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51.
In this study, design optimization of a tooth implant-supported fixed prosthesis was investigated theoretically. A three-dimensional finite element analysis was utilized to simulate the stress distribution and deformation, with an emphasis on the material selection for various parts of the prosthesis. This mandibular prosthesis was supported by six implants. The properties of 3 different materials for implants and 4 different materials for framework were incorporated into 12 different models. For the loading conditions used, it was found that the largest displacements occurred at the far ends of the framework and that the resulting deflection was highly dependent on the material properties of the framework. The simulations showed that the stress in the framework was mainly concentrated near the holes in the lower surface and that the highest values of von Mises stresses occurred in the lingual part of the prosthesis. Furthermore, the modeling results revealed that more rigid frameworks led to a corresponding decreased stress in the retaining screws and that high-stress concentration areas moved from the neck of the implant towards the base of it, as the value of Young's modulus increased. It was concluded that the first best model was the Cr-Co alloy for the framework and the Ti alloy for the implant and the second best choice was the Cr-Co alloy for both the framework and the implant.  相似文献   
52.
Background: A recently published prospective study identified an impaired outcome of patients with non-perimesencephalic (NPM) subarachnoid hemorrhage (SAH). Our objective was to analyze the long-term outcome of patients with subsequent rehabilitation after NPM SAH.

Methods: A comparison of patients with NPM SAH receiving subsequent in-patient rehabilitation was done at discharge (using the modified Rankin scale (mRS)), short-term outcome after 6 months (mRS), and prospectively using a questionnaire (short-form health survey with 36 questions (SF-36)), which was sent to 66 patients.

Results: Thirty-seven patients answered the SF-36, on average 6.3 years after ictus (range 1.5–14 years). After NPM SAH, the mRS is impaired. Patients with subsequent rehabilitation had a significant better improvement until short-term follow-up. Until long-term outcome, the psychological items were non-significantly reduced, whereas all physical items (physical functioning, role limitations because of physical health problems, bodily pain, and general health perceptions) were significantly decreased compared to the standard population. In patients with subsequent rehabilitation, all items were only non-significantly reduced. About 16% of the patients developed secondary neurological and/or psychiatric diseases.

Conclusions: The quality of life (QoL) is decreased after NPM SAH. In the long-term follow-up, a significant reduction in physical items was identified. Due to subsequent in-patient rehabilitation after NPM SAH, the impairment can be improved significantly until short-term follow-up. Whereas patients with NPM SAH had a significantly decreased QoL at long-term follow-up, for patients with rehabilitation, the QoL was only slightly (non-significantly) reduced. Therefore, patients should receive subsequent rehabilitation after NPM SAH to improve the functional short-term outcome (mRS) and long-term QoL. www.clinicaltrials.gov (Identifier No. NCT02334657).  相似文献   
53.
The present study was performed to investigate the relation of Chlamydia trachomatis infection to sperm chromatin/DNA integrity in a population of infertile men (male partner of infertile couples) from Iran. Blood, semen and first‐void urine samples were obtained from 250 infertile men. Data were analysed with regard to the results of (i) serological analysis for specific antibodies to C. trachomatis in serum; (ii) the presence of C. trachomatis and DNA in first‐void urine; and (iii) in the semen sample of the male partner, in addition to sperm analysis, four different tests (aniline blue, chromomycin A3, acridine orange and TUNEL) were used to detect sperm chromatin and DNA abnormalities. The main conclusions of the results were: (i) no evidence of C. trachomatis infection in semen samples was found; (ii) sperm DNA fragmentation and chromatin studies were not correlated with C. trachomatis diagnosis; (iii) the percentage of DNA fragmentation is positively correlated with the percentage of immotile sperm but negatively with semen volume, normal morphology; and (iv) in sperm chromatin evaluations, only the percentage of chromatin protamination was related to male age.  相似文献   
54.
