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排序方式: 共有91条查询结果,搜索用时 46 毫秒
1.
Several pieces of evidence support the involvement of immune system in Menière's disease (MD). Macrophage migration inhibitory factor (MIF) plays a key role in immune‐mediated reactions. Several studies have shown an association between MIF gene polymorphisms and susceptibility to various inflammatory and autoimmune disorders. The aim of this study was to explore the association between MIF‐173 G/C polymorphism and MD in an Iranian population. In this case–control association study, MD cases (N = 72) were recruited and were comprised of definitive MD (N = 58) and probable MD (N = 14) subjects. Normal healthy subjects (N = 100) were also included. Genotyping for MIF‐173 G/C polymorphism was carried out using PCR‐RFLP technique. There was a significant increase in genotype GG in patients with MD compared with the control group. (GG vs. GC + CC, P = 0.02, OR = 2.08, 95% CI: 1.02–4.3). This was more significant when definitive MD was stratified and compared with the controls (GG vs. GC + CC, P = 0.009, OR = 2.6, 95% CI = 1.19–6.18). This study's result indicates the potential role of MIF in MD of which further evaluation is required. Also, the more significant association between MIF gene polymorphism and definitive MD designates the involvement of specific pathogenic mechanisms which may be considered as a marker for diagnosis.  相似文献   
2.
In a previous paper, we have noticed the effectiveness of two further attenuated measles vaccines, i.e. AIK-HDC and Edmonston- Zagreb- HDC. In the present study the same strains are comparatively used for immunization of a limited number of children under 9 months of age. A seroconversion of 100% was observed. Following reimmunization, a significant increase of circulating antibodies for both strains was recorded. Two combined measles-mumps-rubella (MMR) vaccines were also produced by using the same measles strains. The seroconversion following utilisation of MMR prophylactics in susceptible children was 98.8 and 97.3 for AIK and Edmonston- Zagreb strains respectively.  相似文献   
3.
In this study, we investigated the prevalence of human papilloma virus (HPV) infection and TP53 expression in patients with squamous cell carcinoma (SCC) of the tongue and, subsequently, its significance in cervical lymph node metastases and tumor differentiation. Sections of formalin-fixed, paraffin-embedded tissue blocks from 94 histologically confirmed tongue SCC cases were investigated in this study. Immunohistochemistry was used to study TP53 expression, and polymerase chain reaction (PCR) was performed for the detection of high risk HPV types (16 and 18). The frequency of HPV-16 and HPV-18 infection was 10.6% and 16%, respectively. Overexpression of TP53 was observed in 70.2% of patients. Young patients (aged below 45 years) comprised 20% of all patients. There was no significant association between TP53, HPV-16, or HPV 18 presence and higher stages of the tumor, tumor differentiation, or presence of nodal metastasis. Although an association between head and neck SCC and HPV infection is being recognized and reported, our data implicate that HPV infection or TP53 expression does not play a significant role in oral tongue SCC pathogenesis, differentiation, or metastasis, as seen in our patients.  相似文献   
4.
We conducted this study to investigate whether CAG repeat length in androgen receptor gene and GSTM1 and GSTT1 polymorphisms influence prostate cancer risk in Iranian newly diagnosed cancer patients compared to age-matched BPH group and healthy individuals. DNA from 110 pathologically-confirmed prostate cancer patients, 99 age-matched men with Benign Prostatic Hyperplasia (BPH) and 100 healthy individuals were extracted and amplified by polymerase chain reaction (PCR). PCR products were examined by electrophoresis and sequencing. The mean number of CAG repeat in prostate cancer patients was significantly smaller than normal (19.9 vs 22.8; p < 0.0001) and BPH groups (19.9 vs 21.9; P < 0.0001) The mean difference between normal individuals and BPH group was also significant (21.9 vs. 22.8; P = 0.003). Presence of GSTM1 null genotype were significantly higher in cancer and BPH group vs. normal individuals (both P values < 0.0001). there was not seen association between GSTT1 null or positive genotype with cancer risk, but analysis of GSTM1 null and GSTT1 positive in combination was statistically associated with Prostate cancer risk (OR = 8.4, 95% CI 1.53–46.73). Our results showed that CAG repeat polymorphism in AR gene may act as a risk modifier and GSTM1 null genotypes also may be contributed to prostate cancer susceptibility in Iranian patients.  相似文献   
5.
羟甲芬太尼(I)是一个新的高强度高选择性阿片μ受体激动剂。本文用cis-A-N-[1-(2-羟基-2-苯乙基)-3-甲基-4-哌啶基]-苯胺(II)或cis-N-[1-(苯甲酰甲基)-3-甲基-4-哌啶基]-苯胺(III)作为前体合成了[11C]-羟甲芬太尼,以便用正电子发射断层扫描(PET)来观察μ受体。通过水解cis-A-羟甲芬太尼(I)和cis-N-[1-(苯甲酰甲基)-3-甲基-4-哌啶]-N-苯基丙酰胺(cis-IV)的4-N-丙酰基分别获得II和III。溴乙烷的格氏试剂与回旋加速器产生的[11C]-二氧化碳反应后继而直接加入邻苯二甲酸二酰氯和2,6-二叔丁基吡啶生成同位素标记中间体[11C]-丙酰氯。[11C]-丙酰氯与OH-前体(II)反应后再经HPLC分离纯化直接得[11C]-羟甲芬太尼;[11C]-丙酰氯与酮-前体(III)反应后,再用硼氢化钠甲醇溶液处理,然后进行HPLC分离纯化得[11C]-羟甲芬太尼。两种方法均可获得ll.1~14.8GBq/μmol的特异性放射化学纯[11C]-羟甲芬太尼。总共耗时为40~50min(EOB)。  相似文献   
