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101.
Adrenal reserve depletion and overstimulation of the hypothalamus-pituitary-adrenal(HPA) axis are causes for adrenal insufficiency(AI) in critically ill individuals. Cirrhosis is a predisposing condition for AI in cirrhotics aswell. Both stable cirrhotics and liver transplant patients(early and later after transplantation) have been reported to present AI. The mechanisms leading to reduced cortisol production in cirrhotics are the combination of low cholesterol levels(the primary source of cortisol), the increased cytokines production that overstimulate and exhaust HPA axis and the destruction of adrenal glands due to coagulopathy. AI has been recorded in 10%-82% cirrhotics depending on the test used to evaluate adrenal function and in 9%-83% stable cirrhotics. The similarity of those proportions support the assumption that AI is an endogenous characteristic of liver disease. However, the lack of a gold standard method for AI assessment and the limitation of precise thresholds in cirrhotics make difficult the recording of the real prevalence of AI. This review aims to summarize the present data over AI in stable, critically ill cirrhotics and liver transplant recipients. Moreover, it provides information about the current knowledge in the used diagnostic tools and the possible effectiveness of corticosteroids administration in critically ill cirrhotics with AI.  相似文献   
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We sought to evaluate the feasibility of the retroperitoneum's exploration via natural orifice transluminal endoscopic surgery (NOTES) using transvaginal access in a porcine model, and its possible application in human beings. Six female pigs (25–30 kg) were used to establish anatomic landmarks and technical steps. Six additional pigs were used for the survival study. Under general anesthesia and with the pig supine, a 1-cm posterolateral colpotomy was performed with the double-channel gastroscope's needle knife. The incision was enlarged laterally using blunt dissection while keeping in contact with the psoas muscle. A retroperitoneal tunnel was created using carbon-dioxide dissection and the movements of the gastroscope up to the level of the kidney. The colpotomy site was closed using interrupted sutures (polyglactin 2/0). A follow-up laparoscopy and necropsy were performed 3 weeks postoperatively. Successful access to the retroperitoneum was achieved in all pigs with a mean operative time of 30 minutes. However, in the first 3 pigs used for the acute study, the peritoneum was perforated during the six-pig dissection and the procedure was abandoned because of the space's collapse. No perforation occurred during the survival study. An excellent view of the retroperitoneal space and structures, such as the vascular and lymphatic tissues, the kidney, the adrenal gland, and the ureter, was obtained. No intraoperative complications or bleeding or injury to any of the retroperitoneal structures occurred. The 3-week follow-up laparoscopy showed no adhesions or abscesses. These findings were confirmed at necropsy. The retroperitoneal space can be successfully accessed via NOTES. Transvaginal NOTES access to the retroperitoneum avoids any transparietal trocars, so it could decrease surgical trauma, be better tolerated, and offer better visualization, with the obvious gender limitation. Future clinical application in human beings may include procedures such as lymphadenectomy, nephrectomy, and adrenalectomy.  相似文献   
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Chronic lymphocytic leukemia (CLL) stereotyped subsets #6 and #8 include cases expressing unmutated B cell receptor immunoglobulin (BcR IG) (U-CLL). Subset #6 (IGHV1-69/IGKV3-20) is less aggressive compared to subset #8 (IGHV4-39/IGKV1(D)-39) which has the highest risk for Richter's transformation among all CLL. The underlying reasons for this divergent clinical behavior are not fully elucidated. To gain insight into this issue, here we focused on epigenomic signatures and their links with gene expression, particularly investigating genome-wide DNA methylation profiles in subsets #6 and #8 as well as other U-CLL cases not expressing stereotyped BcR IG. We found that subset #8 showed a distinctive DNA methylation profile compared to all other U-CLL cases, including subset #6. Integrated analysis of DNA methylation and gene expression revealed significant correlation for several genes, particularly highlighting a relevant role for the TP63 gene which was hypomethylated and overexpressed in subset #8. This observation was validated by quantitative PCR, which also revealed TP63 mRNA overexpression in additional nonsubset U-CLL cases. BcR stimulation had distinct effects on p63 protein expression, particularly leading to induction in subset #8, accompanied by increased CLL cell survival. This pro-survival effect was also supported by siRNA-mediated downregulation of p63 expression resulting in increased apoptosis. In conclusion, we report that DNA methylation profiles may vary even among CLL patients with similar somatic hypermutation status, supporting a compartmentalized approach to dissecting CLL biology. Furthermore, we highlight p63 as a novel prosurvival factor in CLL, thus identifying another piece of the complex puzzle of clinical aggressiveness.  相似文献   
