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31.
32.

Purpose

This article describes preclinical development of cell-based medicinal products for European markets and discusses European regulatory mechanisms open to developers to aid successful product development. Cell-based medicinal products are diverse, including cells that are autologous or allogeneic, have been genetically modified, or not, or expanded ex vivo, and applied systemically or to an anatomical site different to that of their origin; comments applicable to one product may not be applicable to others, so bespoke development is needed, for all elements - quality, preclinical and clinical.

Methods

After establishing how the product is produced, proof of potential for therapeutic efficacy, and then safety, of the product need to be determined. This includes understanding biodistribution, persistence and toxicity, including potential for malignant transformation. These elements need to be considered in the context of the intended clinical development.

Results

This article describes regulatory mechanisms available to developers to support product development that aim to resolve scientific issues prior to marketing authorization application, to enable patients to have faster access to the product than would otherwise be the case.

Conclusions

Developers are encouraged to be aware of both the scientific issues and regulatory mechanisms to ensure patients can be supplied with these products.
  相似文献   
33.
The spread of antimicrobial resistance challenges the empirical treatment of urinary tract infections (UTIs). Among others, nitrofurantoin is recommended for first-line treatment, but acceptance among clinicians is limited due to chronic nitrofurantoin-induced lung toxicity and insufficient coverage of Enterobacteriaceae other than Escherichia coli. Nitroxoline appears to be an alternative to nitrofurantoin owing to its favourable safety profile, however data on its current in vitro susceptibility are sparse. In this study, susceptibility to nitroxoline was tested against 3012 urinary clinical isolates (including multidrug-resistant bacteria and Candida spp.) by disk diffusion test and/or broth microdilution. At least 91% of all Gram-negatives (n?=?2000), Gram-positives (n?=?403) and yeasts (n?=?132) had inhibition zone diameters for nitroxoline ≥18?mm. Except for Pseudomonas aeruginosa, nitroxoline MIC90 values were ≤16?mg/L and were 2- to >16-fold lower compared with nitrofurantoin. In extended-spectrum β-lactamase (ESBL)-producing Enterobacteriaceae and methicillin-resistant Staphylococcus aureus (MRSA), MIC90 values of nitroxoline were two-fold higher compared with non-ESBL-producing enterobacteria and methicillin-susceptible S. aureus (MSSA). The in vitro efficacies of nitroxoline and nitrofurantoin against ATCC strains of E. coli, Enterococcus faecalis and Proteus mirabilis were compared by time–kill curves in Mueller–Hinton broth and artificial urine. Nitroxoline was non-inferior against E. coli, P. mirabilis and E. faecalis in artificial urine. In conclusion, nitroxoline showed a broad antimicrobial spectrum, with inhibition zone diameters and MICs of nitroxoline well below the EUCAST breakpoint for E. coli for most organisms, and thus may also be a target for therapy of uncomplicated UTIs.  相似文献   
34.
Increased functional brain response towards alcohol-associated stimuli is a neural hallmark of alcohol dependence and a promising target for pharmacotherapy. For the first time, we assessed the effects of individually titrated high-dose baclofen on cue reactivity and functional connectivity in alcohol-dependent (AD) patients in a randomized controlled trial (RCT).We investigated 23 recently detoxified AD patients and 23 matched healthy controls (HC) with a cue reactivity functional magnetic resonance imaging task. Patients were further scanned at baseline without medication and during treatment with high-dose baclofen/placebo (30–270 mg/d). Analyses were conducted for alcohol cue-elicited brain response, alcohol cue-modulated and stimulus-independent functional connectivity with left ventral tegmental area (VTA) as seed region.At baseline, AD patients (N?=?23) showed increased cue-elicited brain activation in the ventral striatum (VS) compared to HC (N?=?23), which was decreased at the second scanning session compared to baseline. Patients receiving baclofen (N?=?10) showed a significant stronger decrease in cue-elicited brain activation in left orbitofrontal cortex (OFC), bilateral amygdala and left VTA than patients receiving placebo (N?=?13). Treatment with baclofen further led to a decrease in alcohol cue-modulated functional connectivity between left VTA and left anterior cingulate cortex (ACC) as well as left medial prefrontal cortex (MPFC). Regarding clinical outcome, significantly more patients of the baclofen group remained abstinent during the high-dose period.Baclofen specifically decreased cue-elicited brain responses in areas known to be involved in the processing of salient (appetitive and aversive) stimuli. Treatment with high-dose baclofen seems to provide a pharmacological relief of this neural “warning signal” evoked by alcohol-related cues, thereby possibly supporting patients in remaining abstinent.Trial Registration Identifier of the main trial [BACLAD study] at clinicaltrials.gov: NCT01266655.  相似文献   
35.
中文:背景患者入院后可从不当消毒的环境表面获得多药耐药菌和艰难梭菌。本文确定了3种强化的终末消毒(入住同一病房的两名患者之间的消毒)策略,对感染耐甲氧西林金黄色葡萄球菌(MRSA)、耐万古霉素肠球菌(VRE)、艰难梭菌(CD)和多重耐药不动杆菌的影响。方法本文在美国东南部的9家医院开展了一项务实的、集群-随机、交叉研究。凡曾有感染或定植目标细菌感染患者居住过的病房,患者出院后随机采取4种消毒策略中的一种方法进行终末消毒:对照(季胺盐类消毒剂消毒,但凡遇到CD采用含氯消毒剂);UV(季胺盐类+UV-C消毒,但凡遇到CD采用含氯消毒剂+UV-C);含氯消毒剂;含氯消毒剂+UV-C。凡入住目标病房的患者被列为暴露人群。这4种终末消毒方法分别在每家医院连续实施7个月的周期。本文随机设计这几种消毒策略在每家医院内的实施顺序(1:1:1:1)。主要产出的结果是,观察暴露患者中目标细菌的感染的发生或定植情况,以及ITT人群中暴露患者CD感染发生率。本研究ClinicalTrials.gov注册编号:NCT01579370。结果共有31 226名患者暴露,其中21 395(69%)符合标准,包括4 916名对照组,5 178名UV组,5 438名含氯消毒剂组,以及5 863名含氯消毒剂+UV组。在对照组中,22 426个暴露日中有115名患者发生目标细菌的感染(51.3/10000暴露日)。在标准清洁策略的基础上增加UV消毒的暴露患者,其目标细菌感染的发生率明显较低(n=76;33.9/10 000暴露日;RR:0.70,95%CI:0.50~0.988;P=0.036)。含氯消毒剂组(n=101;41.6/10 000暴露日;RR:0.85,95%CI:0.69~1.04;P=0.116),或含氯消毒剂+UV组患者(n=131;45.6/10 000暴露日;RR:0.91,95%CI:0.76~1.09;P=0.303)的目标细菌的感染率,其差异无统计学意义。同样,在含氯消毒剂的基础上增加UV消毒,暴露患者中CD感染率也没有发生改变((n=38 vs 36;30.4 vs 31.6/10 000暴露日;RR:1.0,95%CI:0.57-1.75;P=0.997)。解释污染的医疗机构环境是获得病原微生物的重要来源;强化终末消毒可以降低这一风险。  相似文献   
36.
37.

