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201.
K. Solarewicz-Madejek T. M. Basinski R. Crameri M. Akdis A. Akkaya K. Blaser K. F. Rabe C. A. Akdis M. Jutel 《Clinical and experimental allergy》2009,39(6):845-855
Background Bronchial smooth muscle cells (SMC) proliferate, express adhesion molecules, secrete cytokines and thus efficiently contribute to the pathogenesis of asthma.
Objective The aim of the study was to investigate whether, and by which mechanism, T cells and eosinophils can cause death of airway SMC.
Methods The T cell- and eosinophil-induced cell death was analysed in primary human bronchial SMC cultures as well as in bronchial biopsy specimens from non-asthmatic and asthmatic individuals.
Results Bronchial SMC death showed characteristic morphological features of apoptosis in 3–6 days cultures with inflammatory cytokines (IFN-γ, TNF-α), soluble death ligands [sFasL, TNF-related apoptosis-inducing ligand (TRAIL)] and activated T-helper type 1 (Th1) and Th2 cell supernatants. The recombinant eosinophil cationic protein induced SMC necrosis within 1 h. Resting SMC expressed the death receptors TNFR1, TNFR2, Fas, TRAILR1, TRAILR2 and membrane FasL as a death-inducing ligand. IFN-γ and TNF-α up-regulated TNFR1, TNFR2, Fas and membrane FasL on SMC. TNF-α up-regulated TRAILR1 and TRAILR2; sFasL up-regulated TNFR2. The intracellular caspase-3 activation in SMC was significantly increased by IFN-γ, sFasL, TRAIL, Th1 and Th2 cell supernatants. Increased expression of TRAIL in asthmatics, but not in non-asthmatic individuals was demonstrated in situ . The apoptosis receptors TRAILR1 and TRAILR2 were expressed in SMC and epithelial cells both in healthy and asthmatic biopsies. Prominent apoptosis of SMC was observed in fatal asthma, but not intermittent asthma biopses.
Conclusion The demonstration of bronchial SMC death both by apoptosis and necrosis indicates the essential role of T cells and eosinophils in the bronchial tissue injury particularly in the severe asthma. 相似文献
Objective The aim of the study was to investigate whether, and by which mechanism, T cells and eosinophils can cause death of airway SMC.
Methods The T cell- and eosinophil-induced cell death was analysed in primary human bronchial SMC cultures as well as in bronchial biopsy specimens from non-asthmatic and asthmatic individuals.
Results Bronchial SMC death showed characteristic morphological features of apoptosis in 3–6 days cultures with inflammatory cytokines (IFN-γ, TNF-α), soluble death ligands [sFasL, TNF-related apoptosis-inducing ligand (TRAIL)] and activated T-helper type 1 (Th1) and Th2 cell supernatants. The recombinant eosinophil cationic protein induced SMC necrosis within 1 h. Resting SMC expressed the death receptors TNFR1, TNFR2, Fas, TRAILR1, TRAILR2 and membrane FasL as a death-inducing ligand. IFN-γ and TNF-α up-regulated TNFR1, TNFR2, Fas and membrane FasL on SMC. TNF-α up-regulated TRAILR1 and TRAILR2; sFasL up-regulated TNFR2. The intracellular caspase-3 activation in SMC was significantly increased by IFN-γ, sFasL, TRAIL, Th1 and Th2 cell supernatants. Increased expression of TRAIL in asthmatics, but not in non-asthmatic individuals was demonstrated in situ . The apoptosis receptors TRAILR1 and TRAILR2 were expressed in SMC and epithelial cells both in healthy and asthmatic biopsies. Prominent apoptosis of SMC was observed in fatal asthma, but not intermittent asthma biopses.
Conclusion The demonstration of bronchial SMC death both by apoptosis and necrosis indicates the essential role of T cells and eosinophils in the bronchial tissue injury particularly in the severe asthma. 相似文献
202.
