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81.
OBJECTIVES: The objectives of this study were to develop a shape-constraint region-growing algorithm to automatically delineate liver metastases on computed tomography images and to compare automated tumor measurements with those outlined manually by radiologists. METHODS: The algorithm starts with a manual selection of a seed lesion region of interest (ROI). Based on intensity distributions of the seed ROI and the liver parenchyma, several parameters are computed and used to adaptively guide the region growing. To prevent the region growing from leaking into surrounding tissues of similar characteristics, specific shape constraints, including a local shape, a global shape, and a gravity-shift index, are developed to jointly control the iteration of the region growing. The algorithm was applied to 59 lesions in 14 patients with liver metastases. The maximal diameter (unidimension), the product of the maximal and maximal perpendicular diameters (bidimension), and the area in the axial plane were calculated for each of the segmented lesions. Three independent radiologists manually measured all the lesions once, and one of the radiologists measured each lesion 3 times. For each measurement, the concordance correlation coefficient (CCC) was used to assess the pairwise agreement between the computer and the different radiologists, and the overall concordance correlation coefficient (OCCC) was used to assess the agreement between the computer and the multiple radiologists and between the one radiologist's 3 readings. RESULTS: Fifty-three of 59 (89.8%) lesions in 14 patients with liver metastases were successfully segmented using this algorithm. The algorithm achieved a median accuracy of 88.0%. CCCs/OCCCs ranged from 0.943 to 0.999 with 95% confidence intervals. CONCLUSIONS: High accuracy and CCCs/OCCCs suggested that measurements made by the computer were very similar to those made by the radiologists.  相似文献   
82.

Background  

To assess the prevalence of nutritional deficiencies amongst people who suffer from morbid obesity and are candidates for bariatric surgery and to evaluate the relations between pre-operative nutritional deficiencies and demographic data and co-morbidities.  相似文献   
83.
Summary It has been previously shown that p43 — a breast cancer associated antigen — has immunosuppressive properties. The present study was carried out in order to elucidate the pathomechanisms of immunosuppression in breast cancer patients influenced by the expression of p43. Lymphocytes were cultured from blood of 29 women with benign lesions in the breast as well as from 41 female patients with breast cancer. Lymphocyte stimulation was performed by addition of Concanavalin (Con A) in cultures with lymphocytes alone (CONLYM) or in lymphocytes incubated with p43 (CONAg). In other series immunomodulation was tried by addition of indomethacin (INDLYM, INDAg), levamisole (LEVLYM, LEVAg), or interleukin-2 (ILLYM, ILAG). In breast cancer patients, addition of p43 significantly inhibited the activation of lymphocyte proliferation by Con A compared to women with benign tumors. The addition of indomethacin or levamisole did not influence this inhibitory effect of p43 in breast cancer patients. Contrary to these observations, addition of IL-2 resulted in increased proliferation of lymphocytes from patients with benign as well as malignant tumors, which was inhibited after addition of p43. Analysis of the correlation of the immunosuppressive properties of p43 in correlation with prognostic factors for breast cancer showed evidence for a stronger activity of p43 in early stage tumors (i.e. smaller than 2 cm, lymph node negative, histologic grading GI), confirming previous observations of a higher expression of p43 in early stages of breast cancer.  相似文献   
84.
The MeOH extracts of the ground part and the root of Boenninghausenia japonica NAKAI showed inhibitory activity against tumor cell growth. Fractionation of the extracts has resulted in isolation of 1,3-dihydroxy-4-(2'-hydroxy-3'-hydroxymethyl-3',4'-epoxy-butyl)-N-methylacridone, 1,3-dihydroxy-4-[(Z)-3'-hydroxy-3'-methyl-buten-1'-yl]-N-methylacridone, 3-(1',1'-dimethylallyl)-7-hydroxy-8-methoxy-2H-1-benzopyran-2-one, casegravol, cis-casegravol, and edgeworin in addition to 9 compounds reported from B. japonica and B. albiflora. The isolates from this plant and some related compounds were tested for antiproliferative activity against human gastric adenocarcinoma (MK-1), human uterus carcinoma (HeLa), and murine melanoma (B16F10) cells.  相似文献   
85.
In this study, dynamics of group-as-a-whole (GAW) moments within children's group therapy were investigated. The children's groups, called Play Activity Groups (PAGs), were a part of the elective activities within an afterschool program. This study included the participation of 17 children and six facilitators from five school age groups. Kinetic drawings from the children, process notes from the facilitators, and semi-structured interviews from both children and facilitators were analyzed as indirect, retrospective, and qualitative data. The study showed that the sequence of events in GAW was related to the ability of the group, and particularly of the adult members, to sustain the role of other, and to withstand the destructive forces of GAW activity. If this task was accomplished, a sense of play, fluidity, and safety were noted by both children and adults. The study was exploratory, and has limited generalizability. The need for research with different groups and methods is presented. The implications for therapists' techniques are discussed.  相似文献   
86.
