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41.
ObjectivesNon-traditional materials are used for mask construction to address personal protective equipment shortages during the coronavirus disease 2019 (COVID-19) pandemic. Reusable masks made from surgical sterilization wrap represent such an innovative approach with social media frequently referring to them as “N95 alternatives.” This material was tested for particle filtration efficiency and breathability to clarify what role they might have in infection prevention and control.MethodsA heavyweight, double layer sterilization wrap was tested when new and after 2, 4, 6, and 10 autoclave sterilizing cycles and compared with an approved N95 respirator and a surgical mask via testing procedures using a sodium chloride aerosol for N95 efficiency testing similar to 42 CFR 84.181. Pressure testing to indicate breathability was also conducted.ResultsThe particle filtration efficiency for the sterilization wrap ranged between 58% to 66%, with similar performance when new and after sterilizing cycles. The N95 respirator and surgical mask performed at 95% and 68% respectively. Pressure drops for the sterilization wrap, N95 and surgical mask were 10.4 mmH2O, 5.9 mmH2O, and 5.1 mmH2O, respectively, well below the National Institute for Occupational Safety and Health limits of 35 mmH2O during initial inhalation and 25 mmH2O during initial exhalation.ConclusionsThe sterilization wrap’s particle filtration efficiency is much lower than a N95 respirator, but falls within the range of a surgical mask, with acceptable breathability. Performance testing of non-traditional mask materials is crucial to determine potential protection efficacy and for correcting misinterpretation propagated through popular media. 相似文献
42.
Franois-Xavier Briand Eric Niqueux Audrey Schmitz Claire Martenot Martine Cherbonnel Pascale Massin Florian Kerbrat Marina Chatel Carole Guillemoto Cecile Guillou-Cloarec Katell Ogor Aurlie Le Prioux Chantal Alle Vronique Beven Edouard Hirchaud Yannick Blanchard Axelle Scoizec Sophie Le Bouquin Nicolas Eterradossi Batrice Grasland 《Emerging infectious diseases》2021,27(2):508
We detected 3 genotypes of highly pathogenic avian influenza A(H5N8) virus in France during winter 2016–17. Genotype A viruses caused dramatic economic losses in the domestic duck farm industry in southwestern France. Our phylogenetic analysis suggests that genotype A viruses formed 5 distinct geographic clusters in southwestern France. In some clusters, local secondary transmission might have been started by a single introduction. The intensity of the viral spread seems to correspond to the density of duck holdings in each production area. To avoid the introduction of disease into an unaffected area, it is crucial that authorities limit the movements of potentially infected birds. 相似文献
43.
Dimitrios Moris Brian I. Shaw Cecilia Ong Ashton Connor Mariya L. Samoylova Samuel J. Kesseli Nader Abraham Jared Gloria Robin Schmitz Zachary W. Fitch Bryan M. Clary Andrew S. Barbas 《肝胆外科与营养》2021,10(3):315
BackgroundSelection of the optimal treatment modality for primary liver cancers remains complex, balancing patient condition, liver function, and extent of disease. In individuals with preserved liver function, liver resection remains the primary approach for treatment with curative intent but may be associated with significant mortality. The purpose of this study was to establish a simple scoring system based on Model for End-stage Liver Disease (MELD) and extent of resection to guide risk assessment for liver resections.MethodsThe 2005–2015 NSQIP database was queried for patients undergoing liver resection for primary liver malignancy. We first developed a model that incorporated the extent of resection (1 point for major hepatectomy) and a MELD-Na score category of low (MELD-Na =6, 1 point), medium (MELD-Na =7–10, 2 points) or high (MELD-Na >10, 3 points) with a score range of 1–4, called the Hepatic Resection Risk Score (HeRS). We tested the predictive value of this model on the dataset using logistic regression. We next developed an optimal multivariable model using backwards sequential selection of variables under logistic regression. We performed K-fold cross validation on both models. Receiver operating characteristics were plotted and the optimal sensitivity and specificity for each model were calculated to obtain positive and negative predictive values.ResultsA total of 4,510 patients were included. HeRS was associated with increased odds of 30-day mortality [HeRS =2: OR =3.23 (1.16–8.99), P=0.025; HeRS =3: OR =6.54 (2.39–17.90), P<0.001; HeRS =4: OR =13.69 (4.90–38.22), P<0.001]. The AUC for this model was 0.66. The AUC for the optimal multivariable model was higher at 0.76. Under K-fold cross validation, the positive predictive value (PPV) and negative predictive value (NPV) of these two models were similar at PPV =6.4% and NPV =97.7% for the HeRS only model and PPV =8.4% and NPV =98.1% for the optimal multivariable model.ConclusionsThe HeRS offers a simple heuristic for estimating 30-day mortality after resection of primary liver malignancy. More complicated models offer better performance but at the expense of being more difficult to integrate into clinical practice. 相似文献
44.
