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101.
The previous study showed that both valproic acid (VPA) and a bedridden state decreased the serum uric acid level, and VPA-induced renal tubular dysfunction was suspected to be one cause of hypouricemia in severely disabled children. However, it was uncertain what factor of bedridden state influences the uric acid level in severely disabled children. Among many factors of a bedridden state that might influence the uric acid level, we examined the influence of elemental nutrition on the serum uric acid level in severely disabled children because many severely disabled children with marked hypouricemia receive elemental nutrition. Thirty-one severely disabled children were included in this study, who were divided into two groups-group A: 11 patients with elemental nutrition; group B: 20 patients with non-elemental nutrition. The laboratory data in both groups were analyzed statistically, using the t-test. The uric acid level was significantly decreased in group A compared with group B (p < 0.01) without elevation of urinary excretion of uric acid. Other laboratory data, except phosphate and potassium, did not differ between the two groups significantly. An elemental diet may be one factor that decreases the uric acid level in severely disabled children.  相似文献   
102.
103.
Miwa H  Kubo T  Morita S  Nakanishi I  Kondo T 《Neuroreport》2004,15(6):1039-1044
The present study aims to study sequential alterations occurring in both dopaminergic neurons and microglia in substantia nigra (SN) following intrastriatal injection of 1-methyl-4-phenylpridium ion (MPP+) in rats. Heme oxygenase-1 (HO-1), a marker of oxidative stress, first appeared in dopaminergic neurons in SN at 1 day post-lesion. Subsequently, microglia in SN exhibited morphological changes indicative of activation. At 7 days post-lesion, those findings increased severity and 7a significant reduction in the number of dopaminergic neurons was observed. The present finding suggests that extensive oxidative stress and secondary-induced neuroinflammation play a relevant role in MPP(+)-induced retrograde dopaminergic neuron degeneration. We hope that this model will be useful in developing a disease modifying therapy of Parkinson's disease.  相似文献   
104.
Th1 cells play an important role in the pathogenesis of multiple sclerosis (MS), a disease likely linked to an autoimmune process. We measured the levels of chemokines in serum or cerebrospinal fluid (CSF) samples by ELISA, and also studied the expression of Th1-related CXCR3/CCR5 chemokine receptors and Th2-related CCR4/CCR3 chemokine receptors on blood cells from MS patients using three-color flow cytometry. The Bonferroni correction was used for the statistical analysis. The levels of CXCL10, CCL3, and CCL5 in the CSF samples for the MS groups were significantly higher than those for the control group. However, the levels of CCL2 in both the CSF and serum samples for the remission group were significantly higher than those for the active group. The percentage of CXCR3-expressing CD4+ T cells in patients with MS was significantly elevated compared with the healthy controls. Moreover, MS patients in an active phase showed a more increased CD4+CXCR3+/CD4+CCR4+ ratio than patients in a remission phase. The increased percentage of CD4+CXCR3+ cells in the blood was associated with relapses in MS. This study suggested that the CD4+CXCR3+/CD4+CCR4+ ratio could be a sensitive maker of immune dysfunction in MS.  相似文献   
105.
The effect of conjugated docosahexaenoic acid (CDHA) on the inhibition of colon cancer cell growth was examined in the colo 201 human colon cancer cell line, and the effect was compared with docosahexaenoic acid (DHA) and eicosapentaenoic acid (EPA). CDHA was a more potent tumor cell growth inhibitor than DHA and EPA by colorimetric 3-(4,5-dimethylthiazol-2-yl)-5-(3-carboxymethoxyphenyl)-2-(4-sulfophenyl)-2H-tetrazolium (MTS) assay (IC50 for 72 h: 31.6 microM, 46.8 microM, and 56.6 microM, respectively). CDHA inhibited cell cycle progression, due to accumulation of cells in G1 phase, which involved increased p21Cip1/Waf1 and decreased cyclin D1, cyclin E, and proliferating cell nuclear antigen expression; the p53 and cyclin A levels were unchanged. Induction of apoptosis was confirmed by the appearance of sub-G1 populations, and apoptosis cascade involved upregulation of the apoptosis-enhancing proteins (Bak and Bcl-xS) and downregulation of the apoptosis-suppressing proteins (Bcl-xL and Bcl-2). CDHA modulated cell cycle regulatory proteins and apoptosis-related proteins, similar to the effects of DHA. CDHA at a dietary dose of 1.0% significantly inhibited growth of colo 201 cells transplanted in nude mice.  相似文献   
106.

Introduction

The present study was conducted to examine the effect of conjugated docosahexaenoic acid (CDHA) on cell growth, cell cycle progression, mode of cell death, and expression of cell cycle regulatory and/or apoptosis-related proteins in KPL-1 human breast cancer cell line. This effect of CDHA was compared with that of docosahexaenoic acid (DHA).

Methods

KPL-1 cell growth was assessed by colorimetric 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay; cell cycle progression and mode of cell death were examined by flow cytometry; and levels of expression of p53, p21Cip1/Waf1, cyclin D1, Bax, and Bcl-2 proteins were examined by Western blotting analysis. In vivo tumor growth was examined by injecting KPL-1 cells subcutaneously into the area of the right thoracic mammary fat pad of female athymic mice fed a CDHA diet.

