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41.
This study was designed to elucidate the signalling pathways by which secretory phospholipases A2 (sPLA2s) induce in vitro neutrophil migration. The cell migration assays were performed with Naja mocambique venom PLA2 (sPLA2 with high catalytic activity), bothropstoxin-I (sPLA2 devoid of catalytic activity) and platelet-activating factor (PAF), using a 48-well microchemotaxis chamber. Both the non-selective protein kinase inhibitor staurosporine (30-300 nM) and the selective protein kinase C (PKC) inhibitor 1-(5-isoquinolinesulfonyl)-2-methylpyperazine (H7; 50-200 microM) as well as the Gi inactivator pertussis toxin (30-300 nM) caused a concentration-dependent inhibition of the neutrophil migration induced by either N. mocambique venom PLA2 (100 microg/ml) or bothropstoxin-I (100 microg/ml). Pertussis toxin nearly abolished PAF-induced migration, while staurosporine and H7 partly (but significantly) inhibited the chemotactic responses to PAF. The dual inhibitor of cytosolic PLA2 and Ca2+ -independent PLA2 (iPLA2), arachidonil-trifluoromethyl-ketone (ATK; 0.2-20 microM), or the specific iPLA2 inhibitor bromoenol lactone (1-30 microM) caused a concentration-dependent inhibition of the migration induced by either sPLA2s. At the maximal concentration used for each compound, the migration was almost suppressed. In contrast, both of these compounds caused only slight inhibitions of PAF-induced migration. No rise in intracellular Ca2+ was observed in neutrophil-stimulated sPLA2, as determined in cells preloaded with fura 2-AM. In the experimental condition used, pertussis toxin, staurosporine, H7, ATK or bromoenol lactone did not induce cytotoxic effects, according to MTT assay. Our results suggest that activation of an endogenous PLA2 through activation of GTP-binding protein and PKC is the main mechanism by which exogenous sPLA2s cause neutrophil migration.  相似文献   
42.
Low-level laser therapy (LLLT) has been widely used in the treatment of the stomatognathic system dysfunction; however, its biological effect remains poorly understood. This study evaluated the effect of LLLT (GaAlAs, 780 nm, 20 J/cm², 40 mW) on masseter muscle of HRS/J mice after different numbers of laser irradiations (three, six, and ten) for 20 s in alternate days. Three experimental groups were defined according to the number of laser irradiations and three control groups (n?=?5) were used. On the third day after the last irradiation, all animals were killed and the masseter muscle was removed and processed for the following analysis: (a) transmission electron microscopy, (b) zymography, (c) immunohistochemistry for vascular endothelial growth factor (VEGF) and VEGFR-2. The results showed: (a) with six laser applications, a dilation of T tubules, and sarcoplasmic reticulum cistern, increased pinocytosed vesicles in the endothelium; with ten laser applications, few pinocytic vesicles in the endothelium and condensed mitochondria. (b) Under the conditions of this study, the synthesis of other matrix metalloproteinases was not observed, only the MMP-2 and -9. (c) After ten laser irradiations, immunostaining was observed only for VEGFR-2. We conclude that after six laser applications, ultrastructural changes may facilitate the Ca+2 transfer to cytosol and increase the fluid transport from one surface to another. The ultrastructural changes and no immunostaining for VEGF with ten applications may decrease the metabolic activity as well as damage the angiogenic process, suggesting that an effective number of laser applications may be less than ten, associating to this therapy a better cost–benefit.  相似文献   
43.
