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Macrophage-derived foam cells are formed as a result of the accumulation of cholesteryl ester (CE) not only in cytoplasm where CE is produced by the reesterification of free cholesterol derived from oxidized low density lipoprotein (OxLDL) undergoing hydrolysis, but also in lysosomes where the remaining CE of OxLDL is deposited. We examined the possible involvement of cytosolic phospholipase A(2)s (cPLA(2)s) in the production of CE through the reesterification and in the formation of foam cells. In [(3)H]oleic acid-labeled human acute monocytic leukemia (THP-1) cell-derived macrophages (THP-M) and mouse peritoneal macrophages (MPM), which possessed at least cPLA(2)alpha and cPLA(2)gamma, stimulation with OxLDL induced the production of [(3)H]cholesteryl oleate ([(3)H]CE).The production was suppressed by an inhibitor of cPLA(2)s. However, the inhibitor tended to slightly decrease total intracellular levels of CE, and did not affect the formation of foam cells, as estimated by staining with Oil Red O. In cPLA(2)alpha-knockout MPM, OxLDL-induced increases in [(3)H]CE and total CE did not differ from those in wild-type MPM. Our results suggest that cPLA(2)s other than cPLA(2)alpha contribute to the supply of fatty acids, which are utilized for the production of CE through the reesterification, in OxLDL-stimulated macrophages. However, the formation of foam cells could not be inhibited only by the suppression of cPLA(2)-mediated CE production.  相似文献   
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Objective Linked-color imaging (LCI), a new technology for image-enhanced endoscopy, emphasizes the color of the mucosa, and its practicality in the detection of early gastric and colon cancers has been reported. However, whether or not LCI is useful for the diagnosis of Barrett''s adenocarcinoma (BA) has been unclear. In this study, we explored whether or not LCI enhances the color difference between a BA lesion and the surrounding mucosa. Methods Twenty-one lesions from 20 consecutive patients with superficial BA who underwent endoscopic submucosal dissection between November 2014 and September 2017 were retrospectively examined. The color differences (ΔE*) between the inside and outside of the lesion were evaluated retrospectively using white-light imaging (WLI), blue-light imaging (BLI), and LCI objectively, based on a Commission Internationale de l''Eclairage (CIE) lab color system. Furthermore, we compared the morphology, color, and circumferential location of the lesion. Results The median values of the color difference (ΔE*) in WLI and BLI were 9.1 and 5.8, respectively, and no difference was observed. In LCI, the median color difference was 17.6, which was higher than that of WLI and BLI. Regardless of the morphology, color, and circumferential location of BA lesions, the color difference was larger in LCI than in WLI. Conclusion LCI increases the color difference between the BA and the surrounding Barrett''s mucosa.  相似文献   
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Invasive aspergillosis has become a serious problem in clinical practice, but the actual factor that confers virulence on the fungus has not been thoroughly elucidated. To identify and isolate the immunosuppressive substances produced by the fungus, the bioactivity of culture filtrates was assessed, and analyses of the culture filtrates were carried out. Culture filtrates from different strains of Aspergillus fumigatus were assessed for their effect on human polymorphonuclear leukocytes and murine macrophages. To assess their activities in vivo, their effect on the survival of mice infected by the fungus was also studied. Subsequently, the composition of the culture filtrates was analyzed by gas chromatography-mass spectrometry. The analyses revealed that the culture filtrates contained gliotoxin at concentrations of 3 to 4µg/ml, and some other unidentified compounds. The bioactivities of the culture filtrates were similar to those of gliotoxin. The fungal culture filtrate reduced the survival of infected mice, but the filtrate itself did not cause the death of mice. However, all the bioactivities could not be accounted for by gliotoxin itself. These results indicate that gliotoxin in the culture filtrates may be responsible for part of the immunosuppressive activity, but some other components produced by A. fumigatus contribute, in an additive or synergistic manner, to the virulence of the fungus.  相似文献   
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Background

Additional surgery for all patients with noncurative resection after endoscopic resection (ER) for early gastric cancer (EGC) may be excessive due to the relatively low rate of lymph node metastasis (LNM) in such patients. However, the prevalence and risk factors for LNM after noncurative ER have not been consistent across studies.

Methods

We performed a systematic review of electronic databases through August 10, 2018 to identify cohort studies with patients who underwent additional surgery after noncurative ER for EGC. The prevalence of LNM in such patients was extracted for all studies. Odds ratios (ORs) were combined using random-effects meta-analyses to assess the risk of LNM, when possible.

Results

We identified 24 studies comprising 3877 patients with 311 having LNM (pooled prevalence, 8.1%). The risk of LNM was significantly increased in lymphatic invasion (OR [95% confidence interval] = 4.22 [2.88–6.19]), lymphovascular invasion (LVI) (4.17 [2.90–5.99]), vascular invasion (2.38 [1.65–3.44]), positive vertical margin (2.16 [1.59–2.93]), submucosal invasion depth of ≥ 500 μm (2.14 [1.48–3.09]), and tumor size > 30 mm (1.77 [1.31–2.40]). In contrast, there was no significant association between undifferentiated-type or ulceration (scar) and LNM. When studies were restricted to those that evaluated the adjusted OR, the risk of vascular invasion for LNM did not reach statistical significance.

Conclusions

Several pathological factors, most notably lymphatic invasion and LVI, were associated with LNM in patients with noncurative resection after ER for EGC. Lymphatic and vascular invasion should be assessed separately instead of LVI (PROSPERO CRD42018109996).

  相似文献   
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Exposure to cadmium (Cd) caused changes in the fatty acid composition of phospholipids, such as increases in levels of saturated and (n-6) fatty acids and decreases in levels of (n-9) fatty acids, in the liver phospholipids of rats fed a fat-free diet. These changes were similar to those caused by dietary zinc deficiency. The changes in fatty acid composition after administration of Cd were greater in zinc-deficient (ZD) rats than zinc-adequate (ZA) rats. When [14C]18:0 was injected intravenously in order to examine the metabolism of (n-9) fatty acids, a decrease in the rate of conversion of [14C]18:0 to [14C]18:1 was observed in liver phospholipids after treatment of ZD rats with Cd. These results suggested that Cd can affect the metabolism of fatty acids in relation to zinc status and, in particular, causes a reduction in the activity of Δ9-desaturase which converts 18:0 to 18:1.  相似文献   
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PurposeTo investigate whether or not intracytoplasmic sperm injection (ICSI) using spermatozoa extracted from testis (TESE‐ICSI) is a more effective treatment than ICSI with ejaculated spermatozoa (EJ‐ICSI) for primary ciliary dyskinesia (PCD).MethodsWe reported a case of PCD in which we performed TESE‐ICSI after repeated failure of EJ‐ICSI. Together with data from previous case reports, we compared the fertilization rate and pregnancy outcome of TESE‐ICSI and EJ‐ICSI.ResultsIn our case, TESE‐ICSI improved the morphology of spermatozoa and fertilization rate. However, the outcome was only a biochemical pregnancy. According to the analysis combined with previous reports, there was no difference in the fertilization rate and pregnancy outcome parameters between TESE‐ICSI and EJ‐ICSI.ConclusionsTESE‐ICSI for PCD may improve the fertilization rate compared to EJ‐ICSI. However, it does not necessarily improve the pregnancy outcome for a patient with primary ciliary dyskinesia.  相似文献   
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