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991.
Mishra V Mishra M Ansari KM Chaudhari BP Khanna R Das M 《European journal of cancer (Oxford, England : 1990)》2012,48(13):2075-2085
Carcinogenic potential of argemone oil (AO) and butter yellow (BY), the adulterants encountered in edible oil, in gall bladder of Swiss albino mice was undertaken to investigate the potential aetiological factors of gall bladder carcinoma (GBC) in the Indo-Gangetic basin. Twice weekly intraperitoneal (ip) administration of AO (5 ml/kg body wt) and BY (25 mg/kg body wt) to Swiss albino male and female mice for 30 and 60 days indicated that females were more vulnerable to these adulterants in terms of responses to inflammatory markers. Subsequent experiments with dietary exposure of AO (1%) and BY (0.06%) for 6 months in female mice showed symptoms related to cachexia, jaundice and anaemia. High levels of total cholesterol, low density lipoprotein (LDL), TG, bilirubin and low level of high density lipoprotein (HDL) as well as gallstone formation was shown by AO exposure only, leading to the development of adenocarcinoma. BY exposure resulted in adenoma and hyperplasia without stone formation. The cyclooxygenase (COX-2) overexpression was found to be related to prostaglandin E2 (PGE2) production in AO treated mice but not in BY exposed animals, thereby indicating a differential pathway specific carcinogenicity. PGE2 stimulates the secretion of secreted mucins (MUC5AC), which is involved in stone formation following AO exposure. Enhanced secretion of membrane bound mucins (MUC4) in BY and AO exposed mice resulted in the activation of ErbB2 and downstream signalling such as p-AKT, p-ERK and p-JNK, which ultimately affects the target proteins, p53 and p21 leading to adenoma and adenocarcinoma, respectively. The study suggests that AO and BY are responsible for producing GBC in mice along with stone formation in the AO exposed animals. 相似文献
992.
Mishra MV Andrews DW Glass J Evans JJ Dicker AP Shen X Lawrence YR 《Journal of neuro-oncology》2012,107(3):591-597
Optic nerve gliomas (ONG) are rare astrocytic neoplasms. A paucity of literature exists on the epidemiology and outcomes of
ONG. Here, we present a series of 445 cases of ONG obtained from the Surveillance, epidemiology and end results (SEER) database.
Data on patient and tumor characteristics as well as initial treatment with surgery or radiation were extracted from the SEER
Database. Survival rates were calculated using the Kaplan–Meier method. A multivariate analysis was performed to determine
independent prognostic factors predicting mortality hazard ratios (HRs) using Cox proportional hazards modeling. The median
age range at diagnosis was 5–9 years. Twenty percent of patients were over the age of 20 years. Amongst patients with information
available on tumor grade (n = 131), 83% had a low-grade tumors and 17% had a high-grade tumors. Sixteen percent of patients received radiation therapy
and 18.4% of patient underwent a sub- or gross total resection. The 5 year overall survival was 96% and 20% for patients with
low- and high-grade tumors, respectively. In a multivariate analysis, grade was the only significant predictor of overall
survival (HR 29.3, CI: 4.3, 205.4, P < 0.001). Age at diagnosis, receipt of radiation therapy, and extent of surgical resection were not significantly correlated
with overall survival. In conclusion, ONG are rare tumors seen predominantly in children. The overall prognosis of high-grade
tumors remains poor in all age groups despite multi-modality treatment. 相似文献
993.
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995.
Endosulfan and Other Organochlorine Pesticide Residues in Maternal and Cord Blood in North Indian Population 总被引:1,自引:0,他引:1
Pathak R Suke SG Ahmed RS Tripathi AK Guleria K Sharma CS Makhijani SD Mishra M Banerjee BD 《Bulletin of environmental contamination and toxicology》2008,81(2):216-219
Humans are exposed to various environmental chemicals such as organochlorine pesticide residues, heavy metals, polychlorinatedbiphenyls (PCBs) etc. There is paucity of data regarding the present blood levels of organochlorine residues in North Indian population with reference to reproductive health. The present study was designed to analyze the levels of organochlorine pesticide residues in maternal and cord blood samples of normal healthy women with full term pregnancy to gain insight into the current status of pesticide burden in newborns. Hexachlorocyclohexane (HCH) contributed maximum towards the total organochlorine residues present in maternal and cord blood followed by endosulfan, pp' DDE and pp' DDT being the least. This is also the first report indicating endosulfan levels in this population. Our data indicates a transfer rate of 60-70% of these pesticides from mothers to newborns and this high rate of transfer of pesticides is of great concern as it may adversely affect the growth and development of newborn. 相似文献
996.
