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1.
Forty-seven patients with oesophageal carcinoma were managed in 6 years' time. Average duration of illness was 5.5 months. History of chronic smoking and/or tobacco chewing was present in 80.85% of patients. Carcinoma included squamous cell variety (80.85%) and adenocarcinoma (19.15%). Thirty-one patients were in stage III while 16 patients were in stage II. Surgery included oesophagogastrectomy/oesophagogastrostomy (16 patients), feeding gastrostomy (11 patients), Mousseau-Barbin tube insertion (10 patients), only 10 patients were subjected to palliative radiotherapy. All patients after palliative treatment died within one year whereas 3-year and 5-year survivals after oesophagogastrectomy/oesophagogastrostomy were 68.75% and 31.25% respectively. Local lymph node metastasis adversely affected the 5-year survival rate.  相似文献   
2.
The advent of systems biology approaches that have stemmed from the sequencing of the human genome has led to the search for new methods to diagnose diseases. While much effort has been focused on the identification of disease-specific biomarkers, recent efforts are underway toward the use of proteomic and metabonomic patterns to indicate disease. We have developed and contrasted the use of both proteomic and metabonomic patterns in urine for the detection of interstitial cystitis (IC). The methodology relies on advanced bioinformatics to scrutinize information contained within mass spectrometry (MS) and high-resolution proton nuclear magnetic resonance (1H-NMR) spectral patterns to distinguish IC-affected from non-affected individuals as well as those suffering from bacterial cystitis (BC). We have applied a novel pattern recognition tool that employs an unsupervised system (self-organizing-type cluster mapping) as a fitness test for a supervised system (a genetic algorithm). With this approach, a training set comprised of mass spectra and 1H-NMR spectra from urine derived from either unaffected individuals or patients with IC is employed so that the most fit combination of relative, normalized intensity features defined at precise m/z or chemical shift values plotted in n-space can reliably distinguish the cohorts used in training. Using this bioinformatic approach, we were able to discriminate spectral patterns associated with IC-affected, BC-affected, and unaffected patients with a success rate of approximately 84%.  相似文献   
3.
The purpose of this study was to design a synthetic nanofibrillar matrix that more accurately models the porosity and fibrillar geometry of cell attachment surfaces in tissues. The synthetic nanofibrillar matrices are composed of nanofibers prepared by electrospinning a polymer solution of polyamide onto glass coverslips. Scanning electron and atomic force microscopy showed that the nanofibers were organized into fibrillar networks reminiscent of the architecture of basement membrane, a structurally compact form of the extracellular matrix (ECM). NIH 3T3 fibroblasts and normal rat kidney (NRK) cells, when grown on nanofibers in the presence of serum, displayed the morphology and characteristics of their counterparts in vivo. Breast epithelial cells underwent morphogenesis to form multicellular spheroids containing lumens. Hence the synthetic nanofibrillar matrix described herein provides a physically and chemically stable three-dimensional surface for ex vivo growth of cells. Nanofiber-based synthetic matrices could have considerable value for applications in tissue engineering, cell-based therapies, and studies of cell/tissue function and pathology.  相似文献   
4.
BACKGROUND AND PURPOSE: Single agent mitomycin c (MMC) has been shown to improve the outcome of radiotherapy in single institution trials. In order to confirm these findings in a broader worldwide setting, the International Atomic Energy Agency (IAEA) initiated a multicentre trial randomising between radiotherapy alone versus radiotherapy plus MMC. MATERIAL AND METHODS: Patients with advanced head and neck cancer were treated with primary curative radiotherapy (66 Gy in 33 fractions with five fractions per week) +/-a single injection (15 mg/m(2)) of MMC at the end of the first week of radiotherapy. Stratification parameters were tumour localization, T-stage, N-stage, and institution. A total of 558 patients were recruited in the trial from February 1996 to December 1999. Insufficient accrual and reporting led to the exclusion of three centres. The final study population consisted of 478 patients from seven centres. Patients had stage III (n=223) or stage IV (n=255) squamous cell carcinoma of the oral cavity (n=230), oropharynx (n=140), hypopharynx (n=65) or larynx (n=43). Prognostic factors like age, gender, site, size, differentiation and stage were well balanced between the two arms. RESULTS: The haematological side effects of MMC were very modest (<5% grade 3-4) and did not require any specific interventions. Furthermore, MMC did not enhance the incidence or severity of acute and late radiation side effects. Confluent mucositis and dry skin desquamation was common, occurring in 56% and 62% of patients, respectively. The overall 3-year primary locoregional tumour control, disease-specific and overall survival rates were 19, 36 and 30%, respectively. Gender, haemoglobin drop, tumour site, tumour and nodal stage were significant parameters for loco-regional tumour control. There was no significant effect of MMC on locoregional control or survival, except for the 161 N0 patients, where MMC resulted in a better loco-regional control (3-year estimate 16% vs. 29%, P=0.01). CONCLUSIONS: The study did not show any major influence of MMC on loco-regional tumour control, survival or morbidity after primary radiotherapy in stage III-IV head and neck cancer except in N0 patients where loco-regional control was significantly improved.  相似文献   
5.