6.
Balloon aortic valvuloplasty (BAV) may be considered a palliative procedure that is performed in patients who have severely symptomatic aortic stenosis and a prohibitive surgical risk. However, due to poor early survival rates, most previous studies have involved a single BAV procedure. We analyzed long-term outcomes in patients who had severe aortic stenosis and BAV that incorporated repeat procedures to maintain symptom relief and increase survival rate. We retrospectively analyzed 212 consecutive nonsurgical patients (59 to 104 years old) who had severe calcific aortic stenosis and underwent 282 cumulative BAV procedures. Demographic, procedural, and follow-up mortality data were collected. BAV was performed with single or incremental balloon dilatation to obtain a postprocedural transaortic gradient close to 1/3 of the baseline gradient. Peak transaortic gradient after BAV decreased from 55 +/- 22 to 20 +/- 11 mm Hg and aortic valve area increased from 0.6 +/- 0.2 to 1.2 +/- 0.3 cm(2). Mean follow-up duration was 32 +/- 18 months. During follow-up, 24% of patients underwent a second BAV and 9% of patients underwent a third BAV. Duration of symptom alleviation after the first, second, and third BAV procedures were 18 +/- 3, 15 +/- 4, and 10 +/- 3 months, respectively. Median survival rate after BAV was 35 months. Survival rates 1, 3, and 5 years after the procedure were 64%, 28%, and 14% respectively. Patients who underwent repeat BAV had higher 3-year survival rates than did patients who underwent 1 BAV (p = 0.01). Therefore, repeat BAV is a viable treatment strategy in nonsurgical patients who have severe calcific aortic stenosis, because it provides a median survival rate of approximately 3 years and maintains clinical improvement.  相似文献   
7.
Immunophenotyping of lymphocytes is very essential for evaluation of immune system. Due to the effect of environmental factors and ethical diversity on immune system, establishment of an internal normal range of lymphocyte subsets is a necessity for each population. The aim of this study was to determine the normal range of T and B lymphocytes, and NK cells in normal Iranian adults. Two hundred and thirty three Iranian normal adult volunteers took part in this study. Complete Blood Count (CBC) was performed for them with Sysmex (KX21) and cells with CD3, CD4, CD8, CD19 and CD16/56 surface markers were simultaneously detected by flow cytometry method with FACstar system. Their percentile and absolute count were determined.The volunteers were 150 male and 83 female. Mean percentages of lymphocyte subpopulation were: CD3 (67.66 ±7.76), CD19 (14.41±5.09), CD4 (39.22±6.7), CD8 (25.42 ±5.4) and CD16/56 (10.14±6.42). Also, their mean absolute count of lymphocyte bearing CD3, CD19, CD4 and CD8 were 1,504±505/μl, 332±186/μl, 827±313/μl and 522±185/μl, respectively.Our results are comparable with similar Asian results from other Asian population, but are different from European population, we therefore conclude that it is necessary for each laboratory to establish an internal normal range for the lymphocytes bearing above- mentioned markers.  相似文献   
8.
9.
Aims and objectiveTo characterize the phenotype of CAPN1 (SPG76) mutations in patients diagnosed with hereditary spastic paraplegia (HSP).BackgroundThe CAPN1 gene, located on chromosome 11q13.1, is a protein-coding gene involved in neuronal plasticity, migration, microtubular regulation and cerebellar development. Several families with CAPN1 mutations have recently been reported to present with autosomal recessive (AR) HSP and/or ataxia.MethodPatients with HSP were identified through neurological and genetic clinics with detailed phenotyping. Whole exome sequencing revealed novel pathogenic CAPN1 mutations in four patients from 3 families.ResultsAffected families were of Turkish, Japanese, and Punjabi descent and all were consanguineous. Onset of spastic paraplegia in the four patients was between 20 and 37 years. Two also had mild ataxia. Three different novel, homozygous mutations in CAPN1 were found: c.2118+1G > T, c.397C > T, c.843+1G > C. The patient with the earliest onset also manifested profound muscle weakness, likely related to a second homozygous mutation in DYSF (dysferlinopathy).ConclusionsThe phenotype of AR CAPN1 mutations appears to be spastic paraplegia with or without ataxia; onset is most commonly in adulthood. Eye movement abnormalities, skeletal defects, peripheral neuropathy and amyotrophy can sometimes be seen. Occasionally, patients can present with ataxia, illustrating the genotypic and phenotypic overlap between HSP and spastic ataxia. With the advent of exome sequencing, mutations in more than one gene can be identified, which may contribute to the phenotypic variation, even within a family.  相似文献   
10.

