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51.
De Vos A Sermon K De Rijcke M Goossens V Henderix P Van Ranst N Platteau P Lissens W Devroey P Van Steirteghem A Liebaers I 《Molecular human reproduction》2003,9(7):429-435
Charcot-Marie-Tooth (CMT) disease is the 'common' name for a range of hereditary peripheral neuropathies. CMT1 is the most common form and is transmitted in an autosomal dominant manner. CMT1A maps to chromosome 17p11.2 and is caused, in the majority of cases, by a 1.5 Mb DNA duplication, that includes the peripheral myelin protein 22 (PMP) gene. This paper reports on preimplantation genetic diagnosis (PGD) for CMT1A in five couples. The CMT1A duplication was detected by fluorescent PCR analysis using polymorphic (CA)n markers localized within the duplication. Single-cell PCR on blastomeres allowed genetic analysis of embryos obtained after ICSI. Only healthy unaffected embryos were transferred to the uterus. PCR experiments with single EBV-transformed lymphoblasts or with research blastomeres allowed the evaluation of amplification efficiencies, as well as contamination and allele drop-out (ADO) rates for each PCR protocol. Three simplex PCR protocols (using one primer pair) and two duplex PCR protocols (using two primer pairs) were developed for CMT1A. Additionally, a protocol using all three primer pairs in triplex was also established. Thirteen clinical ICSI-PGD cycles were performed for five couples (12 simplex PCR cycles and one duplex PCR cycle), resulting in seven embryo transfers. Three singleton pregnancies ensued in two couples and three healthy babies were delivered. This report describes different fluorescent PCR-based tests which allow efficient and accurate single-cell level detection of the CMT1A duplication. On the basis of the presence of the healthy allele of the affected parent-to-be (and/or absence of the affected one), healthy embryos can be selected for transfer. The assays are suitable for PGD for other couples who present with the same CMT1A duplication [depending on their informativity for the (CA)n markers available] as described here. 相似文献
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T. M. de Reijke P. C. N. Vos E. C. de Boer R. F. M. Bevers W. H. de Muinck Keizer K. H. Kurth D. H. J. Schamhart 《Urological research》1993,21(5):349-352
Summary The study was initiated as an in vitro approach to the situation existing during intravesical bacillus Calmette-Guerin (BCG) instillation in patients with superficial bladder cancer. Cytokine secretion of a human bladder carcinoma cell line T24 treated with BCG was investigated. A 24-h treatment of T24 cells with BCG resulted in a tenfold higher secretion of interleukin-6 (IL-6) and tumor necrosis factor alpha (TNF) when compared with T24 cells treated with Escherichia coli, Streptococcus faecalis or a cell wall preparation of Nocardia rubra (N-CWS). No secretion of IL-1 and IL-2 was detected. Pre-exposing T24 cells to BCG for various periods of time indicated that a minimum exposure time of 0.5–1 h was required to upregulate IL-6 and TNF production. Extending the BCG pre-exposure time to 2 and 3 h further increased the rate of cytokine production. No significant difference was found, however, between the rate of secretion initiated after a 2-h or 3-h pre-exposure period. The amounts of these cytokines secreted in the presence of BCG-conditioned medium did not differ significantly from the constitutively secreted amounts, excluding an effect of products possibly secreted by BCG on the upregulation of IL-6 and TNF. In addition, upregulation of cytokine production appeared to be dependent on the concentration of BCG. The results suggest that cytokines may be produced by urothelial tumor cells after intravesical instillation in patients with superficial bladder cancer, which may play a role in the mode of action of BCG. 相似文献
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Visual interpolation between dots responsible for rectilinear versus curvilinear contour interpretation was examined with the psychophysical forced directional response (FDR) paradigm. Regular four-dot polygon segments, together with a target dot, were presented to the subjects for 150 ms. Subjects were required to indicate the direction of deviation of the target dot from the midpoint of the intermediate line segment. Crucial variables were the outer angle of the line segments and symmetry axis orientation of the polygon segment. Logistic regression analyses showed that curvilinear interpolation occurred for angles up to 30 degrees, but emerged more pervasively under the vertical symmetry axis orientation for angles up to 60 degrees. 相似文献
