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Apoptosis is critical for organ development, tissue homeostasis, the elimination of abnormal cells and the maintenance of immune homeostasis by variable regulatory mechanisms. The death of T lymphocytes following their activation involves a series of proteases (caspases), which comprise the central executioners of apoptosis. Abnormal regulation of apoptosis results in disease. T-cell resistance against apoptosis contributes to inappropriate T-cell accumulation and the perpetuation of the chronic inflammatory process in inflammatory bowel disease with potential tumourigenic effect. The use of antitumour necrosis factor-alpha, anti-interleukin-6R and anti-interleukin-12 antibodies suppresses colitis activity by induction of T-cell apoptosis, thereby having important implications for the design of effective therapeutic strategies in inflammatory bowel diseases. Contrary to international data, the incidence of cancer in Greek patients with inflammatory bowel disease appears to be low. A balance between cell proliferation (Ki-67 overexpression) and apoptosis (Bax protein overexpression) may partly explain the low incidence of cancer development in Greek inflammatory bowel disease patients.  相似文献   
3.
The relations between structure and isothermal, dielectric properties of poly(α-acetoxystyrene)s substituted in para position by ? OCOCH3 ( 1a ), ? OCOCH2CH3 ( 1b ), ? OCOCH2CH2CH3 ( 1c ), ? OCOC6H5 ( 1d ), ? OCOCH2CH2Cl ( 1f ) and ? OCOOCH3 ( 1g ) were studied. The dielectric constants, at 105 Hz and 20 ± 2°C, were found to be: 3,79 ( 1a ), 3,36 ( 1b ), 3,18 ( 1c ), 3,51 ( 1d ), 3,36 ( 1e ), 3,65 ( 1f ) and 3,07 ( 1g ). The polymers 1a – 1g do not show any α- or β-transition. Increasing bulkiness of the para substituent gives rise to a decreasing dielectric constant due to an increase of the degree of syndiotacticity, as determined from 1H and 13C NMR spectra.  相似文献   
4.
The tumor immune microenvironment of oral tongue squamous cell carcinoma may be accountable for differences in clinical behavior, particularly between different age groups. We performed RNA expression profiling and evaluated tumor infiltrating lymphocytes (TILs) and their T-cell subsets in order to assess the functional status of oral tongue squamous cell carcinoma tumor microenvironment and detect potentially clinically useful associations. Archival surgical pathology material from sixteen oral tongue squamous cell carcinoma patients was microscopically evaluated for TIL densities. RNA was extracted from macrodissected whole tumor sections and normal controls and RNA expression profiling was performed by the NanoString PanCancer IO 360 Gene Expression Panel. Immunostains for CD4, CD8 and FOXP3 were evaluated manually and by digital image analysis. Oral tongue squamous cell carcinomas had increased TIL densities, numerically dominated by CD4 + T cells, followed by CD8 + and FOXP3 + T cells. RNA expression profiling of tumors versus normal controls showed tumor signature upregulation in inhibitory immune signaling (CTLA4, TIGIT and PD-L2), followed by inhibitory tumor mechanisms (IDO1, TGF-β, B7-H3 and PD-L1). Patients older than 44 years showed a tumor microenvironment with increased Tregs and CTLA4 expression. Immunohistochemically assessed CD8% correlated well with molecular signatures related to CD8 + cytotoxic T-cell functions. FOXP3% correlated significantly with CTLA4 upregulation. CTLA4 molecular signature could be predicted by FOXP3% assessed by immunohistochemistry (R2 = 0.619, p = 0.026). Oral tongue squamous cell carcinoma hosts a complex inhibitory immune microenvironment, partially reflected in immunohistochemically quantified CD8 + and FOXP3 + T-cell subsets. Immunohistochemistry can be a useful screening tool for detecting tumors with upregulated expression of the targetable molecule CTLA4.Electronic supplementary materialThe online version of this article (10.1007/s12105-020-01229-w) contains supplementary material, which is available to authorized users.  相似文献   
5.
In a rat model, the left kidney was subjected to 60 min of normothermic ischemia followed by 15 min of reperfusion, whereas the right kidney, serving as a paired control, was not rendered ischemic. Both kidneys were then perfused in situ with either Euro-Collins (EC) solution (n=12) or University of Wisconsin (UW) solution (n=6) for 10 min. Each kidney was then harvested and stored at 4°C in its respective solution. After 24 and 48 h of cold storage, the following vasoactive substances were measured in the preservation media: endothelin (ET), angiotensin II (A-II), thromboxane (B2) (TxB2), and prostaglandin I2 (PGI2). After 24 h in EC solution, left kidneys uniformly produced significantly higher concentrations of each vasoactive substance than right kidneys: ET 1.64±0.3 pg/ml vs 0.82±0.1 pg/ml (P0.009); A-II 20.8±6.2 pg/ml vs 7.75+2.3 pg/ml (P0.007); TxB2 100.8±17.7 pg/ml vs 40.1±11.7 pg/ml (P0.04); PGI2 638.3±41.1 pg/ml vs 318.3±36.4 pg/ml (P0.001), respectively. At 48 h, a similar pattern of results was obtained as the kidney continued to produce TxB2 and prostacyclins during the 24–48 h period. In the UW solution, basal levels of ET and A-II were lower than those in EC solution, but similarly increased after initial ischemia. At 24 h, the concentrations produced by the left and right kidneys were as follows: ET 0.66±0.1 pg/ml vs 0.48±0.1 pg/ml (P0.14); A-II 10.36±3.7 pg/ml vs 2.14±0.7 pg/ml (P0.006); TxB2 178±53 pg/ml vs 52±23.1 pg/ml (P0.001); and PGI2 448.3±49 pg/ml vs 323±44.3 pg/ml (P0.01), respectively. After 48 h, the range of concentrations of each substance was similar to that obtained after 24 h. In further studies, the concentrations of ET and A-II were measured in solution previously used to preserve human kidneys (n=7). The mean concentration of ET and A-II in these samples was 3.82±1.14 pg/ml and 21.3±9.2 pg/ml, respectively, whereas in control media both substances were below the limits of detection. These results demonstrate that vasoconstrictive substances can be measured in the preservation media after a kidney has been stored cold and that higher concentrations are found when the organ has been subjected to prior normothermic ischemia. The measurement of these vasoactive substances before transplantation may reveal that the kidney has been subjected to previous ischemic events. Moreover, these vasoactive substances could be involved in the early recovery of renal function after kidney transplantation.  相似文献   
6.
BACKGROUND: Helicobacter pylori (H. pylori) infection induces nitric acid (NO) overproduction through inducible NO synthase (NOS) expression, subsequent DNA damage and enhanced antiapoptosis signal transduction sequence in the human gastric mucosa, whereas its possible effect on endothelial nitric oxide synthase (eNOS) expression has not as yet been investigated. The aim of this study was to evaluate the effect of H. pylori infection in the expression of eNOS in gastric mucosa. PATIENTS AND METHODS: We prospectively studied 30 nonsmoking dyspeptic patients (12 men, 18 women, mean age 54.26+/-12.89 years). The diagnosis of H. pylori infection was based mainly on histology. The histological grading of H. pylori infection was evaluated according to the modified Sydney classification. Histological grading of eNOS expression and microvessel density as estimated by CD34 expression were determined by immunohistochemistry (degree 0-3) and correlated with H. pylori infection and histological degree of gastritis. RESULTS: Twelve patients were H. pylori-positive and 18 patients were H. pylori-negative. The two groups were matched for age (P=0.139), sex (P=0.342) and similar degree of gastritis. Intensity of eNOS and CD34 expression in the corpus and antrum were significantly correlated (P<0.001). eNOS expression was correlated with H. pylori infection in the mucosa of the body and antrum (P=0.013 and 0.037, respectively) but not with gastric inflammation and activity (P=0.848 and 0.871, respectively, for the corpus and P=0.565 and 0.793, respectively, for the antrum). H. pylori-positive patients showed higher expression of CD34-positive blood vessels in the mucosa of the antrum (P=0.048). CD34 expression was correlated with gastric inflammation and activity (P=0.03 and 0.044, respectively) in the mucosa of the antrum of H. pylori-positive patients. CONCLUSION: H. pylori infection upregulates eNOS, and induces angiogenesis, contributing to H. pylori-associated pathophysiology in gastric mucosa.  相似文献   
7.
BACKGROUND/AIMS: Primary and metastatic liver tumors are the most common malignancies that resist conventional chemotherapy and radiotherapy. Several immunotherapies have been attempted for cancer treatment on the basis of stimulating host immune response to tumors and recent development of combined targeting locoregional immunochemotherapy reported with promising results. However, the efficacy of this therapeutic modality is not yet widely established. METHODOLOGY: We reviewed the medical literature for publications dealing with the value of locoregional immunochemotherapy in patients with primary or metastatic liver tumors. RESULTS: We found that 5 and 7 studies have been controlled and inadequately controlled, respectively. Among 131 patients with primary liver cancer, 40 were treated with combined locoregional immunochemotherapy, and 20 with systemic immunochemotherapy, and 71 with systemic chemotherapy served as two control groups. Complete or partial response was observed in 32 out of 40 (80%) patients who received combined locoregional therapy, and in 10 out of 20 (50%) systemic immunochemotherapy controls (P = 0.03). Survival was three times higher in the patients who received combined locoregional therapy compared with systemic chemotherapy controls (18 vs. 5.6 months). Recurrence of tumor was higher in systemic immunochemotherapy controls (P = 0.003). Among 286 patients with metastatic liver disease, 180 patients were treated with combined locoregional immunochemotherapy and 106 patients with systemic immunochemotherapy. Response (complete or partial) was observed in 65 out of 98 (66.3%) patients who received combined therapy, and in 4 out of 26 (15.4%) controls (P < = 0.001). Survival was two-fold higher in the patients treated with combined therapy (21 vs. 10.5 months). Tumor recurrence was higher in the systemic immunochemotherapy controls (P < = 0.001). CONCLUSIONS: The observational studies indicate a plausible therapeutic rationale for the introduction of locoregional immunotherapy in patients with primary and metastatic liver disease.  相似文献   
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9.
Koidou  V. P.  Chatzopoulos  G. S.  Tomas  I.  Nibali  L.  Donos  N. 《Clinical oral investigations》2020,24(1):487-502
Clinical Oral Investigations - Surgical treatments such as guided tissue regeneration (GTR) and access flap surgery are widely employed for the treatment of intrabony defects. However, little is...  相似文献   
10.

