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1.
Recent studies have indicated that bone marrow cells can regenerate damaged muscles and that they can adopt phenotypes of other cells by cell fusion. Our direct visualization system gave evidence of massive muscle regeneration by green fluorescent protein (GFP)-labeled CD45+c-Kit+Sca-1+Lin- cells (KSL cells), and we investigated the role of KSL cells in muscle regeneration after transplantation with or without lethal irradiation. In the early phase, GFP signals were clearly observed in all the muscles of only irradiated mice. Transverse cryostat sections showed GFP+myosin+ muscle fibers, along with numerous GFP+ hematopoietic cells in damaged muscle. These phenomena were temporary, and GFP signals had dramatically reduced 30 days after transplantation. After 6 months, GFP+ fibers could hardly be detected, but GFP+c-Met+ mononuclear cells were located beneath the basal lamina where satellite cells usually exist in both conditioned mice. Immunostaining of isolated single fibers revealed GFP+PAX7+, GFP+MyoD+, and GFP+Myf5+ satellite-like cells on the fibers. Single-fiber cultures from these mice showed proliferation of GFP+ fibers. These results indicate two different roles of KSL cells: one leading to regeneration of damaged muscles in the early phase and the other to conversion into satellite cells in the late phase.  相似文献   
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Abstract For many years lactate was considered to be a waste product of glycolysis. Data are accumulating that suggest that lactate is an important energy substrate for neurons during activation. In severe traumatic brain injury (TBI) glutamate release and ischemic cerebral blood flow (CBF) are major factors for a mismatch between energy demand and supply and for neuronal cell death. Although ATP and behavior could be improved by lactate treatment after TBI, no histological correlate nor any linkage to better astrocytic glutamate uptake or CBF as possible mechanisms have been described. We subjected male rats to a controlled cortical impact (CCI; 5?m/sec, 2.5?mm). To study the effects of lactate treatment on lesion volume, glutamate release, and CBF, animals were infused with either NaCl or 100?mM lactate for up to 3?h. The role of endogenous lactate was investigated by inhibiting transport with α-cyano-4-hydroxy-cinnamic acid (4-CIN; 90?mg/kg). Lactate treatment 15?min post-CCI reduced lesion volume from 21.1±2.8?mm(3) to 12.1±1.9?mm(3) at day 2 after CCI. Contusion produced a significant three- to fourfold increase of glutamate in microdialysates, but there was no significant difference between treatments that began 30?min before CCI. In this experiment lesion volume was significantly reduced by lactate at day 7 post-CCI (23.7±4 to 9.3±1-2?mm(3)). CBF increased immediately after CCI and dropped thereafter below baseline in all animals. Lactate infusion 15?min post-CCI elevated CBF for 20?min in 7 of 10 animals, whereas 7 of 8 NaCl-treated animals showed a further CBF decline. Neuroprotection was achieved by lactate treatment following contusion injury, whereas blocking of endogenous lactate transport exerted no adverse effects. Neuroprotection was not achieved by improved glutamate uptake into astrocytes, but was supported by augmented CBF following CCI. Due to its neuroprotective property, lactate might be a beneficial pharmacological treatment for TBI patients.  相似文献   
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We describe a case of gastric aberrant pancreas with acute pancreatitis. Barium meal examination, endoscopic examination and computed tomography of a 32-year-old man with abdominal pain revealed a submucosal tumor, about 3.5 cm in diameter, at the angulus of his stomach. Endoscopic ultrasonography revealed a hypoechoic mass with anechoic capillary areas. His serum amylase level was high at 262 IU/l. Laparoscopy-assisted local resection was carried out. The resected tumor revealed pancreatic tissue with extensive neutrophil infiltration in the gastric wall and fat necrosis in the subserosa. There are few cases of histologically proven acute pancreatitis in gastric aberrant pancreatic tissue.  相似文献   
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We aimed to evaluate the utility of a simplified ultrasonography (US) scoring system, which is desired in daily clinical practice, among patients with rheumatoid arthritis (RA) receiving biological/targeted synthetic disease-modifying antirheumatic drugs (DMARDs).A total of 289 Japanese patients with RA who were started on tumor necrosis factor inhibitors, abatacept, tocilizumab, or Janus kinase inhibitors between June 2013 and April 2019 at one of the 15 participating rheumatology centers were reviewed. We performed US assessment of articular synovia over 22 joints among bilateral wrist and finger joints, and the 22-joint (22j)-GS and 22-joint (22j)-PD scores were evaluated as an indicator of US activity using the sum of the GS and PD scores, respectively.The top 6 most affected joints included the bilateral wrist and second/third metacarpophalangeal joints. Therefore, 6-joint (6j)-GS and -PD scores were defined as the sum of the GS and PD scores from the 6 synovial sites over the aforementioned 6 joints, respectively. Although the 22j- or 6j-US scores were significantly correlated with DAS28-ESR or -CRP scores, the correlations were weak. Conversely, 6j-US scores were significantly and strongly correlated with 22j-US scores not only at baseline but also after therapy initiation.Using a multicenter cohort data, our results indicated that a simplified US scoring system could be adequately tolerated during any disease course among patients with RA receiving biological/targeted synthetic DMARDs.  相似文献   
6.
After 70 years with no confirmed autochthonous cases of dengue fever in Japan, 19 cases were reported during August–September 2014. Dengue virus serotype 1 was detected in 18 patients. Phylogenetic analysis of the envelope protein genome sequence from 3 patients revealed 100% identity with the strain from the first patient (2014) in Japan.  相似文献   
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Preconditioning is a preventative approach, whereby minimized insults generate protection against subsequent larger exposures to the same or even different insults. In immune cells, endotoxin preconditioning downregulates the inflammatory response and yet, preserves the ability to contain infections. However, the protective mechanisms of preconditioning at the tissue level in organs such as the kidney remain poorly understood. Here, we show that endotoxin preconditioning confers renal epithelial protection in various models of sepsis in vivo. We also tested the hypothesis that this protection results from direct interactions between the preconditioning dose of endotoxin and the renal tubules. This hypothesis is on the basis of our previous findings that endotoxin toxicity to nonpreconditioned renal tubules was direct and independent of immune cells. Notably, we found that tubular protection after preconditioning has an absolute requirement for CD14-expressing myeloid cells and particularly, macrophages. Additionally, an intact macrophage CD14-TRIF signaling pathway was essential for tubular protection. The preconditioned state was characterized by increased macrophage number and trafficking within the kidney as well as clustering of macrophages around S1 proximal tubules. These macrophages exhibited increased M2 polarization and upregulation of redox and iron-handling molecules. In renal tubules, preconditioning prevented peroxisomal damage and abolished oxidative stress and injury to S2 and S3 tubules. In summary, these data suggest that macrophages are essential mediators of endotoxin preconditioning and required for renal tissue protection. Preconditioning is, therefore, an attractive model to investigate novel protective pathways for the prevention and treatment of sepsis.  相似文献   
8.
Human monkeypox, an infectious disease caused by monkeypox virus (MPXV), is endemic to western and central Africa. A LightCycler quantitative PCR (LC-qPCR) system was developed for the diagnosis of this disease, targeting the A-type inclusion body gene (ATI gene) of MPXV. One naive monkey was infected with MPXV Zr-599 (Congo Basin strain) and one with MPXV Liberia (West African strain). Another three monkeys were immunized with smallpox vaccine on 0, 3, or 7 days, respectively, before infection with MPXV Zr-599. Peripheral blood cell (PBC) and throat swab (TS) specimens were serially collected. The LC-qPCR was validated for the diagnosis of monkeypox using virus isolation. Sequencing of the partial ATI gene revealed the insertion of a unique 453-nucleotide residue in the West African strains but not in the Congo Basin strains. Specific reverse primers for Congo Basin and West African strains were designed based on the unique sequence insertion. The LC-qPCR detected the MPXV genome, but not those of the other orthopoxviruses tested nor the varicella-zoster virus. Both the sensitivity and specificity of the LC-qPCR were over 90% in comparison to virus isolation when TS specimens were tested. Fourteen of the 15 virus isolation-positive PBC specimens showed positive reactions in the assay. Further, most PBC specimens collected from symptomatic monkeys in the later stage of illness showed positive reactions in the assay but negative reaction in virus isolation. It was possible to differentiate between these two groups with the LC-qPCR. Thus, the newly developed LC-qPCR is a useful and reliable diagnostic tool for MPXV infection.  相似文献   
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Purpose

