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1.
OBJECTIVE: The aim of this study was to evaluate the usefulness of measurement of the angle between bilateral renal pelves on axial views in the prenatal ultrasonographic diagnosis of horseshoe kidney. METHODS: We retrospectively measured the renal pelvic angle in 19 fetuses with horseshoe and 20 fetuses with normal kidneys in the second and third trimesters. Renal pelvic angle was defined as the angle between the long axis of the renal pelves on the axial view of the abdomen. We compared the renal pelvic angles of horseshoe and normal kidneys with unpaired t-test. Taking 140 degrees as a cut-off value, we calculated the sensitivity, specificity and accuracy of pelvic angle measurement for the prenatal diagnosis of horseshoe kidney. RESULTS: The mean pelvic angles in the fetuses with horseshoe kidney were 116 degrees and 110 degrees in the second and third trimester, respectively. In the normal fetuses, the equivalent angles were 172 degrees and 161 degrees. The difference between the two groups was statistically significant (P < 0.01). Using 140 degrees as the discriminating criterion, the sensitivity, specificity and accuracy of renal pelvic angle measurement for the prenatal diagnosis of horseshoe kidney were all 100%. Fifteen of 19 fetuses with horseshoe kidney had no other abnormality. Four (21%) fetuses had severe complex abnormalities which were associated with trisomy 18 in three cases. CONCLUSION: Observation and measurement of the renal pelvic angle is a simple and useful method in the prenatal diagnosis of the horseshoe kidney.  相似文献   
2.
Angiogenesis is an independent prognostic indicator in breast cancer. In this report, the relationship between expression of vascular endothclial growth factor (VEGF; a selective mitogen for endothelial cells) and the microvessel density was examined in 103 primary breast cancers. The expression of VEGF was evaluated by immunocytochemical staining using anti-VEGF antibody. The microvessel density, which was determined by immunostaining for factor VIII antigen, in VEGF-rich tumors was clearly higher than that in VEGF-poor tumors ( P <0.01). There was a good correlation between VEGF expression and the increment of microvessel density. Furthermore, postoperative survey demonstrated that the relapse-free survival rate of VEGF-rich tumors was significantly worse than that of VEGF-poor tumors. It was suggested that the expression of VEGF is closely associated with the promotion of angiogenesis and with early relapse in primary breast cancer.  相似文献   
3.
The case of a 52-year-old Japanese man with bronchial granular cell tumors with osteopontin and osteonectin expression is reported here because there have been few investigations of their expression in benign tumors. He was admitted because of sudden hematemesis. A bronchoscopic examination revealed a lobulated polypoid tumor located in the left and right bronchi. Histologically, most tumor cells had abundant granular eosinophilic cytoplasm and were immunoreactive for S-100, neuron-specific enolase (NSE), CD68 and vimentin. Moreover, osteopontin-positive tumor cells were randomly distributed in the tumor tissue, but few stromal cells were positive. In contrast, osteonectin was mainly expressed in the peripheral tumor cells and was also distributed in the stromal cells. Blood vessels at the tumor border in which osteonectin-positive tumor cells were distributed, proliferated moderately. These results suggest that osteopontin and osteonectin may play a role in the progression of granular cell tumors and in the interaction between the tumor and host or angiogenesis around the tumor, respectively.  相似文献   
4.
A fetus with lobar holoprosencephaly and lumbosacral meningomyelocele associated with duplication of the short arm of chromosome 3 is reported. The anomalies were detected on fetal ultrasound at 20 weeks' gestation and the autopsy findings correlated well with the prenatal findings. The fetal karyotype was 46,XY,der(3)del(3)(p26) dup(3)(p26p21.3). The association of holoprosencephaly with duplication 3p is well known, but to the best of our knowledge this is the first reported association of meningomyelocele with 3p duplication. These findings suggest that a gene or genes with a crucial role in central nervous system development are located on the short arm of chromosome 3.  相似文献   
5.