Results

CDHA inhibited KPL-1 cells more effectively than did DHA (50% inhibitory concentration for 72 hours: 97 μmol/l and 270 μmol/l, respectively). With both CDHA and DHA growth inhibition was due to apoptosis, as indicated by the appearance of a sub-G1 fraction. The apoptosis cascade involved downregulation of Bcl-2 protein; Bax expression was unchanged. Cell cycle progression was due to G0/G1 arrest, which involved increased expression of p53 and p21Cip1/Waf1, and decreased expression of cyclin D1. CDHA modulated cell cycle regulatory proteins and apoptosis-related proteins in a manner similar to that of parent DHA. In the athymic mouse system 1.0% dietary CDHA, but not 0.2%, significantly suppressed growth of KPL-1 tumor cells; CDHA tended to decrease regional lymph node metastasis in a dose dependent manner.

Conclusion

CDHA inhibited growth of KPL-1 human breast cancer cells in vitro more effectively than did DHA. The mechanisms of action involved modulation of apoptosis cascade and cell cycle progression. Dietary CDHA at 1.0% suppressed KPL-1 cell growth in the athymic mouse system.  相似文献   
107.
The relationship between secretion of parathyroid hormone (PTH) and biologic characteristics, including cell proliferation or monoclonality, is not yet fully understood. To evaluate secretory activity of glands or nodules histopathologically, we focused on the co-expression of chromogranin A (CgA) and parathyroid hormone (PTH) in each gland or nodule. A total of 55 glands from 38 patients with normal parathyroid glands, hyperplastic glands (diffuse and nodular) and primary adenomas were compared. Co-expression of PTH and CgA was decreased to 44.4% in diffuse hyperplastic glands, and to 39.6% in 91 hyperplastic nodules, in contrast to normal glands and primary adenomas that showed constant co-expression of PTH and CgA. Immunohistochemical study of PTH showed a coarse granular pattern predominantly in PTH-positive/CgA-positive nodules, and a dot-like pattern mainly in PTH-positive/CgA-negative nodules. Laser scanning microscopy and immunoelectron microscopy confirmed that a dot-like pattern is based on a positive reaction of PTH at the Golgi apparatus. MIB-1 LI was 12.6 +/- 11.6 in PTH-positive/CgA-positive, and 19.3 +/- 27.3 in PTH-positive/CgA-negative nodules. In conclusion, a combination of PTH and CgA could provide more information about the physiologic state of secretory activity of each nodule than does the simple observation of PTH immunoreactivity.  相似文献   
108.
OBJECTIVE: The objective of this study was to investigate the predictive factors of premature rupture of the membranes (preterm PROM). METHODS: The study was undertaken with cervical secretions collected from 72 consenting singleton pregnant women between 20 and 33 weeks of gestation. The levels of interleukin (IL) 1alpha, IL-1beta, IL-6, IL-8, matrix metalloproteinase (MMP) 1, MMP-2, MMP-9, tissue inhibitors of matrix metalloproteinase (TIMP) 1, TIMP-2, granulocyte elastase, and fetal fibronectin in cervical diluted specimens were measured by immunoassay, and the uterine cervix was assessed by transvaginal ultrasonography. Demographic, obstetric, clinical, neonatal, and laboratory data were analyzed by univariate analysis, multiple logistic regression, and receiver operator characteristic curve analysis. RESULTS: Preterm PROM occurred in 6 women, and 63 women delivered at term. Multiple logistic regression analysis indicated a significant independent association with preterm PROM for the cervical IL-6 levels and cervical length. The receiver operator characteristic curve analysis revealed that an IL-6 level of >/=240 pg/ml in cervical secretions and a cervical length of 相似文献   
109.
110.
We recently reported that Ascaris suum mitochondria express stage-specific isoforms of complex II: the flavoprotein subunit and the small subunit of cytochrome b (CybS) of the larval complex II differ from those of adult enzyme, while two complex IIs share a common iron-sulfur cluster subunit (Ip). In the present study, A. suum larval complex II was highly purified to characterize the larval cytochrome b subunits in more detail. Peptide mass fingerprinting and N-terminal amino acid sequencing showed that the larval and adult cytochrome b (CybL) proteins are identical. In contrast, cDNA sequences revealed that the small subunit of larval cytochrome b (CybS(L)) is distinct from the adult CybS (CybS(A)). Furthermore, Northern analysis and immunoblotting showed stage-specific expression of CybS(L) and CybS(A) in larval and adult mitochondria, respectively. Enzymatic assays revealed that the ratio of rhodoquinol-fumarate reductase (RQFR) to succinate-ubiquinone reductase (SQR) activities and the K(m) values for quinones are almost identical for the adult and larval complex IIs, but that the fumarate reductase (FRD) activity is higher for the adult form than for the larval form. These results indicate that the adult and larval A. suum complex IIs have different properties than the complex II of the mammalian host and that the larval complex II is able to function as a RQFR. Such RQFR activity of the larval complex II would be essential for rapid adaptation to the dramatic change of oxygen availability during infection of the host.  相似文献   
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