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1.
Ultrasound bladder vibrometry (UBV) parameters have been shown in previous studies to strongly correlate with measurements from urodynamic studies. Just like urodynamic studies, UBV can be performed in supine and sitting positions. The objective of this study is to compare UBV parameters obtained in the two different positions using statistical methods. We recruited eight volunteers with healthy bladders for this purpose. The elasticity, group velocity squared and thickness of the bladder were the UBV parameters of interest, and their values were recorded at different bladder volumes for each volunteer. The results presented indicate that the measurements made in the two positions are in agreement using the Bland–Altman method and a parameter q which compares the values at each bladder volume for each volunteer. UBV parameters were also repeatable for measurements recorded in the supine and sitting positions.  相似文献   
2.

Purpose

Transamniotic stem cell therapy (TRASCET) with select mesenchymal stem cells (MSCs) has been shown to induce partial or complete skin coverage of spina bifida in rodents. Clinical translation of this emerging therapy hinges on its efficacy in larger animal models. We sought to study TRASCET in a model requiring intra-amniotic injections 60 times larger than those performed in the rat.

Methods

Rabbit fetuses (n?=?65) with surgically created spina bifida were divided into three groups. One group (untreated) had no further manipulations. Two groups received volume-matched intra-amniotic injections of either saline or a concentrated suspension of amniotic fluid MSCs (afMSCs) at the time of operation. Infused afMSCs consisted of banked heterologous rabbit afMSCs with mesenchymal identity confirmed by flow cytometry, labeled with green fluorescent protein. Defect coverage at term was blindly categorized only if the presence of a distinctive neoskin was confirmed histologically. Statistical comparisons were by logistic regression and the likelihood ratio test.

Results

Among survivors with spina bifida (n?=?19), there were statistically significant higher rates of defect coverage (all partial) in the afMSC group when compared with the saline and untreated groups (0–50%; p?=?0.022–0.036), with no difference between the saline and untreated groups (p?=?1.00). Donor afMSCs were identified locally, though sparsely and not in the neoskin.

Conclusions

Concentrated intra-amniotic injection of amniotic mesenchymal stem cells can induce partial coverage of experimental spina bifida in a leporine model. Transamniotic stem cell therapy may become a feasible strategy in the prenatal management of spina bifida.

Level of Evidence

N/A (animal and laboratory study).  相似文献   
3.
4.
5.

Purpose

We sought to examine donor mesenchymal stem cell (MSC) kinetics after transamniotic stem cell therapy (TRASCET) in experimental spina bifida.

Methods

Pregnant Sprague–Dawley dams exposed to retinoic acid for the induction of fetal neural tube defects received volume-matched intra-amniotic injections on gestational day 17 (E17; term = E22): either amniotic fluid MSCs (afMSCs) labeled with a luciferase reporter gene (n = 78), or luciferase protein alone (n = 66). Samples from twelve organ systems from each surviving fetus with spina bifida (total n = 60) were screened via microplate luminometry at term.

Results

Donor afMSCs were identified exclusively in the placenta, umbilical cord, spleen, bone marrow, hip bones, defect, and brain. Luminometry was negative in control fetuses receiving luciferase alone (p < 0.001). Signal intensity in relative light units (RLUs) was moderately correlated between the defect and the hip bones (rho = 0.38, p = 0.048), and between the placenta and the brain (rho = 0.40, p = 0.038).

