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The aim of this experimental study was to investigate hepatotoxicity effects of noise and toluene, and in particular, to study hepatotoxicity effects of simultaneous exposure to noise and toluene by histopathological and biochemical experiments. To experiment hepatotoxicity effects of noise and toluene, 100 dB white noise and 1000 ppm toluene vapors were generated during two consecutive weeks in healthy male New Zealand White rabbits. Non-simultaneous exposure to noise and toluene increased liver enzymes and the serum levels of superoxide dismutase, malondialdehyde, and total antioxidant capacity, and also decreased serum level of glutathione peroxidase. Alanine transaminase, aspartate transaminase, gamma-glutamyl transferase, malondialdehyde, total antioxidant capacity, and superoxide dismutase levels increased by simultaneous exposure to noise and toluene. Furthermore, catalase and alkaline phosphatase level decreased by simultaneous exposure to noise and toluene. The hematoxylin and eosin stain (H&E) experiments indicated significant swelling, lipidosis, eosinophilic cytoplasm, pyknosis, karyorrhexis, and disruption of the cytoplasmic membrane in the liver tissue due to exposure to noise, toluene and simultaneous exposure to them.

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Signal copy number (SCN) and signal intensity (SI) of subtelomeres (ST) are investigated in auxiliary lymph node (ALN) and buccal (BUC) cells by fluorescence in situ hybridization. The extracted total cell of 38256 and 2309 was, respectively, analyzed from the benign ALN- and BUC-cells of an affected breast cancer patient. The Periodic model was based on ST behavior including normal-, down-, and upregulated clones with diverse SCN. The arm-p/q ratio based signature, as a subtelomeric array, reflects discordance and concordance of ST-behavior within individual chromosomes as a concept of “Individualization of Cells” rather than “Global Insight of Cells”. The Periodic charts could be considered as a reliable and refreshable platform through which the cellular evolution could be patterned and characterized. Signature of ST-profile in the BUC and ALN cells and the nature of diverse SCN and SI as quantitative and qualitative value led to modeling the real personalized perspective of cellular evolution. Protein expression of Ki67, Cyclin D1, and Cyclin E was assayed, as a complementary panel. These targets could be applied as the predictive and preventive markers for an early detection at BUC and ALN levels to plan the required managements in the breast cancer patients.  相似文献   
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The aim of the current study was to investigate the effects of dietary supplementation with thyme extract as growth promoter agent on growth performance, intestinal microbial populations, and thigh meat quality of Japanese quail. A total of one hundred eighty 1-day-old Japanese quails were randomly allocated to three treatments with four replicates per treatment and 15 quail chicks per pen. The dietary treatments consisted of basal control diet (CO) without any added compounds, virginiamycin (VM, 200 mg/kg), and thyme extract (TH, 100 mg/kg). Daily feed intake for each pen was recorded. The average body weight gain (BWG) and feed intake (FI) adjusted for mortality to 21 and 35 days of age were used to calculate the feed conversion ratio (FCR). At day 35, two birds per replicate were slaughtered for determination of intestinal weights and also for thigh meat quality. Supplementing VM significantly decreased the FCR of quails at day 35. The results showed that the count of lactobacillus bacteria increased in birds fed the TH diet compared to VM and CO treatments. Also, supplemental TH decreased the number of coliforms in the ileum compared to the CO diet. Japanese quails fed the TH diet had significantly lower 2-thiobarbituric acid-reactive substances (TBARS) than the VM and CO treatments. Water holding capacity (WHC) was significantly increased in quails fed the TH diet. In conclusion, TH can increase the number of beneficial bacteria (lactobacillus bacteria) and decrease harmful ones (coliforms). Also, TH has good effects on thigh meat quality as indicated by the decrease in TBARS and the increase in WHC, but it has not affected the growth performance.  相似文献   
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Our recent study has established that young blood factors are not causal, nor necessary, for the systemic rejuvenation of mammalian tissues. Instead, a procedure referred to as neutral blood exchange (NBE) that resets signaling milieu to a pro-regenerative state through dilution of old plasma, enhanced the health and repair of the muscle and liver, and promoted better hippocampal neurogenesis in 2-year-old mice (Mehdipour et al., Aging 12:8790–8819, 2020). Here we expand the rejuvenative phenotypes of NBE, focusing on the brain. Namely, our results demonstrate that old mice perform much better in novel object and novel texture (whisker discrimination) tests after a single NBE, which is accompanied by reduced neuroinflammation (less-activated CD68+ microglia). Evidence against attenuation/dilution of peripheral senescence-associated secretory phenotype (SASP) as the main mechanism behind NBE was that the senolytic ABT 263 had limited effects on neuroinflammation and did not enhance hippocampal neurogenesis in the old mice. Interestingly, peripherally acting ABT 263 and NBE both diminished SA-βGal signal in the old brain, demonstrating that peripheral senescence propagates to the brain, but NBE was more robustly rejuvenative than ABT 263, suggesting that rejuvenation was not simply by reducing senescence. Explaining the mechanism of the positive effects of NBE on the brain, our comparative proteomics analysis demonstrated that dilution of old blood plasma yields an increase in the determinants of brain maintenance and repair in mice and in people. These findings confirm the paradigm of rejuvenation through dilution of age-elevated systemic factors and extrapolate it to brain health and function.

