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101.
Bladder cancer accounts for nearly 5% of all newly diagnosed cancers in Jordan, with a much higher frequency in males. Recent studies have shown that activating mutations in FGFR3 are the most common findings in non-invasive low grade bladder tumors. In this study, we, retrospectively, investigated a cohort of 121 bladder cancer patients with various grades and stages of the tumor for molecular changes in FGFR3. Overexpression of FGFR3 was observed in 49%, 34%, 15%, and 2% of pTa, pT1, pT2, and pT3 cases, respectively. Further, FGFR3 expression was positive in 45%, 26%, and 30% of G1, G2 and G3 cases, respectively. Mutational analysis of exons 7, 10 and 15 of FGFR3 identified four previously reported mutations, namely R248C (n = 4; 10%), S249C (n = 23; 59%), Y375C (n = 7; 18%), G382R (n = 4; 10%), and one novel mutation, G382E (n = 1; 3%). Our results indicate that both mutations and overexpression of FGFR3 are correlated together, and are more prevalent in early stage (pTa and pT1) and low grade (G1 and G2) bladder tumors. Survival analysis showed no contribution of changes in FGFR3 on the patient's survival. Multivariate Cox proportional hazards model analysis of overall survival for the following variables: age, gender, stage and grade of tumor, and FGFR3 (expression and mutation) revealed that age, stage and grade of tumor are independent predictors of overall survival in patients with bladder cancer. Our work is the first to address the molecular status of FGFR3 in Jordanian patients with bladder cancer, and provides further support for FGFR3 as a key player in the initiation of bladder tumors.  相似文献   
102.
We previously demonstrated the presence of activated areas in the non-injured contralateral sensorimotor cortex in addition to the ipsilateral sensorimotor cortex of the area surrounding a brain infarction, using a rat model of focal photochemically induced thrombosis (PIT) and functional magnetic resonance imaging. Using this model, we next applied gene expression profiling to screen key molecules upregulated in the activated area. RNA was extracted from the ipsilateral and contralateral sensorimotor cortex to the focal brain infarction and from the sham controlled cortex, and hybridized to gene-expression profiling arrays containing 1,322 neurology-related genes. Results showed that glycine receptors were upregulated in both the ipsilateral and contralateral cortex to the focal ischemic lesion. To prove the preclinical significance of upregulated glycine receptors, kynurenic acid, an endogenous antagonist to glycine receptors on neuronal cells, was administered intrathecally. As a result, the kynurenic acid significantly improved behavioral recovery within 10 days from paralysis induced by the focal PIT (p < 0.0001), as evaluated with beam walking. These results suggest that intrathecal administration of a glycine receptor antagonist may facilitate behavioral recovery during the acute phase after brain infarction.  相似文献   
103.
It is known that ALY/Nsc Jcl-aly/aly (aly/aly) mice that congenitally lack lymph nodes fall victim to Sj?gren syndrome as a function of age. We investigated how TCRint cells of extrathymic origin and TCRhigh cells of thymic origin are distributed in various organs of these mice. Although the distribution of T-cell subsets was not different between control aly/+ and aly/aly mice in youth in any of the tested organs, the proportion of TCRint cells in the liver and spleen of aly/aly mice increased with aging. Usually, TCRint cells in the liver comprise a half-and-half mixture of a NK1. 1(+) subset (i.e., NKT cells) and a NK1.1(-) subset. In constrast, almost all expanding TCRint cells in various immune organs of aly/aly mice were found to be NK1.1(-). A large proportion of lymphocytes, including NK cells and TCRint cells, were also present in the salivary glands of aly/aly mice. Interestingly, these TCRint cells in the salivary glands contained an NK1.1(+) subset (i.e., NKT cells) that used an invariant chain of Valpha14Jalpha281 for TCRalphabeta (>50%). Moreover, gammadeltaT cells that used Vgamma 1, 2, 4/Vdelta 1, 4, 6 mRNAs, different from those of gammadeltaT cells in the liver and intestine, were abundant. Possibly reflecting the in situ generation of these T cells in the salivary glands, the expression of RAG-2 mRNA was evident by the RT-RCR method. These results suggest that (i) inflammatory lymphocytes that evoke Sj?gren syndrome in aly/aly mice are NK cells or TCRint cells (both NK1.1(+) and NK1.1(-) subsets) and (ii) TCRint cells in the salivary glands might be generated in situ.  相似文献   
104.
