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991.
Background:This study aimed to evaluate the efficacy of peri-induction forced air warming to prevent inadvertent perioperative hypothermia, defined as a reduction in body temperature to <36.0°C during the perioperative period, in intraoperatively warmed patients receiving major surgery lasting >120 minutes.Methods:In total, 130 patients scheduled for elective surgery under general anesthesia lasting >120 minutes were divided into 2 groups: peri-induction warming (n = 65) and control (n = 65). Patients in the peri-induction warming group were warmed during the anesthetic induction period using a forced-air warmer set at 47°C, whereas patients in the control group were covered passively with a cotton blanket. All patients were warmed with a forced-air warmer during surgery. Body temperature was measured using a tympanic membrane thermometer in the pre- and postoperative periods and using a nasopharyngeal temperature probe during surgery. Patients were evaluated for shivering scale score, thermal comfort scale score, and satisfaction score in the post-anesthesia care unit.Results:The incidence rates of intraoperative and postoperative hypothermia were lower in the peri-induction warming group than in the control group (19.0% vs 57.1%, P < .001; 3.3% vs 16.9%, P = .013, respectively). Body temperature was higher in the peri-induction warming group (P < .001). However, intraoperative blood loss, as well as postoperative thermal comfort scale score, shivering scale score, and patient satisfaction score, were similar between groups. Post-anesthesia care unit duration was also similar between groups.Conclusions:Peri-induction active forced air warming is an effective, simple, and convenient method to prevent inadvertent perioperative hypothermia in intraoperatively warmed patients undergoing major surgery lasting >120 minutes.  相似文献   
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993.
OBJECTIVES: The purpose of this study is to explore the synergistic effect of combining camphorquinone (CQ) with 1-phenyl-1,2-propanedione (PPD) as a new photoinitiator. METHODS: A BisGMA, UDMA, TEGDMA monomer mixture was made light-curing with CQ and/or PPD plus 0.2 wt.% N,N-cyanoethyl-methylaniline (CEMA). Seventeen groups, three specimens each, were tested in which the concentrations of PPD and CQ were varied. The effect of photosensitizer type (CQ or PPD) and ratio (PPD/CQ) on degree of conversion (DC) was investigated using FTIR spectrophotometry. The results were analyzed by ANOVA and Student-Newman-Keuls' multiple range comparison. The absorption spectra of PPD and CQ were recorded by UV-Vis spectrophotometry. A blind color comparison of specimens containing combinations of the two photosensitizers was also undertaken. RESULTS: Alone, PPD induces a DC which is not significantly different from that of CQ alone. In combination, CQ + PPD produces a DC that generally exceeds that produced by the same concentration of either used alone. The maximum DC occurs between PPD/CQ = 1:1 and 1:4. At total photosensitizer concentrations above 1.8 wt.%, DC is increased by PPD but depressed by CQ, which is evidence that different mechanisms are involved. PPD (lambda max approximately 410 nm) and CQ (lambda max approximately 468 nm) have different wavelength absorption ranges, resulting in a perceptibly lighter shade of yellow for PPD. SIGNIFICANCE: 1-phenyl-1,2-propanedione is a photosensitizer of potential value in reducing color problems associated with visible light cured dental resins. In combination with camphorquinone, it acts synergistically to produce a more efficient photoinitiation reaction.  相似文献   
994.
For very low birth weight (VLBW) infants, diagnostic and therapeutic decisions widely depend on hematological values. Although ethnic differences for hematologic parameters have been reported, few studies have been reported for Korean VLBW infants. This study aimed at defining the hematological reference values for medical research and clinical practice. Retrospectively we selected 149 infants confirmed as healthy at birth and had no medical conditions that may have affected the hematological profile. Hematological values obtained within the first 4 h after birth were classified into gestational age and we determined the influence of gender, mode of delivery, sampling site, 1-min and 5-min Apgar scores on these values. Red blood cell (RBC), hemoglobin (Hb) and hematocrit (Hct) values increased, whereas the white blood cell (WBC) and platelets decreased as the gestational age increased. In relation to the mode of delivery and the 5-min Apgar score, WBC, neutrophil, mean corpuscular volume (MCV), RBC, Hb, Hct and the platelets differed selectively. No differences in any hematological values were observed in relation to gender, sampling site, and the 1-min Apgar score. This study should be useful as a guide to the reference range of these hematological values for Korean VLBW infants.  相似文献   
995.