This work was carried out to explore the compounds of bismuth with carbon using density functional theory (DFT)-based computations. The structures of the compounds BiC, BiC2, BiC3, Bi2C3, BiC5, and Bi2C5 were predicted at a generalized gradient approximation (GGA-PBE) level of theory. The calculations were carried out on the structures in unit cell and supercell geometries in slab and bulk periodicities. The structural and electronic properties of the mentioned compounds were investigated in detail. The calculations of the structures revealed lattice constants of the compounds for cubic unit cell as 212.2 pm for BiC, 176.9 pm for BiC2, 240.5 pm for BiC3, 232.4 pm for Bi2C3, and 354.5 pm for Bi2C5. The compounds BiC, BiC2, BiC3, BiC5, and Bi2C5 were found to be metallic, whereas Bi2C3 exhibited semiconducting character with a band gap of 0.305 eV. This work provides an initial framework for preparing new 2D materials from BixCy.  相似文献   
6.
Currently, the energy crisis is a hot topic for researchers because we are facing serious problems due to overpopulation and natural energy sources are vanishing day-by-day. To overcome the energy crisis, biofuel production from non-edible plant seeds is the best solution for the present era. In the present study, we select the non-edible seeds of Acacia farnesiana for biofuel production from different areas of Pakistan with better oil production results. Different kinds of analytical method, like the American Standard for Testing and Materials and techniques like Fourier transform infra-red spectroscopy, nuclear magnetic resonance spectroscopy, gas chromatography, and inductively coupled plasma optical emission spectrometry, were used to evaluate the chemical compositions. The maximum oil extraction rate (23%) was produced by petroleum ether. Potassium hydroxide exhibited the best conversion result of 96% fatty acid methyl ester. The transesterification method was used for the preparation of fatty acid methyl ester (96%) using potassium hydroxide and methanol. The viscosity and density of Acacia farnesiana seed oil biodiesel was comparable to American Standard for Testing Material biodiesel standards. By using gas chromatography-mass spectrometry, five fatty acids were detected comprising palmitic acid (6.85%), stearic acid (2.36%), oleic acid (12.13%), linoleic acid (46.85%), and α-linolenic acid (1.23%). This study concludes that Acacia farnesiana seed oil biodiesel could be an intriguing raw material for yielding Acacia farnesiana seed oil methyl ester as an alternative fuel source.

Currently, the energy crisis is a hot topic for researchers because we are facing serious problems due to overpopulation and natural energy sources are vanishing day-by-day.  相似文献   
7.
Neurological melioidosis is a very rare and very few cases have been reported from India. Presentation is an extremely varied and as this disease is associated with high mortality, high index of suspicion is needed to diagnose and treat. In this context, we report a patient presenting as Guillain Barre syndrome evaluated as melioidosis.Key Words: Guillain Barre’ syndrome, infection, melioidosis  相似文献   
8.
