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排序方式: 共有449条查询结果,搜索用时 15 毫秒
71.
D. S. Manjegowda P. Karunakar N. B. Ramachandra 《Indian journal of pharmaceutical sciences》2015,77(6):735-741
Congenital heart disease is the most common type of birth defect. The single nucleotide polymorphism in GATA4 is associated with various congenital heart disease phenotypes. In the present study, we analysed the nonsynonymous single nucleotide polymorphism of GATA4, which are involved in congenital heart disease by predicting the changes in protein structures. Total of 49 nonsynonymous single nucleotide polymorphisms of GATA4 was screened from congenital heart disease patients of Mysore and also globally reported nonsynonymous single nucleotide polymorphisms. To understand the role of nonsynonymous single nucleotide polymorphisms, we mutated the sequence and translated into amino acids. Further the mutated protein secondary structure is predicted and tertiary structure is predicted using homology modeling. The quantitative evaluation of protein structure quality was verified with Volume Area Dihedral Angle Reporter server. Results revealed the secondary, tertiary structural changes along with changes in free energy of folding, volume and accessible surface area. Thus, the structural changes in the mutated proteins impaired the normal function of GATA4. 相似文献
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73.
Khatri R Memon MZ Zacharatos H Taqui AM Qureshi MH Vazquez G Suri MF Rodriguez GJ Tummala RP Ezzeddine MA Qureshi AI 《Neurocritical care》2011,15(1):28-33
Background
Percutaneous transluminal angioplasty (PTA) has been introduced for treatment of symptomatic cerebral vasospasm in patients with subarachnoid hemorrhage (SAH). While angiographic improvement is consistently reported, clinical improvement following the procedure varies, and limited data is available regarding overall impact on outcome.Methods
The authors performed a retrospective analysis of all hospital admissions with aneurysmal SAH over a 6 year period. The length of stay, discharge outcomes (measured by modified Rankin scale [mRS] at discharge), and 1-year mortality among patients with SAH before (4 year period) and after (2 year period) institution of PTA for cerebral vasospasm were compared. Embolization for intracranial aneurysm was used as a therapeutic option throughout the study duration. The effect of institution of PTA for vasospasm after adjusting for age, clinical severity, and use of aneurysm embolization on both discharge outcomes and 1-year mortality in multivariate analysis was evaluated.Results
A total of 146 patients with aneurysmal SAH were admitted during the study duration. There was no difference between the 89 patients admitted in pre-angioplasty period and 57 patients admitted in post-angioplasty period in regards to age, medical co-morbidities, and admission clinical severity of patients (measured by Hunt and Hess grade and Glasgow coma scale). A total of 18 (32%) patients underwent PTA with or without intra-arterial vasodilator treatment in the second period of the study. There was a non significant decrease in rates of severe disability and death (mRS 5–6) at discharge (45 vs. 33%, P = 0.09) and 1-year mortality (32 vs. 22%, P = 0.26) after introduction of PTA for cerebral vasospasm after adjusting for potential confounders. There was no significant difference between the two time periods in regards to length of stay.Conclusion
A non significant trend was noted with reduced rate of severe disability and mortality at discharge and 1-year mortality after the introduction of PTA for cerebral vasospasm associated with SAH without increasing the length of hospital stay. 相似文献74.
Role of phagosomes and major histocompatibility complex class II (MHC-II) compartment in MHC-II antigen processing of Mycobacterium tuberculosis in human macrophages 下载免费PDF全文
Torres M Ramachandra L Rojas RE Bobadilla K Thomas J Canaday DH Harding CV Boom WH 《Infection and immunity》2006,74(3):1621-1630
Mycobacterium tuberculosis resides in phagosomes inside macrophages. In this study, we analyzed the kinetics and location of M. tuberculosis peptide-major histocompatibility complex class II (MHC-II) complexes in M. tuberculosis-infected human macrophages. M. tuberculosis peptide-MHC-II complexes were detected with polyclonal autologous M. tuberculosis-specific CD4+ T cells or F9A6 T hybridoma cells specific for M. tuberculosis antigen (Ag) 85B (96-111). Macrophages processed heat-killed M. tuberculosis more rapidly and efficiently than live M. tuberculosis. To determine where M. tuberculosis peptide-MHC-II complexes were formed intracellularly, macrophages incubated with heat-killed M. tuberculosis were homogenized, and subcellular compartments were separated on Percoll density gradients analyzed with T cells. In THP-1 cells, M. tuberculosis Ag 85B (96- 111)-DR1 complexes appeared initially in phagosomes, followed by MHC class II compartment (MIIC) and the plasma membrane fractions. In monocyte-derived macrophages, M. tuberculosis peptide-MHC-II complexes appeared only in MIIC fractions and subsequently on the plasma membrane. Although phagosomes from both cell types acquired lysosome-associated membrane protein 1 (LAMP-1) and MHC-II, THP-1 phagosomes that support formation of M. tuberculosis peptide-MHC-II complexes had increased levels of both LAMP-1 and MHC-II. Thus, M. tuberculosis phagosomes with high levels of MHC-II and LAMP-1 and MIIC both have the potential to form peptide-MHC-II complexes from M. tuberculosis antigens in human macrophages. 相似文献
75.
