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A biventricular bypass type total artificial heart (BVB-TAH) utilizing two pusher-plate pumps was developed and implanted in a sheep for 48 days with excellent results. A Hall effect sensor was utilized to operate each pump independently with a full stroke at variable rates (VR). With this system, the animal's hemodynamics was kept physiologically, and all metabolic parameters except hemoglobin and hematocrit returned to normal three weeks after implantation. However, signs of infection appeared on the forty-second day, and consequently the animal fell into a state of shock. Even at that time the BVB-TAH maintained circulation by increasing pumping rate automatically. On the forty-eighth day, the animal could not stand and suffered from anuria; the experiment was then terminated after 1,140 h pumping. At autopsy, there was an enlarged heart with an atrophic change, 1,900 ml of pleural effusion, and 3,100ml of ascites fluid. Blood culture taken on the forty-seventh day yielded Acinetobacter calcoaceticus. The BVB-TAH operated in an independent VR mode maintained entire circulation, and has a capability of substituting the native heart function in any situation.  相似文献   
3.
AIM: To evaluate the efficacy of granulocytapheresis therapy in alcoholic hepatitis. METHODS: We attempted to trap leukocytes in the peripheral circulation using the granulocytapheresis (GCAP) technique in patients with severe alcoholic hepatitis who showed a marked elevation of peripheral leukocytes. Corticosteroids were co-administered. RESULTS: The Maddrey's indices for these patients varied between 42 and 117 and MELD scores for alcoholic hepatitis (Mayo) ranged from 20 to 44. Survival rate was 50% (3/6), which is better than the results reported recently for similar patients in a national survey (29%). The effect of GCAP was reflected in decreases in interleukin-6 and interleukin-8 levels as well as in serum concentrations of soluble intercellular adhesion molecule. White blood cell counts were not affected. In the surviving patients, the Maddrey's indices and MELD scores for alcoholic hepatitis varied between 49 and 67, and 20 and 22, respectively, showing that GCAP is effective in patients with disease of moderate severity. Hemolytic anemia occurred in one patient after GCAP therapy. Other events such as pancreatitis, pneumonia, and cerebral hemorrhage were considered to be related to the alcoholic hepatitis itself. CONCLUSION: GCAP therapy deserves further evaluation as a new therapeutic modality for a moderately severe alcoholic hepatitis.  相似文献   
4.
Human papillomavirus (HPV) has several intragenotypic variants with different geographical and ethnic distributions. This study aimed to elucidate the distribution patterns of E6 and E7 (E6/E7) intragenotypic variants of HPV type 16 (HPV‐16), which is most common worldwide, and HPV‐52, which is common in Asian countries such as Japan, the Philippines, and Vietnam. In previous studies, genomic DNA samples extracted from cervical swabs were collected from female sex workers in these three countries and found to be positive for HPV‐16 or HPV‐52. Samples were amplified further for their E6/E7 genes using type‐specific primers and analyzed genetically. Seventy‐nine HPV‐16 E6/E7 genes were analyzed successfully and grouped into three lineages: European (Prototype), European (Asian), and African‐2. The prevalences of HPV‐16 European (Prototype)/European (Asian) lineages were 19.4%/80.6% (n = 31) in Japan, 75.0%/20.8% (n = 24) in the Philippines, and 0%/95.8% (n = 24) in Vietnam. The 109 HPV‐52 E6/E7 genes analyzed successfully were grouped into four lineages, A–D; the prevalences of lineages A/B/C/D were, respectively, 5.1%/92.3%/0%/2.6% in Japan (n = 39), 34.4%/62.5%/0%/3.1% in the Philippines (n = 32), and 15.8%/73.7%/7.9%/2.6% in Vietnam (n = 38). The distribution patterns of HPV‐16 and HPV‐52 lineages in these countries differed significantly (P < 0.000001 and P = 0.0048, respectively). There was no significant relationship between abnormal cervical cytology and either HPV‐16 E6/E7 lineages or specific amino acid mutations, such as E6 D25E, E6 L83V, and E7 N29S. Analysis of HPV‐16 and HPV‐52 E6/E7 genes can be a useful molecular‐epidemiological tool to distinguish geographical diffusion routes of these HPV types in Asia. J. Med. Virol. 85: 1069–1076, 2013. © 2013 Wiley Periodicals, Inc.  相似文献   
5.

