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The antigenic sites on the major allergen from yellow mustard (Sinapis alba L.) seeds were studied using murine (BALB/c) monoclonal antibodies (mAb) and human IgE antibodies. Ten IgG1 (K) mAb from two fusions were analyzed. Competition and complementation studies performed with peroxidase labeled mAb reveal the existence of two main antigenic sites in Sin a I. All the described mAb failed to recognize the unordered carboxyamidomethylated polypeptide chains, with the single exception of 2B3, which binds the alkylated large chain. However, this mAB cannot react with the tetranitromethane-modified protein which retains the native conformation. This fact suggests that the only tyrosine of Sin a I, located in the large chain, may be part of a sequential epitope of the allergen. This chemical modification also alters the binding of the mAb 4A11 and 3F3 to the allergen, besides 2B3. The three mAb belong to the same complementation group. Specific IgE binding cannot be inhibited either by the large or small carboxyamidomethylated polypeptide chains, while the nitrated allergen shows a weaker inhibitory activity than the native Sin a I. 4A11, which is a tyrosine-dependent mAb, causes the greatest binding inhibition of the tested mAb on human IgE from atopic individuals, as determined from a reverse enzyme immunoassay, suggesting an important role played by tyrosine in the immunochemical recognition of Sin a I. 相似文献
13.
Danila Valmori Jackeline F. Romero Ying Men Janet L. Maryanski Pedro Romero Giampietro Corradin 《European journal of immunology》1994,24(6):1458-1462
We have previously demonstrated that it is possible to induce a consistent and strong cytolytic T lymphocyte (CTL) response to synthetic peptides, corresponding to poorly immunogenic malaria CTL epitopes, by co-injecting them with peptides representing defined T helper (Th) epitopes in incomplete Freund's adjuvant (IFA). In this study we have tested different immunization protocols to improve further the elicitation of the CTL response. We show that the CTL response to a mixture of Th + CTL peptides administered in IFA was further enhanced by a previous injection of the Th epitope peptide in IFA. Moreover, we found that the response could be significantly augmented by a pre-injection of IFA alone. This enhancement was observed only if the Th epitope was also present in the second injection. The number of lymph node cells recovered was 2–3-fold higher in mice pre-injected with IFA, but the increase in specific CTL activity, expressed as lytic units per animal, by pre-injection of IFA was at least 10–20-fold. Thus, pre-injection of IFA clearly increases the magnitude of a subsequent CTL response. 相似文献
14.
Crombet T Torres O Rodríguez V Menéndez A Stevenson A Ramos M Torres F Figueredo R Veitía I Iznaga N Pérez R Lage A 《Hybridoma》2001,20(2):131-136
High levels of growth factors and their receptors have been demonstrated in human tumors. Gliomas and meningiomas are characterized by overexpression of epidermal growth factor receptor (EGF-R). Ior egf/r3, is a neutralizing murine monoclonal antibody (MAb) against EGF-R, and was generated at the Cuban Institute of Oncology. The antibody recognizes EGF-R with high affinity, inhibiting tyrosine kinase activation. A clinical trial was conducted in brain tumor patients to evaluate toxicity, immunogenicity, and clinical benefit of escalating doses of the antibody. Nine patients with histologically confirmed gliomas or meningiomas, who had active or recurrent disease after receiving conventional treatment, received four intravenous doses of ior egf/r3. Total dosages ranged from 160 to 480 mg. As inclusion criteria, radioimmunoscintigraphy with the same MAb labeled with 99mTechnetium (99mTc) was performed. Immune response against the murine antibody was also evaluated. After four doses of ior egf/r3 MAb, no significant toxicity was found, except in one patient who developed a grade 4 allergic adverse event. This reaction was probably related with previous sensitization to the same MAb and the development of human anti-mouse antibodies (HAMA) response. Despite no major objective antitumor responses, eight patients had stable disease on the 6-month evaluation, and two patients remain alive after four years of MAb therapy. 相似文献
15.
N Menéndez O Herreras J M Solis A S Herranz R Martín del Río 《Neuroscience letters》1989,102(1):64-69
Taurine increases in brain extracellular space due to glutamate agonists were studied in vivo in the rat hippocampus using a dialysis technique, both in the absence and in the presence of glutamate receptor antagonists. Extracellular taurine levels increased during perfusions of agonists, listed in descending order of potency: kainate (KA), N-methyl-D-aspartate (NMDA), and quisqualate (QA). While taurine increases due to KA or QA perfusions were inhibited by 6,7-dinitro-quinoxaline-2,3-dione (DNQX), those induced by NMDA were abolished in the presence of 3-(carboxypiperazin-4-yl)-propyl-1-phosphonic acid (CPP). These results indicate that increases in extracellular taurine levels evoked by NMDA, KA or QA in the rat hippocampus are caused by activation of their specific receptors. Field potentials, concomitantly recorded, were quickly abolished during NMDA or KA perfusions (0.1 mM), while QA (0.25 mM) induced the appearance of bicuculline-like evoked responses. Since taurine has been proposed as an osmoregulatory substance in the rat brain, and cell swelling is known to be an early component of glutamate agonists neurotoxicity, the increases in extracellular taurine reported here could be due to taurine released through an osmoregulatory process, counteracting the neurotoxic cellular oedema induced by glutamate agonists. 相似文献
16.
