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L.L. Duarte L. Menna-Barreto M.A.L. Miguel F. Louzada J. Araújo M. Alam R. Areas M. Pedrazzoli 《Brazilian journal of medical and biological research》2014,47(4):316-320
Chronotype is an established concept designed to identify distinct phase
relationships between the expression of circadian rhythms and external synchronizers
in humans. Although it has been widely accepted that chronotype is subjected to
ontogenetic modulation, there is no consensus on the interaction between age and
gender. This study aimed to determine the relationship between age- and
gender-related changes in the morningness-eveningness character in a large sample of
people. A total of 14,650 volunteers were asked to complete the Brazilian version of
the Horne and Östberg chronotype questionnaire. The data demonstrated that, on
average, women were more morning-oriented than men until the age of 30 and there were
no significant differences between men and women from 30 to 45 years of age. In
contrast to the situation observed until the age of 30, women older than 45 years
were more evening-oriented than men. These results suggest that the ontogenetic
development of the circadian timekeeping system is more plastic in men, as
represented by the larger amplitude of chronotype changes throughout their aging
process. The phase delay of adolescence and phase advance of the elderly seem to be
phenomena that are more markedly present in men than in women. Thus, our data, for
the first time, provide support that sharply opposes the view that there is a single
path toward morningness as a function of age, regardless of gender. 相似文献
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William Marciel de Souza Gustavo Olszanski Acrani Marilia Farignoli Romeiro Osvaldo Reis Júnior Aline Lavado Tolardo Amanda Araújo Serrão de Andrade João Lídio da Silva Gonçalves Vianez Júnior Daniele Barbosa de Almeida Medeiros Márcio Roberto Teixeira Nunes Luiz Tadeu Moraes Figueiredo 《Archives of virology》2016,161(8):2325-2328
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Fátima Karoline Araújo Alves Dultra Adna Conceição Barros Helenemarie Schaer‐Barbosa Andréia Leal Figueiredo Clarissa Araújo Silva Gurgel Eduardo Antônio Gonçalves Ramos Ana Maria da Silva Carvalho Jean Nunes dos Santos 《Journal of oral pathology & medicine》2012,41(1):47-53
J Oral Pathol Med (2012) 41 : 47–53 Objective: The aim of this study was to investigate the presence of CD1a‐positive Langerhans cells and their relationship with E‐cadherin in minor salivary gland tumors. Methods: Twenty‐seven minor salivary gland tumors were investigated using immunohistochemistry for CD1a and E‐cadherin. Results: A significant difference regarding the mean density of CD1a‐positive Langerhans cells was observed between pleomorphic adenomas and malignant tumors studied (P = 0.001). No CD1a‐positive cells were detected in most cases (n = 5) of cystic adenoid carcinomas. CD1a‐positive cells were detected in one mucoepidermoid carcinoma case, and six low‐grade polymorphous adenocarcinomas cases. Comparison of the mean density of CD1a‐positive cells between the three malignant tumors showed no significant difference (P = 0.127). No significant difference was observed in the presence of E‐cadherin between tumors (P = 0.73), but it was detected in 24 cases. Conclusions: The lack of CD1a‐positive in malignant salivary gland tumors facilitates the neoplastic development and suggests that these cells might be useful as auxiliary diagnostic and prognostic tool in minor salivary gland tumors. Furthermore, it is suggested that E‐cadherin mediates cell adhesion in these tumors although we did not demonstrate significance. 相似文献
88.
Paulo Ricardo Saquete Martins-Filho Thiago de Santana Santos Vanessa Lessa Cavalcanti de Araújo Joanes Silva Santos Emanuel Sávio de Souza Andrade Luiz Carlos Ferreira da Silva 《Revista brasileira de otorrinolaringologia (English ed.)》2012,78(2):16-21
The traumatic bone cyst is characterized by the presence of an asymptomatic sinus devoid of epithelial lining, which is rarely found in the jaws.ObjectiveTo describe the clinical, surgical and radiographic findings of traumatic bone cysts.Material and MethodA retrospective study was made of patients diagnosed with traumatic bone cysts at an oral pathology department from 1992 to 2007. Data on the clinical, radiographic and surgical complications were gathered.ResultsTwenty-six cases of traumatic bone cyst were diagnosed in 15 years; 17 were male and 09 were female. Most patients were within first two decades of life and had no pain or history of trauma in the affected area. The multilocular pattern was observed in only seven cases, its radiographic appearance suggests a tumor. Air was found inside the lesion in about 70% of cases; serous fluid with blood and blood only were uncommon within the lesions.ConclusionA higher prevalence in young patients, absence of a history of trauma, and a small number of lesions containing serous fluid with blood reflects the need to discuss the true pathogenesis of traumatic bone cysts. 相似文献
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Fernanda Monego Rafael Silva Duarte Sueli Massumi Nakatani Wildo Navegantes Araújo Irina Nastassja Riediger Sonia Brockelt Verena Souza Jamyra Iglesias Cataldo Rubens Clayton da Silva Dias Alexander Welker Biondo 《The Brazilian journal of infectious diseases》2011,15(5):436-441
ObjectiveOne hundred thirty-one cases of postsurgical infections were reported in Southern Region of Brazil between August 2007 and January 2008. Thirty-nine (29.8%) cases were studied; this report describes epidemiological findings, species identification, antimicrobial susceptibility and clonal diversity of rapidly growing mycobacteria isolated in this outbreak.MethodsAll 39 isolates were analyzed by Ziehl-Nielsen stained smear, bacterial culture and submitted to rpoB partial gene sequencing for identification. The isolates were also evaluated for their susceptibility to amikacin, cefoxitin, clarithromycin, ciprofloxacin, doxycycline, tobramycin and sulfamethoxazole.ResultsThirty-six isolates out of the confirmed cases were identified as Mycobacterium massiliense and the remaining three were identified as Mycobacterium abscessus, Mycobacterium chelonae and Mycobacterium fortuitum. All M. massiliense isolates were susceptible to amikacin (MIC90 = 8 μg/mL) and clarithromycin (MIC90 = 0.25 μg/mL) but resistant to cefoxitin, ciprofloxacin, doxycycline, tobramycin and sulfamethoxazole. Molecular analysis by pulsed-field gel electrophoresis clustered all 36 M. massiliense isolates and showed the same pattern (BRA 100) observed in three other outbreaks previously reported in Brazil.ConclusionsThese findings suggest a common source of infection for all patients and reinforce the hypotheses of spread of M. massiliense BRA100 in Brazilian hospital surgical environment in recent years. 相似文献
90.
The recent medical literature has been using the term vulnerability to refer to harm to human integrity. The concept is multifaceted. Bioethics researchers conceive vulnerability as one of the basic anthropological features of the human condition. On the other hand, some bioethics scholars advocate using the terms susceptibility or variable vulnerability to refer to diseased or destitute populations. Also, frailty and variable vulnerability are correlated but not equivalent conditions which have been described somehow interchangeably in the recent medical literature, especially in the study of the ageing phenomena. The extremes of age are especially vulnerable periods of life and there has been growing evidence that neonatal and early life events have long-term influence on both the ageing process and frailty. This paper discusses some issues relevant to vulnerability and frailty and how one could possibly distinguish between them. There is still much to be learned about how frailty and variable vulnerability affect the ageing process across the life span. 相似文献