Background

Hepatocellular carcinoma (HCC) is occasionally seen even in patients with autoimmune hepatitis (AIH) without prior infection either with hepatitis C virus (HCV) or hepatitis B virus. The aim of this study was to identify the incidence of and risk factors for HCC with AIH in a large-scale population with a long-term follow-up in Japan.

Methods

One hundred and eighty patients diagnosed with AIH were enrolled (F/M?=?159/21; mean age, 59.9?years; mean observation period, 80.2?months). Patients with positive HCV antibody/serum HCV RNA and/or positive HBs Ag were excluded. Initial treatment included immunosuppressant therapy (n?=?147), other drugs (n?=?28), and no drug (n?=?5). Patients underwent abdominal ultrasonography at intervals of 3–6?months during observation. Patients’ demographic factors, biochemical data, liver histology, medications, response to treatment, and complications were evaluated in relation to HCC.

Results

During the observation period, six patients (3.3%) developed HCC. Univariate analysis showed that risk factors for HCC were cirrhosis at diagnosis with AIH (p?=?0.0002), absence of a treatment response (p?=?0.033), abnormal alanine aminotransferase (ALT) at the final observation (p?=?0.0002), and diabetes (p?=?0.0015). Multivariate analysis showed that risk factors for HCC were cirrhosis at diagnosis of AIH (odds ratio 4.08) and abnormal ALT at final observation (odds ratio 3.66).

