文献   
16.
Primary familial brain calcification (PFBC) is a heterogeneous neuropsychiatric disorder, with affected individuals presenting a wide variety of motor and cognitive impairments, such as migraine, parkinsonism, psychosis, dementia, and mood swings. Calcifications are usually symmetrical, bilateral, and found predominantly in the basal ganglia, thalamus, and cerebellum. So far, variants in three genes have been linked to PFBC: SLC20A2, PDGFRB, and PDGFB. Variants in SLC20A2 are responsible for most cases identified so far and, therefore, the present review is a comprehensive worldwide summary of all reported variants to date. SLC20A2 encodes an inorganic phosphate transporter, PiT‐2, widely expressed in various tissues, including brain, and is part of a major family of solute carrier membrane transporters. Fifty variants reported in 55 unrelated patients so far have been identified in families of diverse ethnicities and only few are recurrent. Various types of variants were detected (missense, nonsense, frameshift) including full or partial SLC20A2 deletions. The recently reported SLC20A2 knockout mouse will enhance our understanding of disease mechanism and allow for screening of therapeutic compounds. In the present review, we also discuss the implications of these recent exciting findings and consider the possibility of treatments based on manipulation of inorganic phosphate homeostasis.  相似文献   
17.
Streptococcus mutans is the etiological agent of dental caries and one of the many bacterial species implicated in infective endocarditis. The expression of the collagen-binding protein Cnm by S. mutans has been associated with extraoral infections, but its relevance for dental caries has only been theorized to date. Due to the collagenous composition of dentinal and root tissues, we hypothesized that Cnm may facilitate the colonization of these surfaces, thereby enhancing the pathogenic potential of S. mutans in advancing carious lesions. As shown for extraoral endothelial cell lines, Cnm mediates the invasion of oral keratinocytes and fibroblasts by S. mutans. In this study, we show that in the Cnm+ native strain, OMZ175, Cnm mediates stringent adhesion to dentinal and root tissues as well as collagen-coated surfaces and promotes both cariogenicity and carriage in vivo. In vitro, ex vivo, and in vivo experiments revealed that while Cnm is not universally required for S. mutans cariogenicity, it contributes to (i) the invasion of the oral epithelium, (ii) enhanced binding on collagenous surfaces, (iii) implantation of oral biofilms, and (IV) the severity of caries due to a native Cnm+ isolate. Taken together, our findings reveal that Cnm is a colonization factor that contributes to the pathogenicity of certain S. mutans strains in their native habitat, the oral cavity.  相似文献   
18.
19.
The present study aimed to correlate morphometric parameters of the oocytes with the occurrence of fertilization following intracytoplasmic sperm injection (ICSI). In a prospective, controlled cohort design, women (n = 32) who were candidates for ICSI had oocytes (n = 258) collected and submitted to morphometric evaluation using the Cronus3 software program. The morphometric parameters obtained were oocyte diameter, perivitelline space width, zona pellucida thickness, and first polar body diameter. The median oocyte diameter was similar in cases in which fertilization occurred compared with those in which fertilization failed (75.2 and 75.9 μm, respectively; P = .218). The 2 groups also had similar measurements of perivitelline space, zona pellucida, and first polar body. However, the best quality zygotes identified by a morphological score resulted from oocytes with larger diameter (75.6 vs 74.0 μm; P < .01) and narrow perivitelline space (5.3 vs 7.1 μm; P < .01). Embryo development, as assessed by cleavage at second day of culture, was not significantly associated with oocyte morphometric parameters. These findings suggest that morphometric parameters of the oocytes do not correlate with the occurrence of fertilization following ICSI but may assist in selecting oocytes more likely to originate high-quality zygotes.  相似文献   
20.

Objective

To evaluate the association of intimate partner violence during the gestational period and the development of externalizing and internalizing behavioral problems in children and adolescents.

Source of data

A meta-analysis of cohort and case–control studies was performed, using studies selected from electronic databases. Eligible studies included women who experienced intimate partner violence during pregnancy and their children's behavioral problems. These problems encompass two groups: externalizing problems (expressed by hyperactivity, aggressive and challenging behavior, and delinquency) and internalizing problems (represented by depressive moods, anxiety, and somatic symptoms). The risk of bias was assessed by the Newcastle-Ottawa Quality Assessment Scale (NOS) and the quality of evidence by the Grading of Recommendations, Assessment, Development and Evaluation (GRADE). RevMan 5.3 software was used for the meta-analysis.

Data synthesis

Of the 687 eligible articles, only seven met all inclusion criteria and consisted of 12,250 mother/child pairs. The age range of the assessed children varied from 10 months to 16 years. The odds of internalizing problems in children exposed to prenatal violence were two-fold higher (OR = 2.10, 95% CI: 1.17–3.76) and that of externalizing problems were 1.9-fold higher (95% CI: 1.28–2.83), when compared to children of unexposed mothers.

Conclusion

The results of this study are consistent with the hypothesis that women's exposure to intimate partner violence during pregnancy may be associated with behavioral problems of their children, emphasizing the need for greater understanding about the vulnerability of children to adversity in early ages.  相似文献   
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