Alonso J Frayle H Menéndez I López A García-Miguel P Abelairas J Sarret E Vendrell MT Navajas A Artigas M Indiano JM Carbone A Torrenteras C Palacios I Pestaña A 《Human mutation》2005,25(1):99
Constitutional mutations in the RB1 gene predispose to retinoblastoma development. Hence genetic screening of retinoblastoma patients and relatives is important for genetic counseling purposes. In addition, RB1 gene mutation studies may help decipher the molecular mechanisms leading to tumors with different degrees of penetrance or expressivity. In the course of genetically screening of 107 hereditary and non-hereditary retinoblastoma patients (11 familiar bilateral, 4 familiar unilateral, 49 sporadic bilateral and 43 sporadic unilateral) and kindred from Spain, Colombia and Cuba, using direct PCR sequencing, we observed 45 distinct mutations and four RB1 deletions in 53 patients (9 familiar bilateral, 2 familiar unilateral, 31 sporadic bilateral and 11 sporadic unilateral). Most of these mutations (26/45, 57%) have not been reported before. In 32 patients, the predisposing mutations correspond to nonsense (mainly CpG transitions) and small insertions or deletions whose expected outcome is a truncated Rb protein that lacks the functional pockets and tail. Five single aminoacid replacements and seventeen mutations affecting splicing sites were also observed in retinoblastoma patients. Two of these sixteen mutations are of unclear pathogenic nature. 相似文献
17.
BACKGROUND: This study was conducted on human cervical mucus using light microscopy (LM) and scanning electron microscopy (SEM). The objective was the morphological characterization of the different mucus types, with samples taken from the lumen of the cervix and from the different secretory zones of the cervical mucosa. METHODS: A total of 230 samples from 195 women were spread out on slides and air dried. The phenomenon of 'ferning' was observed and assessed in these samples using both LM and SEM. Further samples from the lumen of the cervix and the different secretory crypts were spread out on cover slips and fixed with glutaraldehyde (2.5%) to be studied by SEM. RESULTS: The results show the presence of four different morphological mucus types, namely L, S, P and G, in both types of sample using dried and fixed techniques. CONCLUSIONS: Mucus from the lumen of the cervix appears to be a morphologically heterogeneous entity. It contains different types of secretions, the proportions of which vary throughout the menstrual cycle. The different mucosal types show different types of crystallization, different patterns of ultrastructure (probably related to the arrangement of the glycoprotein network) and are produced in different secretory zones of the crypts in the cervix. 相似文献
18.
M.A. Pajares J.A. Margarit C. García-Camacho J. García-Suarez E. Mateo M. Castaño C. López Forte J. López Menéndez M. Gómez M.J. Soto S. Veiras E. Martín B. Castaño S. López Palanca T. Gabaldón J. Acosta J. Fernández Cruz A.R. Fernández López R. Vicente 《Revista espa?ola de anestesiología y reanimación》2021,68(4):183-231
The ERAS guidelines are intended to identify, disseminate and promote the implementation of the best, scientific evidence-based actions to decrease variability in clinical practice. The implementation of these practices in the global clinical process will promote better outcomes and the shortening of hospital and critical care unit stays, thereby resulting in a reduction in costs and in greater efficiency. After completing a systematic review at each of the points of the perioperative process in cardiac surgery, recommendations have been developed based on the best scientific evidence currently available with the consensus of the scientific societies involved. 相似文献
19.
健脑安治疗血管性痴呆肾虚痰浊证的单盲对照研究 总被引:2,自引:0,他引:2
目的 评价健脑安治疗血管性痴呆肾虚痰浊证的临床疗效,论证补肾降浊法是否为治疗血管性痴呆的一种有效疗法。方法 6周随机单盲对照临床试验。40例轻中度VD病人,治疗组25例,对照组15例。治疗组给予口服复方中药制剂健脑安片,1片/次,3次/d。对照组给予口服都可喜片,40mg/次,2次/d。结果 健脑安能显改善血管性痴呆肾虚痰浊证,并且其改善肾虚痰浊证的疗效显优于都可喜(P<0.05)。结论 健脑安对血管性痴呆患肾虚痰浊证的疗效显优于都可喜。补肾降浊法为治疗血管性痴呆的有效治法,具有指导临床治疗痴呆用药和进一步临床研究的价值。 相似文献
20.
Fariña Pérez LA Menéndez P Astudillo A González del Rey C Manjón JA Medina AG 《Actas urologicas espa?olas》1999,23(10):885-887
Urinary infection due to urea splitting bacteria leads to a rise in urinary pH, favouring the precipitation of calcium salts and struvita crystals. If deposited on the surface of a bladder with chronic inflammation or some other previous lesion, may produce an alkaline encrusted cystitis, now a rare condition. In the case here presented, occurred in a 69-year-old male. Corynebacterium urealyticum grown in the urine, and some foci of malakoplakia were found in the area of encrustation endoscopically excised. This case seems to be the third example of alkaline encrusted cystitis associated with malakoplakia reported in the bibliography. These two conditions share similar clinical signs and may probably have a common aetiopathogenesis. 相似文献