Jirka Peschek Nathalie Braun Titus M. Franzmann Yannis Georgalis Martin Haslbeck Sevil Weinkauf Johannes Buchner 《Proceedings of the National Academy of Sciences of the United States of America》2009,106(32):13272-13277
α-Crystallins are molecular chaperones that protect vertebrate eye lens proteins from detrimental protein aggregation. αB-Crystallin, 1 of the 2 α-crystallin isoforms, is also associated with myopathies and neuropathological diseases. Despite the importance of α-crystallins in protein homeostasis, only little is known about their quaternary structures because of their seemingly polydisperse nature. Here, we analyzed the structures of recombinant α-crystallins using biophysical methods. In contrast to previous reports, we show that αB-crystallin assembles into defined oligomers consisting of 24 subunits. The 3-dimensional (3D) reconstruction of αB-crystallin by electron microscopy reveals a sphere-like structure with large openings to the interior of the protein. αA-Crystallin forms, in addition to complexes of 24 subunits, also smaller oligomers and large clusters consisting of individual oligomers. This propensity might explain the previously reported polydisperse nature of α-crystallin. 相似文献
203.
Hakan Cangul Neil V. Morgan Julia R. Forman Halil Saglam Zehra Aycan Tahsin Yakut Tuna Gulten Omer Tarim Ece Bober Yasar Cesur Gail A. Kirby Shanaz Pasha Mutlu Karkucak Erdal Eren Semra Cetinkaya Veysel Bas Korcan Demir Sevil A. Yuca Esther Meyer Michaela Kendall Wolfgang Hogler Timothy G. Barrett Eamonn R. Maher 《Clinical endocrinology》2010,73(5):671-677
Objective Nonsyndromic autosomal recessively inherited nongoitrous congenital hypothyroidism (CHNG) can be caused by mutations in TSHR, PAX8, TSHB and NKX2‐5. We aimed to investigate mutational frequencies of these genes and genotype/phenotype correlations in consanguineous families with CHNG. Design Because consanguinity in individuals with a presumptive genetic condition is often an indicator of an autosomal recessive inheritance and allows firmer correlations to be established between genotype and phenotype, we planned to execute our study in consanguineous families. Patients Hundred and thirty‐nine children with CHNG phenotype born to consanguineous families. Measurements First, we investigated cases for evidence of linkage to the four known CHNG genes by microsatellite marker analysis. Mutation analysis by direct sequencing was then performed in those cases in whom linkage to the relevant candidate gene could not be excluded. In addition, in silico analysis of the predicted structural effects of TSHR mutations was performed and related to the mutation‐specific disease phenotype. Results Homozygous germline TSHR mutations were detected in six families (5%), but no mutations were detected in PAX8, TSHB and NKX2‐5. Four of TSHR mutations had not previously been described. Genotype–phenotype correlations were established and found to be related to the predicted structural effects of the mutations. Conclusions Known causative genes account for the development of CHNG only in a minority of cases, and our cohort should provide a powerful resource to identify novel causative genes and to delineate the extent of locus heterogeneity in autosomal recessively inherited CHNG. 相似文献
204.
I Erturan PY Basak O Ozturk AM Ceyhan VB Akkaya 《Journal of the European Academy of Dermatology and Venereology》2009,23(12):1414-1418
Background Behcet's disease (BD) is a chronic, inflammatory, multisystem vasculitic disorder. There is no reliable laboratory marker that indicates disease activity. Neopterin is an immunological marker of cellular immune activation, which is secreted by monocytes/macrophages as a result of interferon-gamma (IFN-γ) secretion by activated T lymphocytes.
Objective We aimed to investigate serum and urine neopterin levels in BD patients.
Methods Forty-five patients who were diagnosed according to the criteria of the International Study Group for BD and 45 age- and sex-matched healthy controls were enrolled in the study. Disease activity was considered by clinical findings. Serum and urine neopterin levels and serum IFN-γ levels were measured.
Results The mean values of serum and urine neopterin levels were 12.68 ± 4.87 nmol/L and 167.53 ± 148.73 µmol/mol creatinine, respectively, in BD patients ( P = 0.000 and P = 0.008, respectively), which were statistically significantly different from the control group. However, there was no significant statistical difference between serum and urine neopterin levels of the clinically active and inactive patients. It was also found that the mean value of serum IFN-γ levels was higher in healthy controls than in BD patients ( P = 0.000).
Conclusions We conclude that serum and urinary neopterin measurement can not be used as a reliable laboratory marker as the BD patients' serum and urinary neopterin levels do not increase in the active stage even though these levels increase when compared to healthy controls. 相似文献
Objective We aimed to investigate serum and urine neopterin levels in BD patients.
Methods Forty-five patients who were diagnosed according to the criteria of the International Study Group for BD and 45 age- and sex-matched healthy controls were enrolled in the study. Disease activity was considered by clinical findings. Serum and urine neopterin levels and serum IFN-γ levels were measured.
