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991.
Gomes MT Mello VJ Rodrigues KC Bemquerer MP Lopes MT Faça VM Salas CE 《Planta medica》2005,71(3):244-248
In a prior study we showed evidence that latex from Carica candamarcensis contains a protein fraction that stimulates mammalian cell proliferation. In this report we describe the isolation of two proteinases responsible for this effect. Both proteinases (P1, P2) display a relative mass of 23 kDa and following chromatographic purification stimulate proliferation of fibroblastic and epithelial cells. P2 added to L929 fibroblasts at 2.5 nM enhances proliferation by 60 %. We further demonstrate that its cellular effect is linked to an increase in activity of Erk2, a component of the MAP kinase pathway. To our knowledge, this is the first known plant proteinase to exert a proliferative effect in mammalian cells. This novel mitogenic property attributed to a purified cysteine proteinase may explain some of the therapeutic actions attributed to these enzymes. 相似文献
992.
Rationale It has been reported that 5-HT1A receptors modulate learning and memory and diverse pharmacological and genetic evidence supports this notion. Nevertheless,
there are few works about expression of these receptors during memory formation.
Objective We aimed to determine 5-HT1A receptor expression in brain areas of untrained, passive, and autoshaping trained groups of rats.
Methods Ex vivo receptor autoradiography using the ligand agonist [3H]8-hydroxy-2-[di-n-propylamino]tetralin] (8-OH-DPAT) was used.
Results The trained group relative to untrained animals showed increases of 5-HT1A receptor expression in 14 brain areas, decrements in 7, and no changes in 12. Thus, in contrast to untrained rats, 5-HT1A receptor expression of autoshaping trained rats was augmented in the tubercule olfactory, septal nucleus, nucleus accumbens,
caudate putamen, globus pallidus, striate, and parietal (1 and 2), temporal cortex (1 and 3), granular retrosplenial cortex
(1), amygdala, and median and dorsal raphe nuclei. In contrast, in the latter group, receptors were decreased in the CA1 area,
hypothalamus dorsal, frontal cortex (1 and 3), occipital cortex, cingulate cortex (1 and 2), and cuneiform nucleus. There
were significant differences between passive vs trained groups, but not regarding untrained rats, in the lateral olfactory
tract, dentate gyrus, CA3 area, ventromedial hypothalamic, lateral hypothalamus, preoptic medial, frontal cortex (2), granular
retrosplenial cortex (2), entorhinal cortex (1 and 2), piriform cortex, and substantia nigra.
Conclusions These data suggest that upregulated, downregulated, and “silence” of 5-HT1A receptors in brain areas form part of neural circuits engaged in memory formation by demonstrating a high degree of specificity
and memory mapping. 相似文献
993.
Skubis-Zegadło J Nikodemska A Przytuła E Mikula M Bardadin K Ostrowski J Wenzel BE Czarnocka B 《British journal of cancer》2005,93(1):144-151
The Pendred syndrome gene (PDS) encodes a transmembrane protein, pendrin, which is expressed in follicular thyroid cells and participates in the apical iodide transport. Pendrin expression has been studied in various thyroid neoplasms by means of immunohistochemistry (IHC), Western blot and RT-quantitative real-time PCR. The expression was related to the functional activity of the thyroid tissue. Follicular cells of normal, nodular goitre and Graves' disease tissues express pendrin at the apical pole of the thyrocytes. In follicular adenomas, pendrin was detected in cell membranes and cytoplasm simultaneously in 10 out of 15 cases. Pendrin protein was detected in 73.3 and 76.7% of the follicular (FTC) and papillary (PTC) thyroid carcinomas, respectively, where pendrin was solely localised inside the cytoplasm. An extensive intracellular immunostaining of pendrin was observed in six out of 11 (54.5%) of positive FTCs and 19 out of 23 (82%) of PTCs. Focal reactivity was detected in one follicular- and three papillary carcinomas, whereas pendrin protein was absent in three of 15 FTC and four of 30 PTC; mRNA of pendrin was detected in 92.4% of thyroid tumours. The relative mRNA expression of pendrin was lower in cancers than in normal thyroid tissues (P<0.001). The pendrin protein level was found to parallel its mRNA expression, which was not, however, related to the tumour size and tumour stage. In conclusion, pendrin is expressed in the majority of differentiated thyroid tumours with high individual variability but its targeting to the apical cell membrane is affected. 相似文献
994.