Naturally elicited antibodies to glycosylphosphatidylinositols (GPIs) of Plasmodium falciparum require intact GPI structures for binding and are directed primarily against the conserved glycan moiety 下载免费PDF全文
Immunization with a synthetic glycan corresponding to Plasmodium falciparum glycosylphosphatidylinositols (GPIs) has been proposed as a vaccination strategy against malaria. We investigated the structural requirements for binding of naturally elicited anti-GPI antibodies to parasite GPIs. The data show that anti-GPI antibody binding requires intact GPI structures and that the antibodies are directed predominantly against GPIs with a conserved glycan structure with three mannoses and marginally against the terminal fourth mannose. The results provide valuable insight for exploiting GPIs for the development of malaria vaccines. 相似文献
76.
Refractive index dispersion is an intrinsic optical property and a useful source of contrast in biological imaging studies. In this report, we present the first dispersion phase imaging of living eukaryotic cells. We have developed quantitative dispersion microscopy based on the principle of quantitative phase microscopy. The dual-wavelength quantitative phase microscope makes phase measurements at 310 nm and 400 nm wavelengths to quantify dispersion (refractive index increment ratio) of live cells. The measured dispersion of living HeLa cells is found to be around 1.088, which agrees well with that measured directly for protein solutions using total internal reflection. This technique, together with the dry mass and morphology measurements provided by quantitative phase microscopy, could prove to be a useful tool for distinguishing different types of biomaterials and studying spatial inhomogeneities of biological samples. 相似文献
77.
Extraspinal ependymomas are rare. The majority occur in the sacrococcygeal region. The subcutaneous variety accounts for approximately two thirds of cases, which are commonly misdiagnosed as a pilonidal cyst or sinus. Treatment is complete surgical resection. The role of coccygectomy is controversial. Adjuvant radiotherapy is of benefit to those with an incompletely excised tumour. Up to 20% metastasise, chiefly to the inguinal lymph glands, but pulmonary metastases are also reported. Palliative chemotherapy has not been shown to be of any benefit. Long term follow-up is important as metastases can occur up to 20 years after initial presentation. We report a 37-year-old woman with a subcutaneous sacrococcygeal ependymoma with iliac lymph nodal metastasis at presentation. 相似文献
78.
79.
Pranathi Ramachandra Sara Booth Thirza Pieters Kalliopi Vrotsou Felicia A. Huppert 《Psycho-oncology》2009,18(12):1323-1326
Background: Patients with cancer have relatively high rates of anxiety and distress, adversely affecting their well‐being and quality of life. Recent studies indicate that addressing these symptoms could result in better response to cancer treatment. Researchers have found that interventions that focus on increasing mental awareness and the frequency of positive experiences may have a greater impact on reducing psychological morbidity and increasing quality of life than interventions that target relief of psychological symptoms. Aim: To develop and test a brief, easy to use intervention that could improve well‐being and quality of life in cancer patients. Methods: We developed a simple well‐being intervention that made few demands on patient time and required little training resource. Participants were randomly assigned to an intervention group or a deferred entry group. Measures of anxiety, depression, well‐being and quality of life were administered at baseline and at follow‐ups. Results: Twenty‐two women with metastatic breast cancer and 24 men with metastatic prostate cancer were recruited from oncology clinics. Thirteen women and 14 men completed the study. Both qualitative and quantitative data showed that the intervention was acceptable to users. There was statistically significant improvement in quality of life scores on WHOQOL‐BREF post‐intervention (p=0.046). Compliance with the intervention was good. Conclusions: This brief well‐being intervention appears to be a promising technique for improving quality of life of cancer patients, without making undue demands on staff resources or patient time. If further studies confirm its effectiveness, it could prove to be a cost‐effective intervention. Copyright © 2009 John Wiley & Sons, Ltd. 相似文献
80.
PURPOSE: The purpose of this report was to describe an uncommon wavelike epitheliopathy after phacoemulsification in a 59-year-old man with well-controlled diabetes mellitus. METHODS: Retrospective case report. RESULTS: A 59-year-old man with a history of well-controlled diabetes mellitus presented to us with irritation and blurring of vision in the right eye of 4-month duration after phacoemulsification with multifocal intraocular lens implantation. Slit-lamp examination revealed a wave-like epitheliopathy in the right cornea, extending nasally from the incision area. Corneal sensation was reduced. Confocal microscopy revealed reduced subbasal nerve plexus and unhealthy corneal epithelium. Topical application of preservative-free lubricants was advised. On follow-up examinations, it was observed that the disappearance of the epitheliopathy correlated with the regeneration of the nerve plexus, as shown by the in vivo confocal microscopy findings. CONCLUSIONS: This is an isolated case report of a wavelike epitheliopathy after phacoemulsification. The regeneration of the subbasal nerve plexus correlating with the disappearance of the epitheliopathy suggests an element of neurotrophic corneal damage. Other probable mechanisms are discussed along with the in vivo confocal microscopy findings. 相似文献