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Verduyn SC Vos MA Leunissen HD van Opstal JM Wellens HJ 《Journal of cardiovascular pharmacology》1999,33(2):212-222
In the anesthetized dog with complete chronic AV block (CAVB), we evaluated and compared the acute electrophysiologic effects of dronedarone i.v. (Dron, 2 times 2.5 mg/kg/10 min) and amiodarone i.v. (Amio, 2 times 5 mg/kg/10 min). This canine model with a high sensitivity for acquired torsade de pointes (TdP) provides an ideal substrate to evaluate ventricular repolarization abnormalities. Six ECG leads and two endocardial monophasic action potential (MAP) recordings in the left and right ventricle (LV and RV) were simultaneously recorded to measure QT time, action-potential duration (APD), interventricular dispersion (deltaAPD = LV(APD) - RV(APD)), early afterdepolarizations (EADs), ectopic beats (EBs), and TdP. Measurements were made at the spontaneous idioventricular rhythm (IVR) and 1,000-ms steady-state pacing. To investigate its short-term, antiarrhythmic properties, Dron was given after almokalant (0.12 mg/kg)-induced TdP. Furthermore, in another set of experiments, oral Dron (20 mg/kg, b.i.d) was given for 3 weeks to conscious CAVB dogs. Dron, i.v., shortened ventricular repolarization (QT, 435 +/- 60 to 360 +/- 55; LV(APD) 395 +/- 75 to 335 +/- 60 ms; p < 0.05), whereas IVR and ventricular effective refractory period (VERP, 225 +/- 30 to 230 +/- 30 ms) remained similar. Therefore the VERP/QT ratio increased (0.55 +/- 0.04 to 0.61 +/- 0.03; p < 0.05). Similar results were obtained with Amio, i.v.. Almokalant-induced TdP was characterized by an increased repolarization duration, deltaAPD, and EADs. Dron, i.v., suppressed the EADs, EBs, and TdP by a reduction and homogenization of repolarization (LV(APD), 505 +/- 110 to 455 +/- 80 ms, and deltaAPD, 110 +/- 55 to 65 +/- 40 ms). Long-term oral Dron increased the PP interval, CL-IVR, and QT(c) time. In contrast to oral treatment, Dron i.v. shortens ventricular repolarization parameters, resulting in suppression of EAD-dependent acquired TdP. The increased VERP/QT ratio after Dron i.v. may indicate an important second antiarrhythmic property. 相似文献
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The effects on social recognition memory of (Arg(8))-vasopressin (AVP-(1-9), [pGlu(4), Cyt(6)]AVP-(4-8) and oxytocin locally administered into the rat's septum were investigated. In the behavioural paradigm used, a juvenile intruder was presented to an adult resident male rat twice for 5 min, with an inter-exposure interval of 120 min. Peptide-free residents investigated the juvenile during the second encounter as long as during the first encounter. Intraseptal injection just after the first encounter with graded doses of (Arg(8))-vasopressin, [pGlu(4),Cyt(6)]AVP-(4-8) or oxytocin caused a decrease of social investigation, as compared to placebo treatment, indicating facilitation of social recognition. The least effective dose was 100pg, 200pg and 300pg respectively. The action of vasopressin was blocked by both d(CH(2))(5)[Tyr(Me)(2)]AVP and d(CH(2))(5)[D-Ile(2)Ile(4)]AVP, V(1) and V(2) vasopressinergic receptor antagonists, but not by desGly(NH(2))(9)-d(CH(2))(5)[Tyr(Me)(2)Thr(4)]-OVT, an oxytocinergic receptor antagonist. None of the antagonists blocked the oxytocin-facilitating action on social recognition. They also did not affect social recognition when injected alone. The effects of vasopressin seem to be mediated by vasopressinergic receptors dissimilar to those found in the periphery, while the receptors involved in the action of oxytocin remain to be elucidated. 相似文献
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Rommers GM Vos LD Klein L Groothoff JW Eisma WH 《Prosthetics and orthotics international》2000,24(1):28-38
There is little published material in recent years about the use of lower limb prostheses in an elderly amputee population. In this study the authors were interested in the technical changes to lower limb prostheses after a first limb fitting procedure in a post-rehabilitation population in The Netherlands. The process of fitting a prosthesis and the technical changes to the artificial limb in the first year afterwards are studied. 相似文献