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91.
Bone marrow mesenchymal stem cells (BM-MSCs) are the main cellular components of the bone marrow, providing a supportive cellular microenvironment to maintain healthy hematopoiesis. β-thalassemia major (β-TM) is characterized by anemia that is caused by a genetic defect in hemoglobin synthesis and results in ineffective erythropoiesis (IE). The alterations in the microenvironment in thalassemic bone marrow during IE can cause changes in BM-MSCs. This study aimed to investigate global structural and compositional changes in BM-MSCs in β-TM that may provide a basis in understanding interactions of hematopoietic stem cells (HSCs)-MSCs in such a pathological bone marrow microenvironment. Following characterization of morphological, immunophenotypical, and differentiation properties, the changes in healthy and thalassemic BM-MSCs before and after bone marrow transplantation (BMT) were examined by attenuated total reflection-Fourier transform infrared (ATR-FTIR). The significant increase in lipid, protein, glycogen, and nucleic acid contents in thalassemic BM-MSCs with respect to healthy BM-MSCs was attributed to enhanced cell proliferation and BM activity during IE. The significant decreases in the content of mentioned macromolecules in post-transplant group BM-MSCs versus pre-transplant BM-MSCs was interpreted as restoring effect of BMT therapy on IE and defective BM microenvironment. These alterations were also supported by ELISA results of erythropoietin (EPO) and growth differentiation factor (GDF15) in bone marrow plasma samples as a reflection of IE and by MTT proliferation assay on BM-MSCs. Based on these changes, sampling groups were discriminated by cluster analysis. These results provide information for the studies that concentrate on interactions between HSCs-MSCs in bone marrow.  相似文献   
92.

Background

Functional constipation is a clinical problem with an incompletely understood etiology. Functional bowel diseases have been shown to be related to inflammation in many studies in adults. In this study, we aimed to evaluate leukocytes, C-reactive protein, proinflammatory and anti-inflammatory cytokines, and neopterin levels in children with functional constipation.

Methods

Seventy-six children with constipation and 71 healthy controls (mean age 7.12 ± 3.46 years and 7.32 ± 4.33 years, respectively, P = 0.991) were included in the study. Leukocytes, C-reactive protein, interleukin (IL)-1β, IL-6, IL-10, IL-12, tumor necrosis factor-alpha (TNF-α) and neopterin levels were assessed in patients and healthy controls. Parameters were measured in the serum using enzyme-linked immunosorbent assay methods.

Results

Mean IL-6 (20.31 ± 12.05 vs. 16.2 ± 10.25 pg/mL, respectively, P = 0.003), IL-12 (181.42 ± 133.45 vs. 135.6 ± 83.67 pg/mL, respectively, P = 0.018) and neopterin levels (2.08 ± 1.12 vs. 1.52 ± 1.02 pg/mL, respectively, P = 0.001) were significantly higher in constipated children than healthy controls. Leukocyte and thrombocyte counts, C-reactive protein, and IL-1β, IL-10 and TNF-α levels did not show any difference between the two groups.

Conclusions

In this study, IL-6, IL-12 and neopterin levels of constipated patients were found to be higher than those of controls. These results indicate the presence of subclinical inflammation in children with functional constipation.
  相似文献   
93.
Purpose: To demonstrate the molecular effects of acute and chronic exposure to both 900 and 2100?MHz radiofrequency electromagnetic radiation (RF-EMR) on the hippocampal level/activity of some of the enzymes – including PKA, CaMKIIα, CREB, and p44/42 MAPK – from N-methyl-D-aspartate receptor (NMDAR)-related signaling pathways.

Materials and methods: Rats were divided into the following groups: sham rats, and rats exposed to 900 and 2100?MHz RF-EMR for 2?h/day for acute (1 week) or chronic (10 weeks), respectively. Western blotting and activity measurement assays were used to assess the level/activity of the selected enzymes.

