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31.
Genomic DNA from 19 Japanese patients with congenital lipoid adrenal hyperplasia (lipoid CAH) representing 16 different families was examined to identify the genetic alterations of steroidogenic acute regulatory protein (StAR). Ten of 19 patients had a 46,XX karyotype and nine had a 46,XY karyotype. Six of the 46,XX patients have experienced spontaneous pubertal changes including breast development and irregular menstruation whereas none of the 46,XY subjects displayed pubertal changes. Eight different mutations were identified. Sixteen patients were either homozygotes or compound heterozygotes for the Q258X mutation. The seven other mutations identified were 189delG, 246insG, 564del13bp, 838delA, Q212X, A218V and M225T. The 189delG, 246insG, 546del13bp and Q212X mutants encode truncated proteins. COS-1 cells transfected with expression vectors encoding cDNAs for the mutant StAR proteins which affect the C-terminus, 838delA, A218V and Q258X, exhibited no steroidogenesis enhancing activity. However, the M225T mutant retained some steroidogenic activity. The patient with the M225T mutation had late onset of this disorder and some capacity to secrete testosterone in response to hCG. These findings suggest: (i) that the Q258X mutation can be used as a genetic marker for the screening of Japanese for lipoid CAH, (ii) that the C-terminus of StAR plays an important role in the protein's activity and (iii) that there are differences in the extent of functional impairment of the testis and ovaries in lipoid CAH.   相似文献   
32.
Intravenous injection of acetaldehyde produced hypotensive actions in pentobarbital-anaesthetised whole rats, but hypertensive actions in pithed rats. The hypotensive effects of acetaldehyde in whole rats were abolished by pre-treatment with yohimbine. In pithed rats, the hypertensive effects of acetaldehyde were significantly attenuated by prazosin and phentolamine, and in rats that had been pre-treated with reserpine. Our results suggest that the hypertensive actions of acetaldehyde in pithed rats are due to the release of catecholamines, which subsequently leads to vasoconstriction. In whole rats the hypotensive actions of acetaldehyde may be due to alpha2-adrenoceptor stimulation in the central nervous or peripheral system.  相似文献   
33.
To evaluate the effect of neoadjuvant chemotherapy on gastric cancer, we examined the correlation between induction of apoptosis and expression of p53, Bcl-2, and Bax. Eighty-five patients with advanced gastric cancer were retrospectively divided into the following two groups: 54 patients received 5-fluorouracil (5-FU) at 300 mg/body/day for 14 days and cisplatin (CDDP) at 15 mg/body/day for 2 days as group A; 31 patients without any preoperative chemotherapy as group B. According to histological changes in tumors due to neoadjuvant chemotherapy, the therapeutic effects on tumors were evaluated. The apoptotic index (AI) of group A was significantly higher than that of group B (1.12+/-0.40 vs. 0.67+/-0.24; p<0.01). In group A, the AI of p53-positive cases was significantly lower than that of negative cases (0.92+/-0.32 vs. 1.39+/-0.32; p<0.01). The AI of histological responders was significantly higher than that of non-responders (1.34+/-0.35 vs. 1.02+/-0.38; p<0.01). There was no significant correlation between AI and expression of Bcl-2 or Bax. In group A, histological responders, Bcl-2 positive, and high AI patients had better prognosis, respectively. In conclusion, neoadjuvant chemotherapy for gastric cancer enhanced induction of apoptosis, and AI might be useful to evaluate the effect of neoadjuvant chemotherapy.  相似文献   
34.
