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991.
Increased susceptibility to oxidant injury in hepatocytes from rats with intra-abdominal hypertension 总被引:2,自引:0,他引:2
Hsu YP Chen RJ Fang JF Lin BC Huang TL Cheng ML Chiu DT Tsay PK 《The Journal of trauma》2004,57(3):569-575
BACKGROUND: Intra-abdominal hypertension leads to visceral organ hypoperfusion, and subsequent decompression may cause ischemia-reperfusion, releasing toxic metabolites. This study focuses on the effect of intra-abdominal hypertension on hepatic antioxidant store and the susceptibility of hepatocytes to oxidant injury. METHODS: Sprague-Dawley rats (150-180 g) were acclimatized to an environment for 3 days and then divided into two groups according to challenge based on intra-abdominal pressure (0 and 30 cm H2O for control and experimental groups, respectively). After a 90-minute challenge, the rats underwent immediate laparotomy for decompression; after a further 30 minutes, one fragment of liver from the lingual lobe (>0.1 g) was excised to measure glutathione (GSH) in vivo before portal vein perfusion. After hepatocyte isolation (viability rate > 85%), the cell density was set at 1 x 10/mL for each well. The samples were cultured in an incubator for 12 hours, after which varying concentrations of t-butyl hydroperoxide (TBHP) (0.0, 0.5, 1.0, and 2.0 mmol/L) were added into the wells. After another 5-hour incubation, the total store of intracellular GSH in vitro (GSHVT) and the hepatocyte survival rates were measured for different groups of TBHP challenge using GSH assay and MTT kits. RESULTS: The control and experimental groups consisted of 10 and 8 rats, respectively, that successfully completed the entire experimental procedure. Compared with the control group, the in vivo GSH store was significantly reduced after the intra-abdominal pressure challenge (mean +/- SE, 968.1 +/- 63.5 vs. 1,581.0 +/- 115.3 nmol/g of protein; p = 0.001). After the hepatocyte isolation, the GSHVT stores at various TBHP concentrations in the experimental rats were also similarly and significantly decreased relative to the control animals (894.4 +/- 56.4, 804.2 +/- 118.4, 586.9 +/- 86.6, and 410.2 +/- 87.4 nmol/g of protein vs. 1,282.2 +/- 112.0, 1,156.6 +/- 91.0, 995.2 +/- 92.7, and 866.8 +/- 62.4 nmol/g of protein for TBHPs of 0.0, 0.5, 1.0, and 2.0 mmol/L, respectively; all p < 0.05). Moreover, from photocytometry, the hepatocyte survival rates were significantly reduced for the experimental rats compared with the control animals after challenge with various TBHP concentrations (survival was 100%, 91.1%, 81.3%, and 72.8% vs. 100%, 99.2%, 95.0%, and 88.2%, respectively, for TBHPs of 0.0, 0.5, 1.0, and 2.0 mmol/L; p < 0.05 for the last two). CONCLUSION: This animal study demonstrated that intra-abdominal hypertension and subsequent decompression deplete the total in vivo GSH store in rat livers, probably via the mechanism of ischemia-reperfusion injury, and the GSHVT after hepatocyte isolation, which makes the isolated hepatocytes of rats more susceptible to oxidant challenge. 相似文献
992.
