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51.

Objective

The authors investigated the effectiveness of a functionalized tricalcium phosphate (fTCP) combined with a low fluoride level in a mouthrinse to reharden eroded enamel lesions.

Methods

Ninety enamel slabs attached in pairs to removable appliances were randomly assigned to three treatment groups (n?=?30/group): (T1) NaF rinse (225 ppm F?+?40 ppm fTCP), (T2) NaF rinse (225 ppm F; ACT®), and (T3) no mouthrinse (saliva). While wearing the in situ appliance for 14 days, subjects brushed their teeth with 1100 ppm F toothpaste (Crest©) for 2 min, rinsed with 15 ml of water for 10s, and then rinsed with 15 ml of their assigned treatment mouthrinse. Treatment efficacy was evaluated using surface microhardness (SMH) and transverse microradiography (TMR). Intra- and intergroup comparisons (α?=?0.05) were performed using the t-test and ANOVA followed by the Tukey test (HSD).

Results

With SMH, intragroup comparison (t-test) indicated significant rehardening of the eroded lesion with exposure to T1 (p?<?0.001) and T2 (p?<?0.01) but not with T3 However, with TMR, remineralization was only significant (p?=?0.01) with T1, but not with T2 and T3. In the intergroup comparison with percentage change in SMH, T1 was significantly different from T3 (p?<?0.01; Tukey HSD) but not from T2, and T2 was significantly different from T3. Intergroup comparison based on percentage mineral gain showed that T2 (p?=?0.02) and T3 (p?=?0.01) differed significantly from fTCP, but not between each other.

Conclusion

Addition of low level fluoride to functionalized β-tricalcium phosphate promoted rehardening of eroded enamel lesions.
  相似文献   
52.

Background

Sun exposure is critical for vitamin D synthesis and is a major risk factor for the development of non-melanoma skin cancer (NMSC). NMSC is the most common type of cancer in Brazil and coexists with a very high prevalence of vitamin D deficiency.

Objectives

The present study aimed to assess serum 25-hydroxyvitamin D (25[OH]D) concentration in patients with a recent diagnosis of NMSC.

Materials & methods

The serum 25(OH)D concentration of patients with a histological diagnosis of NMSC, made between September 2016 and September 2017, was measured by chemiluminescence up to 60 days after diagnosis and compared to healthy individuals without NMSC matched by age, sex, BMI, and skin phototype.

Results

Forty-one patients with NMSC and 200 healthy controls were evaluated. Most of the patients were men (56.1%) and most had basal cell carcinoma (90.2%). Patients were 67 years old on average (21-87 years) with skin Phototype 2 or 3 (80.6%). Mean serum 25(OH)D concentration inNMSCpatientswas significantly higher than in healthy controls (p<0.001). Most of the patients with NMSC (65.9%) had vitamin D deficiency (25[OH]D <30 ng/mL). No association was identified between histological type, time from diagnosis, or a previous history of skin neoplasm and 25(OH)D measurements.