Conclusions

Amniotic mesenchymal stem cells engraft to specific sites after concentrated intra-amniotic injection in the setting of spina bifida. A hematogenous route encompassing the bone marrow as well as distant central nervous system homing are fundamental constituents of cell trafficking. These findings must be considered during eventual patient selection for transamniotic stem cell therapy in the prenatal management of spina bifida.  相似文献   
6.
Context: Vinoreline is a vinca alkaloid anticancer drug widely used in cancer therapy. Drugs are not target specific, therefore might affect normal tissues/cells, in which bone marrow is the important one. Objective: To elucidate the cytotoxic and genotoxic effect of vinca alkaloid anti cancer drug, vinorelbine, on mice non-adherent bone marrow cells in vitro. Materials and methods: Non-adherent bone marrow cells were isolated and exposed to various concentrations (0–160?µg/ml) for 4?h at 23?°C. The chromatin proteins were analyzed by SDS PAGE and western blot. Fluorescent dye staining of the cells, anion superoxide and DNA fragmentations assays were also employed. Result: The results from MTT and trypan blue exclusion assays represented reduction of the cells viability. Extractability of histones and HMG proteins contrasted with difficulty as their content was decreased on SDS-gel upon increasing drug concentration as western blots confirmed it. The amount of degradation form of PARP (89?KD) increased significantly in a dose dependent manner. Increase in anion superoxide production and DNA fragmentation together with cytological detection of chromatin condensation and cellular damage upon exposure of the cells to vinorelbine were indicative of apoptosis induction in these normal cells. Conclusion: Vinorelbine is genotoxic in non-adherent bone marrow cells as affects chromatin components, DNA, histone and HMGB1 proteins and induces apoptosis.  相似文献   
7.
Numerous pathogens, including Mycobacterium tuberculosis, can activate human γ9δ2 T cells to proliferate and express effector mechanisms. γ9δ2 T cells can directly inhibit the growth of intracellular mycobacteria and may also act as antigen-presenting cells (APC). Despite evidence for γδ T cells having the capacity to function as APC, the mechanisms involved and importance of these effects on overall tuberculosis (TB) immunity are unknown. We prepared M. tuberculosis-specific γ9δ2 T cell lines to study their direct protective effects and APC functions for M. tuberculosis-specific αβ T cells. The direct inhibitory effects on intracellular mycobacteria were measured, and the enhancing effects on proliferative and effector responses of αβ T cells assessed. Furthermore, the importance of cell-to-cell contact and soluble products for γ9δ2 T cell effector responses and APC functions were investigated. We demonstrate, in addition to direct inhibitory effects on intracellular mycobacteria, the following: (i) γ9δ2 T cells enhance the expansion of M. tuberculosis-specific αβ T cells and increase the ability of αβ T cells to inhibit intracellular mycobacteria; (ii) although soluble mediators are critical for the direct inhibitory effects of γ9δ2 T cells, their APC functions do not require soluble mediators; (iii) the APC functions of γ9δ2 T cells involve cell-to-cell contact that is dependent on CD40-CD40 ligand (CD40L) interactions; and (iv) fully activated CD4+ αβ T cells and γ9δ2 T cells provide similar immune enhancing/APC functions for M. tuberculosis-specific T cells. These effector and helper effects of γ9δ2 T cells further indicate that these T cells should be considered important new targets for new TB vaccines.  相似文献   
8.
A term Caucasian male infant, born to a healthy non-related couple, was noted at birth to have bilateral edema and bluish discoloration of the lower eyelids. On physical examination, the eye globes were not visualized and hypertelorism was noted. Radiological imaging revealed large bilateral orbital cysts, microphthalmos, and severe optic nerve hypoplasia. Histological study of the excised orbital masses showed cysts lined by primitive, immature retinal tissue which contained neuroglial elements and scattered dysplastic rosettes. Chromosome analysis revealed an apparent balanced reciprocal translocation between the long arm of chromosome 3 and 5, i.e. 46, XY, t (3; 5) (q27; q11.2).Chromosome studies in parents were normal. To our knowledge, the association of this balanced translocation and microphthalmos with cyst has not been previously described in the English literature.  相似文献   
9.
Bacteria comprise an important part of the aquatic microbial flora and perform myriad of ecological roles in aquatic ecosystems. Yet the bacteriological studies on aquatic ecosystems are scarce, especially in the Himalayan context. The main objective of present study was to assess the bacteriological composition of Manasbal lake, the deepest freshwater lake of Kashmir Himalayas, in relation to anthropogenic pressures. The authors measured abundance of the culturable bacteria in lake waters from March to December 2011 using culture based approaches. A total of 1391 different colonies of the identified bacterial strains were obtained from the lake waters with significant site specific variability. The data indicated that the colony number was highest for site II (surrounded by residential hamlets) followed by site I (an irrigational stream) and III (Central site) and lowest for site IV (Outlet). The strains were identified using the gram’s staining, motility test and biochemical tests. Data revealed a highest percentage occurrence of 14.67 % for Proteus II and lowest of 0.21 % for Shigella I. This study indicated the need for development of a feasible system with regular assessment of microbial population for ascertaining the proper microbial load in order to effectively combat the multiple dangers of anthropogenic pollution of the lake.  相似文献   
10.
Little attention has been paid to the effectiveness of hypnosis in improving the results of surgery in Iran. One hundred and twenty patients scheduled for laparoscopic cholecystectomy were randomly divided into either control (standard care) or experimental (hypnosis) groups. Prior to surgery and again after surgery, abdominal pain, nausea, and vomiting were assessed. The results suggest that hypnosis could effectively reduce pain after laparoscopic cholecystectomy and significantly reduce hospitalization time.  相似文献   
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