There are few reports on overall usefulness of adjuvant chemotherapy in gastric cancer patients. We tried to clarify, using multivariate analysis, usefulness of postoperative adjuvant oral chemotherapy in advanced gastric cancer patients after curative resection. Four hundred and eighty-two gastric cancer patients enrolled in a randomized controlled trial were classified into 2 groups based on postoperative chemotherapeutic regimen: oral doxifluridine (5'-DFUR, an intermediate metabolite of capecitabine) (n=245) or oral 5-fluorouracil (5-FU) (n=237). The significant prognostic factors in patients with serosal invasion were chemotherapeutics (5'-DFUR vs. 5-FU) (risk ratio 1.649; 95% CI, 1.112-2.437), lymph node metastasis (no vs. yes) (2.823; 1.422-5.604), and tumor differentiation (differentiated vs. undifferentiated) (1.727; 1.068-2.791). Significant factors influencing peritoneal recurrence time were chemotherapeutics (1.756; 1.063-2.902), serosal invasion (no vs. yes) (2.237; 1.264-3.961), lymph node metastasis (2.541; 1.267-5.095), tumor differentiation (2.656; 1.374-5.136), and tumor location (others vs. total) (3.595; 2.006-6.443). There were no differences in the overall survival between chemotherapy. However, 5'-DFUR produced a better survival time of patients with serosal invasion than 5-FU, that might be attributed to the prevention of peritoneal recurrence in this subset.  相似文献   
35.
Neurotrophins enhance the survival of cells in the nervous system under both physiological and pathological conditions, such as those caused by disease or trauma. We recently demonstrated that expression of brain-derived neurotrophic factor (BDNF) was up-regulated in neurons and glia after compression-induced spinal cord injury (SCI). We show here the effects of BDNF on the oligodendrocyte survival and functional recovery after SCI. The effects of intrathecally administered BDNF on both Cu/Zn superoxide dismutase (CuZnSOD) and myelin basic protein (MBP) expression were examined using rats that had received compression-induced spinal cord injury. CuZnSOD expression in the spinal cord was down-regulated within 24 h of compression-induced injury and then recovered. Continuous infusion of BDNF inhibited the acute down-regulation of CuZnSOD expression. In situ hybridization showed that CuZnSOD was expressed in both neurons and glia. Although MBP expression was greatly reduced after injury, BDNF administration promoted the recovery of MBP expression nearly to a control level after 2 wk. Furthermore, BDNF administration also prompted behavioral recovery. These results suggest BDNF's usefulness in human clinical applications. The attenuation of CuZnSOD down-regulation may be related to a protective effect of BDNF and the promotion of MBP up-regulation may be related to a long-lasting restorative effect.  相似文献   
36.
Naive Th cells obtained from OVA(323-339)-specific DO11.10 TCR-Tg mice did not express preproenkephalin (PPE) mRNA. However, culture of naive Th cells with OVA(323-339) peptide (OVA-pep) plus IL-2 under Th2-inducing conditions for 7 days resulted in an induction of PPE mRNA. The PPE mRNA was also induced by culturing with OVA-pep plus IL-2 (neutral condition). However, PPE mRNA induction under neutral conditions was totally abrogated by addition of anti-IL-4 mAb. The existence of methionine-enkephalin was also demonstrated in peptidase-digested peptides derived from Th2 cell lysate. These results demonstrate that IL-4 is a critical factor for the induction of PPE mRNA in freshly expanded antigen-specific Th2 cells.  相似文献   
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To clarify the correlation between the expression level of thymidine phosphorylase (TP) and efficacy of doxifluridine (5'-DFUR) and 5-fluorouracil (5-FU), samples from 177 colorectal cancer patients who underwent curative resection were evaluated by immunohistochemical staining using a newly developed monoclonal antibody 1C6-203. Patients were randomly given either oral 5'-DFUR or 5-FU as postoperative adjuvant chemotherapy. In Dukes' C staged colon cancer patients treated with 5'-DFUR, better survival was observed in the high TP patients than the low TP patients (P=0.025 by the log-rank test). The observed 5-year survival rates were 91.2 and 74.8%, respectively. No correlation between TP expression and patient prognosis was detected in the 5-FU group. In Dukes' C stage colon patients with high TP expression, the 5'-DFUR group had slightly better survival than the 5-FU group. These findings suggest that TP may be a chemosensitive marker for 5'-DFUR as postoperative adjuvant chemotherapy for advanced colon cancer patients.  相似文献   
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