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31.
Saura C. Sahu Joyce Njoroge Steven M. Bryce Jiwen Zheng John Ihrie 《Journal of applied toxicology : JAT》2016,36(4):521-531
Exposure to nanosilver found in food‐ and cosmetics‐related consumer products is of public concern because of the lack of information about its safety. In this study, two widely used in vitro cell culture models, human liver HepG2 and colon Caco2 cells, and the flow cytometric micronucleus (FCMN) assay were evaluated as tools for rapid predictive screening of the potential genotoxicity of nanosilver. Recently, we reported the genotoxicity of 20 nm nanosilver using these systems. In the current study presented here, we tested the hypothesis that the nanoparticle size and cell types were critical determinants of its genotoxicity. To test this hypothesis, we used the FCMN assay to evaluate the genotoxic potential of 50 nm nanosilver of the same shape, composition, surface charge and obtained from the same commercial source using the same experimental conditions and in vitro models (HepG2 and Caco2) as previously tested for the 20 nm silver. Results of our study show that up to the concentrations tested in these cultured cell test systems, the smaller (20 nm) nanoparticle is genotoxic to both the cell types by inducing micronucleus (MN). However, the larger (50 nm) nanosilver induces MN only in HepG2 cells, but not in Caco2 cells. Also in this study, we evaluated the contribution of ionic silver to the genotoxic potential of nanosilver using silver acetate as the representative ionic silver. The MN frequencies in HepG2 and Caco2 cells exposed to the ionic silver in the concentration range tested are not statistically significant from the control values except at the top concentrations for both the cell types. Therefore, our results indicate that the ionic silver may not contribute to the MN‐forming ability of nanosilver in HepG2 and Caco2 cells. Also our results suggest that the HepG2 and Caco2 cell cultures and the FCMN assay are useful tools for rapid predictive screening of a genotoxic potential of food‐ and cosmetics‐related chemicals including nanosilver. Published 2016. This article is a U.S. Government work and is in the public domain in the USA. 相似文献
32.
Sahu B Ozturk O Deo N Fordham K Ranierri M Serhal P 《Journal of assisted reproduction and genetics》2008,25(1):1-5
Purpose In women the relationship between myotonic dystrophy type I and fertility remains controversial. The objective of this study
was to evaluate the ovarian reserve, ovarian response to stimulation and oocyte quality in these patients.
Materials and methods We compared 15 myotonic dystrophy type I patients with 39 age matched controls with isolated male factor infertility necessitating
ICSI.
Results All parameters of ovarian reserve (day 3 FSH and E2, antral follicle count and delta E2) were significantly better in the
controls. Despite having significantly lower doses of gonadotrophin, the control group attained a higher number of retrieved
oocyte–cumulus complexes (p < 0.04). Analysis of cytoplasmic and extracytoplasmic dysmorphism did not reveal any difference between the two groups. Fertilisation
rate and top grade embryos on day 3 were similar in both groups.
Conclusion The present study suggests that though women with myotonic dystrophy type I have a reduced ovarian reserve and respond poorly
to controlled ovarian stimulation, there is no impact on oocyte and embryo quality. Hence suggesting that successful ART is
feasible with appropriate selection in women with mild myotonic dystrophy.
Capsule Women with myotonic dystrophy type I have reduced ovarian reserve and respond poorly to controlled ovarian stimulation, though
there is no impact on oocyte quality. 相似文献
33.
Prevalence of pathology in women attending colposcopy for postcoital bleeding with negative cytology
Objective To determine the frequency of cervical pathology and the incidence of cervical neoplasia in women presenting with PCB at the
colposcopy clinic with negative cytology.
Design A retrospective study.
Setting A district general hospital.
Population Eighty-seven women with postcoital bleeding and negative cytology were seen in the colposcopy unit during 1 January 2003 to
31 December 2005.
Methods Women were identified from computer records and details were extracted from the case notes.
Main outcome measure Histopathological diagnosis.
Results Six women (6.9%) had cervical intraepithelial neoplasia. There were no cases of invasive cancer. Thus in our study 6.9% women
with postcoital bleeding had abnormal histology even though they had normal smears. Other identifiable causes were cervical
polyp (12.5%), ectopy (33.6%) and Chlamydia (2.3%). No pathology was found in 50% of women.