Aim-Background

Despite the rise in the incidence of breast cancer (BC), a steady increase in the rate of survival has also been noted which can be directly attributed to early diagnosis, among others. Therefore, keeping women informed of the latest advances in BC treatment and prevention is crucial. The aim of this study is an attempt to quantify the level of awareness of Greek women on issues related to female BC prevention.

Methods

An online questionnaire of 24 items divided into three sections (sociodemographic, personal experience, as well as beliefs concerning BC prevention and screening) was completed and submitted anonymously by 2565 Greek women of all adult age groups and of various socioeconomic backgrounds.

Results

Only 42.8% of women used credible sources of information on health issues such as BC. Regular breast self-examination was adopted by one in three women. It emerged that 89% of women erroneously associated in vitro fertilization with an increased risk of BC, while half the women were unaware of the possibility of a false-negative result from breast screening. Low BC awareness was associated with low education, low economic status, younger age, single women from non-urban areas who did not have (or did not know if they had) a BC family history and who usually refrained from any kind of preventive actions.

Conclusions

The study revealed that there is a significant proportion of Greek women with a misperception or ignorance of BC prevention and the significance of early diagnosis. Since timely diagnosis is directly related to BC survival rate, specific actions (e.g. targeted educational interventions in specific subpopulations) should be assumed.
  相似文献   
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