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991.
Folic Acid does not limit endothelial dysfunction induced by ischemia and reperfusion: a human study
Dragoni S Gori T Di Stolfo G Sicuro S Forconi S Parker JD 《Journal of cardiovascular pharmacology》2005,46(4):494-497
Nitric oxide synthase (NOS) uncoupling is a condition of increased production of superoxide anion associated with a decreased production of nitric oxide (NO) by this enzyme. Folic acid can prevent and/or reverse NOS uncoupling in the setting of diabetes, smoking, hypercholesterolemia, and nitrate tolerance. Whereas animal studies showed a protective effect of folic acid in ischemia and reperfusion (IR) injury, no study tested whether folic acid administration limits IR-induced endothelial dysfunction in humans. In a double-blind, parallel study, 20 healthy young male volunteers were randomized to receive folic acid, 10 mg/d for 7 days, or matching placebo. At the end of the treatment period, endothelium-dependent, flow-mediated dilation (FMD) of the radial artery was measured before and after IR injury (15 minutes of ischemia at the level of the brachial artery followed by 15 minutes of reperfusion). There was no difference at baseline between groups in any variable. In the placebo group, IR significantly blunted FMD (before IR, 6.7+/-1.0%; after IR, 1.5+/-1.3%, P<0.01). A similar effect was observed in the folic acid group (before IR, 6.3+/-1.1%; after IR, 2.1+/-1.0%, P=ns compared with placebo). As opposed to animal studies, high-dose folic acid does not protect the vascular endothelium from IR injury in humans. 相似文献
992.
A mutated p53 status did not prevent the induction of apoptosis by sulforaphane,a promising anti-cancer drug 总被引:2,自引:0,他引:2
Fimognari C Sangiorgi L Capponcelli S Nüsse M Fontanesi S Berti F Soddu S Cantelli-Forti G Hrelia P 《Investigational new drugs》2005,23(3):195-203
Summary We investigated apoptosis induction by sulforaphane on three cell lines characterized by a different p53 status. In particular, we used p53-knock-out fibroblasts from newborn mice transfected with the p53-Ser220 mutation, observed in Li-Fraumeni Syndrome patients, as a model of mutated p53 status. Moreover, immortalized fibroblasts from newborn mice expressing or lacking p53 (p53 +/+ andp53-/-, respectively) have been used to verify whether mutated p53 status could prevent sulforaphane-induced apoptotic events. Sulforaphane was able to induce apoptosis on all three cell lines. Indeed, the caspase-3 assays and poly(ADP-ribose)polymerase (PARP) cleavage data indicated that sulforaphane stimulated caspase-3-like activity and degradation of PARP. However, cells with a wild-type or mutated p53 appeared to be more sensitive to the effects of sulforaphane than cells lacking p53. Taken together, our results suggest that sulforaphane could act by a p53-independent pathway. For this reason, sulforaphane can be viewed as a novel agent useful not only in the treatment of Li-Fraumeni-associated tumors but also drug resistant tumors where p53 dysregulation is a feature. 相似文献
993.
Cassiani SH 《Revista brasileira de enfermagem》2005,58(1):95-99
Administering medication to patients is a complex process with various phases which contemplate a series of inter-related decisions and actions involving professionals from a number of disciplines as well as patients themselves. Errors may occur in any phase of such process. This article describes the indexes, terminology and classification of medication errors and determines the approaches which explain their occurrence, namely the person-centered approach and the system-centered approach. The aim of the paper was to contribute, through theoretical elements, to the strategic discussions concerning the improvement of care standards in health care institutions in our country, focusing on patient safety related to drug therapy. 相似文献
994.
995.
Lamioni A Parisi F Isacchi G Giorda E Di Cesare S Landolfo A Cenci F Bottazzo GF Carsetti R 《Transplantation》2005,79(7):846-850
Extracorporeal photopheresis (ECP) may represent an alternative to immunosuppression, as a means of reducing rejection after thoracic organ transplantation. The mechanism by which ECP exerts its protective effects has, until now, remained elusive. We analyzed peripheral blood mononuclear cells of four children with chronic heart and lung transplant rejection, who received ECP in addition to conventional immunosuppressive treatment. The effects of ECP were evaluated at each cycle, comparing blood samples from the same patient collected before and after treatment. In vitro, peripheral blood mononuclear cells treated with ECP undergo apoptosis and are phagocytosed by immature dendritic cells, which, in turn, acquire a tolerogenic phenotype. The frequency of T cells, with a regulatory phenotype and strong suppressive activity, was significantly increased in the blood of ECP-treated patients. The immunomodulatory effects of ECP may be explained by its ability to increase the frequency of regulatory T cells with inhibitory action on transplant immune rejection. 相似文献
996.