This study was conducted to characterize enterocyte apical membrane-bound alkaline phosphatase activity in different segments of the porcine small intestine. Duodenal, jejunal, and distal ileal segments were isolated from three 26-kg pigs and enterocyte brush border membrane, enriched between 19- and 24-fold in sucrase specific activity, was prepared by Mg(2+) precipitation and differential centrifugation. With P-nitrophenyl phosphate as substrate, the optimum pH for porcine brush border membrane-bound alkaline phosphatase activity was defined to be 10.5 for all three segments. At the optimal pH, the kinetics of membrane-bound alkaline phosphatase were determined for the three intestinal segments. The affinity of this enzyme (K(m), mM) in the jejunum (0.64 +/- 0.07) was four times greater than that in the duodenum (2.75 +/- 0.59) and the distal ileum (2.71 +/- 1.14). These results indicate that different isomers of membrane-bound alkaline phosphatase might have been expressed in different segments of porcine small intestine. The maximal specific activity (V(max), micromol/mg protein . min) of this enzyme was highest in the duodenal (7.74 +/- 0.95), intermediate in the jejunal (4.31 +/- 0.18), and lowest in the distal ileal (3.53 +/- 0.84) brush border membrane. Therefore, the maximal specific activity of brush border membrane-bound alkaline phosphatase along the intestinal longitudinal axis in growing pigs decreases from the duodenum toward the distal ileum.  相似文献   
105.
When we attempted to characterize the immunological state in G-CSF transgenic mice, a large number of not only granulocytes but also lymphoid cells expanded in various immune organs. Such lymphoid cells were present at unusual sites of these organs, e.g., the parenchymal space in the liver. We then determined the phenotype of these lymphoid cells by immunofluorescence tests. It was demonstrated that CD3intIL-2Rbeta+ cells (i.e., extrathymic T cells), including the NK1.1+ subset of CD3int cells (i.e., NKT cells), increased in the liver and all other tested organs. These T cells as well as NK cells mediated NK and NK-like cytotoxicity, especially at youth. However, they were not able to mediate such cytotoxicity in the presence of granulocytes. This result might be associated with deficiency in the hybrid resistance previously ascribed to these mice. In other words, G-CSF transgenic mice had a large number of extrathymic T cells (including NKT cells) and NK cells that mediate hybrid resistance, but their function was suppressed by activated granulocytes. Indeed, these granulocytes showed an elevated level of Ca2+ influx upon stimulation. The present results suggest that, in parallel with overactivation of granulocytes, extrathymic T cells and NK cells are concomitantly activated in number but that their function is suppressed in G-CSF transgenic mice.  相似文献   
106.
107.
An amperometric dimethyl sulfoxide (DMSO) sensor was constructed based on DMSO reductase (DMSO-R). DMSO-R from Rhodobacter sphaeroides f. sp. denitrificans was immobilized by BSA-glutaraldehyde cross-linking at the surface of a glassy carbon electrode. Mediators were added to the sample solution in a free form. Several mediators (methyl viologen (MV), benzyl viologen (BV), neutral red (NR), safranin T (ST), FMN, phenazine methosulfate (PMS)), which can donate electrons to DMSO-R, were examined with the DMSO-R immobilized electrode. Among them MV was selected as a model mediator because of its wide linear response range and fast response time. The response current was effected by the measurement temperature but hardly effected by the pH of the sample solution. The response current was increased with the measurement temperature up to 50 degrees C. A response current was observed at 1 microM DMSO and the response time was 20 s under the optimum conditions. The response was observed for approximately 2 weeks. By the reduction of Schiff base in the cross-linking layer the response range became narrower but most of the response current was retained at 300 microM of DMSO for more than 5 weeks.  相似文献   
108.