Transgenic rat model of Huntington's disease   总被引:12,自引:0,他引:12  
Huntington's disease (HD) is a late manifesting neurodegenerative disorder in humans caused by an expansion of a CAG trinucleotide repeat of more than 39 units in a gene of unknown function. Several mouse models have been reported which show rapid progression of a phenotype leading to death within 3-5 months (transgenic models) resembling the rare juvenile course of HD (Westphal variant) or which do not present with any symptoms (knock-in mice). Owing to the small size of the brain, mice are not suitable for repetitive in vivo imaging studies. Also, rapid progression of the disease in the transgenic models limits their usefulness for neurotransplantation. We therefore generated a rat model transgenic of HD, which carries a truncated huntingtin cDNA fragment with 51 CAG repeats under control of the native rat huntingtin promoter. This is the first transgenic rat model of a neurodegenerative disorder of the brain. These rats exhibit adult-onset neurological phenotypes with reduced anxiety, cognitive impairments, and slowly progressive motor dysfunction as well as typical histopathological alterations in the form of neuronal nuclear inclusions in the brain. As in HD patients, in vivo imaging demonstrates striatal shrinkage in magnetic resonance images and a reduced brain glucose metabolism in high-resolution fluor-deoxy-glucose positron emission tomography studies. This model allows longitudinal in vivo imaging studies and is therefore ideally suited for the evaluation of novel therapeutic approaches such as neurotransplantation.  相似文献   
6.
Hepatocyte growth factor (HGF) is a mesenchyme- or stroma-derived multipotent factor that regulates the growth, motility, and morphogenesis of various types of cells, including cancer cells. We investigated the effect of HGF on human breast cancer cells, and measured the concentration of HGF in the sera of breast cancer patients. When BT-20 cells were stimulated with HGF, the transmigration of cancer cells was markedly accelerated. In a checkboard assay, pronounced chemotaxic locomotion of BT-20 cells is expressed, corresponding to HGF concentrations. HGF treatment of BT-20 cells resulted in enhanced expression of alpha 2, alpha 3 and beta 1 integrin subunits, and augmented the binding activity to immobilized collagen. The c-met protein was expressed on the cancer cells in 48 of the 97 (49.5%) breast cancer primary tumors. In the serum, the advanced and recurrent cancer group showed a high level of this protein in comparison with the other patient groups. The mean value of serum HGF was 0.65 ng/ml in patients with distant metastases and 0.27 ng/ml in those with no such evidence. Thus, the HGF concentration becomes significantly elevated in the sera of patients with distant metastases. These findings suggest that HGF is involved in invasion and metastasis of breast cancer, and that serum HGF is useful as a tumor marker with a close correlation to the metastatic state of breast cancer.  相似文献   
7.
The preventive effect of purified cell wall of Bifidobacterium infantis, Whole Peptidoglycan (WPG), on the occurrence of mammary tumor induced by 7,12-dimethylbenz(a)anthracene (DMBA) in SD strain female rats was investigated. Rats were given p.o. with 20 mg of DMBA and then received s.c. 200 mu g of WPG weekly for 20 weeks starting on the day of DMBA administration or for 22 weeks, 2 weeks prior to DMBA administration. In the control group, the first tumors appeared 9 weeks after DMBA administration and the cumulative tumor incidence reached 100% within 17 weeks. Subcutaneous injections with WPG weekly for 20 or 22 weeks significantly protected animals from tumor development. The final tumor incidence in the WPG-treated groups was 60-72% at 20 weeks following DMBA administration. On the other hand, WPG was not effective on the delay of the date of first tumor appearance and the growth of tumors once developed. These results suggest that the preventive effect of WPG on the tumor development greatly depends upon the physiological conditions of the hosts in the system of DMBA-SD female rats.  相似文献   
8.
BACKGROUND: To compare the efficacy, safety and tolerability of letrozole, an advanced non-steroidal aromatase inhibitor, and fadrozole hydrochloride, an older-generation drug in this class, we conducted a randomised double-blind trial in postmenopausal women with advanced breast cancer. PATIENTS AND METHODS: One hundred and fifty-seven postmenopausal women with advanced breast cancer were enrolled and randomly assigned to receive letrozole or fadrozole in a multicentre, randomised double-blind trial in Japan. One hundred and fifty-four eligible patients were treated with either letrozole 1.0 mg once daily (n = 77) or fadrozole 1.0 mg twice daily (n = 77), for a minimum of 8 weeks. RESULTS: Letrozole showed a significantly higher overall objective response rate [complete response (CR) + partial response (PR)] than fadrozole (31.2% and 13.0%, respectively; P = 0.011, Fisher's exact test). Clinical benefits defined as CR, PR and stable disease (no change in status for more than 24 weeks) were also higher in patients treated with letrozole (50.6%) than fadrozole (35.1%). Letrozole was significantly superior to fadrozole in terms of the dominant lesion in soft tissue, bone and viscera (P = 0.011, stratified Mantel-Haenszel test). Median time to progression was 211 days in the letrozole group and 113 days in the fadrozole group with no significant difference (P = 0.175, log-rank test). Letrozole markedly reduced the estradiol, estrone and estrone sulfate levels in peripheral blood within 4 weeks. The suppressive effect of fadrozole on these hormone levels was insufficient. Adverse drug reactions were observed in 35.9% of the patients treated with letrozole and in 39.5% of those treated with fadrozole with no significant difference between the two groups (P = 0.74, Fisher's exact test). Most of the adverse drug reactions were rated as grade 1 or 2. CONCLUSIONS: The results show letrozole at a dose of 1.0 mg once daily to be more effective in treating postmenopausal women with advanced breast cancer than fadrozole at 1.0 mg twice daily, with similar safety and tolerability profiles.  相似文献   
9.