Melissa officinalis L. (Labiatae), Morus alba L. (Moraceae), and Artemisia capillaris Thunb. (Compositae) are suggested to be involved in the regulation of hyperlipidemia. We hypothesized that Ob-X, a mixture of three herbs, Morus alba, Melissa officinalis and Artemisia capillaris [corrected] improves lipid metabolism, body weight gain and adiposity and that peroxisome proliferator-activated receptor alpha (PPARalpha) is associated with these events. Mice fed a high-fat diet for 12 weeks exhibited increases in body weight gain and adipose tissue mass compared with mice fed a low fat diet. However, feeding a high-fat diet supplemented with Ob-X significantly reduced these effects. Ob-X treatment also decreased the circulating levels of triglycerides and total cholesterol, and inhibited hepatic lipid accumulation. Ob-X supplementation was found to increase the hepatic mRNA levels of PPARalpha target enzymes responsible for fatty acid beta-oxidation. Moreover, Ob-X elevated the endogenous expression of a luciferase reporter gene containing three copies of a PPAR response element (PPRE) in NMu2Li liver cells. These data demonstrate that Ob-X regulates body weight gain, adipose tissue mass, and lipid metabolism in part through changes in the expression of hepatic PPARalpha target genes.  相似文献   
996.
Gyeongshingangjeehwan (GGEx), which comprises Liriope platyphylla F.T. Wang & T. Tang (Liliaceae), Platycodongrandiflorum A. DC. (Campanulaceae), Schisandrachinensis K. Koch (Magnoliaceae), and Ephedra sinica Stapf (Ephedraceae), has traditionally been used as an anti-obesity drug in Korean local clinics, although there is no evidence concerning the scientific analyses of its effects and mechanism(s) of action. Thus, we investigated the effects of GGEx on obesity, as well as the mechanism by which GGEx functions, in Otsuka Long-Evans Tokushima Fatty (OLETF) male rats. Compared with obese OLETF control rats, administration of GGEx for 8 weeks significantly decreased food intake and plasma leptin levels as well as body weight gain and abdominal fat in OLETF rats. GGEx treatment not only decreased circulating triglycerides, but also inhibited lipid accumulation in the liver. GGEx increased the hepatic mRNA levels of PPARalpha target genes responsible for fatty acid beta-oxidation. Consistent with the in vivo data, GGEx elevated PPARalpha reporter gene expression in NMu2Li liver cells. These results suggest that GGEx may effectively prevent obesity and hypertriglyceridemia in part through the inhibition of feeding and the activation of hepatic PPARalpha.  相似文献   
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998.
999.
PURPOSEThe purpose of this study was to investigate changes in retention and wear pattern of Locator® and ADD-TOC attachments on a digital milled bar by performing chewing simulation and repeated insertion/removal of prostheses in fully edentulous models.MATERIALS AND METHODSLocator (Locator®; Zest Anchors Inc., Escondido, CA, USA) was selected as the control group and ADD-TOC (ADD-TOC; PNUAdd Co., Ltd., Busan, Republic of Korea) as the experimental group. A CAD-CAM milled bar was mounted on a master model and 3 threaded holes for connecting a bar attachment was formed using a tap. Locator and ADD-TOC attachments were then attached to the milled bar. Simulated mastication and repeated insertion/removal were performed over 400,000 cyclic loadings and 1,080 insertions/removals, respectively. Wear patterns on deformed attachment were investigated by field emission scanning electron microscopy.RESULTSFor the ADD-TOC attachments, chewing simulation and repeated insertion/removal resulted in a mean initial retentive force of 24.43 ± 4.89 N, which were significantly lower than that of the Locator attachment, 34.33 ± 8.25 N (P < .05). Amounts of retention loss relative to baseline for the Locator and ADD-TOC attachments were 21.74 ± 7.07 and 8.98 ± 5.76 N (P < .05).CONCLUSIONCAD-CAM milled bar with the ADD-TOC attachment had a lower initial retentive force than the Locator attachment. However, the ADD-TOC attachment might be suitable for long-term use as it showed less deformation and had a higher retentive force after simulated mastication and insertion/removal repetitions.  相似文献   
1000.
This study examined whether or not the ER stress and Bcl-2 proteins are linked to the protective effect of kaempferol, a phytoestrogen, on ischemia-reperfusion (I/R)-induced cardiac damage. In order to determine if kaempferol modifies the I/R-induced response in H9c2 cardiac muscle cells, the cells were exposed to kaempferol followed by ischemia 12h/reperfusion 4h. kaempferol had a protective effect on the apoptosis induced by I/R in the cardiac muscle cells. The Kaempferol treatment significantly increased the expression level of the anti-apoptotic protein, Bcl-2, but decreased the level of the pro-apoptotic protein, bax. Kaempferol down-regulated the expressions of the endoplasmic reticulum (ER) stress proteins, GRP78, ATF-6alpha, XBP-2, IRE1-alpha, phosphor-eIF-2alpha and CHOP. In ex vivo-Langendorff experiment, the kaempferol treatment regulated the expression of ER stress proteins-CHOP and GRP78. The kaempferol also improved the post-ischemic LVEDP and LVDP significantly after 20, 30, 40 and 50 min of reperfusion compared with the untreated control hearts, which shows that kaempferol offers protection against I/R-associated cardiac dysfunction.  相似文献   
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