AIM: To compare the effectiveness of an interactive multimedia courseware package versus standard lectures regarding knowledge, understanding, and transfer of content, as well as problem-solving skills in orthodontics. METHODS: Pre- and post-test assessments of final-year dental students (n = 26), who either used an interactive multimedia courseware package (n = 15) or attended standard lectures (n = 11) on equivalent material of the undergraduate orthodontic curriculum were carried out. Both groups were tested by written and multiple-choice questions covering knowledge, understanding, and application areas in the curriculum. A one-way anova was carried out in order to check statistical difference between the two groups. The P-value was set at 0.05. RESULTS: There was no difference in prior knowledge between the groups at baseline. Generally, no significant difference was seen between the two groups in relation to answers to questions about knowledge, understanding, and application in the orthodontic curriculum. However, both groups improved their scores after the course. In one question investigating the extent of understanding the instructional content of the multidisciplinary orthodontic treatment, the multimedia courseware package group scored significantly better. CONCLUSION: In this study, the instructional interactive multimedia program was found to be at least as effective as the standard lecture of the orthodontic curriculum for undergraduate training in orthodontics.  相似文献   
44.
n = 39) or mail ( n = 6), and 3 (1%) were inaccessible for follow-up since discharge from the hospital. The mean follow-up period was 29.8 months (range 0–67 months). A total of 33 incisional hernias were observed in the mesh group and 41 in the no-mesh group. There was no significant difference in the distribution of herniation time between the two groups ( p = 0.43). The two main predictive factors of herniation were age and weight. In conclusion, the use of an intraperitoneal polyglactin mesh does not prevent postoperative incisional hernias in obese patients.  相似文献   
45.
Congenital granular cell lesion of the newborn, also known as congenital epulis, is a rare benign oral cavity tumor presenting at birth. Usually, it appears as a solitary mass arising in the mouth and originates from the anterior alveolar ridge. The objective of the present article is to report a case of congenital granular cell lesion in an 8-day-old female newborn. The patient presented four intraoral pedunculated lesions. Diagnosis, treatment, microscopic and immunohistochemical characteristics are also discussed.  相似文献   
46.
Dry extract of the genus Passiflora has been shown to help control glycemia and lipid levels. The objective of this study was to evaluate the effects of passion fruit (P. edulis) on the biochemical profile of offspring from diabetic rats. Diabetes was induced by streptozotocin. The diabetes group consisted of 10 rats with glucose levels greater than 200 mg/dL; the nondiabetic (control) group consisted of 10 rats with glucose levels less than 120 mg/dL. After the diagnosis of diabetes, the mating phase was started. By day 21 of pregnancy, the offspring were born; the dams were kept in individual cages with their offspring until the weaning period. The offspring were then divided into 4 groups (n=15 each): G1 were offspring from control dams, G2 were offspring from treated nondiabetic dams, G3 were offspring from diabetic dams, and G4 were offspring from treated diabetic dams. For 30 consecutive days, G1 and G3 offspring were treated with vehicle (oral gavage) and G2 and G4 offspring were treated with passion fruit juice (oral gavage). After 30-day treatment, the animals were anesthetized and killed, and blood was drawn immediately for analysis of the biochemical profile (total cholesterol, high-density lipoprotein cholesterol, low-density lipoprotein cholesterol, triglycerides, and glucose). The G2 and G4 rats showed significantly reduced total cholesterol, triglyceride, and low-density lipoprotein cholesterol levels and an increased high-density lipoprotein cholesterol level. The use of passion fruit juice improved lipid profiles, suggesting that this plant may have beneficial effects in the prevention and treatment of dyslipidemias and hyperglycemia.  相似文献   
47.
PURPOSE: The administration of anabolic-androgenic steroids (AAS) to improve athletic performance has increased notably during the past three decades, even among nonathletes. Thyroid function is affected by AAS use in humans, although the mechanisms of the effects of AAS are unclear. We evaluated the effects on thyroid function of supraphysiologic doses of nandrolone decanoate (DECA), which is one of the most anabolic-androgenic steroids (AAS) used. METHODS: Male Wistar rats were treated with vehicle or 1 mg.100 g(-1) body weight (b.w.) of DECA, once a week for 8 wk, intramuscularly. We analyzed thyroperoxidase (TPO) activity, type 1 iodothyronine deiodinase (D1) activities in liver, kidney, pituitary, and thyroid, and serum levels of total T3, total T4, free T4, and TSH. Parametric and nonparametric t-tests were employed for statistical analyses. RESULTS: Treated animals showed a significant increase in the weight of kidneys and heart, and a decrease in the relative testis weight. Retroperitoneal adipose tissue was only slightly decreased. DECA treatment induced a significant increase in the absolute and relative thyroid gland weight. The concentrations of total serum T3, free T4, and TSH decreased significantly with treatment, but total serum T4 levels were unchanged. Thyroperoxidase activity was unaltered, whereas liver and kidney D1 activities were significantly increased, but pituitary and thyroid D1 did not change. CONCLUSION: Our data indicate that DECA exerts direct actions on the thyroid gland and in the peripheral metabolism of thyroid hormones and might lead to thyroid dysfunction.  相似文献   
48.