Conclusion

Patients with recently diagnosed NMSC had significantly higher serum levels of 25(OH)D when compared to healthy controls. On the other hand, most of the NMSC patients were still considered to have vitamin D insufficiency.
  相似文献   
53.
The activation of PI3K further activates subsequent regulatory pathways, which are activated via AKT phosphorylation. AKT is closely related to the Bcl-2 family, a protein known to be involved in cell survival. AKT also has a relationship with inflammatory and glycolytic mediators. The present work aimed to evaluate the relationship between the PI3K/AKT pathway, cell survival/proliferation, inflammatory mediators and the glycolytic pathway in oral squamous cell carcinoma. All experiments were performed in the SCC25 oral squamous cell carcinoma cell line. In the presence or absence of PI3K pathway inhibitors, we analyzed the protein expression of pAKT and AKT; X-linked inhibitor of apoptosis protein; Bcl-2-associated death promoter; Bcl-2-like protein two inhibitor; cyclooxygenase 1; cyclooxygenase-2; and glycoprotein-associated glucose transporter 1. For the functional characterization of treated or untreated cells, we also performed matrix invasion assays, cell migration assays, and cell proliferation assays. Our results demonstrated that activation of the PI3K/AKT pathway is directly related to members of the Bcl-2 family and GLUT1, but not the inflammatory mediators COX1 and COX2. Our data suggest that the PI3K/AKT pathway is related to cell survival and proliferation in oral squamous cell carcinoma through its interaction with Bcl-2 family members.  相似文献   
54.
Infertile women often experience chronic stress, which may have a negative impact on general well‐being and may increase the burden of infertility. In this open‐label, parallel, randomized controlled trial, infertile women aged 18–50 years (median 37 years) were assigned to an 8‐week mindfulness‐based program (MBP) or no intervention. The primary outcome was stress severity measured by the Lipp's Stress Symptoms Inventory (ISSL). Data were analyzed by modified intent‐to‐treat principle, which included all cases available to follow‐up regardless of adherence to the intervention (62 participants from the MBP group and 37 from the control group). The median number of symptoms of chronic stress recorded in the past month decreased from six (interquartile range 2 to 9) before the MBP to two (interquartile range 1 to 4) after the intervention (p < 0.001, repeated measures analysis of variance with Time × Group interaction). Depressive symptoms also decreased after MBP, whereas general well‐being improved (p < 0.01 for both outcomes). Hair cortisol and serum brain‐derived neurotrophic factor (BDNF) did not change significantly between preintervention and postintervention. None of the outcomes changed significantly in the control group. MBP was effective in reducing stress and depressive symptoms while increasing general well‐being in infertile women.  相似文献   
55.
56.
Azevedo E  Manzano GM  Silva A  Martins R  Andersen ML  Tufik S 《Pain》2011,152(9):2052-2058
We investigated the effects of total and rapid eye movement (REM) sleep deprivation on the thermal nociceptive threshold and pain perception using the objective laser-evoked potential (LEP) and the subjective visual analogue scale (VAS). Twenty-eight male adult volunteers were assigned into Control (CTRL), Total (T-SD), and REM (REM-SD) Sleep Deprivation groups. The T-SD and REM-SD volunteers were totally or selectively deprived of sleep for 2 and 4 consecutive nights, respectively. Pain parameters were measured daily during the experimental period. Volunteers were stimulated on the back of the hand by blocks of 50 diode laser pulses. Intensities increased between successive blocks, ranging from nonnoxious to noxious levels, and the LEP threshold was identified based on the evoked-response onset. Both the LEP threshold and VAS ratings were significantly increased after the second night of T-SD. No significant variations were observed in the REM-SD group, suggesting a predominant role for slow wave sleep rather than selective REM-SD in pain perception. Also, for both sleep-deprived groups, the mean values of the LEP threshold and VAS ratings showed a gradual increase that was proportional to the SD deprivation time, followed by a decrease after 1 night of sleep restoration. These findings demonstrate a hyperalgesic modification to pain perception (as reflected by the augmented VAS) and a concomitant increase in the LEP threshold following T-SD, an apparently contradictory effect that can be explained by differences in the ways that attention affects these pain measurements.  相似文献   
57.