Human placental isoferritin is composed of a 43 kDa subunit and ferritin light chains. It acts as an immunosuppressive cytokine in normal gestation and in some malignant conditions. We investigated p43-placental isoferritin expression at the maternal fetal tissue interface and in fetal kidneys in Down's syndrome (DS) compared with normal control samples. Following termination of mid-gestation pregnancies placental and fetal kidney tissue samples were collected. Immunohistochemical analysis of the specimens was performed using a monoclonal antibody generated against human p43-placental isoferritin protein (CM-H-9 mAb). Expression of p43-placental isoferritin was detected in Hofbauer cells and in the syncytial layer of placental tissue. Significantly higher numbers of positive Hofbauer cells were detected in DS placentae at 17 weeks gestation compared with the controls. The number of immunopositive Hofbauer cells decreased in DS placentae at 20 weeks gestation, 3 weeks later than in controls. In kidneys of fetuses at 17 weeks gestation, p43-placental isoferritin immunoreactivity was confined to the proximal tubules of the nephrons. DS kidneys had higher staining intensities compared with similar gestational age controls. Enhanced expression of p43-placental isoferritin was observed in DS placentae and fetal kidneys. This may explain the increased p43-placental isoferritin levels in the maternal serum of DS gestations.  相似文献   
87.
The potential use of the ferritin bearing lymphocytes (FBL) blood test which enumerates oncofetal FBL as a biomarker for early breast cancer was explored. Analysis of the FBL positive test results carried out on high risk women who underwent biopsy in 1983–84 was found to be a significant predictor for early breast cancer (relative risk (RR) = 2.9, 95% confidence interval (CI) 1.4-5.8). A group of 635 women from the above study diagnosed in 1983-84 as having no evidence of breast cancer was further traced 8 years later with the aid of the National Cancer Registry. We identified 35 malignancies, including 19 cases of breast cancer. The RR of breast cancer for the FBL positive group was 2.51; 95% CI = 1.04-6.07 while for the other malignancies it was 0.93, 95% CI = 0.30-2.84. All the breast cancer cases in the FBL positive group were of the infiltrative duct carcinoma category and 71% were in early stage. In contrast, in the FBL negative group, 60% of the cases were infiltrative ductal carcinoma and most of them were at stage III. Positive FBL is associated with early manifestation of breast cancer and may be considered as a tool for the screening of breast cancer in high risk women.  相似文献   
88.
Nerve growth factor (NGF) is a well-known neurotrophic factor acting on both the peripheral and the central nervous systems. In addition, it has been shown to play a role in the function of the immune system through specific receptors. Both high-affinity and low-affinity NGF receptors (NGFR) are expressed on human B lymphocytes. The low-affinity NGFR has been shown to have structural homology with another specific B cell surface molecule, CD40, which plays an important role in IgE production. In view of the structural similarities of the p75 NGFR and CD40 we examined whether NGF may also be involved in the regulation of IgE production. We found that NGF and anti-CD40 exerted opposite effects on the induction of IgE by IL-4 in peripheral blood mononuclear cells. NGF inhibited the induction of IgE by IL-4 and this inhibition was not mediated through blocking of the induction of CD23 nor through inhibition of IL-4R expression. The inhibition of IL-4-dependent IgE production was observed on surface (s)IgE+ and sIgE?/sIgM+ B lymphocytes. Anti-CD40 on the other hand, exerted an enhancing effect on IgE production and its addition to IL-4 provided a signal that was resistant to the inhibitory effect of NGF. Antagonistic effects of NGF and IL-4 were also observed for other Ig isotypes since IL-4 prevented the increase in IgA and IgM production induced by NGF. These data indicate that although NGFR and CD40 belong to the same receptor super-family and exert similar proliferative effects on B lymphocytes, they interact differently with IL-4 in the regulation of IgE production.  相似文献   
89.
Nerve growth factor (NGF) plays an important role in the regulation of the immune system. Recent studies from this laboratory demonstrated the presence of functional NGF receptors on human B lymphocytes; in addition, NGF has been shown to enhance B lymphocyte proliferation. NGF caused both concentration- and time-dependent increases in tyrosine phosphorylation of five proteins of 140, 110, 85, 60 and 42 kDa, which were identified as phospholipase C-γ1, phosphatidylinositol-3 kinase and mitogen-activated protein kinase. To elucidate the contribution of the Trk family of tyrosine kinases to the phosphorylation events induced by NGF, we identified gp140trk in human B cells and in human B cell lines. Analysis of specific gp140trk immunoprecipitates indicated that addition of NGF to B cells induced a rapid increase in the tyrosine phosphorylation of gp140trk and inhibition of this phosphorylation prevented the tyrosine phosphorylation of other proteins. These data identify the central role of gp140trk in NGF signaling of human B lymphocytes.  相似文献   
90.
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