Acute renal failure after cadaveric related liver transplantation 总被引:21,自引:0,他引:21
Chuang FR Lin CC Wang PH Cheng YF Hsu KT Chen YS Lee CH Chen CL 《Transplantation proceedings》2004,36(8):2328-2330
Acute renal failure (ARF) is a frequent medical complication after liver transplantation (LT). We analyzed cadaveric related liver transplant recipients who had developed ARF early in the postoperative course. Between January 1982 and August 2003, a total of 67 patients underwent cadaveric related LT. Their mean age was 28.64 years at LT. The 67 recipients had the following indications: biliary atresia (n = 17), Wilson's disease (n = 15), hepatitis B-related liver cirrhosis (n = 14), hepatitis C-related liver cirrhosis (n = 4), primary biliary cirrhosis (n = 4), hepatitis B-related liver cirrhosis with hepatoma (n = 3), hepatitis C-related liver cirrhosis with hepatoma (n = 2), Budd-Chiari syndrome (n = 2), neonatal hepatitis (n = 1), choledochus cyst (n = 1), autoimmune cirrhosis (n = 1), neuroendocrine tumor (n = 1), and hemangioendothelioma (n = 1). Forty-nine patients received cyclosporine (CsA), azathioprine, and steroids and 18, a combination with tacrolimus (FK506). Eight (11.94%) patients developed ARF at a mean time of 17.25 days after LT. The mean peak serum creatinine was 2.24 mg%. Four of these patients had a diagnosis of hepatitis B-related liver cirrhosis; two, hepatitis C-related liver cirrhosis; one, primary biliary cirrhosis; and one, hepatitis B-related liver cirrhosis with hepatoma. The ARF etiology was multifactorial for the majority of patients. Eight ARF patients had a history of liver cirrhosis, which may be a risk factor for intraoperative ARF. ARF treatment included fluid replacement, decreased or altered immunosuppressive agents, avoiding exposure to nephrotoxic drugs, and adjusting antibiotic dosages. The majority of patients returned to normal renal function at 1 to 3 weeks after the diagnosis of ARF. No patient required dialysis and/or experienced a mortality. We conclude that the incidence of ARF is relatively low and with good outcomes. ARF etiology was multifactorial for the majority of patients, but eight patients had a history of liver cirrhosis, which may be a risk factor for intraoperative ARF. We suggest that in the early postoperative period of LT cases diagnosis and treatment of ARF are important. 相似文献
993.
The significance of transarterial embolization for advanced hepatocellular carcinoma in liver transplantation 总被引:4,自引:0,他引:4
Sun PL Chen CL Hsu SL Huang TL Chen TY Chen YS Tsang LC Cheng YF 《Transplantation proceedings》2004,36(8):2295-2296
INTRODUCTION: Transarterial embolization (TAE) is the treatment of choice for advanced HCC to control or even induce tumor shrinkage. The aim of this study was to evaluate the effect of pretransplantation TAE for treatment of advanced HCC. MATERIAL AND METHODS: From 1996 to 2002, we studied 12 cirrhotic patients with HCC, including six who met and six who exceeded the Milan criteria. All patients had sufficient hepatic function to undergo TAE. Liver transplantations were performed subsequently and they were followed prospectively for a median of 22 months (range = 12 to 53 months). RESULTS: The explanted livers from the 12 patients who had undergone TAE were noted to have extensive tumor necrosis. The pathological specimens at LT showed downstaging of the HCC, which allowed those six patients to meet the Milan criteria. The overall 1- and 2-year survival rates were 92% and 73%, respectively. The overall 1- and 2-year disease-free survival rates were 92% and 73%, respectively. One death unrelated to liver disease at 2 years after LT was noted in the downgraded group. One patient of the initially eligible group developed lung metastasis at 6 months and died at 12 months after LT. CONCLUSION: TAE is effective to downstage advanced HCC and reduce the dropout rate on the LT waiting list. Pre-LT TAE may be considered as a better therapeutic strategy for patients with advanced HCC. 相似文献
994.
Yang S Lin WC Chang HK Hsu JM Lin WR Chow YC Tsai WK Lee TA Lo KY Chow K Chen M 《Urologia internationalis》2004,73(3):258-261
INTRODUCTION: This randomized prospective study was conducted to compare the efficacy and safety of the Gyrus Plasmasect loop bipolar transurethral resection of prostate (TURP) and conventional monopolar TURP in the treatment of benign prostatic hyperplasia (BPH). MATERIALS AND METHODS: A total of 117 men were enrolled in this study. Fifty-eight patients underwent Gyrus Plasmasect TURP and 59 patients underwent monopolar TURP. They were followed up for 3 months after surgery. RESULTS: Significant improvements were seen postoperatively in both the Gyrus and monopolar groups in terms of prostatic volume, International Prostate Symptom Score, quality of life score, peak flow rate, and post-void residual urine volume. However, the degree of improvement was not statistically different between the 2 groups. Significantly less blood loss, shorter postoperative catheterization time and length of hospital stay were seen in the Gyrus group. CONCLUSIONS: Gyrus Plasmasect TURP yielded comparable results to monopolar TURP; however, this is only a preliminary study and follow-up is necessary to assess its long-term efficacy. 相似文献
995.