Schmitz Timo Meisinger Christa Kirchberger Inge Thilo Christian Amann Ute Baumeister Sebastian E. Linseisen Jakob 《European journal of epidemiology》2021,36(6):619-627
European Journal of Epidemiology - The aim of this study was to evaluate the impact of the COVID-19 pandemic lockdown on acute myocardial infarction (AMI) care, and to identify underlying stressors... 相似文献
45.
The effect of systemic glucocorticoid therapy on immune parameters was studied in patients with bronchial asthma. Patients were divided into two groups: 1) those receiving oral glucocorticoid; 2) control patients who did not receive systemic glucocorticoid treatment. The glucocorticoid dose varied between 5 and 70 mg per day. Patients had been taking oral therapy for at least 1 year. Glucocorticoid treatment was associated with an increased frequency of respiratory tract infections. Therefore, we need to define immune parameters which may predict an increased risk of infections. In this study, we analyzed several surface markers on lymphocytes and monocytes by flow cytometry. A significant reduction of the ratio of peripheral blood CD4+ to CD8+ T cells was associated with the administration of oral glucocorticoids. Furthermore, the expression of the HLA-DR molecule on monocytes was reduced in patients with systemic glucocorticoid therapy compared to control patients. Moreover, the capacity to elaborate cytokines by peripheral blood mononuclear cells upon stimulation was greatly reduced after exposure to glucocorticoids in vivo and in vitro. In addition, the humoral immune response was affected, because reduced IgG, IgM, and IgA levels were observed in patients receiving oral glucocorticoids. These results indicate that systemic glucocorticoid treatment in patients with bronchial asthma is associated with cellular and humoral immunosuppression which results in an increased risk of bacterial and viral infections. 相似文献
46.
Antibiotics for treatment of infections caused by MRSA and elimination of MRSA carriage. What are the choices? 总被引:1,自引:0,他引:1
The widespread appearance of methicillin resistant Staphylococcus aureus (MRSA) has significantly undermined the efficacy of currently available antibiotic therapies as strains tend to be multi-resistant. Clinicians are therefore faced with a restricted choice in effective anti-MRSA therapies for infection or elimination of carriage. MRSA remain uniformly susceptible to glycopeptides vancomycin and teicoplanin which remain drugs of choice in treatment of infections. Centres with a high incidence of MRSA should use glycopeptides as empirical monotherapies against these organisms. The low toxicity of teicoplanin makes it an alternative for patients unable to tolerate vancomycin. Only mupirocin is truly effective for use as a topical agent in elimination of MRSA colonisation. For systemic use developmental glycopeptides such as daptomycin, MDL 63246, and LY191145 show better in vitro activity than vancomycin. New cephalosporins TOC-39 and FK-037 show promising anti-MRSA potential with low MICs, as does carbapenem BO-2727 which has a high in vitro activity. Whether the new cephalosporins and carbapenems with good in vitro and/or in vivo activities against MRSA will be clinically effective remains to be determined. New fluoroquinolones levofloxacin, temafloxacin and sparfloxacin have enhanced in vitro anti-MRSA activity, although the emergence of resistance, and subsequent cross resistance to related compounds during therapy is a problem. BAY 12-8039, DV-7751 and CS-940 are developmental fluoroquinolones with better in vitro activity and lower spontaneous mutation rates than related compounds. Co-trimoxazole shows good in vivo anti-MRSA activity, comparable to vancomycin, however, severe infections do not respond well and many strains are resistant to this drug. Rifampicin has excellent bactericidal activity but rapidly emerging resistance undermines its use as a monotherapy. Its use in a combination therapy offers limited potential as an alternative. Arbekacin shows good in vitro activity against many MRSA isolates, although resistance to related aminoglycosides is a problem. Streptogramins, virginiamicin and RP 59500 (dalfopristin/quinupristin), and the everninomicin SCH 27899, show excellent activity in vitro and in vivo activity against MRSA and real future potential as alternative agents to vancomycin. Azeleic acid and ramoplanin show future potential as agents for topical use against MRSA. In conclusion only vancomycin as a systemic agent and mupirocin as a topical agent, offer sufficient reliability for use against MSRA. Alternatives to glycopeptides and mupirocin rest with the development of new drugs from several classes of compounds. 相似文献
47.