Purpose

Most computerized adaptive testing (CAT) applications in patient-reported outcomes (PRO) measurement to date are reliability-centric, with a primary objective of maximizing measurement efficiency. A key concern and a potential threat to validity is that, when left unconstrained, individual CAT administrations could have items with systematically different attributes, e.g., sub-domain coverage. This paper aims to provide a solution to the problem from an optimal test design framework using the shadow-test approach to CAT.

Methods

Following the approach, a case study was conducted using the PROMIS® (Patient-Reported Outcomes Measurement Information System) fatigue item bank both with empirical and simulated response data. Comparisons between CAT administrations without and with the enforcement of content and item pool usage constraints were examined.

Results

The unconstrained CAT exhibited a high degree of variation in items selected from different substrata of the item bank. Contrastingly, the shadow-test approach delivered CAT administrations conforming to all specifications with a minimal loss in measurement efficiency.

Conclusions

The optimal test design and shadow-test approach to CAT provide a flexible framework for solving complex test-assembly problems with better control of their domain coverage than for the conventional use of CAT in PRO measurement. Applications in a wide array of PRO domains are expected to lead to more controlled and balanced use of CAT in the field.
  相似文献   
38.
39.
The list of motives by Kanin (1994) is the most cited list of motives to file a false allegation of rape. Kanin posited that complainants file a false allegation out of revenge, to produce an alibi or to get sympathy. A new list of motives is proposed in which gain is the predominant factor. In the proposed list, complainants file a false allegation out of material gain, emotional gain, or a disturbed mental state. The list can be subdivided into eight different categories: material gain, alibi, revenge, sympathy, attention, a disturbed mental state, relabeling, or regret. To test the validity of the list, a sample of 57 proven false allegations were studied at and provided by the National Unit of the Dutch National Police (NU). The complete files were studied to ensure correct classification by the NU and to identify the motives of the complainants. The results support the overall validity of the list. Complainants were primarily motivated by emotional gain. Most false allegations were used to cover up other behavior such as adultery or skipping school. Some complainants, however, reported more than one motive. A large proportion, 20% of complainants, said that they did not know why they filed a false allegation. The results confirm the complexity of motivations for filing false allegations and the difficulties associated with archival studies. In conclusion, the list of Kanin is, based on the current results, valid but insufficient to explain all the different motives of complainants to file a false allegation.  相似文献   
40.
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