Mereuţă AI Poiati A Tuchiluş C Dorneanu O Nistor S Copăcianu B 《Revista medico-chirurgical?? a Societ????ii de Medici ??i Naturali??ti din Ia??i》2005,109(2):387-391
Modified Hodge test and a method using a disk with imipenem plus 1000 mg of EDTA were used to determine the presence of metallo-beta-lactamase producing gram-negative rods among 166 clinical isolates from hospitals in Ia?i and Gala?i. Of 9 imipenem resistant strains found, only one Pseudomonas aeruginosa gave positive results with both tests and other two P. aeruginosa clinical isolates gave negative results with both tests. The rest of the strains (2 P. aeruginosa, 2 Acinetobacter baumanii, 1 Sphingomonas paucimobilis) did not give conclusive results. These screening methods are useful, simple and accessible to clinical laboratories. PCR is needed to confirm the presence of metallo-beta-lactamase gene in bacteria and to determine the type of the enzymes. 相似文献
997.
Rudnic I Solomon S Mârţu S Ursache M 《Revista medico-chirurgical?? a Societ????ii de Medici ??i Naturali??ti din Ia??i》2005,109(1):170-173
The infections due to herpes viruses are widely spread, people being every day at high risk of contamination starting early age. The characteristic of the herpes virus infection consists of a symptom less evolution following the prime infection. As for any other herpetic infection, episodes infection exacerbation is due to some determining factors. Clinical symptom in herpes virus infection varies according to the virus type, age of the patient and site. Oral signs and symptoms are numerous, extremely intense and often, difficult to diagnose. Progressing in so many ways and being diagnosed and treated by so many medical specialties it is difficult to evaluate the actual number of cases. Consequently it is mandatory to train dentists in order to be able to accurately diagnose and treat the herpetic infection and to prevent nosocomial cross infections in dental office. 相似文献
998.
999.
Alvarez-Muñoz MT Zaragoza-Rodríguez S Rojas-Montes O Palacios-Saucedo G Vázquez-Rosales G Gómez-Delgado A Torres J Muñoz O 《Archives of medical research》2005,36(4):382-386
BACKGROUND: To measure HIV-1 RNA concentration requires venous extraction of blood, use of RNAase-free materials, and transport in a cold chain, which makes difficult the management of samples in developing countries. We evaluated the utility of the determination of HIV-1 RNA concentration in blood samples dried on filter paper (DBS) and subjected to different conditions, as contrasted with determination in plasma. METHODS: HIV-1 RNA concentration was determined in HIV-infected patients in DBS and in plasma samples. Samples were subjected to the following: DBS were stored at 4, 22, and 37 degrees C for 1, 3, and 7 days; samples from patients from four regions of Mexico were mailed to a reference laboratory; DBS were sent under environmental conditions; and plasma samples were sent frozen. HIV-1 RNA concentrations were determined by NucliSens in DBS and by Amplicor test in plasma. RESULTS: HIV-1 RNA concentration determined in DBS subjected to different temperatures and times had a significant correlation (r=0.99) with those obtained in plasma. When compared with values in plasma, Kappa agreement coefficients of values in DBS stored for 7 days at 4, 22, and 37 degrees C were 0.98, 0.83, and 0.94, respectively. Quantification of HIV-1 RNA in 108 DBS mailed from remote areas with different climates demonstrated significant correlation with those obtained in plasma (r=0.95; p <0.001). CONCLUSIONS: DBS is a simple and reliable method to measure HIV-1 RNA concentration, especially when samples are mailed from remote areas to a reference center. This collection method is an economic and suitable alternative for use in developing countries. 相似文献
1000.
Roznovanu SL Amălinci C Rădulescu D 《Revista medico-chirurgical?? a Societ????ii de Medici ??i Naturali??ti din Ia??i》2005,109(3):577-583
Prostate cancer is the most common malignancy in males. Despite the efforts for an early diagnosis, approximately one third of the cases are diagnosed in advanced clinical stages. Prostatic cancer, as the function of normal prostate is dependent upon androgens. So, androgenic deprivation represents an effective treatment especially in advanced cases. Although, the majority of patients will initially respond to androgen blockade, consequently the hormone-resistance will develop and the tumor will progress. The mechanism that determines tumoral progression during the endocrine treatment is driven by genomic instability, characterized by activating mutations of androgen receptor gene (AR), progression of some cellular clones possible of neuroendocrine origin that become adapted to low concentrations of residual adrenal androgens, suppression of apoptosis, by bcl-2 oncogene overexpression and p53 mutations, and growth factors (IGF-1--Insulin-like growth factor, KGF--keratinocyte growth factor, EGF--Epidermal growth factor, TGF a, b- Transforming growth factor a and b, bFGF--Fibroblastic growth factor type b) regulatory effect through either a paracrine or an autocrine mechanism. The identification of molecular alterations that appear during prostate carcinogenesis, may lead to the identification of new molecular targets to prevent hormone-resistance and to improve the prognosis in prostate cancers. 相似文献