Saccharides including mono- and disaccharides were quantitatively derivatized with 2-aminobenzoic acid (2-AA). These derivatives were then separated by capillary zone electrophoresis with UV detection using 50mM sodium phosphate buffer as the running electrolyte solution. In particular, the saccharide derivatives with the same molecular weight as 2-AA aldohexoses (mannose and glucose) and 2-AA aldopentoses (ribose and xylose) were well separated. The underlying reasons for separation were explored by studying their structural data using 1H and 13C NMR. It was found that the configurational difference between their hydroxyl group at C2 or C3 could cause the difference in Stokes' radii between their molecules and thus lead to different electrophoretic mobilities. The correlation between the electrophoretic behavior of these carbohydrate derivatives and their structures was studied utilizing the calculated molecular models of the 2-AA-labeled mannose, glucose, ribose, and xylose.  相似文献   
109.
Patch-clampexperiments were conducted to study the effects of basal lamina(basement membrane) of preovulatory chicken ovarian follicle onmembrane currents in differentiated chicken granulosa cells in ahomologous system. The membrane capacitance (measure of total membranearea) was smaller in cells cultured on intact basal lamina than that ofcontrol cells. The granulosa cells expressed outward and two inwardcurrents. A small fraction of the cells (3%) expressed only atransient fast-activating and -inactivating inward current carried byCa2+. The majority of the cells, however, expressed aslowly activating and inactivating inward current (carried byCl) that was superimposed on the transientCa2+ current. All cells expressed an outward currentcharacteristic of the delayed-rectifier K+ current. Theremoval of extracellular Ca2+ led to elimination of theslow inward Cl current, indicating that it is aCa2+-dependent Cl current. Both peakamplitude and current density of the inward Cl currentwere significantly lower in cells cultured on freshly isolated intactbasal lamina (or basal lamina stored at 4°C for 12 mo) than those ofcontrol cells; however, basal lamina had no significant effect on thedensity of the outward current. Similar to the observations made forintact basal lamina, solubilized basal lamina suppressed the inwardCl current in differentiated granulosa cells. These datashow that homologous basal lamina modulates aCa2+-dependent Cl current in differentiatedgranulosa cells. These findings provide a partial explanation for themechanisms that subserve the reported effects of basal lamina (basementmembrane) on the metabolic functions of differentiated granulosa cells.

  相似文献   
110.
Our objectives were to determine postnatal changes in the maximal enzyme activity (V(max)) and enzyme affinity (K(m)) of jejunal mucosal membrane-bound alkaline phosphatase, aminopeptidase N and sucrase using a porcine model which may more closely resemble the human intestine. Jejunal brush border membrane was prepared by Mg(2+)-precipitation and differential centrifugation from pigs of suckling (8 days), weaning (28 days), post-weaning (35 days) and adult (70 days) stages. p-Nitrophenyl phosphate (0-8 mM), L-alanine-p-nitroanilide hydrochloride (0-28 mM) and sucrose (0-100 mM) were used in alkaline phosphatase, aminopeptidase N and sucrase kinetic measurements. V(max) of alkaline phosphatase was the lowest in the adult (4.27 micromol.mg(-1) protein.min(-1)), intermediate in the suckling (9.75 micromol.mg(-l) protein.min(-l)) and the highest in the weaning and post-weaning stage (12.83 and 10.40 micromol.mg(-l) protein.min(-l)). K(m) of alkaline phosphatase was high in the suckling and weaning stages (5.14 and 9.93 mM) and low in the adult (0.66 mM). V(max) of aminopeptidase N was low in the suckling (7.04 micromol.mg protein(-1).min(-1)) and high in the post-weaning stage (13.36 micromol.mg(-l) protein.min(-l)). K(m) of aminopeptidase N was the highest in the two weaning stages (2.96 and 3.39 mM), intermediate in the adult (2.33 mM) and the lowest in the suckling stage (1.66 mM). V(max) of sucrase increased from the suckling to the adult (0.48-1.30 micromol.mg(-l) protein.min(-l)). K(m) of sucrase ranged from 11.19 to 16.57 mM. There are dramatic postnatal developmental changes in both the maximal enzyme activity and enzyme affinity of jejunal brush border membrane-bound alkaline phosphatase, aminopeptidase N and sucrase in the pig.  相似文献   
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