Conclusion Women with postcoital bleeding even with normal smears appear to be at much greater risk of cervical neoplasia than the general
population. Unfortunately there is no general consensus for management of these patients. Hence further research is needed
to standardise the management of women with PCB. Patients should be reassured that in vast majority of cases no serious pathology
is detected. 相似文献
34.
Agarwal A Chowdhary P Das V Srivastava A Pandey A Sahu MT 《The journal of obstetrics and gynaecology research》2007,33(5):651-654
AIM: Management of post cesarean pregnancy continues to be a dilemma. The present study was undertaken to evaluate the outcome of such pregnancies in a resource constrained setting so that an appropriate management protocol can be decided. METHODS: An observational study was conducted in the Department Of Obstetrics And Gynecology, King George's Medical University, Lucknow, India. The outcome of all of the women admitted with pregnancy with a previous cesarean section was noted. RESULTS: A total number of 447 women with a post cesarean pregnancy underwent delivery. These comprised 13.7% of total deliveries over the same period. 124 women (27.7%) had successful vaginal delivery while 323 (72.3%) had a repeat cesarean section. Maternal morbidity and perinatal mortality were both significantly higher in the vaginal delivery group (P = 0.00211 and P = 0.0426, respectively). CONCLUSIONS: Vaginal birth after cesarean (VBAC) is associated with higher maternal morbidity and perinatal mortality. Therefore the decision for VBAC must be taken only after proper consideration and counseling of the couple. 相似文献
35.
36.
Sachin Malik Suroor A. Khan Priya Ahuja Satish K. Arya Shikha Sahu Kapendra Sahu 《Medicinal chemistry research》2013,22(12):5633-5653
Malaria is the leading infectious disease found in humans, affecting third-world countries. Worldwide, more than two billion people are at risk of malaria, with about 500 million clinical cases of malaria each year and one million deaths. In this focused review, an effort has been made to summarize the reactions of singlet oxygen with organic substrates, their stereoselectivity, stereospecificity and utilization in generating dioxetanes and endoperoxides. The study of production and reactivity indications of this exceptional molecule has emerged as a rich and diverse area in the synthesis of antimalarials like artemisinin and its semisynthetic derivatives, structurally simple 1,2,4-trioxanes, sesquiterpene isonitriles, synthetic cyclic, and other acyclic peroxides. Artermisinin, a mainstay in antimalarial drug therapy, meets the dual challenge posed by drug-resistant parasites and rapid advancement of lethal malarial threat. The cardinal mechanism of peroxidation and ring closure in its production are induced by singlet oxygen and acid. Moreover, its complex structure restricts the complete chemical synthesis of artemisinin. Consequently, the limited availability coupled with increasing demand for artemisinin has paved the way for the preparation of synthetic alternatives of artemisinin and its derivatives. Likewise, past evidence of the structure–activity relationship indicate the importance of singlet oxygen in antimalarial drug synthesis. It is anticipated that this compendium on the chemistry of singlet oxygen will be of use to organic/medicinal chemists and pharmacologists working on antimalarial drug development. 相似文献
37.
Priyadarshi Soumyaranjan Sahu Jyotsna Seepana Sudarsini Padela Abani Kanta Sahu Swarna Subbarayudu Ankur Barua 《Revista do Instituto de Medicina Tropical de S?o Paulo》2014,56(3):253-258
Neurocysticercosis (NCC) is one of the major causes of childhood seizures
in developing countries including India and Latin America. In this study neurological
pediatric cases presenting with afebrile seizures were screened for anti-Cysticercus
antibodies (IgG) in their sera in order to estimate the possible burden of
cysticercal etiology. The study included a total of 61 pediatric afebrile seizure
subjects (aged one to 15 years old); there was a male predominance. All the sera were
tested using a pre-evaluated commercially procured IgG-ELISA kit (UB-Magiwell
Cysticercosis Kit ™). Anti-Cysticercus antibody in serum was positive in 23 of 61 (37.7%)
cases. The majority of cases with a positive ELISA test presented with generalized
seizure (52.17%), followed by complex partial seizure (26.08%), and simple partial
seizure (21.73%). Headaches were the major complaint (73.91%). Other presentations
were vomiting (47.82%), pallor (34.78%), altered sensorium (26.08%), and muscle
weakness (13.04%). There was one hemiparesis case diagnosed to be NCC. In this study
one child without any significant findings on imaging was also found to be positive
by serology. There was a statistically significant association found between the
cases with multiple lesions on the brain and the ELISA-positivity (p
= 0.017). Overall positivity of the ELISA showed a potential cysticercal etiology.