The present study concerns responsiveness of pre- and postsynaptic 5-hydroxytryptamine (5-HT)-1A receptors in a rat model of tardive dyskinesia (TD). Vacuous chewing movements (VCMs) in rats are widely accepted as an animal model of TD. Results show that haloperidol injected at a dose of 1 mg/kg twice a day for 5 weeks elicited VCMs, which increased in a time dependent manner following the drug administration for 3-5 weeks. Tolerance was produced in motor coordination during the potentiation of VCMs. Exploratory activity in an open field and in an activity box decreased in haloperidol treated animals. The effects of 8-hydroxy-2-(di-n-propylamino)tetraline (8-OH-DPAT; 0.5 mg/kg) were monitored 48-h after withdrawal from repeated administration of haloperidol. 8-OH-DPAT-induced locomotion was greater in haloperidol treated rats. 5-HT synthesis increased in haloperidol treated animals, while 8-OH-DPAT-induced decreases of 5-HT synthesis were greater in repeated haloperidol than repeated saline injected animals. The results suggest that an increase in the effectiveness of somatodendritic 5-HT-1A receptors may decrease the inhibitory influence of 5-HT on the activity of dopaminergic neurons to precipitate VCMs. The 5-HT-1A agonist may help to alleviate neuroleptic-induced TD.  相似文献   
9.
10.
Modern medicine has established three central antimicrobial therapeutic concepts: vaccination, antibiotics, and, recently, the use of active immunotherapy to enhance the immune response toward specific pathogens. The efficacy of vaccination and antibiotics is limited by the emergence of new pathogen strains and the increased incidence of antibiotic resistance. To date, immunotherapy development has focused mainly on cytokines. Here we report the successful therapeutic application of a complement component, a recombinant form of properdin (Pn), with significantly higher activity than native properdin, which promotes complement activation via the alternative pathway, affording protection against N. menigitidis and S. pneumoniae. In a mouse model of infection, we challenged C57BL/6 WT mice with N. menigitidis B-MC58 6 h after i.p. administration of Pn (100 µg/mouse) or buffer alone. Twelve hours later, all control mice showed clear symptoms of infectious disease while the Pn treated group looked healthy. After 16 hours, all control mice developed sepsis and had to be culled, while only 10% of Pn treated mice presented with sepsis and recoverable levels of live Meningococci. In a parallel experiment, mice were challenged intranasally with a lethal dose of S. pneumoniae D39. Mice that received a single i.p. dose of Pn at the time of infection showed no signs of bacteremia at 12 h postinfection and had prolonged survival times compared with the saline-treated control group (P < 0.0001). Our findings show a significant therapeutic benefit of Pn administration and suggest that its antimicrobial activity could open new avenues for fighting infections caused by multidrug-resistant neisserial or streptococcal strains.Pneumococcal and meningococcal infectious diseases remain a serious threat to public health. Streptococcus pneumoniae is the leading cause of community-acquired pneumonia and a major cause of otitis media, septicemia, and meningitis (1, 2). S. pneumoniae is responsible for ∼1.2 million deaths per year worldwide, with young children and immunocompromised patients at particular risk (3). Neisseria meningitidis causes epidemic bacterial meningitis and septicemia, with high mortality in children and young adults (4). The impact of meningococcal disease on human health is defined by both the risk and the severity of invasive meningococcal infections, with unacceptably high mortality rates, ranging from 10% in patients under optimal clinical therapy with the latest generation of antibiotics to up to 40% in patients with untreated septicemia. Almost one-third of those who survive invasive infections are left with long-term disabilities and long-term morbidity. Globally, the World Health Organization estimates that ∼1.2 million cases of invasive meningococcal infections occur annually, leading to more than 135,000 fatalities (5).Vaccination programs have reduced the rates of infection in developed countries, but neonates and elderly adults remain especially vulnerable (6, 7). The efficacy of vaccination is further limited by the emergence of new strains of S. pneumoniae and N. meningitidis.The complement system plays a major role in the host resistance to both pathogens (813). Complement is activated via three routes: the classical pathway, the lectin pathway, and the alternative pathway. Activation of the classical and lectin pathways is mediated by specific recognition molecules. Binding of C1q to the bacterial surface or the Fc region of antibody initiates the classical pathway. The lectin pathway is initiated by carbohydrate recognition molecules, including mannan-binding lectin, ficolins, and collectin 11, which bind directly to bacterial polysaccharides. Activation of the classical or lectin pathway leads to the formation of a C3 convertase (C4b2a), which splits C3 into