PURPOSE

Veneering porcelain might be delaminated from underlying zirconia-based ceramics. The aim of this study was the evaluation of the effect of different surface treatments and type of zirconia (white or colored) on shear bond strength (SBS) of zirconia core and its veneering porcelain.

MATERIALS AND METHODS

Eighty zirconia disks (40 white and 40 colored; 10 mm in diameter and 4 mm thick) were treated with three different mechanical surface conditioning methods (Sandblasting with 110 µm Al2O3 particle, grinding, sandblasting and liner application). One group had received no treatment. These disks were veneered with 3 mm thick and 5 mm diameter Cercon Ceram Kiss porcelain and SBS test was conducted (cross-head speed = 1 mm/min). Two and one way ANOVA, Tukey''s HSD Past hoc, and T-test were selected to analyzed the data (α=0.05).

RESULTS

In this study, the factor of different types of zirconia ceramics (P=.462) had no significant effect on SBS, but the factors of different surface modification techniques (P=.005) and interaction effect (P=.018) had a significant effect on SBS. Within colored zirconia group, there were no significant differences in mean SBS among the four surface treatment subgroups (P=0.183). Within white zirconia group, "Ground group" exhibited a significantly lower SBS value than "as milled" or control (P=0.001) and liner (P=.05) groups.

CONCLUSION

Type of zirconia did not have any effect on bond strength between zirconia core and veneer ceramic. Surface treatment had different effects on the SBS of the different zirconia types and grinding dramatically decreased the SBS of white zirconia-porcelain.  相似文献   
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