Detection of JC virus DNA sequences and expression of viral T antigen and agnoprotein in esophageal carcinoma 总被引:4,自引:0,他引:4
Del Valle L White MK Enam S Piña Oviedo S Bromer MQ Thomas RM Parkman HP Khalili K 《Cancer》2005,103(3):516-527
BACKGROUND: The human polyomavirus JC virus (JCV) causes progressive multifocal leukoencephalopathy. Subclinical infection with JCV occurs in 85-90% of the population worldwide. The virus usually remains latent but can reactivate under immunosuppressive conditions, resulting in progressive multifocal leukoencephalopathy. JCV is oncogenic in experimental animals and is associated with human brain tumors. JCV is found in normal mucosa of the gastrointestinal tract, and some colon carcinomas express the oncogenic JCV T-antigen protein. The objective of this study was to examine the presence of JCV DNA sequences and JCV protein expression in normal and malignant human esophageal tissues. METHODS: The authors examined the presence of JCV DNA sequences and protein expression in normal and malignant human esophageal tissues. Seventy well characterized biopsy specimens from patients with a spectrum of esophageal disorders were studied by immunohistochemistry, and 18 specimens were analyzed further by polymerase chain reaction amplification. RESULTS: JC viral DNA was isolated from 11 of 13 normal esophageal biopsy specimens (85%) and from 5 of 5 esophageal carcinomas (100%). Using immunohistochemistry, JCV T antigen was detected in 10 of 19 carcinomas (53%), agnoprotein was detected in 8 carcinomas (42%), p53 tumor suppressor was detected in 11 carcinomas (58%), and beta-catenin was detected in 4 carcinomas (21%). Zero of 51 normal, benign, and premalignant esophageal samples expressed viral proteins. Laser-capture microdissection verified the presence and specificity of JCV DNA sequences. beta-Catenin and p53 were colocalized with JCV T-antigen in the nuclei of neoplastic cells. CONCLUSIONS: The results provide evidence for infection of gastrointestinal tract cells by JCV and suggest a potential role of JCV in the development of upper digestive tract carcinomas. 相似文献
995.
Following two years of low influenza incidence in Poland, the activity of this disease markedly increased in 2003. In total 1,216,285 cases of influenza like illness were registered (incidence 3,184.4 per 100,000). Regionally the incidence ranged from 1,195.7 in Zachodniopomorskie to 5,719.7 per 100,000 in Mazowieckie. Children and adolescents under 15 years of age accounted for 41.7% of all cases (507,102 cases, age specific incidence 7,579.0 per 100,000). In this age group the incidence varied regionally from 2,718.1 in Podlaskie to 14,087.6 per 100,000 in Mazowieckie. 3,128 patients (0.26% of all cases) required hospital admission. There were 141 deaths due to influenza (mortality 0.12%) in 2003, in 78.7% these were persons over 70 years of age. Nineteen strains of influenza virus were isolated in 2003 in Poland, including 15 strains of subtype A(H3), 3 strains of subtype A(H1) and one strain of type B. Besides, in other 10 cases influenza A infection was confirmed by direct immunofluorescence test. All isolated influenza strains were antigenically similar to the vaccine strains recommended for the epidemic season 2002/03 and 2003/04. 相似文献
996.
