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121.
Although the antigen expression patterns of childhood acute lymphoblastic leukemia (ALL) are well known, little attention has been given to standardizing the diagnostic and classification criteria. We retrospectively analyzed the flow cytometric data from a large study of antigen expression in 1,774 children with newly diagnosed ALL in JPLSG. T- and B-lineage ALL accounted for 13 and 87% of childhood ALL cases, respectively. Cytoplasmic CD3 and CD7 antigens were positive in all T-ALL cases. More than 80% of T-ALL cases expressed CD2, CD5 and TdT. In B-lineage ALL, the frequencies of early pre-B, pre-B, transitional pre-B and B-ALL were 81, 15.5, 0.6 and 2.9%, respectively. More than 90% of early pre-B ALL cases expressed CD19, CD79a, CD22, CD10 and TdT. CD34 was expressed in three-fourths of early pre-B ALL cases. The frequencies of TdT and CD34 expression were lower in pre-B ALL than in early pre-B ALL. B-ALL showed less frequent expression of CD22, CD10, CD34 and TdT than other B-lineage ALL cases. Expression of CD13 and CD33, aberrant myeloid antigens, was significantly more frequently associated with B-lineage ALL than with T-ALL. Based on this retrospective study of antigen expression in 1,774 de novo childhood ALL cases in JPLSG, we propose standardized clinical guidelines for the immunophenotypic criteria for diagnosis and classification of pediatric ALL.  相似文献   
122.
123.
This study investigated whether an intestinal epithelial culture method can be applied to mouse and human esophageal cultures. The esophagi harvested from 1‐day‐old mice and adult humans were maintained in collagen gels. A commercially available culture medium for human embryonic stem cells was used for the human esophageal culture. We discovered that the intestinal epithelial culture method can be successfully applied to both mouse and human esophageal cultures. The long‐term cultured esophageal organoids were rod‐like luminal structures lined with myofibroblasts. We discovered that regeneration of the esophageal mucosal surface can be almost completely achieved in vitro, and the advantage of this method is that organoid cultures may be generated using host‐derived fibroblasts as a niche. This method is a promising tool for mouse and human research in intestinal biology, carcinogenesis, and regenerative medicine.  相似文献   
124.
DU6859a was evaluated for its in vitro and in vivo antibacterial activities in comparison with those of imipenem, meropenem, cefpirome, vancomycin, gentamicin, ciprofloxacin and levofloxacin. DU6859a had activity comparable to that of imipenem against methicillin-susceptible staphylococci and penicillin-susceptible and-resistantStreptococcus pneumoniae, with MICs at which 90% of strains tested are inhibited (MIC90)≤0.063μg/mL. Against methicillin-resistant staphylococci and enterococci, DU6859a was as active as vancomycin and more active than other drugs tested, with MIC90s ranging from 1 to 4 μg/mL. DU6859a was as active as ciprofloxacin and more active than other drugs tested against imipenem-resistantPseudomonas aeruginosa. Differences in activity between DU6859a and reference drugs against ciprofloxacin-resistant and gentamicin-resistantP. aeruginosa were particularly striking. The in vivo efficacy of subcutaneous injections of DU6859a against experimental septicemia, respiratory and pyelonephritic infections caused by gram-positive and-negative bacteria, including methicillin-resistantStaphylococcus aureus and imipenem-resistantP. aeruginosa, reflected its potent in vitro activity.  相似文献   
125.
The striatonigral and olivopontocerebellar systems are known to be vulnerable in multiple system atrophy (MSA), showing neuronal loss, astrogliosis, and alpha-synuclein-immunoreactive inclusions. MSA patients who displayed abundant neuronal cytoplasmic inclusions (NCIs) in the regions other than the striatonigral or olivopontocerebellar system have occasionally been diagnosed with variants of MSA. In this study, we report clinical and pathologic findings of MSA patients characterized by prominent pathologic involvement of the hippocampus. We assessed 146 consecutively autopsied MSA patients. Semi-quantitative analysis of anti-alpha-synuclein immunohistochemistry revealed that 12 of 146 patients (8.2%) had severe NCIs in two or more of the following areas: the hippocampal granule cells, cornu ammonis areas, parahippocampal gyrus, and amygdala. In contrast, the remaining 134 patients did not show severe NCIs in any of these regions. Patients with severe hippocampal involvement showed a higher representation of women (nine women/three men; Fisher's exact test, p = 0.0324), longer disease duration (13.1 ± 5.9 years; Mann–Whitney U-test, p = 0.000157), higher prevalence of cognitive impairment (four patients; Fisher's exact test, p = 0.0222), and lower brain weight (1070.3 ± 168.6 g; Mann–Whitney U-test, p = 0.00911) than other patients. The hippocampal granule cells and cornu ammonis area 1/subiculum almost always showed severe NCIs. The NCIs appeared to be ring-shaped or neurofibrillary tangle-like, fibrous configurations. Three of 12 patients also had dense, round-shaped NCIs that were morphologically similar to pick bodies. The patients with Pick body-like inclusions showed more severe atrophy of the medial temporal lobes and broader spreading of NCIs than those without. Immunohistochemistry for hyperphosphorylated tau and phosphorylated TDP-43 revealed minimal aggregations in the hippocampus of the hippocampal MSA patients. Our observations suggest a pathological variant of MSA that is characterized by severe involvement of hippocampal neurons. This phenotype may reinforce the importance of neuronal alpha-synucleinopathy in the pathogenesis of MSA.  相似文献   
126.