The anticonvulsant activity of the selective group II metabotropic glutamate receptor (mGlu) agonist 2R,4R-4-aminopyrrolidine-2,4-dicarboxylate (2R,4R-APDC) has been evaluated in chemoconvulsant and sound-induced models of epileptic seizures in DBA/2 mice. 2R,4R-APDC (> or =10 nmol, intracerebroventricularly (i.c.v.), -15 min) transiently reduced sound-induced seizure activity including clonic seizures to 40% of vehicle at 20 nmol (i.c.v.) and 30% of vehicle at 100 mg/kg (intraperitoneally (i.p.), -15 min). 2R,4R-APDC inhibited clonic seizures induced by the group III mGlu antagonist (R,S)-alpha-methylserine-O-phosphate (2.5 micromol, i.c.v.) when co-injected at 20-40 nmol and inhibited limbic seizure activity induced by the mGlu(1/5) agonist (R,S)-3,5-dihydroxyphenylglycine (1.5 micromol, i.c.v.) when co-injected at 10-40 nmol. A reversal of the anticonvulsant activity of 2R,4R-APDC was observed at (>20 nmol) in each of the chemoconvulsant and sound-induced models of epileptic seizures. 2R,4R-APDC (0.1-1 micromol, i.c.v.) induced stimulus-independent, rapid and dose-dependent clonic seizures. Selective mGlu(2/3) agonists represent a novel class of potential anti-epileptic drugs, however due to the proconvulsant activity observed here, 2R,4R-APDC is obviously limited in this regard.  相似文献   
55.
To investigate the effect of 5'-(N-ethylcarboxamido) adenosine (NECA), an adenosine agonist, on triggering angiogenesis in transplanted human ovarian tissue, the expression of angiopoietin-1 (Ang1), Ang2, vascular endothelial growth factor 121 (VEGF-121) and VEGF-189 at both gene and protein levels as well as the density of vasculature were studied in tissue fragments grafted to NECA-treated and control groups of nude mice. The results showed that NECA treatment triggered down-regulation of Ang1, induced VEGF-189 expression, and stimulated neovascularization, highlighting the beneficial effect of NECA on the process of angiogenesis.  相似文献   
56.
Anaphylactic reactions are of great importance in clinical allergology. Measurement of allergen concentration in foods is helpful to estimate their allergenicity. In this study, a sandwich ELISA for the evaluation of profilin concentration in fruits was designed. A mixture of monoclonal antibodies against saffron profilin was used as a capture antibody. The recombinant melon profilin was expressed in Escherichia coli BL-21 and applied as a standard antigen along with different fruit extracts to measure their profilin concentration. Furthermore, a polyclonal antibody against the recombinant melon profilin was produced and applied as the secondary antibody. In this way, the profilin concentration of various fruits including banana, tomato, kiwi, mulberry, cantaloupe, peach, watermelon and zucchini was measured. The results showed that the designed ELISA had a sensitivity threshold of about 1 ng/ml for the melon profilin and it is therefore suggested for determination of profilin concentration in other fruits.  相似文献   
57.
Sunitinib, a new vascular endothelial growth factor receptor inhibitor, has demonstrated activity in renal cell carcinoma and is now widely used in the palliative treatment of patients with metastatic renal cell carcinoma. It is generally well tolerated but has been associated with a low incidence of grade 3 and 4 toxicities including fatigue, diarrhea, anorexia, mucositis, skin toxicity, immune thrombocytopenic purpura, hypertension, hypothyroidism, cytopenias, and decreased cardiac ejection fraction. Thrombotic thrombocytopenic purpura-hemolytic uremic syndrome (TTP-HUS) is a rare condition that is severe and may be fatal. Several medications have been implicated in causing TTP-HUS including clopidogrel, mitomycin C, cisplatin. In this report, we describe a case of atypical HUS-microangiopathic hemolytic anemia during treatment with sunitinib in a patient with metastatic renal cell carcinoma. To our knowledge, this is the fourth case of microangiopathic hemolytic anemia associated with sunitinib described in the literature and the first case with fatal outcome despite treatment with plasmapheresis, dialysis, and withdrawal of sunitinib.  相似文献   
58.
