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991.
Raquel Chacon Ruiz Martinez Amanda Ribeiro de Oliveira Marcus Lira Brand?o 《European neuropsychopharmacology》2007,17(11):717-724
The amygdala is an important filter for unconditioned and conditioned aversive information. The amygdala synthesizes the stimuli input from the environment and then signals the degree of threat that they represent to the dorsal periaqueductal gray (dPAG), which would be in charge of selecting, organizing and executing the appropriate defense reaction. In this study, we examined the influence of fluoxetine microinjections (1.75 and 3.5 nmol/0.2 microL) into the lateral (LaA) and basolateral (BLA) amygdaloid nuclei on the freezing and escape responses induced by electrical stimulation of the dPAG. Freezing behavior was also measured after the interruption of the electrical stimulation of the dPAG. On the following day, these rats were also submitted to a contextual fear paradigm to examine whether these microinjections would affect the conditioned freezing to contextual cues previously associated with foot shocks. Fluoxetine injections into both amygdaloid nuclei did not change the freezing and escape thresholds, but disrupted the dPAG-post-stimulation freezing. Moreover, the conditioned freezing was enhanced by fluoxetine. Whereas 5-HT mechanisms in the amygdala facilitate the acquisition of conditioned fear they inhibit the dPAG-post-stimulation freezing. However, the unconditioned fear triggered by activation of the dPAG is produced downstream of the amygdala. These findings have important implications for the understanding of the neurochemical substrates that underlie panic and generalized anxiety disorders. 相似文献
992.
993.
Roger L Milne Ana Osorio Teresa Ramón Y Cajal Ana Vega Gemma Llort Miguel de la Hoya Orland Díez M Carmen Alonso Conxi Lazaro Ignacio Blanco Ana Sánchez-de-Abajo Trinidad Caldés Ana Blanco Bego?a Gra?a Mercedes Durán Eladio Velasco Isabel Chirivella Eva Esteban Carde?osa María-Isabel Tejada Elena Beristain María-Dolores Miramar María-Teresa Calvo Eduardo Martínez Carmen Guillén Raquel Salazar Carlos San Román Antonis C Antoniou Miguel Urioste Javier Benítez 《Clinical cancer research》2008,14(9):2861-2869
PURPOSE: It is not clear that the published estimates of the breast and ovarian cancer penetrances of mutations in BRCA1 and BRCA2 can be used in genetic counseling in countries such as Spain, where the incidence of breast cancer in the general population is considerably lower, the prevalence of BRCA2 mutations seems to be higher, and a distinct spectrum of recurrent mutations exists for both genes. We aimed to estimate these penetrances for women attending genetic counseling units in Spain. EXPERIMENTAL DESIGN: We collected phenotype and genotype data on 155 BRCA1 and 164 BRCA2 mutation carrier families from 12 centers across the country. Average age-specific cumulative risks of breast cancer and ovarian cancer were estimated using a modified segregation analysis method. RESULTS: The estimated average cumulative risk of breast cancer to age 70 years was estimated to be 52% [95% confidence interval (95% CI), 26-69%] for BRCA1 mutation carriers and 47% (95% CI, 29-60%) for BRCA2 mutation carriers. The corresponding estimates for ovarian cancer were 22% (95% CI, 0-40%) and 18% (95% CI, 0-35%), respectively. There was some evidence (two-sided P = 0.09) that 330A>G (R71G) in BRCA1 may have lower breast cancer penetrance. CONCLUSIONS: These results are consistent with those from a recent meta-analysis of practically all previous penetrance studies, suggesting that women with BRCA1 and BRCA2 mutations attending genetic counseling services in Spain have similar risks of breast and ovarian cancer to those published for other Caucasian populations. Carriers should be fully informed of their mutation- and age-specific risks to make appropriate decisions regarding prophylactic interventions such as oophorectomy. 相似文献
994.