Expansion of quasispecies diversity but no evidence for adaptive evolution of SHIV during rapid serial transfers among seronegative macaques 总被引:5,自引:0,他引:5
Four successive, rapid serial passages of the nonpathogenic, CCR5-tropic simian-human immunodeficiency virus SHIV(SF162) in rhesus macaques resulted in an increase in acute plasma viremia with each passage and the emergence of a pathogenic isolate SHIV(SF162P3) in one of the passage three transfer animals (macaque T353). To explore the mechanism(s) underlying increased virulence of SHIV(SF162) upon in vivo passage, the evolution of the HIV-1 envelope gene was characterized in plasma and PBMC samples obtained from animals before (week 1) and after (week 3) the time of virus transfer. We found no evidence in support of adaptive evolution of the HIV gp120 during rapid serial passage; however, the animals which later received passage virus had more diverse quasispecies. SHIV(SF162P3)-like gp120 sequences were first detected in macaque T353 at week 6, after seroconversion. These sequence changes increased in frequency and number at later time points. The first sequence change conferred neutralization escape but not an increase in viral infectivity that could account for the apparent increase in replicative capacity of the later passage viruses. Collectively, our data argue against any host-specific adaptation of the HIV-1 envelope gp120 as the basis for the generation of more aggressive SHIV variants during rapid serial transfers in seronegative macaques, and support the model of quasispecies diversity as a predictor of pathogenesis. Envelope sequence changes accumulate principally in response to immune pressure exerted by the host, generating viral variants that can persist in the presence of a strong host immune response. 相似文献
996.
Hsu CH Lin SS Liu FL Su WC Yeh SD 《The Journal of allergy and clinical immunology》2004,113(6):268-1085
BACKGROUND: Sublingual-swallow immunotherapy in house dust mite-related asthma has a good safety profile and improves respiratory function and bronchial hyperreactivity. Zucchini yellow mosaic virus (ZYMV) is envisaged as a promising viral vector for expressing large quantity of foreign proteins in cucurbit species. OBJECTIVE: We sought to investigate whether oral feeding of dust mite allergen expressed by ZYMV in a cucurbit species can suppress allergen-induced inflammation and IgE synthesis. METHODS: An infectious plant virus clone, p35SZYMV2-26, that contains the full-length cDNA to the genomic RNA of a Taiwan isolate of ZYMV, driven by the cauliflower mosaic virus 35S promoter, was engineered as an in vivo viral vector to express Dermatophagoides pteronyssinus group 5 allergen (Der p 5) in cucurbit species. Female BALB/c mice were intraperitoneally sensitized with Escherichia coli bacteria-expressed Der p 5 and orally treated with the virus-expressed Der p 5 (vDer p 5) extracted from the recombinant virus-infected squash plants. Der p 5-specific immunoglobulins were measured by ELISA, and bronchoalveolar lavage assays were used to measure airway inflammation. RESULTS: Infectivity assays and immunoblotting revealed that large quantities of free-form vDer p 5 are produced in the recombinant virus-infected squash plants. The recombinant virus carried and expressed the Der p 5 allergen in squash plants for at least 1 year after numerous passages. In animal tests, squash extract containing vDer p 5 inhibited Der p 5-specific IgE synthesis and airway inflammation. CONCLUSION: Our results suggest that oral feeding with allergen produced by the plant viral vector provides a novel approach for the therapy of allergic asthma. 相似文献
997.