Innate immune responses against microorganisms may be mediated by Toll-like receptors (TLRs). Intestinal ischemia–reperfusion (i-I/R) leads to the translocation of bacteria and/or bacterial products such as endotoxin, which activate TLRs leading to acute intestinal and lung injury and inflammation observed upon gut trauma. Here, we investigated the role of TLR activation by using mice deficient for the common TLR adaptor protein myeloid differentiation factor 88 (MyD88) on local and remote inflammation following intestinal ischemia. Balb/c and MyD88?/? mice were subjected to occlusion of the superior mesenteric artery (45 min) followed by intestinal reperfusion (4 h). Acute neutrophil recruitment into the intestinal wall and the lung was significantly diminished in MyD88?/? after i-I/R, which was confirmed microscopically. Diminished neutrophil recruitment was accompanied with reduced concentration of TNF-α and IL-1β level. Furthermore, diminished microvascular leak and bacteremia were associated with enhanced survival of MyD88?/? mice. However, neither TNF-α nor IL-1β neutralization prevented neutrophil recruitment into the lung but attenuated intestinal inflammation upon i-I/R. In conclusion, our data demonstrate that disruption of the TLR/MyD88 pathway in mice attenuates acute intestinal and lung injury, inflammation, and endothelial damage allowing enhanced survival.  相似文献   
58.
The aim of this study was to report the occurrence of cryptosporidiosis in gray brocket deer in Brazil. Fecal samples of a male and a female Mazama gouazoupira kept in captivity in southern Brazil were evaluated. Samples collected at 10-d intervals were analyzed by the centrifugal flotation technique and stained by the modified Ziehl–Neelsen and by the Kinyoun staining methods. The first analysis showed a high number of Cryptosporidium parvum oocysts in the feces, associated with the presence of diarrhea in both animals. However, even without drug therapy, the number of oocysts of the protozoan decreased and the feces returned to normal after 10 days. This is the first report of cryptosporidiosis in M. gouazoupira.  相似文献   
59.
Water aerobics exercise is widely recommended for elderly people. However, little is known about the acute effects on hemodynamic variables. Thus, we assessed the effects of a water aerobic session on blood pressure in hypertensive elderly women. Fifty hypertensive elderly women aged 67.8 ± 4.1 years, 1.5 ± 0.6 m high and BMI 28.6 ± 3.9 kg/m2, participated in a crossover clinical trial. The experiment consisted of a 45-minute water aerobics session (70%–75% HRmax adjusted for the aquatic environment) (ES) and a control session (no exercise for 45 minutes) (CS). Heart rate was monitored using a heart rate monitor and systolic blood pressure (SBP) and diastolic (DBP) measurements were taken using a semi-automatic monitor before and immediately after the sessions, and at 10, 20 and 30 minutes thereafter. It was using a generalized estimating equation (GEE) with Bonferroni’s post-hoc test (p < 0.05). At the end of the experimental session, ES showed a rise in SBP of 17.4 mmHg (14.3%, p < 0.001) and DBP of 5.4 mmHg (7.8%, p < 0.001) compared to CS. At 10 minutes after exercise, BP declined in ES by a greater magnitude than in CS (SBP 7.5 mmHg, 6.2%, p = 0.005 and DBP 3.8 mmHg, 5.5%, p = 0.013). At 20 minutes after exercise and thereafter, SBP and DBP were similar in both ES and CS. In conclusion, BP returned to control levels within 10–20 minutes remaining unchanged until 30 minutes after exercise, and post-exercise hypotension was not observed. Besides, BP changed after exercise was a safe rise of small magnitude for hypertensive people.  相似文献   
60.
AIM: To investigate effects of severe burn injury(BI) in rat liver through the histopathological and inflammatory markers analysis. METHODS: Forty-two male Wistar rats were distributed into two groups, control(C) and subjected to scald BI(SBI). The animals were euthanized one, four and 14 d post sham or 45% of the total body surface BI. Liver fragments were submitted to histopathological, morphoquantitative(hepatocyte area and cell density), ciclooxigenase-2(COX-2) immunoexpression, and gene expression [real-time polymerase chain reaction for tumor necrosis factor(TNF)-α, inducible nitric oxide synthase(i NOS) and caspase-3] methods. RESULTS: Histopathological findings showed inflammatory process in all periods investigated and hepatocyte degeneration added to increased amount of connective tissue 14 d post injury. Hepatocyte area, the density of binucleated hepatocytes and density of sinusoidal cells of SBI groups were increased when compared with control. COX-2 immunoexpression was stronger in SBI groups. No differences were found in TNF-α, i NOS and caspase-3 gene expression. CONCLUSION: BI induces histopathological changes, upregulation of COX-2 immunoexpression, and cell proliferation in liver of rats.  相似文献   
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