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31.
BACKGROUND: Adolescent-onset and adult-onset esthesioneuroblastoma is a rare disease and is considered incurable. In many patients, local resection and radiation are chosen as clinical therapy with or without chemotherapy. It was reported previously that local resection and radiotherapy led to temporary remission and, in many patients, recurrent disease. Although combination with chemotherapy has been regarded as promising, an effective regimen has not been established. In the current study, the authors investigated the effect and tolerability of the combination of chemotherapy, radiotherapy, and peripheral blood stem cell transplantation (PBSCT). METHODS: The study population included 12 patients with adolescent-onset and adult-onset esthesioneuroblastoma classified as Kadish Stage A-D. The patients received two cycles of combination chemotherapy, which consisted of cyclophosphamide, doxorubicin, and vincristine (CAD) with continuous-infusion cisplatin and etoposide (CVP). This was combined with radiotherapy with or without PBSCT. RESULTS: Nine of 12 patients (75%) obtained more than a partial response after only 2 cycles of chemotherapy. After radiation with or without PBSCT, six patients obtained a complete remission (CR). The longest survival was > 3 years. All patients who underwent PBSCT obtained a CR. The most severe side effects were loss of sodium and potassium induced by cisplatin-related renal tubular distress. Those abnormalities were temporary, and all patients recovered. CONCLUSIONS: The chemotherapy regimen with CADO and CVP does not require continuation for a long time and is very effective and tolerable for patients with adolescent-onset and adult-onset esthesioneuroblastoma. The combination with radiotherapy and PBSCT may lead to a CR without facial disfigurement. In this report, the authors discuss the feasibility and efficacy of this multidisciplinary approach.  相似文献   
32.
In the present study, the permeation characteristics of a hydrophilic basic compound (HBC) in a bio-mimetic parallel artificial membrane permeability assay (bio-mimetic PAMPA) were investigated in detail. The bio-mimetic PAMPA membrane was constructed on a hydrophobic filter by impregnating a lipid solution consisting of phosphatidylcholine (0.8%, w/w), phosphatidylethanolamine (0.8%, w/w), phosphatidylserine (0.2%, w/w), phosphatidylinositol (0.2%, w/w), cholesterol (1.0%, w/w), and 1,7-octadiene (97.0%, w/w). The pH-permeability curve (pH 3-10), the effect of lipid composition, concentration dependency (0.02-2.00 mM), and inhibition by other cationic compounds, were investigated for several HBCs. Ketoprofen and methylchlorpromazine were also employed as an acidic and a quaternary ammonium compound, respectively. At pH 3-6, the permeability of timolol, a HBC, was higher than expected from the pH-partition hypothesis, especially in the PI-containing membrane, whereas the pH-permeability curve of ketoprofen followed the pH-partition hypothesis. Permeation of HBC was saturable and inhibited by basic and quaternary ammonium compounds. Similar results were also found for methylchlorpromazine. The permeation characteristics of HBC observed in the present study are not usually expected in a passive permeation process across an artificial membrane. The participation of facilitated permeation of cationic species was suggested, in addition to a simple passive diffusion of un-dissociated species. Ion pair transport was suggested as a possible permeation mechanism of cationic species. However, further investigation is necessary to clarify the reason for the permeation characteristics of HBC.  相似文献   
33.
In acute-phase Kawasaki disease, neutrophils cause injury to the coronary arterial endothelium through the production of elastase. Previous research has demonstrated the modulation of neutrophil function and kinetics, such as development and maturation, by granulocyte colony-stimulating factor (G-CSF). To examine the correlation between G-CSF and cardiac complications in Kawasaki disease, functional activity of serum G-CSF and cytokines was measured by enzyme-linked immunosorbent assay in 30 patients with acute-phase Kawasaki disease aged 2 months to 5 years. The mean serum G-CSF was higher in the 1st week of Kawasaki disease than during weeks 2 to 4, and G-CSF was significantly higher in patients with coronary artery dilatation (CAL) than in those without. There was no significant difference in the activity of other cytokines studied or white blood cell counts between the patients with CAL. Conclusion: granulocyte colony-stimulating factor is correlated with coronary artery dilatation in acute-phase Kawasaki disease and increased neutrophil function may contribute to the pathogenesis of coronary arterial endothelial injury in these patients.  相似文献   
34.