Results The mean values of serum and urine neopterin levels were 12.68 ± 4.87 nmol/L and 167.53 ± 148.73 µmol/mol creatinine, respectively, in BD patients ( P = 0.000 and P = 0.008, respectively), which were statistically significantly different from the control group. However, there was no significant statistical difference between serum and urine neopterin levels of the clinically active and inactive patients. It was also found that the mean value of serum IFN-γ levels was higher in healthy controls than in BD patients ( P = 0.000).
Conclusions We conclude that serum and urinary neopterin measurement can not be used as a reliable laboratory marker as the BD patients' serum and urinary neopterin levels do not increase in the active stage even though these levels increase when compared to healthy controls. 相似文献
205.
Kiter E Celikbas E Akkaya S Demirkan F Kiliç BA 《Journal of the American Podiatric Medical Association》2006,96(4):293-296
In a prospective randomized study of plantar heel pain, 44 patients were treated with injection of 1 mL of 2% prilocaine using the peppering technique, 1 mL of 2% prilocaine combined with 2 mL of autologous blood, or 1 mL of 2% prilocaine mixed with 40 mg of methylprednisolone acetate. At 6-month follow-up, clinical improvement was evaluated by using a 10-cm visual analog scale and the rearfoot score of the American Orthopaedic Foot and Ankle Society. Results were analyzed using sample t-tests within groups and repeated-measures analyses of variance between groups. Mean +/- SD visual analog scale scores in the peppering technique, autologous blood injection, and corticosteroid injection groups improved from 6.4 +/- 1.1, 7.6 +/- 1.3, and 7.28 +/- 1.2 to 2.0 +/- 2.2 (P < .001), 2.4 +/- 1.8 (P < .001), and 2.57 +/- 2.9 (P < .001), respectively. Mean +/- SD rearfoot scores in the same groups improved from 64.1 +/- 15.1, 71.6 +/- 1, and 65.7 +/- 12.7 to 78.2 +/- 12.4 (P = .018), 80.9 +/- 13.9 (P = .025), and 80.07 +/- 17.5 (P = .030), respectively. There were no statistically significant differences among the groups. Good outcomes have been documented using the peppering technique and autologous blood injection for the treatment of lateral epicondylitis. Although the curative mechanisms of both injection modalities are based on a hypothesis, they seem to be good alternatives to corticosteroid injection for the treatment of plantar heel pain. 相似文献
206.
Kalfoglou EA Faikoglu R Ozcan S Petridis G Yükseloglu H Atasoy S 《Oncology reports》2006,16(1):203-206
Malpractice in breast cancer can be seen as false-negative or false-positive findings which may result in either late or incorrect therapies. Biopsy material can be unintentionally interchanged, leading to incorrect treatment, and psychological damage to the patient. There is an obvious need for individualization of the tissue samples in such cases. In this study we used a multidisciplinary approach to integrate DNA technology that has been standardized and used in forensic science for other purposes, mainly to prove malpractice that has been the result of interchanging tissue samples in breast cancer. The main focus of the study was to evaluate the applicability of the technique, therefore we studied the samples of a 58-year-old female for whom the result of pathological analysis was reported as 'invasive ductal carcinoma'. The patient was surgically treated by a modified mastectomy technique and referred for chemotherapy. Prior to chemotherapy we found that the tissue samples analyzed did not belong to the patient in question. We used a battery of 15 polymorphic STR loci to identify the sample and we had strong evidence for exclusion of the patient. The analysis was done on both blood and buccal swab of the patient and on the tissue sample. We concluded that the technique is applicable and useful; however care should be taken in the interpretation of the results because the mutations in the tumoral tissues are very well known. Therefore, the maximum of informative loci should be studied and loss of heterozygosity should always be considered. We should also have in mind the possibility of intentional interchange which gives the results value in medico-legal investigations. 相似文献
207.