OBJECTIVE: To analyze the infant mortality trend in a metropolitan area, from 1984 to 1998. The main focus was on avoidable causes of neonatal and post-neonatal mortality. METHODS: Sources of data were the Sistema de Informacoes em Mortalidade do Ministerio da Saude (SIM-MS) [Mortality Information System of the Ministry of Health] and Fundacao Instituto Brasileiro de Geografia e Estatistica (IBGE) [Brazilian Institute of Geography and Statistics Foundation] (official live birth and death records) for the metropolitan region of Belo Horizonte, in the State of Minas Gerais. A simple linear regression model was used to evaluate time-trends of mortality rates. Statistical significance of the inclination of the regression curves was considered for the p<0.05 level. RESULTS: During the 15 year period in question, the infant mortality rate declined from 48.5 to 22.1/1,000 live births. However, the most accentuated decrease was observed during the last four years of the study period. The post-neonatal group was greatly responsible for this decline both in the capital and in the other districts within the metropolitan region of Belo Horizonte. CONCLUSIONS: Although a significant decrease in the infant mortality rate has been observed, particularly in the post-neonatal mortality, it is still larger than the rates found in developed countries. Deaths due to perinatal morbidities as well as the group of causes represented by diarrhea-pneumonia-malnutrition still present an important potential for reduction. The authors discuss the role of the health services in improving the rates of these avoidable causes of infant mortality. 相似文献
997.
OBJECTIVE: To assess the relationship between engaging in high-risk sexual practices for HIV infection and the internalized oppression of homo and bisexual males due to the prejudice and discrimination they face. METHODS: An observational cross-sectional study was carried out between September and November 2001. A questionnaire was applied to 318 males who sought services and institutions in Mexico City. The studied variables were: internalized homophobia, perception of stigma, concealing sexual orientation, and sexual practices in the six months prior to the survey. The relationship (odds ratios) between forms of internalized oppression with high-risk sexual practices was estimated using logistic regression models adjusted for confounders. RESULTS: Of all respondents, 256 reported having had at least one sexual relationship in the last six months, 50 reported having none, and 12 did not answer this question. More than 30% had not used condoms when they engaged in insertive or receptive anal sex. Internalized homophobia was associated with higher risk of drug consumption before or during sexual encounters, unprotected insertive/receptive anal sex, and swallowing semen from other men. CONCLUSIONS: Engaging in high-risk sexual practices is still frequent among homo and bisexual males. Of the three forms of internalized oppression studied, homophobia was associated with higher high-risk sexual practices. This information may be incorporated into the design of programs for promoting condom use among homo and bisexual males. 相似文献
998.
999.
León FR Brambila C de la Cruz M García Colindres J Morales C Vásquez B 《Studies in family planning》2005,36(2):117-126
The balanced counseling strategy developed in Peru improved family planning care and clients' knowledge of their contraceptive method choice, but few providers adopted it. To expand its use, an algorithm was introduced and training, job aids, and reinforcement were supplied to Ministry of Health providers, most of whom were paraprofessionals, from two areas (40 clinics) in Guatemala. Mystery clients made pretest and post-test visits to these clinics and to providers from a nonequivalent control group (40 clinics). The results showed that the strategy was used in 85 percent of the controlled consultations at the experimental clinics. Use of the strategy improved quality of care regardless of the provider's performance at baseline and regardless of ethnic or regional differences. Counseling session length increased by nine minutes, but real-client load did not change. Guatemalan clients can be expected to benefit from the strategy. The increased session length has not yet caused problems, but it may pose policy dilemmas in the future. 相似文献
1000.
Lewis LB Sloane DC Nascimento LM Diamant AL Guinyard JJ Yancey AK Flynn G;REACH Coalition of the African Americans Building a Legacy of Health Project 《American journal of public health》2005,95(4):668-673
OBJECTIVES: We examined availability and food options at restaurants in less affluent (target area) and more affluent (comparison area) areas of Los Angeles County to compare residents' access to healthy meals prepared and purchased away from home. We also considered environmental prompts that encourage the purchase of various foods. METHODS: We designed an instrument to assess the availability, quality, and preparation of food in restaurants. We also assessed advertisements and promotions, cleanliness, and service for each restaurant. We assessed 659 restaurants: 348 in the target area and 311 in the comparison area. RESULTS: The nutritional resource environment in our target area makes it challenging for residents to eat healthy away from home. Poorer neighborhoods with a higher proportion of African American residents have fewer healthy options available, both in food selections and in food preparation; restaurants in these neighborhoods heavily promote unhealthy food options to residents. CONCLUSIONS: Environment is important in understanding health status: support for the healthy lifestyle associated with lower risks for disease is difficult in poorer communities with a higher proportion of African American residents. 相似文献