Results: The obtained results revealed that the hippocampal level/activity of selected enzymes was significantly higher in the chronic groups as compared to the acute groups at both 900 and 2100?MHz RF-EMR exposure. In addition, hippocampal level/activity of selected enzymes was significantly higher at 2100?MHz RF-EMR than 900?MHz RF-EMR in both acute and chronic groups.

Conclusions: The present study provides experimental evidence that both exposure duration (1 week versus 10 weeks) and different carrier frequencies (900 vs. 2100?MHz) had different effects on the protein expression of hippocampus in Wistar rats, which might encourage further research on protection against RF-EMR exposure.  相似文献   

94.
95.
96.

Objective

To investigate the expression of the second form of GnRH (GnRH-II) in tumor tissue and peripheral blood mononuclear cells (PBMCs) in malignant and benign ovarian tumors in humans.

Study design

Sixty-six women were studied: 24 with epithelial ovarian carcinomas, 22 with benign ovarian tumors and 20 in the control group undergoing surgery. Malignant, benign and normal ovarian tissue and PBMCs were obtained for measurement of GnRH-II mRNA levels using quantitative real-time RT-PCR.

Result(s)

The expression of GnRH-II was found to be 1.5 times higher in malignant ovarian tumors compared with benign ovarian tumors and the control group in post-menopausal patients (P < 0.01). In the post-menopausal patient group with malignant ovarian tumors, there were significant positive correlations between serum FSH level and ovarian tissue GnRH-II mRNA expression (r = 0.68; P = 0.03), and serum LH level and ovarian tissue GnRH-II mRNA expression (r = 0.71; P = 0.02). Controls, benign and malignant groups were similar in terms of GnRH-II expression in PBMCs in the pre- and post-menopausal periods. There was no significant correlation between ovarian tissue GnRH-II mRNA expression vs. PBMC GnRH-II mRNA expression in patient and control groups.

Conclusion(s)

We have shown increased GnRH-II expression in human ovarian cancer tissue in post-menopausal women in vivo. Expression of GnRH-II in PBMCs did not reflect the local GnRH-II expression levels in ovarian tissue. These preliminary data suggest that local GnRH-II may participate in the regulation of ovarian tumor growth in post-menopausal women.  相似文献   
97.

Purpose

Complex fractures of the olecranon have always been a difficult condition for treatment. Successful reconstruction depends on restoration of the anatomic contributors to stability. The purpose of this study was to define the proximal ulna anatomy in detail with respect to fracture fixation and arthroscopy.

Methods

In 50 normal adult ulnae (26 left, 24 right); posterior olecranon height (POH), olecranon width (OW), trochlear notch width (TW), the distances between the olecranon and the trochlear notch on radial and ulnar sides (RTH, UTH), and proximal ulnar angulations were measured with a ruler and a digital goniometer.

Results

The average POH was 24.6 mm, OW was 23.1 mm, TW was 22.3 mm, RTH was 16.2 mm, and UTH was 15.8 mm. The mean value for proximal ulna torsion angle (PUTA) was found 11.1°. The mean varus angulation was 9.3°. The average articular angle was 27.7° and proximal ulnar dorsal angulation (PUDA) was 8°.