Argon A Basaran M Yaman F Dizdar Y Sakar B Camlica H Bavbek SE Ozger H Darendeliler E Onat H 《Japanese journal of clinical oncology》2004,34(11):667-672
BACKGROUND: Older age and axial location of Ewing's sarcoma have been reported as unfavorable prognostic factors. METHODS: The records of patients older than 15 years with the Ewing's family of tumors were reviewed retrospectively. After the induction chemotherapy consisting of alternating vincristine, adriablastin, cyclophosphamide (VAC) and etoposide, ifosfamide with mesna protection (IE), a local treatment modality was chosen based on tumor and patient characteristics. RESULTS: Twenty-five patients with a median age of 19 years were evaluated. Median follow-up was 26 months (range 4-58). Seventeen patients (68%) had died. In univariate analysis, factors predictive of shorter survival were the patients presenting with metastatic disease, with the primary tumor located at the pelvis, those who never achieved complete response to chemotherapy and those who had chemotherapy for <12 months. Only a negative link with pelvic location was observed in multivariate analysis [risk ratio 7.5; 95% confidence interval (CI) 1.52-37.06; P = 0.0134]. Median progression-free survival (PFS) and overall survival (OS) were 10 months (95% CI 6.2-13.8) and 14 months (95% CI 9.3-18.7), respectively. Cumulative 2-year PFS and OS were 19.0% (95% CI, SD +/-8.4) and 32.7% (95% CI, SD +/-9.8), respectively. CONCLUSIONS: The prognosis of patients with axial Ewing's sarcoma is dismal despite an intensive, multimodality approach including multiagent, alternating chemotherapy, surgery and/or radiotherapy. A more aggressive approach should be considered for this group of Ewing's sarcoma patients. 相似文献
208.
Pulmonary alveolar microlithiasis (PAM) is a rare disease of unknown etiology characterized by accumulation of calcific concretions in the alveolar spaces. The paper reports a case of PAM in a 56-year-old male. The patient had persistent dry cough, and gradually progressive dyspnea on exertion. The diagnosis was established on the basis of roentgenography and confirmed by the sputum and transbronchial biopsy findings. Scintigraphy revealed the absence of Tc-99m methylenediphosphonate uptake of lungs. Familial occurrence was not observed. Chest roentgenogram, pulmonary function, and clinical status of the patient have remained stable for 41 months. Radiological and clinical follow-up of the disease continues. 相似文献
209.
Kumral A Tugyan K Gonenc S Genc K Genc S Sonmez U Yilmaz O Duman N Uysal N Ozkan H 《Brain research. Developmental brain research》2005,160(2):146-156
The developing central nervous system is extremely sensitive to ethanol, with well-defined temporal periods of vulnerability. Recent studies have shown that administration of ethanol to infant rats during the synaptogenesis period triggers extensive apoptotic neurodegeneration throughout many regions of the developing brain. Furthermore, acute ethanol administration produces lipid peroxidation in the brain as an indicator of oxidative stress. In recent years, it has been shown that erythropoietin (EPO) has a critical role in the development, maintenance, protection, and repair of the nervous system. In the present study, we investigated the effect of EPO against ethanol-induced neurodegeneration and oxidative stress in the developing C57BL/6 mouse brain. Seven-day-old C57BL/6 mice were divided into three groups: control group, saline-treated group, EPO-treated group. Ethanol was administered to mice at a dosage of 2.5 g/kg for two times with a 2-h interval. Recombinant human EPO (rhEPO) was given 1000 U/kg. Twenty-four hours after the first dose of ethanol, all the animals were killed. Neuronal cell death, apoptosis, thiobarbituric acid substance (TBARS) levels, superoxide dismutase (SOD), and glutathione peroxidase (Gpx) enzymes activities were evaluated. Histopathological evaluation demonstrated that EPO significantly diminished apoptosis in the cerebellum, prefrontal cortex, and hippocampus and also spared hippocampal CA1, CA2, and CA3 neurons. Simultaneous administration of EPO along with ethanol attenuated the lipid peroxidation process and restored the levels of antioxidants. Regarding the wide use of erythropoietin in premature newborns, this agent may be potentially beneficial in treating ethanol-induced brain injury in the perinatal period. 相似文献
210.
Akkaya OF Sahin HA Senel A Ertaş B Kinay K Onar MK 《Clinical neurology and neurosurgery》2005,107(3):246-248
Brain stem masses may mimic Myasthenia gravis (MG), clinically and electrophysiologically. We present a 38 year-old female patient with a brain stem mass, who has clinical features similar with MG, and revealed a decremental response to repetitive nerve stimulation. Brain stem mass was removed by surgery. In the postoperative period, her complaints were regressed. Control repetitive nerve stimulation examination was normal. 相似文献