Chang YC Hsu TL Lin HH Chio CC Chiu AW Chen NJ Lin CH Hsieh SL 《Journal of leukocyte biology》2004,75(3):486-494
Decoy receptor 3 (DcR3) is a soluble receptor of the tumor necrosis factor receptor superfamily and is readily detected in certain cancer patients. Recently, we demonstrated that DcR3.Fc-treated dendritic cells skew T cell responses to a T helper cell type 2 phenotype. In this study, we further asked its ability to modulate CD14+ monocyte differentiation into macrophages induced by macrophage-colony stimulating factor in vitro. We found that DcR3.Fc was able to modulate the expression of several macrophage markers, including CD14, CD16, CD64, and human leukocyte antigen-DR. In contrast, the expression of CD11c, CD36, CD68, and CD206 (mannose receptor) was not affected in the in vitro culture system. Moreover, phagocytic activity toward immune complexes and apoptotic bodies as well as the production of free radicals and proinflammatory cytokines in response to lipopolysaccharide were impaired in DcR3.Fc-treated monocyte-derived macrophages. This suggests that DcR3.Fc might have potent, suppressive effects to down-regulate the host-immune system. 相似文献
998.
Li CC Qian ZR Hirokawa M Sano T Pan CC Hsu CY Yang AH Chiang H 《APMIS : acta pathologica, microbiologica, et immunologica Scandinavica》2004,112(6):390-398
Female adnexal tumor of probable Wolffian origin (FATWO) is a rare entity which is believed to originate from mesonephric (Wolffian) remnants on the basis of its location where the remnants are abundant. Its behavior is usually indolent, although some cases can recur or metastasize. The authors present the clinicopathological features of two cases of FATWO arising in the broad ligament, and focus on the expression of adhesion molecules and proliferative marker. Mesonephric duct remnants are also examined in an attempt to elucidate the histogenesis of FATWOs. The two FATWOs were well-circumscribed solid masses arising in the leaves of the broad ligament and histological examination revealed a mixture of cysts and tubules imparting a sieve-like pattern and mucin-negative eosinophilic secretion within these tubules. Immunohistochemically, the tumors showed the expression of cytokeratin 7 and 20, high-molecular-weight cytokeratin, and calretinin, which closely resembled that of the mesonephric duct remnants. Regarding CK 20, CD 10, EMA, S-100 protein, and vimentin their expression was in part not identical with previous studies. E-cadherin, alpha and beta-catenin were strongly expressed along the cell membrane of the tumor cells. The Ki-67 labeling index of FATWO was 0% and 3.2% in each case. The preservation of the E-cadherin-catenin complex and low Ki-67 labeling index could explain the indolent behavior and low malignant potential of this tumor. 相似文献
999.
Based on granular computing methodology, we propose two criteria to quantitatively measure privacy invasion. The total cost criterion measures the effort needed for a data recipient to find private information. The average benefit criterion measures the benefit a data recipient obtains when he received the released data. These two criteria remedy the inadequacy of the deterministic privacy formulation proposed in Proceedings of Asia Pacific Medical Informatics Conference, 2000; Int J Med Inform 2003;71:17-23. Granular computing methodology provides a unified framework for these quantitative measurements and previous bin size and logical approaches. These two new criteria are implemented in a prototype system Cellsecu 2.0. Preliminary system performance evaluation is conducted and reviewed. 相似文献
1000.
Association analysis between Tourette's syndrome and dopamine D1 receptor gene in Taiwanese children
OBJECTIVE: Recent research suggests that Tourette's syndrome (TS) may result from a defect in the dopamine system. The dopamine 1 receptor (DRD1) gene is a candidate gene in the study of the etiology of neuropsychiatric diseases that may involve dopaminergic abnormalities. We sought to test the hypothesis that the DRD1 gene might play a role in TS. METHODS: By performing an association study, we collected an independent sample of patients from the midland region of Taiwan and investigated whether DRD1 gene polymorphisms can be used as markers of susceptibility to TS. A total of 148 children with TS and 83 normal control subjects were included in the study. A polymerase chain reaction was used to identify the A/G polymorphism of the DRD1 gene. Genotypes and allelic frequencies for the DRD1 gene polymorphisms in both groups were compared. RESULTS: The results showed that genotypes and allelic frequencies for the DRD1 gene polymorphisms in both groups were not significantly different. CONCLUSION: These data suggest that DRD1 gene may not be a useful marker for prediction of the susceptibility of TS. 相似文献