Conclusion

This retrospective study showed that cirrhosis at diagnosis of AIH and abnormal ALT at final observation were independently associated with HCC development. It is important to pay attention to the presence of cirrhosis at diagnosis of AIH and to normalize ALT.  相似文献   
6.
Valosin‐containing protein (VCP) is associated with multiple cellular functions, including ubiquitin‐dependent protein degradation. Mutations in VCP are known to cause inclusion body myopathy with Paget's disease and frontotemporal dementia and familial amyotrophic lateral sclerosis (fALS; ALS14), both of which are characterized by trans‐activation response DNA protein 43 (TDP‐43)‐positive neuronal cytoplasmic and nuclear inclusions. Recently, immunoreactivity for fALS‐associated proteins (TDP‐43, fused in sarcoma (FUS), optineurin and ubiquilin‐2) were reported to be present in cytoplasmic and nuclear inclusions in various neurodegenerative diseases. However, the extent and frequency of VCP‐immunoreactive structures in these neurodegenerative diseases are uncertain. We immunohistochemically examined the brains of 72 cases with neurodegenerative diseases and five control cases. VCP immunoreactivity was present in Lewy bodies in Parkinson's disease and dementia with Lewy bodies, and neuronal nuclear inclusions in five polyglutamine diseases and intranuclear inclusion body disease, as well as in Marinesco bodies in aged control subjects. However, other neuronal and glial cytoplasmic inclusions in tauopathies and TDP‐43 proteinopathies were unstained. These findings suggest that VCP may have common mechanisms in the formation or degradation of cytoplasmic and nuclear inclusions of neurons, but not of glial cells, in several neurodegenerative conditions.  相似文献   
7.
The 3-D morphology of doxorubicin (DOX)–loaded liposomes with a size of circa 100 nm was characterized by atomic force microscopy in an aqueous environment. Prolate liposomes appear in accordance with linear expansion of DOX fiber bundles precipitated inside liposomes. Oblate and concave liposomes were simultaneously observed with increased DOX concentrations; however, their morphologies were not readily determined by 2-D cryo-TEM imaging. Precise data analysis of the 3-D parameters of each liposome allowed semiquantitative evaluation of the transformation of spherical liposomes into nonspherical—prolate, oblate, and concave liposomes. In addition, nonspherical liposomes became spherical on the replacement of the liposomal outer phase consisting of a sucrose solution, with water and subsequent water influx. All spherical liposomes transformed into oblate and concave liposomes with a return to hyperosmotic conditions, when transferred from water to sucrose solution. Furthermore, the concave liposomes did not appear under DOX incubation conditions (65°C), which could be due to the amorphous and supersaturated DOX inside the liposomes that restrained liposomal shrinkage. As atomic force microscopy has improved our ability to image 3-D morphologies of liposomes in various conditions, it is an alternative analytical tool to cryo-TEM and may have future applications in regulatory tests for quality control and assurance.  相似文献   
8.
Cytoplasmic DNA triggers cellular immunity via activating the stimulator of interferon genes pathway. Since DNA is degradable and membrane impermeable, delivery system would permit cytoplasmic delivery by destabilizing the endosomal membrane for the use as an adjuvant. Herein, we report on the development of a plasmid DNA (pDNA)-encapsulating lipid nanoparticle (LNP). The structural components include an SS-cleavable and pH-activated lipid-like material that mounts vitamin E as a hydrophobic scaffold, and dual sensing motifs that are responsive to the intracellular environment (ssPalmE). The pDNA-encapsulating LNP (ssPalmE-LNP) induced a high interferon-β production in Raw 264.7 cells. The subcutaneous injection of ssPalmE-LNP strongly enhanced antigen-specific cytotoxic T cell activity. The ssPalmE-LNP treatment efficiently induced antitumor effects against E.G7-OVA tumor and B16-F10 melanoma metastasis. Furthermore, when combined with an anti-programmed death 1 antibody, an extensive therapeutic antitumor effect was observed. Therefore, the ssPalmE-LNP is a promising carrier of adjuvants for cancer immunotherapy.  相似文献   
9.
The infrapatellar fat pad (IFP) contains nerve fiber endings and is considered to play an important role in the perception of knee pain. However, it is unclear whether and to what degree prolonged pain influences the nociceptive role of the IFP. To answer this question, we established a novel rat model of knee pain in which inflammation is restricted to the IFP. Rats received a single intra-IFP injection of monoiodoacetic acid (MIA) (0.2 mg/10 µL or 1.0 mg/10 µL) in the left knee and a phosphate-buffered saline (10 µL) injection in the right knee as a control. Pain-avoidance behavior and histological changes of the knee joint were measured at multiple time points up to 28 days after MIA injection. Histological analysis showed a transient inflammatory response in the IFP body in the 0.2-mg model, whereas prolonged inflammation followed by fibrotic changes was observed in the 1.0-mg model. Subtle histological alterations were observed in the articular cartilage and IFP surface regardless of the dose. The pain-avoidance behavior test indicated the development of prolonged knee pain throughout the experimental period in the 1.0-mg group. Histological assessments showed a significant increase in calcitonin gene-related peptide (CGRP)-positive nerve fiber endings inside IFPs with fibrosis in newly vascularized surrounding regions. These data suggest that irreversible fibrotic changes in the IFP induce the formation of new vessels and CGRP-positive nerve fiber endings that associate prolonged pain in the joint.  相似文献   
10.
Identification of the proteinaceous components of the pathological inclusions is an important step in understanding the associated disease mechanisms. We immunohistochemically examined two previously reported cases with eosinophilic neuronal cytoplasmic inclusions (NCIs) (case 1, Mori et al. Neuropathology 2010; 30: 648–53; case 2, Kojima et al. Acta Pathol Jpn 1990; 40: 785–91) using 67 antibodies against proteins related to cytoskeletal constituents, ubiquitin‐proteasome system, autophagy‐lysosome pathway and stress granule formation. Regional distribution pattern of eosinophilic NCIs in case 1 was substantially different from that in case 2. However, NCIs in both cases were immunonegative for ubiquitin and p62 and were immunopositive for stress granule markers as well as autophagy‐related proteins, including valosin‐containing protein. Considering that eukaryotic stress granules are cleared by autophagy and valosin‐containing protein function, our findings suggest that eosinophilic NCIs in the present two cases may represent the process of autophagic clearance of stress granules.  相似文献   
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