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Bone metastasis accounts for the vast majority of breast cancer (BC) metastases, and is related to a high rate of morbidity and mortality. A number of seminal studies have uncovered gene expression signatures involved in BC development and bone metastasis; each of them points at a distinct step of the ‘invasion-metastasis cascade’. In this review, we provide most recently discovered functions of sets of genes that are selected from widely accepted gene signatures that are implicate in BC progression and bone metastasis. We propose a possible sequential pattern of gene expression that may lead a benign primary breast tumor to get aggressiveness and progress toward bone metastasis. A panel of genes which primarily deal with features like DNA replication, survival, proliferation, then, angiogenesis, migration, and invasion has been identified. TGF-β, FGF, NFκB, WNT, PI3K, and JAK-STAT signaling pathways, as the key pathways involved in breast cancer development and metastasis, are evidently regulated by several genes in all three signatures. Epithelial to mesenchymal transition that is also an important mechanism in cancer stem cell generation and metastasis is evidently regulated by these genes. This review provides a comprehensive insight regarding breast cancer bone metastasis that may lead to a better understanding of the disease and take step toward better treatments.  相似文献   
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Breast cancer is amongst the leading causes of death in women worldwide and the most common cancer amongst Iranian women. Unfortunately, the current clinical and histological criteria can only help 60 percent of women with breast cancer in diagnosis and long-term treatment. Therefore, genetic markers both at single gene and chromosomal level can play an important role in improving the diagnosis and prognosis of breast cancer patients. The aim of this retrospective study was to investigate the role of chromosome 1 and 8 copy number assessed by interphase fluorescence in situ hybridization (FISH), as prognostic parameters in 50 Iranian women, aged 35 to 64 years, with sporadic invasive ductal breast carcinoma. Chromosome 1 and 8 copy numbers were evaluated in relation to established clinicopathological parameters, the immunohistochemical markers ER, PR, P53 and cathepsin D, DNA index by flow cytometry, age and survival status of the patients. FISH using centromeric probes for chromosomes 1 and 8 was applied to interphase cell suspensions prepared from archived, Carnoyfixed tumor cells and selected paraffin-embedded tumor sections. Aneusomy for chromosomes 1 and 8 was present in all 50 patients to different levels. The total abnormality rate for chromosome 1 was 33.92 percent (4.24 percent monosomy and 29.68 percent polysomy), whereas for chromosome 8 this rate was 28.30 percent (6.48 percent monosomy and 21.82 percent polysomy). Statistically significant association (p<0.05) was demonstrated between monosomy 1 and patients’ age below 50 years, and between monosomy 1 and poor survival, respectively. Disomy 8 was significantly associated with P53 expression. A borderline significant correlation was demonstrated between polysomy 8 and diploid DNA content, as well as between disomy 1 and disease-free status of the patients. Chromosome 1 and 8 copy numbers may be considered as useful prognostic markers in invasive ductal carcinoma of the breast.  相似文献   
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PURPOSE: Transesophageal echocardiography has emerged as an accepted approach before D.C. cardioversion for atrial fibrillation. The frequency of atrial thrombi detected on transesophageal echocardiography has varied from 7% to 23%. Many patients undergoing transesophageal echocardiography have had a previous transthoracic echocardiogram. Though transthoracic echocardiography has a low yield for the detection of intracardiac thrombi, it is highly accurate in diagnosing a structurally abnormal heart. The purpose of this study was to assess the frequency of thrombi detected by transesophageal echocardiography in patients with an entirely normal transthoracic echocardiogram and hence the advocacy of a selective approach in performing transesophageal echocardiography in patients undergoing D.C. cardioversion for atrial fibrillation. METHODS: 112 consecutive patients with atrial fibrillation who had undergone transesophageal echocardiography before D.C. cardioversion were evaluated. They all had a transthoracic echocardiogram within the 2 months preceding their transesophageal echocardiogram. Based on their transthoracic echocardiographic study, they were divided into two groups: Group 1 consisted of patients with a normal transthoracic echocardiogram and Group 2, those with an abnormal study. RESULTS: Thrombi or spontaneous echo contrast were found in 14 of 112 patients (16%). All however were detected in Group 2 patients. There was no patient with a normal transthoracic echocardiogram who had thrombus on his/her transesophageal echocardiogram. CONCLUSIONS: Our results suggest that a selective approach may be exercised in the use of transesophageal echocardiography prior to D.C. cardioversion for atrial fibrillation. Patients with an entirely "normal" transthoracic echocardiogram may proceed directly to cardioversion without a precardioversion transesophageal echocardiogram.  相似文献   
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