the biologically active fragments, C3b and C3a. C3b can bind covalently to an activating surface, and hundreds of molecules of C3b can be deposited in close proximity to the C3 convertase complex. Accumulation of C3b close to C4b2a forms the classical pathway C5 convertase C4b2a(3b)n, in which C4b and C3b form a binding site for C5, orienting it for cleavage by C2a (14, 15).The mechanisms initiating the alternative pathway are less well understood. It is widely accepted that the alternative pathway maintains a continuous state of low-rate activation, which is held in check by potent negative regulators of activation on nonactivating surfaces, such as the surface of host cells. Turnover of the alternative pathway is initiated either by the provision of C3b via the classical pathway, the lectin pathway, or complement-independent proteolysis of C3 or by the spontaneous hydrolysis of C3 to form C3(H2O). C3b or C3(H2O) bind factor B to form either the C3bB or C3(H2O)B zymogen complex. In this complex, factor B is cleaved by factor D, releasing a Ba fragment. The activated C3bBb or C3(H2O)Bb fragments are themselves C3 convertases, which in turn cleave more C3 into C3a and C3b. Unchecked, the accumulation of C3b rapidly leads to the formation of more alternative pathway convertase complexes, resulting in a physiologically critical positive feedback mechanism—the amplification loop of complement activation (16). The alternative pathway thus amplifies complement activation initiated by any of the three pathways, making it an attractive target for therapeutic intervention designed to modulate complement-mediated immunity and/or inflammatory processes (17).Deposition of C3b and iC3b on the bacterial surface is a key step in the immune response against S. pneumoniae, because complement-mediated opsonisation is essential for clearance of S. pneumoniae through phagocytosis (8). Lysis of bacteria, owing to formation of the membrane attack complex complex, is the critically important biological activity of complement in the defense against N. meningitidis (10). Inherited or acquired deficiencies of the alternative pathway are associated with a high risk of recurrent bacterial infection. Factor B deficiencies significantly increase the risk of S. pneumoniae and Pseudomonas aeruginosa infection (9, 18). In a mouse model of properdin deficiency, the severity of polymicrobial peritonitis was significantly greater in deficient mice compared with their WT littermates (19). Properdin deficiency in humans has been associated with a high risk of meningococcal infections, especially with unusual infective serotypes, such as W-135 and Y (10, 20, 21). In addition, opsonophagocytosis of S. pneumoniae was found to be severely compromised in properdin-deficient sera, and reconstitution of properdin-deficient sera with purified properdin restored the opsonic activity and killing of S. pneumoniae by polymorphonuclear leukocytes (22, 23).Properdin is the only known positive physiological regulator of complement activation. It stabilizes and extends the half-life of the surface-bound C3 convertase C3bBb, and inhibits its degradation by factor I (2426). In their pioneering 1954 work, Pillemer et al. (26) first described properdin as a serum protein that mediates complement activation and antimicrobial activity in absence of antibodies.Properdin is present in serum at a concentration of ∼5–15 μg/mL (27). Unlike most other complement components, properdin is not synthesized in the liver but rather is expressed by other cells, including monocytes, T cells, mast cells, and granulocytes (19, 2830). Properdin monomers can assemble into dimers (P2), trimers (P3), and tetramers (P4), formed by head-to-tail association of monomers (each ∼53 kDa) (31, 32). Properdin aggregates, so-called “activated” properdin (Pn), are considered artificial higher-order oligomers formed during the purification of properdin from plasma or during subsequent freeze–thaw cycles (33). The functional activity of properdin increases with the size of the polymers formed (34). By increasing the half-life of the alternative pathway C3 convertase, properdin antagonizes the functional activity of complement factor H, an abundantly expressed plasma component, which promotes inactivation of the alternative pathway C3 convertase and of all C5 convertases of complement by accelerating the decay of these enzyme complexes through binding to complex-bound C3b and by serving as a cofactor in the factor I-mediated conversion of C3b to its inactive form, termed iC3b (35). Interestingly, the two pathogens used in this study were previously shown to express distinct microbial surface components that sequester factor H from host plasma, leading to resistance to the complement-mediated immune clearance of these pathogens (36, 37).In the present study, we addressed the role of the alternative pathway and the effect of administration of recombinant properdin as a tool for boosting alternative pathway activity to augment the immune response against S. pneumoniae or N. meningitidis.  相似文献   
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