Neurobehavioral stress has been shown to promote tumor growth and progression and dampen the immune system. In this study, we investigated whether inhibiting stress hormone production could inhibit the development of mammary carcinoma and metastasis in a rat model of breast carcinogenesis. To enhance β-endorphin (BEP), the endogenous opioid polypeptide that boosts immune activity and decreases stress, we generated BEP neurons by in vitro differentiation from fetal neuronal stem cells and transplanted them into the hypothalami of rats subjected to breast carcinogenesis. BEP-transplanted rats displayed a reduction in mammary tumor incidence, growth, malignancy rate, and metastasis compared with cortical cells-transplanted rats. BEP neuron transplants also reduced inflammation and epithelial to mesenchymal transition in the tumor tissues. In addition, BEP neuron transplants increased peripheral natural killer (NK) cell and macrophage activities, elevated plasma levels of antiinflammatory cytokines, and reduced plasma levels of inflammatory cytokines. Antimetastatic effects along with stimulation of NK cells and macrophages could be reversed by treatment with the opiate antagonist naloxone, the β-receptor agonist metaproterenol, or the nicotine acetylcholine receptor antagonist methyllycaconitine. Together, our findings establish a protective role for BEP against the growth and metastasis of mammary tumor cells by altering autonomic nervous system activities that enhance innate immune function.  相似文献   
59.
Electrohydrodynamic atomization (EHDA) is an attractive technique to make new types of composite particles for pharmaceutical use. The aim of this work is to prove that EHDA can be successfully used to attach nano/micro-particles of protein to lactose, the commonly used excipient for pulmonary delivery, keeping all the biological properties of the protein after dissolution of the complex. Bovine serum albumin (BSA) was used as a model protein. The atomization of BSA was tested with two different solvents, dimethyl sulfoxide (DMSO) and ethanol. The process using DMSO resulted in the formation of a thin layer of protein while the tests using ethanol resulted in the formation of spherical particles with mean diameters around 700 nm. Ethanol as solvent was also used to produce a composite formed by BSA adsorbed at the surface of lactose by electrostatic forces. No denaturation or significant conformational changes of the protein were observed, although an increase in the exposition of the lactose to the jet of the solution decreases the reproducibility of the method. Due to the absence of denaturation in the model protein, this new approach can be tested for the production of new formulations for dry powders for drug delivery systems.  相似文献   
60.
Anti-inflammatory effects of antidepressants have been reported in some studies, but the mechanisms underlying these effects remain unknown. Amitriptyline, a tricyclic antidepressant, is widely used in the management of psychological disorders and various types of pain, including neuropathic pain or fibromyalgia. In our previous work, we found the role of supraspinal mechanisms in the anti-inflammatory effect of amitriptyline. In the line of the indicated study, we sought to evaluate the effects of intraperitoneal (i.p.) and intracerebroventricular (i.c.v.) application of amitriptyline in the carrageenan-induced paw edema in rats in more details. Our findings confirmed that i.p. (40 and 80 mg/kg) and i.c.v. (100 μg/rat) injection of amitriptyline inhibited carrageenan-induced inflammation at different times. We also found that both i.p. and i.c.v. amitriptyline significantly decreased migration of polymorphonuclear (PMN) leucocytes into the site of inflammation, according to pathological evidence and the activity of myeloperoxidase (MPO). Furthermore, i.p. amitriptyline at the applied doses markedly reduced interleukin (IL)-1β and tumor necrosis factor (TNF)-α levels in the paw treated with carrageenan. Our results also showed that i.c.v. amitriptyline noticeably decreased the concentration of IL-1β in the inflamed paws. The TNF-α levels reduced in the i.c.v. group, even though these reductions were not statistically significant. These results confirmed the anti-inflammatory effects of systemic and central amitriptyline in the carrageenan-induced paw edema in rats, and demonstrated that these effects mediated mostly through the inhibition of PMN cells migration and release of IL-1β and TNF-α into the site of inflammation.  相似文献   
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