It has been suggested from frequency analysis that cardiac fibrillation is driven by stable intramural reentry, with wavebreak occurring due to failure of 1:1 propagation. We tested this hypothesis with a combined experimental and theoretical approach. Optical mapping was performed on epicardial, endocardial, and transmural cut surfaces of fibrillating swine ventricles. Wavelets were characterized, the frequency content of optical signals analyzed, and space-time plots (STPs) constructed to detect Wenckebach-like conduction. The findings were compared with simulations in 2D and 3D cardiac tissue using the Luo-Rudy action potential model. The incidence of reentry in the cut transmural surface (11.8% in right ventricle, 14.3% in left ventricle) was similar to that on the endocardial surface (13.1%, P=NS) but greater than on the epicardial surface (7.7%, P<0.01). Frequency spectra of optically recorded membrane voltage were organized into spatial domains with the same dominant frequency, but these domains were nonstationary. In STPs, pseudo-2:1 conduction block was caused by double potentials arising when reentry occurred on the recording site rather than true Wenckebach conduction. The latter was observed in 11 of 166 STPs but did not occur at borders of high-to-low frequency domains. In simulations, similar findings were obtained when action potential duration (APD) restitution slope was steep. Stationary dominant frequency domains with Wenckebach conduction patterns were observed only in the presence of shallow APD restitution slope and marked nonuniform tissue heterogeneity. In conclusion, stable intramural reentry as the engine of fibrillation was not observed. Our findings support the idea that dynamic wavebreak plays a fundamental role in the generation and maintenance of ventricular fibrillation.  相似文献   
35.
The authors report on 2 neonates with irreducible inguinal hernia in whom a Pfannenstiel skin incision followed by lower abdominal midline fasciotomy were used to open the abdomen during emergency operation. By using this approach, the inguinal canal could also be opened and the hernia sac ligated. Bowel resection followed by anastomosis in one case and appendectomy in the other case could be performed safely intraabdominally because of the better exposure provided by using our approach compared with an inguinal incision alone. A Pfannenstiel incision followed by a midline fasciotomy decreases the risks associated with surgical intervention by enhancing exposure and contributing to good outcome by improving wound cosmesis.  相似文献   
36.
Gene therapy for breast cancer   总被引:6,自引:0,他引:6  
Breast cancer is sensitive to chemotherapy and endocrine therapy, but the prognosis of advanced or relapsed breast cancer is unsatisfactory. Gene therapy is promising as another useful therapeutic approach for advanced breast cancer. Strategies of gene therapy for breast cancer in ongoing clinical protocols can be divided into four: (1) suppression of oncogenes or transduction of tumor suppressors; (2) enhancement of immunological response to cancer cells; (3) transduction of suicide genes; and (4) protection of bone marrow using drug resistance genes. We have started a clinical study of gene therapy for breast cancer using multidrug resistance gene (MDR1), in which advanced or relapsed breast cancer patients received high dose chemotherapy and autologous peripheral blood stem cell transplantation (PBSCT) with MDR1-transduced hemopoietic cells, and then were treated with docetaxel. Two patients have been treated so far, and in vivo enrichment of MDR1-transduced cells with docetaxel treatment after PBSCT was seen in both cases. Both patients are in complete remission and have no apparent adverse effect from MDR1 gene transduction.  相似文献   
37.
Transcanal endoscopic ear surgery (TEES) will become a very useful therapeutic option. A perilymphatic fistula (PLF) is defined as sudden sensorineural hearing loss and/or vertigo caused by leakage of the perilymph through a fistula from the oval window and/or round window. We report a case of PLF after electric acoustic stimulation (EAS), a kind of cochlear implant, successfully treated by TEES. A 38-year-old man presented to our hospital with vertigo and hearing loss (HL). His vertigo was induced by Valsalva maneuvers. Eight months ago, he underwent EAS for his right ear for congenital sensorineural HL. Although he maintained his hearing level after EAS, his pure tone audiogram this time showed deterioration of hearing at low frequencies in his right ear. A diagnosis of right PLF was made. After confirming the non-effectiveness of oral prednisolone treatment, PLF repair surgery to patch the oval and round windows by TEES was performed. His vertigo did not recur after the surgery. To the best of our knowledge, this is the first report of PLF repair surgery by TEES without a microscope. The wide-field view of the middle ear by TEES was useful to prevent electrode damage in a PLF patient with a cochlear implant.  相似文献   
38.