Levels of carbamazepine, carbamazepine-10,11-epoxide and ?10,11-diol were measured in the plasma of 40 patients with affective disorders chronically treated with carbamazepine. Steady-state plasma levels of carbamazepine were not related to the degree of prophylactic response. In contrast, the mean plasma concentrations of the ?10,11-epoxide metabolite of carbamazepine were significantly lower in patients with complete response than in patients with partial response or in nonresponders. The ratios of carbamazepine-10,11-diol concentrations to the parent drug dose were found to be significantly different in the three response groups. These results suggest that the pharmacokinetic parameters of the metabolites might be used for the prediction of individual prophylactic efficacy at the initial stage of carbamazepine therapy.  相似文献   
49.
Leishmania tropica in Egypt: an undesirable import   总被引:1,自引:0,他引:1  
Cutaneous as well as visceral leishmaniasis has been previously reported in Egypt. The former clinical manifestation is attributed to Leishmania major, the latter to L. infantum. In this study, L. tropica was isolated from an Egyptian labourer returning from Saudi Arabia. Amastigotes were detected by both Giemsa staining and indirect immunofluorescence using rabbit anti-gp63. Promastigotes from Schneider's medium were typed isoenzymatically as L. tropica. In view of the emerging threat of visceralization of L. tropica, the potential risk for its transmission in Egypt is discussed.  相似文献   
50.
Granulocyte macrophage-colony-stimulating factor (GM-CSF), released from alveolar macrophages (AM), is an important regulator of eosinophil, T cell, and macrophage function and survival. We determined the mechanisms of GM-CSF regulation in AM from normal volunteers activated by lipopolysaccharide (LPS) by examining the role of nuclear factor-kappaB (NF-kappaB), and of p38 mitogen-activated protein (MAP) kinase and MAP kinase kinase (MKK-1). PD 098059 (10 microM), an inhibitor of upstream activator of MKK-1, inhibited GM-CSF expression, but the expression of GM-CSF was not inhibited by SB 203580 (10 microM), an inhibitor of p38-MAP kinase. Phosphorylation of extracellular signal-regulated kinase-1 (ERK-1), ERK-2, and p38 MAP kinase by LPS were demonstrated on Western blot analysis. LPS increased NF-kappaB:DNA binding as examined by electrophoretic mobility shift assay, but this was not suppressed by PD 098059 or by SB 203580. LPS induced an increase in NF-kappaB activation as examined by p50 translocation assay without suppression by PD 098059 or by SB 203580. SN50 (100 microM), an inhibitor of NF-kappaB translocation and the specific IKK-2-Inhibitor (AS602868; 10 microM), also prevented GM-CSF expression and release induced by LPS, indicating that GM-CSF release is NF-kappaB-dependent. PD 098059, but not SB 203580, inhibited LPS-induced histone acetyltransferase (HAT) activity, indicating chromatin modification. Furthermore, AS602868 and SN 50 suppressed LPS-induced HAT activity. TSA (10 ng/ml), an inhibitor of histone deacetylase (HDAC), reversed the inhibitory effect of PD 098059, SB 203580, SN 50 and AS602868 on GM-CSF release. GM-CSF expression and release in AM is controlled by NF-kappaB activation, and this is modulated by phosphorylation of MKK-1 and p38 MAP kinase acting on histone acetylation.  相似文献   
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