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991.
Aim: We aimed to investigate the prophylactic effects of trimetazidine (TMZ) against contrast-induced nephropathy (CIN) in rat kidneys. Methods and results: 28 Wistar rats were divided into 4 groups of 7 rats each (control (C), contrast media (CM) TMZ, trimetazidin?+?contrast media groups (TMZ?+?CM). The administration of TMZ solution was done on d2, d3 and d4. Fifth day, contrast media was administered at a single dose. On d6 scarification was performed. The oxidant/antioxidant parameters were measured and histopathological scores were performed in kidney tissues. Most of the histopathological scores were significantly higher in the CM group as compared to other groups. Moreover, the scores of the TMZ?+?CM and C groups were not statistically different. CM group, had significantly higher levels of MDA compared to the C and CM?+?TMZ groups (562.82?±?38.15 vs. 419.15?±?49.01 and 507.34?±?14.16 01?nmol/mg protein respectively) (p?0.001). CM group had significantly lower levels of SOD as compared to C, CM?+?TMZ and TMZ groups (p?0.05). Conclusion: To the best of our knowledge, this study for the first time, histopathologically demonstrated the effectiveness of TMZ for the prevention of CIN.  相似文献   
992.
993.

Background

The aim of this report is to describe the effect of daily hemodialysis on the growth of children with end-stage renal disease (ESRD).

Methods

We performed a prospective, observational study on 24 children with ESRD undergoing daily hemodialysis (DHD). The control group comprised 26 children on concurrent conventional hemodialysis (CHD), and the follow-up for both groups was 9.3?±?3.0 months. No patient received growth hormone (GH) therapy.

Results

At the onset of the study, the height-for-age Z-score was ?2.12?±?1.54 in the CHD group and ?2.84?±?2.27 in the DHD group (p?=?0.313). Assuming an increase of 0.5 standard deviation scores (SDS) of the height-for-age parameter as an improvement of growth, there were 33 % of patients in the DHD group and 8 % in the CHD group (p?=?0.035). The cumulative probability of gain in height for age at 12 months was 40 % in the DHD group versus 15 % in the CHD group (p?=?0.047). Also, 98 % of patients in the DHD group had an adequate total caloric intake, whereas 38 % in the CHD group reached this goal (p?<?0.001). No patient left the study due to intensification of the dialysis modality.

Conclusions

Our data show that the DHD favored a 0.5 SDS height gain in a third of patients without GH treatment. Dialysis intensification was not a cause for treatment dropouts, and DHD should be considered as a treatment for selected cases, especially small children.  相似文献   
994.
Non‐HLA antibodies (Abs) targeting vascular receptors are thought to have an impact on renal transplant injury. Anti‐angiotensin II type 1‐receptor‐activating antibodies (anti‐AT1R) have been mentioned to stimulate a severe vascular rejection, but the pretransplant screening has not been introduced yet. The aim of our study was to assess the incidence and importance of anti‐AT1R antibodies and their influence on renal transplant in the 1st year of observation. We prospectively evaluated the presence of anti‐AT1R antibodies in 117 consecutive renal transplant recipients in pre‐ and post‐transplant screening. Anti‐AT1R antibodies were observed in 27/117 (23%) of the analyzed recipients already before transplantation. The function of renal transplant was considerably worse in anti‐AT1R(+) group. The patients with anti‐AT1R Abs >9 U/ml lost their graft more often. Biopsy‐proven AR was described in 4/27 (15%) pts in the anti‐AT1R(+) group and 13/90 (14.4%) in the anti‐AT1R(?) group, but more severe cases of Banff IIB or antibody‐mediated rejection (AMR) were more often observed in anti‐AT1R (+) 4/27 (15%) vs. 1/90 (1.1%) in anti‐AT1R(+) (P = 0.009). Patients with anti‐AT1R Abs level >9 U/ml run a higher risk of graft failure independently of classical immunological risk factors. The recipients with anti‐AT1R Abs developed more severe acute rejections described as IIB or AMR in Banff classification. More recipients among the anti‐AT1R‐positive ones lost the graft. Our study suggests monitoring of anti‐AT1R Abs before renal transplantation for assessment of immunologic risk profiles and the identification of patients highly susceptible to immunologic events, graft failure, and graft loss.  相似文献   
995.

Introduction

The most common variant muscle of the ankle, peroneus quartus muscle, is located in the lateral leg compartment. In literature there is ambiguous nomenclature of this muscle because of its different origin and insertion sides. It is related to many pathologic conditions in the lateral ankle compartment but also it can be used as a tendon graft for reconstructive procedures.

Material and method

We dissected 115 cadaver legs and investigated prevalence of peroneus quartus. We also present 2 year result of a patient who had torn superior peroneal retinaculum reconstructed with peroneus quartus tendon.

Results

The peroneus quartus muscle, with a number of different attachments, was present in 5.2 % (6/115) of the legs. It most commonly arose from the peroneus brevis muscle and inserted into the retrotrochlear eminence of the calcaneus. Associated pathologies are longitudinal degeneration and tear in the tendon of peroneus brevis. There is no any association between the prevalence of peroneus quartus and the height of retrotrochlear eminence or presence of peroneal tubercule (p > 0.05). But there is strong relationship between peroneus brevis degeneration and peroneus quartus existence (p: 0.03). We also defined a new type of peroneus quartus with a bifurcated insertion around the peroneus brevis. In literature our case report is unique because we present a patient who has torn superior peroneal retinaculum which is reconstructed with peroneus quartus tendon with 2 year follow up.

Conclusion

Peroneus quartus may lead to some pathologic conditions (pain, snapping, tear, synovitis, etc.) in the lateral ankle compartment but it may be used to reconstruct some pathologic conditions. Orthopaedics, anatomists and radiologists should be aware of this accessory tendon structure because of its clinical importance.  相似文献   
996.