Background

Plasma removal by washing is an effective approach to prevent transfusion reactions by platelet concentrates (PCs). Recently, washed PCs were released by the Japanese Red Cross Society (JRCS).

Materials and methods

This retrospective multicenter study evaluated the efficacy and safety of released washed PCs (RWPCs) between September 2016 and January 2017 in Japan. The RWPCs were prepared by washing leukoreduced apheresis PCs with the platelet additive solution, BRS-A, using automated cell processors.

Results

Clinical data were obtained from 91 patients and 1210 RWPC transfusions at 50 institutions. The median number of RWPC transfusions per patient was 8 (range, 1–91). RWPCs were used in 94.5% of the patients with a history of recurrent or severe transfusion reactions for preventing such reactions. Responses of RWPCs were evaluated as complete response (91.6%), partial response (8.2%), no-change (0.2%), and progression (0%) and overall response was equal across subgroups divided by patients’ profiles. The median corrected count increment (CCI) at 1 and 24?h post-transfusion were 13.5 (range, 1.9–35.4)?×?109/L and 3.5 (range, ?13 to 53.6)?×?109/L, respectively, and median CCI at 24?h was 5.5 (range, ?13 to 53.6)?×?109/L in patients without risk factors associated with platelet transfusion refractoriness. Transfusion reactions to RWPCs were observed in only nine transfusions (0.7%), all of which were mild allergic reactions.