Analytical Method for Estimation of a New Insecticide Flubendiamide and its Safety Evaluation for Usage in Rice Crop 总被引:2,自引:0,他引:2
The paper presents a method for residue analysis of flubendiamide in rice (Oryza sativa), which includes improved extraction, cleanup and determination of flubendiamide in rice seeds, husk and straw by using LC
with UV detection. Safety evaluation of this insecticide in rice has been carried out after applying its soluble concentrate
(SC) formulation at recommended dose (30 g a.i. ha−1) and double of the recommended dose (60 g a.i. ha−1) on rice crop. MRL of flubendiamide on rice grain can be proposed as 0.2 mg kg−1. 相似文献
997.
Increasingly, measures of dietary patterns have been used to capture the complex nature of dietary intake and investigate its association with health. Certain dietary patterns may be important in the prevention of chronic disease; however, there are few investigations in adolescents. The aim of this study was to describe the dietary patterns of adolescents and their associations with sociodemographic factors, nutrient intakes, and behavioral and health outcomes. Analysis was conducted using data collected in the 1995 Australian National Nutrition Survey of participants aged 12-18 y who completed a 108-item FFQ (n = 764). Dietary patterns were identified using factor analysis and associations with sociodemographic factors and behavioral and health outcomes investigated. Factor analysis revealed 3 dietary patterns labeled a fruit, salad, cereals, and fish pattern; a high fat and sugar pattern; and a vegetables pattern, which explained 11.9, 5.9, and 3.9% of the variation in food intakes, respectively. The high fat and sugar pattern was positively associated with being male (P < 0.001), the vegetables pattern was positively associated with rural region of residence (P = 0.004), and the fruit, salad, cereals, and fish pattern was inversely associated with age (P = 0.03). Dietary patterns were not associated with socioeconomic indicators. The fruit, salad, cereals, and fish pattern was inversely associated with diastolic blood pressure (P = 0.0025) after adjustment for age, sex, and physical activity in adolescents > or = 16 y. This study suggests that specific dietary patterns are already evident in adolescence and a dietary pattern rich in fruit, salad, cereals, and fish pattern may be associated with diastolic blood pressure in older adolescents. 相似文献
998.
Constraint Preserving Schemes Using Potential-Based Fluxes I Multidimensional Transport Equations
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We consider constraint preserving multidimensional evolution equations.
A prototypical example is provided by the magnetic induction equation of plasma
physics. The constraint of interest is the divergence of the magnetic field. We design
finite volume schemes which approximate these equations in a stable manner and
preserve a discrete version of the constraint. The schemes are based on reformulating
standard edge centered finite volume fluxes in terms of vertex centered potentials.
The potential-based approach provides a general framework for faithful discretizations
of constraint transport and we apply it to both divergence preserving as well as curl
preserving equations. We present benchmark numerical tests which confirm that our
potential-based schemes achieve high resolution, while being constraint preserving. 相似文献
999.
Singal A Pandhi D Bhattacharya SN Das S Aggarwal S Mishra K 《International journal of dermatology》2008,47(1):44-47
A 10-year-old immunocompetent boy presented with multiple, verrucous, disseminated pheohyphomycotic lesions caused by Exophiala spinifera. The patient was not responsive to combination antifungal therapy (itraconazole, terbinafine, fluconazole) and cryotherapy. As antifungal susceptibility is known to be variable for Exophiala spinifera, in vitro sensitivity testing is recommended before medical treatment. This article reviews, in brief, all cases documented so far in the English literature. 相似文献
1000.