Summary

This study demonstrated an impaired biomaterial-mediated bone regeneration in a critical sized calvarial defect established within an ovariectomized rat model. Histological and microtomographic evidences were supported by an impaired osteoblastic gene expression and altered expression of estrogen receptors and adipogenic markers.

Introduction

This work aims to address the bone regeneration process in the ovariectomized rat model, by assessing a calvarial critical size defect implanted with a biocompatible bovine bone mineral graft.

Methods

Animals were randomly divided into two groups: Ovx (bilateral ovariectomy) and Sham (control surgery). Following 8 weeks, all animals were submitted to a surgical bicortical craniotomy (5-mm circular critical size defect), which was filled with a biocompatible mineral graft. Animals were euthanized at 1, 3, and 6 months following graft implantation (n?=?10), and results on the orthotopic bone regeneration process were blindly evaluated by radiographic, microtomographic, histological, histomorphometric, and gene expression techniques.

Results

In the attained model, in both Sham and Ovx groups, the bone regenerative process was found to occur in a slow-paced manner. Likewise, a qualitative evaluation of the microtomographic and histological analysis, as well as quantitative data from histomorphometric indexes, revealed reduced bone regeneration in Ovx animals, at the assayed time points. Significant differences were attained at the 3 and 6 months. Gene expression analysis revealed a reduced expression of osteoblastic-related genes and an altered expression of estrogen receptors and adipogenic markers, within the regenerating bone of Ovx animals.

Conclusions

Due to the similarities between the osteoporotic animal model and the human condition of postmenopausal osteoporosis, it might be relevant to consider the potential clinical implication of the osteoporotic condition in the biomaterial-mediated bone tissue healing/regeneration process.  相似文献   
997.
A recombinant chimaeric protein containing three Mycoplasma hyopneumoniae antigens (C-terminal portion of P97, heat shock protein P42, and NrdF) fused to an adjuvant, the B subunit of heat-labile enterotoxin of Escherichia coli (LTB), was used to immunize pigs against enzootic pneumonia. The systemic and local immune responses, as well as the efficacy of the chimaeric protein in inducing protection against experimental M. hyopneumoniae infection were evaluated. In total, 60 male piglets, purchased from a M. hyopneumoniae-free herd, at 4 weeks of age were randomly allocated to six different experimental groups of 10 animals each: recombinant chimaeric protein by intramuscular (IM) (1) or intranasal (IN) (2) administration, commercial bacterin by IM administration (3), and the adjuvant LTB by IM (4, control group A) or IN (5, control group B) administration. All groups were immunized at 24 and 38 days of age and challenged at 52 days of age. The sixth group that was not challenged was used as the negative control (IN [n = 5] or IM [n = 5] administration of the LTB adjuvant). Compared with the non-challenged group, administration of the chimaeric protein induced significant (P < 0.05) IgG and IgA responses against all individual antigens present in the chimaera, but it could not confer a significant protection against M. hyopneumoniae infection in pigs. This lack of effectiveness points towards the need for further studies to improve the efficacy of this subunit-based vaccine approach.  相似文献   
998.
Sibutramine is a serotonin and norepinephrine reuptake inhibitor indicated for the treatment of obesity. A pre‐clinical study showed that acute administration of sibutramine promoted anxiolytic‐ and panicolytic‐like effects in male rats. However, in clinical reports, sibutramine favoured the onset of panic attacks in women. In this study, the effect of sibutramine on experimental anxiety in females and the relevance of different oestrous cycle phases for this effect were analysed. In experiment 1, both male and female rats were submitted to acute intraperitoneal injection of sibutramine or vehicle 30 min. before testing in the elevated T‐maze (ETM) and in the open‐field test (OF). Females in the pro‐oestrus (P), oestrus (E), early dioestrus (ED) and late dioestrus (LD) phases were tested in the ETM and OF (experiment 2) or in the elevated plus‐maze (EPM) 30 min. after the injection of sibutramine. Sibutramine impaired the escape response in the ETM in both males and females. This effect was observed for P, E and ED, but not for LD females. Sibutramine altered neither the inhibitory avoidance in the ETM nor the behaviour of females in the EPM. Thus, sibutramine promoted a panicolytic‐like effect in female rats cycling at P, E and ED, but not in the LD phase and did not alter behaviours related to anxiety in both ETM and EPM. Considering that pre‐clinical studies aiming the screening of anxiolytic drugs employ male rodents, data here obtained reinforce the importance of better understanding the effects of drugs in females.  相似文献   
999.
1000.
We exposed water samples from a recreational lake dominated by the cyanobacterium Planktothrix agardhii to different concentrations of hydrogen peroxide (H2O2). An addition of 0.33 mg·L−1 of H2O2 was the lowest effective dose for the decay of chlorophyll-a concentration to half of the original in 14 h with light and 17 h in experiments without light. With 3.33 mg·L−1 of H2O2, the values of the chemical oxygen demand (COD) decreased to half at 36 and 126 h in experiments performed with and without light, respectively. With increasing H2O2, there is a decrease in the total and faecal coliform, and this effect was made more pronounced by light. Total and faecal coliform were inhibited completely 48 h after addition of 3.33 mg·L−1 H2O2. Although the densities of cyanobacterial cells exposed to H2O2 did not decrease, transmission electron microscope observation of the trichomes showed several stages of degeneration, and the cells were collapsed after 48 h of 3.33 mg·L−1 of H2O2 addition in the presence of light. Our results demonstrate that H2O2 could be potentially used in hypertrophic systems because it not only collapses cyanobacterial cells and coliform bacteria but may also reduce chlorophyll-a content and chemical oxygen demand.  相似文献   
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