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BACKGROUND: Common clinical practice for the provision of parenteral nutrition of neonates is to administer the nutrients in separate solutions. The aim of this study was to introduce and examine an alternative way of parenteral feeding for neonates, providing all-in-one parenteral regimes. METHODS: Stability studies were carried out on 2 all-in-one admixtures. Stability assays consisted of the assessment of the admixture's (1) macroscopic aspect, (2) drop size measurement, (3) pH measurement, (4) peroxide value, and (5) alpha-tocopherol concentration. For the measurements, the admixtures were stored at 2 different temperatures, 4 degrees C (storage) and 25 degrees C (compounding), and then analyzed at a starting time, 24 hours, 48 hours, and 7 days after compounding. RESULTS: The 2 all-in-one parenteral admixtures for neonates were shown to be physically stable under analysis conditions, and there were no particles larger than 1 mum. The maximum loss of alpha-tocopherol was approximately 24%. In all-in-one admixtures, lipid peroxide occurred within 24 hours after the addition of the lipid emulsion. CONCLUSIONS: The addition of fat emulsion and fat-soluble vitamins did not alter the physical stability of parenteral admixtures for neonates. Moreover, the admixtures examined were relatively chemically stable for 24 hours, as far as vitamin E is concerned. Lipid peroxidation was the limiting factor for application stability of an all-in-one neonatal parenteral regimen.  相似文献   
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Aim  To investigate the potential involvement of apoptosis and its regulators Bcl-2, Bax, and Fas within the retina in Staphylococcus epidermidis experimental endophthalmitis. Methods  Endophthalmitis was induced in 48 male Lewis rats by unilateral 25-μl intravitreal injection of 7,000 viable organisms of slime-producing S. epidermidis strain ATCC 35983 (experimental group). Forty-eight other Lewis rats received a similar sterile normal saline injection (control group). The injected eyes were graded for clinical inflammation and were removed in groups at 6, 12, 24, 48, 72, and 168 hours post-injection. After surgical separation, retinal tissue specimens were fixed, and paraffin sections underwent hematoxylin-eosin staining, immunohistochemistry against Bcl-2, Bax, and Fas, and TUNEL assay for detection of apoptotic cells. Following morphometric analysis, the apoptotic body index (ABI) was calculated. Results  While Bcl-2 expression was absent, Bax and Fas expression and apoptosis in ganglion cells, bipolar cells, and photoreceptors, were significantly higher in the experimental group compared to the control group (P < 0.05). In the experimental group, inflammation peaked at 24 hours, Bax and Fas expression at 48 hours and the ABI at 72 hours post-injection. Conclusion  Apoptosis is increased within the retina in S. epidermidis experimental endophthalmitis through upregulation of Bax and Fas, peaking soon after peak inflammation. Support: None Financial interest: None  相似文献   
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Significant anti-tumor responses have been reported in a small subset of cancer patients treated with the immunotherapeutic agent anti-CTLA-4 antibody. All clinical trials to date, comprising over 3,000 patients, have been conducted in the metastatic disease setting, which allows for correlation of drug administration with clinical outcome but has limited analyses of intermediate biomarkers to indicate whether the drug has impacted human immune responses within the tumor microenvironment. We conducted a pre-surgical clinical trial in six patients with localized bladder cancer, which allowed for correlation of drug administration with biomarkers in both blood and tumor tissues but did not permit correlation with clinical outcome. We found that CD4 T cells from peripheral blood and tumor tissues of all treated patients had markedly increased expression of inducible costimulator (ICOS). These CD4+ICOShi T cells produced IFN-gamma (IFNγ) and could recognize the tumor antigen NY-ESO-1. Increase in CD4+ICOShi cells led to an increase in the ratio of effector to regulatory T cells. To our knowledge, these are the first immunologic changes reported in both tumor tissues and peripheral blood as a result of treatment with anti-CTLA-4 antibody, and they may be used to guide dosing and scheduling of this agent to improve clinical responses.  相似文献   
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