R. Fingerhut W. Schmitz B. Garavaglia H. Reichmann E. Conzelmann 《Journal of inherited metabolic disease》1994,17(5):527-532
Summary Phytanic acid -oxidation was studied in cultures of skin fibroblasts and myoblasts from patients with various defects of the respiratory chain in order to obtain information on the subcellular site and the mechanism of this pathway. In fibroblasts from patients with complex IV (cytochromec oxidase) deficiency or glutaricaciduria type II, phytanic acid -oxidation was reduced to 14% of normal, whereas in myoblasts from patients with complex I (NADH-Q reductase) deficiency, it was normal. Apparently, at least one step of phytanic acid -oxidation occurs in mitochondria and in this process electrons are transferred to the respiratory chain via the electron-transfer flavoprotein (ETF). 相似文献
48.
Naujocks G Schmitz A Schramm J Wiestler O Schirrmacher V 《International journal of oncology》1995,6(4):759-765
Using two malignant rat glioma cell lines, we tested to what extent peripheral immunization could affect tumor growth in the brain of syngeneic rats. Peripheral subcutaneous (s.c.) immunization was performed with autologous Newcastle-disease-virus (NDV)-infected or non-infected live tumor cells. Thus immunized rats or non-immunized controls were intracerebrally implanted with increasing numbers of the respective malignant glioma cells. Without immunization the mean survival time after intracerebral implantation of 1x10(4) TZ363 or RG2 glioma cells was 9 and 29 days respectively. After s.c. immunization with either NDV-infected or non-infected TZ363 cells only 25% or less of challenged animals developed tumors in the brain. Immunization with NDV only had no effect. In RG2 glioma, s.c. immunization had no effect on tumor growth in the central nervous system and on survival time, no matter what kind of vaccine was used. These results clearly show, that in principle the efferent arm of the anti-tumor response can be effective accross the blood-brain barrier and extend into the microenvironment of the central nervous system. Whether or not glioma lines can induce this immunity and respond to it, seems to depend on their individual immunobiological characteristics. 相似文献
49.
Chronic motor neuropathies: response to interferon-beta1a after failure of conventional therapies 总被引:1,自引:0,他引:1 下载免费PDF全文
Martina IS van Doorn PA Schmitz PI Meulstee J van der Meché FG 《Journal of neurology, neurosurgery, and psychiatry》1999,66(2):197-201
OBJECTIVES: The effect of interferon-beta1a (INF-beta1a; Rebif) was studied in patients with chronic motor neuropathies not improving after conventional treatments such as immunoglobulins, steroids, cyclophosphamide or plasma exchange. METHODS: A prospective open study was performed with a duration of 6-12 months. Three patients with a multifocal motor neuropathy and one patient with a pure motor form of chronic inflammatory demyelinating polyneuropathy were enrolled. Three patients had anti-GM1 antibodies. Treatment consisted of subcutaneous injections of IBF-beta1a (6 MIU), three times a week. Primary outcome was assessed at the level of disability using the nine hole peg test, the 10 metres walking test, and the modified Rankin scale. Secondary outcome was measured at the impairment level using a slightly modified MRC sumscore. RESULTS: All patients showed a significant improvement on the modified MRC sumscore. The time required to walk 10 metres and to fulfil the nine hole peg test was also significantly reduced in the first 3 months in most patients. However, the translation of these results to functional improvement on the modified Rankin was only seen in two patients. There were no severe adverse events. Motor conduction blocks were partially restored in one patient only. Anti-GM1 antibody titres did not change. CONCLUSION: These findings indicate that severely affected patients with chronic motor neuropathies not responding to conventional therapies may improve when treated with INF-beta1a. From this study it is suggested that INF-beta1a should be administered in patients with chronic motor neuropathies for a period of up to 3 months before deciding to cease treatment. A controlled trial is necessary to confirm these findings. 相似文献
50.
The theoretical background of the present investigation was the decoupling hypothesis of alexithymia, which presumes for alexithymic individuals a dissociation of psychophysiological indicators of emotion from verbal cognitive awareness of one's emotional state. To study alterations in reactivity to emotionally distressing stimuli in alexithymic individuals, 12 high-alexithymic and 14 low-alexithymic subjects (separated by TAS) out of a general sample of 54 were investigated. All subjects were exposed to cognitive (CPT) and affect inductive (film sequences) distress. During stimulus exposition electrodermal activity (spontaneous fluctuations) was recorded. After stimulus exposition the subjects assessed their emotional reaction towards the film sequences (DAS). Concerning electrodermal activity no differences were found between high and low alexithymics under cognitive distress. In any case a significant autonomous arousal was registered. However, only the low alexithymic subjects but not the high alexithymics showed a significant increase of spontaneous fluctuations as expression of autonomous arousal during presentation of affect inductive stimuli. The altered psychophysiological reactivity found in high alexithymics in contrast to low alexithymic subjects was revealed specifically for the processing of emotional qualified stimuli. However, there was no difference between the groups in cognitive self assessment of emotional response towards the film sequences. The findings are discussed with reference to neurophysiological and psychodynamic models and the decoupling hypothesis of alexithymia. 相似文献