α-Dystroglycan (α-DG) represents a highly glycosylated cell surface molecule that is expressed in the epithelial cell-basement membrane (BM) interface and plays an essential role in epithelium development and tissue organization. The α-DG–mediated epithelial cell-BM interaction is often impaired in invasive carcinomas, yet roles and underlying mechanisms of such an impaired interaction in tumor progression remain unclear. We report here a suppressor function of laminin-binding glycans on α-DG in tumor progression. In aggressive prostate and breast carcinoma cell lines, laminin-binding glycans are dramatically decreased, although the amount of α-DG and β-dystroglycan is maintained. The decrease of laminin-binding glycans and consequent increased cell migration were associated with the decreased expression of β3-N-acetylglucosaminyltransferase-1 (β3GnT1). Forced expression of β3GnT1 in aggressive cancer cells restored the laminin-binding glycans and decreased tumor formation. β3GnT1 was found to be required for laminin-binding glycan synthesis through formation of a complex with LARGE, thus regulating the function of LARGE. Interaction of the laminin-binding glycans with laminin and other adhesive molecules in BM attenuates tumor cell migratory potential by antagonizing ERK/AKT phosphorylation induced by the components in the ECM. These results identify a previously undescribed role of carbohydrate-dependent cell-BM interaction in tumor suppression and its control by β3GnT1 and LARGE.  相似文献   
39.
In this study, we tested the effect of donor fasting with or without the use of an essential fatty acids deficiency (EFAD) diet in the recipient using rat heart, pancreas, and liver transplant models. We then compared the survivals, tumor necrosis factor alpha (TNF-α) response, and white cell accumulation in rats in order to clarify the mechanisms of the beneficial effect of donor fasting and recipient EFAD. It was found that when the grafts were obtained from fasted donors and then transplanted into fed recipients, the survival rate was significantly higher for all three grafts than for those obtained from fed rats and transplanted into fed rats. The best survival was seen for pancreas grafts obtained from fasted donors and then transplanted into EFAD recipients. TNF-α secretion was significantly suppressed in both fasted and EFAD rats, and both the total cell count and neutrophil count were suppressed in EFAD rats. These results clearly indicate that in addition to liver grafts, both heart and pancreas grafts obtained from fasted animals are more tolerant to warm ischemic injury. Furthermore, the combination of donor fasting and recipient EFAD acts synergistically to inhibit the post-transplantation inflammatory reaction (through decreased TNF-α secretion and white cell accumulation), thus resulting in an improved survival.  相似文献   
40.
Lentiviral vectors (LVs), which preferentially target nondividing cells, such as neurons, are promising tools for gene therapy. However, these vectors are still unsuitable as they result in insertional mutagenesis. It is therefore essential to prevent insertional mutagenesis if these vectors are to be adopted for safe next-generation clinical applications. In order to establish safe genetic therapy with LVs, we focused on the integrase recognition sequence (att) in the long terminal repeat (LTR), which is localized at the edge of the preintegrated viral DNA. We generated LTR-modified LVs (LMLVs), by altering the conserved sequences located just before the cleavage site; this alteration prevented the integration of viral DNA into the host genome. In this study, the LMLVs significantly decreased the LV-mediated transgene expression in HeLa cells compared to the control, i.e., wild-type LTR LVs; this supposedly occurred because integration was prevented. In addition, LMLVs exhibited gene expression in vivo when they were injected into the mouse cerebellum. Moreover, quantitative Alu element—mediated polymerase chain reaction (Alu-PCR), which detects integrated viral DNA, revealed that rate of LMLV-suppressed integration was approximately 1/500-fold compared to that in the case of the wild-type LTR LV. These data suggest that LMLVs efficiently prevent integration as well as exhibit LV-mediated gene expression in mouse cerebellar Purkinje cells in vivo.  相似文献   
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