Hence, neurocysticercosis should be suspected in every child presenting with afebrile
seizure especially with a radio-imaging supportive diagnosis in tropical developing
countries or areas endemic for taeniasis/cysticercosis. 相似文献
38.
Arthi Sridhar B. M. Sunil Kumar Aarathi Rau A. T. K. Rau 《Indian journal of hematology & blood transfusion》2017,33(2):222-227
Dengue Fever (DF) may evolve into two life threatening forms—Dengue Hemorrhagic Fever (DHF) and Dengue Shock Syndrome (DSS). DHF is associated with increased vascular permeability and plasma leakage causing thrombocytopenia and loss of clotting factors into the third space and may result in bleeding initially due to thrombocytopenia and later due to disseminated intravascular coagulation (DIC), often as a terminal event. Prompt recognition and treatment of minor bleeds in DF children with incipient DIC with component therapy may be associated with improved survival while failure to do so is usually catastrophic. A sensitive marker for early DIC is the presence of D-dimer (DD) in the blood. To determine the correlation between the severity of thrombocytopenia and early DIC in children with DHF. The impact of additional factors like age and shock will also be evaluated. Case control prospective study of 60 DHF sero -positive children (1–15 years) with thrombocytopenia. After clinical evaluation they were divided into two equal groups based on the degree of thrombocytopenia (more than/less than 30,000/mm3). PT/APTT and DD levels were estimated in all children of both groups and statistical correlation was done. There was no significant difference in the DD levels between the two groups. However, children in either group, presenting with clinical features of shock and thrombocytopenia had significantly higher DD levels. Empirical component therapy in children with DHF based purely on their low platelet counts may not be justified. However, in DHF children with thrombocytopenia and features of shock, aggressive component therapy may prevent subsequent bleeding and may be justified. 相似文献
39.
Sridhar Venkatachalam 《Current cardiology reports》2014,16(1):1-10
Based on several randomized clinical trials, carotid revascularization has been shown to reduce future stroke risk among individuals with severe asymptomatic carotid stenosis. However, a well-recognized problem with such prophylactic intervention is the risk of periprocedural stroke, death, or myocardial infarction. If actual stroke risk with asymptomatic carotid stenosis can be reduced significantly by aggressive medical management, carotid revascularization may yield marginal benefit or even cause harm especially in those with limited life expectancy. Based on recent observational data, it is becoming apparent that the stroke risk in this population has been declining with better medical management alone. This has prompted a few to avoid carotid revascularization for asymptomatic carotid stenosis altogether. Others feel such conclusions cannot be made with observational data alone. In the midst of this controversy, it is important that clinicians perform carotid revascularization on a case by case basis while ensuring optimal medical management in all patients. An algorithmic approach to decision making based on available evidence will enable clinicians to personalize patient management with efficiency. 相似文献
40.
Fragrance finishing of textile has been enormously increased and used in domestic and industrial application. Fragrance can be synthesis chemically but available in natural and inorganic. The investigation of this research is to study the combined effect of fragrance and antimicrobial finishing on cotton fabric by lavender essential oil with the use of β-Cyclodextrin, Chitosan citrate and β-Cyclodextrin/Grafted Chitosan through pad-dry method. Fourier Transform Infrared spectroscopy (FTIR) was used to study the formation of ester bonds between β-cyclodextrin/grafted chitosan and cotton celluloses. For all the finished fabric samples fragrance release rate performance and antimicrobial properties were measure by standard test methods. The results revealed that β-CD was highly soluble in 0.6 gpl NaOH solution and 80 gpl β-CD and 6% essential lavender oil solutions were found to be a most suitable combination for fragrance and antimicrobial finishing. FTIR studies reveal about the formation of a carboxylic ester between cotton and β-Cyclodextrin/Grafted Chitosan at 1730 cm?1 ester peak. 相似文献