PURPOSE: We compared the therapeutic usefulness of doxifluridine (5'-DFUR) alone and a combination of 5'-DFUR plus cyclophosphamide (CPM), both of which are considered effective against advanced and recurrent breast cancer, to determine which treatment is more beneficial as postoperative adjuvant chemotherapy. PATIENTS AND METHODS: A total of 1,131 women with node-positive primary breast cancer were randomly assigned after primary surgery to receive 5'-DFUR alone or 5'-DFUR plus CPM. All patients initially received 5'-DFUR in an oral dose of 1,200 mg/d for 4 weeks, starting 4 weeks after surgery. Chemotherapy was then not given for 2 weeks. Patients in the 5'-DFUR group subsequently received five 4-week cycles of treatment consisting of oral 5'-DFUR (1,200 mg/d) for the first 2 weeks and no chemotherapy for the next 2 weeks. Those assigned to the 5'-DFUR plus CPM group also received oral CPM 100 mg/d for the first 2 weeks and no chemotherapy for the next 2 weeks. Women 50 years or older concurrently received 20 mg/d of tamoxifen for 2 years in both groups. RESULTS: Of the 1,088 eligible women, 546 were assigned to receive 5'-DFUR alone and 542 were assigned to receive 5'-DFUR plus CPM. Overall disease-free survival was significantly better in women who received 5'-DFUR plus CPM than in those who received 5'-DFUR alone (log-rank test, P =.021). Toxic effects occurred in 20.0% of patients (109 of 546) in the 5'-DFUR group and 32.3% of patients (175 of 542) in the 5'-DFUR plus CPM group (chi(2) test, P <.001). CONCLUSION: Combination therapy with 5'-DFUR plus CPM is more effective in preventing recurrence than 5'-DFUR alone.  相似文献   
10.
We previously designed and synthesized the new nuclear factor kappaB (NF-kappaB) inhibitor dehydroxymethylepoxyquinomicin (DHMEQ) derived from the structure of the antibiotic epoxyquinomicin C. We looked into the effect of DHMEQ on cellular phenotypes and tumor growth in mice injected with human breast carcinoma cell line MDA-MB-231 or MCF-7. In estrogen-independent breast adenocarcinoma cell line MDA-MB-231, NF-kappaB is constitutively activated. The addition of DHMEQ (10 microg/mL) completely inhibited the activated NF-kappaB for at least 8 hours. On the other hand, NF-kappaB is not activated in estrogen-dependent MCF-7 cells. In this cell line, DHMEQ completely inhibited the tumor necrosis factor-alpha-induced activation of NF-kappaB. DHMEQ did not inhibit the degradation of IkappaB but inhibited the nuclear translocation of NF-kappaB by both p65/p50 and RelB/p52 pathways. MDA-MB-231 cells secrete interleukin (IL)-6 and IL-8 without stimulation, and DHMEQ decreased the secretion levels of both cytokines. When MDA-MB-231 or MCF-7 cells were stimulated by tumor necrosis factor-alpha, the inhibitory effects of DHMEQ were still maintained. I.p. administration of DHMEQ (thrice a week) significantly inhibited the tumor growth of MDA-MB-231 (12 mg/kg) or MCF-7 (4 mg/kg) in severe combined immunodeficiency mice. No toxicity was observed during the experiment, including the loss of body weight. An immunohistological study on resected MCF-7 tumors showed that DHMEQ inhibited angiogenesis and promoted apoptosis. Furthermore, in Adriamycin-resistant MCF-7 cells highly expressing multidrug resistance gene-1, DHMEQ also exhibited the above capability, including down-regulation of IL-8. Thus, DHMEQ might be a potent drug for the treatment of various breast carcinomas by inhibiting the NF-kappaB activity.  相似文献   
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