Conclusion

This study demonstrated that RWPCs were effective and safe in patients with a history of transfusion reactions. Further prospective studies on efficacy together with cost-benefit analysis in RWPCs are needed.  相似文献   
127.
Chondroitin sulfate (CS) is an important glycosaminoglycan and is mainly found in the extracellular matrix as CS proteoglycans. In the brain, CS proteoglycans are highly concentrated in perineuronal nets (PNNs), which surround synapses and modulate their functions. To investigate the importance of CS, we produced and precisely examined mice that were deficient in the CS synthesizing enzyme, CSGalNAcT1 (T1KO). Biochemical analysis of T1KO revealed that loss of this enzyme reduced the amount of CS by approximately 50% in various brain regions. The amount of CS in PNNs was also diminished in T1KO compared to wild-type mice, although the amount of a major CS proteoglycan core protein, aggrecan, was not changed. In T1KO, we observed abnormalities in several behavioral tests, including the open-field test, acoustic startle response, and social preference. These results suggest that T1 is important for plasticity, probably due to regulation of CS-dependent PNNs, and that T1KO is a good model for investigation of PNNs.  相似文献   
128.
Solitary Fibrous Tumor in the Retroperitoneal Space: Report of a Case   总被引:2,自引:0,他引:2  
Solitary fibrous tumors (SFTs) are spindle-cell neoplasms originally described in the pleura. It is now known that these tumors can develop in many sites. This report describes the case of a well-circumscribed tumor located around the superior mesenteric artery (SMA), which was initially thought to be either a superior SMA aneurysm, a lymphoma, or a neurogenic tumor. Histological examination demonstrated the tumor to be composed of a cellular proliferation of ovoid to spindle cells with a fine collagenous matrix in the short fascicles. Immunohistochemical staining was strongly positive for CD34 and negative for factor VIII, cytokeratin, desmin, and muscle-specific actin (HHF-35). These findings suggested a diagnosis of SFT in the retroperitoneal space. To our knowledge, this is the first report of an SFT located around the SMA. Based on the above findings, it is important to include SFT in the differential diagnosis of retroperitoneal tumors located around the SMA. Received: August 13, 2001 / Accepted: March 5, 2002 Reprint requests to: M. Kume  相似文献   
129.
HYPOTHESIS: Preoperative administration of methylprednisolone sodium succinate can control surgical stress in patients undergoing hepatic resection. DESIGN: A prospective randomized trial. SETTING: A university hospital department of surgery. PATIENTS: Thirty-three patients who underwent hepatic resection were classified into 2 groups: a control group (n = 16) and a steroid group (n = 17) in which patients were intravenously administered 500 mg of methylprednisolone 2 hours before surgery. MAIN OUTCOME MEASURES: Perioperative levels of interleukin (IL)-6 and IL-10 (serum and peritoneal), immunosuppressive acidic protein, Candida antigen, and other laboratory and clinical variables were measured. RESULTS: Postoperative levels of serum and peritoneal IL-6 and levels of C-reactive protein were significantly lower in the steroid group than in controls. Furthermore, serum and peritoneal IL-10 levels were significantly higher in the steroid group. The total bilirubin value on postoperative day 1 was significantly lower in the steroid group than in controls. Postoperative immunosuppressive acidic protein levels were also significantly lower in the steroid group, as was the positive rate of serum Candida antigen. No differences were found in the incidence of postoperative complications. CONCLUSIONS: Preoperative steroid administration significantly elevated anti-inflammatory cytokine IL-10 levels, suppressed the levels of inflammatory cytokines IL-6 and C-reactive protein, and prevented postoperative elevation of total bilirubin values. Furthermore, postoperative elevation of immunosuppressive acidic protein levels and the positive rate of Candida antigen were suppressed, indicating that the immune response was maintained by preoperative steroid administration.  相似文献   
130.
BACKGROUND: Tacrolimus is a substrate of P-glycoprotein (PGP) encoded by the multidrug resistant (MDR)1 gene (ABCB1). PGP, a multidrug efflux pump, restricts the distribution of tacrolimus in the brain. In this study, we investigate the correlation of ABCB1 gene polymorphism with tacrolimus-induced neurotoxicity in patients after liver transplantation. METHODS: The genotype of 6 patients with neurotoxic events and 11 patients without neurotoxic events was analyzed by polymerase chain reaction (PCR), and 8 mutations were detected. In addition to laboratory findings and patient characteristics, the contribution of mutations in the ABCB1 gene was evaluated with stepwise discriminant function analysis. RESULTS: High tacrolimus concentration, liver dysfunction, and mutation at position 2677 in exon 21 were demonstrated as positive predictors of tacrolimus-induced neurotoxicity. CONCLUSION: It is indicated that blood concentrations, liver function, graft weight, and polymorphism in the ABCB1 gene are important factors in tacrolimus-induced neurotoxicity.  相似文献   
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