Cátia Moutinho Ana R Mateus Fernanda Milanezi Fátima Carneiro Raquel Seruca Gianpaolo Suriano 《BMC cancer》2008,8(1):10
Background
EGFR overexpression has been described in many human tumours including gastric cancer. In NSCLC patients somatic EGFR mutations, within the kinase domain of the protein, as well as gene amplification were associated with a good clinical response to EGFR inhibitors. In gastric tumours data concerning structural alterations of EGFR remains controversial. Given its possible therapeutic relevance, we aimed to determine the frequency and type of structural alterations of the EGFR gene in a series of primary gastric carcinomas. 相似文献995.
Andrés Jesús Muñoz Martín Virginia Martínez Marín Juan Luis Arranz Cózar Luis Cabezón Gutiérrez Ricardo González del Val Subirats Pilar García Alfonso 《Clinical & translational oncology》2008,10(3):182-184
There is no standard chemotherapy regimen in advanced gastric cancer with poor performance status and hepatic dysfunction.
New chemotherapeutical agents and targeted therapy have demonstrated promising results in terms of efficacy and safety in
phase II clinical trials. We report the case of a 68-year-old man with stage IV gastric cancer and severe hepatic dysfunction
due to liver metastases treated with a combination of oxaliplatin, 5-fluorouracil and cetuximab. 相似文献
996.
Perea García J Lago Oliver J Muñoz Jiménez F del Valle E Duque Pérez C Turégano Fuentes F 《Gastroenterologia y hepatologia》2000,23(6):287-289
Portal hypertension frequently causes the appearance of porto-systemic shunts, such as esophageal varices and also, but with much less frequency, other atypical shunts known as ectopic varices. Despite their infrequency/rarity, ectopic varices can cause serious gastrointestinal bleeding. Intraabdominal adhesions, especially post-operative ones, promote their appearance. The therapeutic management of ectopic varices is initially the same as that for esophageal varices but surgical treatment is usually necessary as a diagnostic and therapeutic procedure. 相似文献
997.
998.
de la Puente-Redondo VA García del Blanco N Pérez-Martínez C González-Rodríguez MC Rodríguez-Ferri EF Gutiérrez-Martín CB 《Journal of comparative pathology》2000,122(2-3):217-222
Actinobacillus seminis isolates were cultured from the semen (two isolates) and the left testis (one isolate) of two one-year-old rams in León, Spain. One animal showed lesions of chronic unilateral orchitis and epididymitis while the other appeared to suffer a subclinical infection and only a moderate number of pleomorphic rods and inflammatory cells were present in its semen. The isolates were biochemically similar to the A. seminis type strain NCTC 10851 and two other European A. seminis isolates, except that they produced acid from sorbitol; their identity was confirmed by arbitrarily primed polymerase chain reaction. The isolates were also tested against 30 antimicrobial agents, and only marbofloxacin was found active against all of them. As far as is known, this is the first report of A. seminis isolation from rams in southern Europe. 相似文献
999.
Langerhans cells (LCs) are specialized dendritic cells (DCs) strategically located in stratified epithelia, such as those of the skin, oral cavity, pharynx, esophagus, upper airways, urethra, and female reproductive tract, which are exposed to a wide variety of microbial pathogens. LCs play an essential role in the induction of T-lymphocyte responses against viruses, bacteria, and parasites that gain access to those epithelial surfaces, due to their high antigen capture and processing potential and their capacity to present antigen peptides to T cells on migration to the lymph nodes.(1) Although LCs have been classically considered of myeloid origin, recent reports, which demonstrate the existence of lymphoid DCs derived from multipotent lymphoid precursors devoid of myeloid differentiation potential,(2-5) raise the question of the lymphoid or myeloid origin of LCs. The present study shows that mouse lymphoid-committed CD4(low) precursors, with the capacity to generate T cells, B cells, CD8(+) lymphoid DCs, and natural killer cells,(26) also generate epidermal LCs on intravenous transfer, supporting the view that LCs belong to the lymphoid lineage. (Blood. 2000;96:1633-1637) 相似文献
1000.