Conclusions

The unique bony architecture of the proximal ulna presents particular difficulties for the implants used in fracture fixation and arthroplasty of the elbow. Knowing the detailed anatomy of the variations of proximal ulna will guide the surgeon to obtain a more reliable length of the olecranon and to offer a safe place for Kirschner wire replacement concerning humero-ulnar joint functionality. In this study, PUTA was also defined. The angle determines the rotation of the proximal ulna and it has a great importance for the movements of the joint. The measured angulations will help the surgeon to design the proper prosthesis for the maintenance of the functions of the elbow joint.  相似文献   
98.
The activation of Nod‐like receptor protein 3 (NLRP3) has lately been implicated in stress and depression as an initiator mechanism required for the production of interleukin (IL)‐1β and IL‐18. Agmatine, an endogenous polyamine widely distributed in mammalian brain, is a novel neurotransmitter/neuromodulator, with antistress, anxiolytic and antidepressant‐like effects. In this study, we examined the effect of exogenously administered agmatine on NLRP3 inflammasome pathway/cytokine responses in rats exposed to restraint stress for 7 days. The rats were divided into three groups: stress, stress+agmatine (40 mg/kg; i.p.) and control groups. Agmatine significantly down‐regulated the gene expressions of all stress‐induced NLRP3 inflammasome components (NLRP3, NF‐κB, PYCARD, caspase‐1, IL‐1β and IL‐18) in the hippocampus and prefrontal cortex (PFC) and reduced pro‐inflammatory cytokine levels not only in both brain regions, but also in serum. Stress‐reduced levels of IL‐4 and IL‐10, two major anti‐inflammatory cytokines, were restored back to normal by agmatine treatment in the PFC. The findings of the present study suggest that stress‐activated NLRP3 inflammasome and cytokine responses are reversed by an acute administration of agmatine. Whether antidepressant‐like effect of agmatine can somehow, at least partially, be mediated by the inhibition of NLRP3 inflammasome cascade and relevant inflammatory responses requires further studies in animal models of depression.  相似文献   
99.
Folliculotropic mycosis fungoides (FMF) is characterized by a broad clinical spectrum and worse prognosis compared to classical MF. This study aimed to evaluate the clinical characteristics, treatment modalities and long‐term outcome and risk factors for progression and survival of FMF patients. We conducted a single‐center retrospective study and reviewed 53 patients diagnosed with FMF between 1990 to 2019 in a referral center at Ankara University, Turkey. Regarding to stage at diagnosis, 24 patients (45.3%) had advanced‐stage disease (≥IIB). Follicular papules was observed in 66% and alopecia in 49.1% of the cases. Forty‐three patients (81.1%) suffered from pruritus. The majority of the patients (92.4%) had at least one systemic therapy. Complete remission was achieved in 24.5% of the patients. The median time of overall survival (OS) was 50 months (range 9‐324 months) and 5‐year and 10‐year OS was 83% and 69%, respectively. Twenty‐eight (52.3%) patients progressed to more advanced stages and seven (13.2%) patients died due to MF during the follow‐up period. FMF is associated with a progressive course and in most patients, skin‐directed therapies were found to be inefficient to control the disease and multiple systemic therapeutic agents were required to control the disease.  相似文献   
100.
Platelets are critically involved in the development of cerebral ischemia. Our study aimed to establish an association between frequent (minor allele frequency (MAF) > 5%) genetic polymorphisms in 84 candidate genetic loci previously linked to platelet reactivity by the use of next-generation sequencing of exons from pooled DNA samples in Polish patients with a history of large-vessel ischemic stroke. Genetic analysis was performed on blood samples obtained from 500 patients (diagnosed with acute non-cardioembolic ischemic stroke with coexisting large-artery atherosclerosis) and age/sex/history of smoking matching 500 controls of Polish origin with high risk of cardiovascular disease. Sequencing of 10 pools (five for each ischemic and control groups) was performed on the Ilumina HiSeq2500 sequencer which generated an average of 36.1 (22.7–45.9 range) million pair-end 101 bp reads and 5.3 (3–7 range) Gbp per pooled sample consisting of 100 subjects. In total, we observed 789 frequent polymorphisms in the sequenced 84 genes (703 of single-nucleotide polymorphism (SNP) type and 86 indels). When the MAF between control and stroke groups was compared, only two intronic polymorphisms (1 SNP and 1 indel) in RGS7 (rs127445 36) and ANKS1B (rs398098426) genes, respectively, show statistically significant differences, which persisted after individual genotyping of the variants and adjustment for potential confounding factors. From the remaining variants, 35 polymorphisms displayed various degrees of nominal significance (from 0.6.3 × 10?5 to 5 × 10?2) and 754 polymorphisms did not show any statistical significance when comparison was evaluated for differences in MAF between the study groups. In conclusion, the results of the study demonstrate statistically significant differences in two frequent intronic genetic variants (in RGS7 and ANKS1B) that could be associated with the platelet function between ischemic stroke patients with coexisting large-vessel atherosclerosis and control patients having high vascular risk.  相似文献   
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