We reviewed post-portoenterostomy (PE) biliary atresia (BA) patients who became “jaundice-free” (JF; total bilirubin (T-bil) ≤ 1.2 mg/dL) to determine factors associated with survival with the native liver (SNL).

Methods

We reviewed 76 BA patients treated by PE at our institute between 1989, when liver transplantation (LTx) became available in Japan, and 2012, prospectively. Of these, 60 who became JF and remained JF were divided into two groups, SNL (n = 44) and LTx (n = 16). Age and weight at PE, pre- and post-PE T-bil, AST, γ-GT, time taken to become JF, corticosteroid requirements, incidence of cholangitis, and micro-bile duct size were compared between the two groups.

Results

The SNL patients became JF significantly earlier: 58 vs. 115 days (p < .05). Corticosteroid requirement, cholangitis, and postoperative AST/γ-GT were significantly lower in the SNL patients (p < .05). SNL was significantly higher if patients became JF ≤ 60 days post-PE (p < .01). LTx was performed from 0.5 to 11 years post-PE (mean = 3.4). All patients who had cholangitis within 3 months of PE eventually required LTx (p < .05).

Conclusions

Becoming JF ≤ 60 days post-PE would appear to be a factor associated with SNL, while cholangitis within 3 months of PE would appear to be associated with LTx. Elevation of AST and γ-GT would also appear to be early indicators of risk for LTx during follow-up of JF patients after successful PE.  相似文献   
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