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81.
82.
The photocleavage reaction of dimer model compounds of photosensitive polyimides having cyclobutane rings in the main chain was studied. Efficient photocleavage was observed for the dimer models (CBAM2, CBAM4, and CBPM2) which had an electron-donating aromatic substituent at the electron-accepting imide group. On the other hand, the cleavage quantum yield was nearly zero for a dimer (CBCM2) which had a cyclohexane substituent instead of the aromatic ring. Solvent polarity effects on the cleavage quantum yield revealed that these dimers gave the largest photocleavage efficiency in medium-polar solvents. The transient absorption band of the excited triplet of CBPM2 was effectively quenched by oxygen, whereas no oxygen quenching was observed for the cleavage quantum yield. This leads to the conclusion that the cyclobutane ring in the polyimide is photocleaved via the excited singlet intramolecular CT state.  相似文献   
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Objective We recently reported a novel score for the detection of glomerular filtration rate (GFR) overestimation using a creatinine-based equation. We examined the utility of this score in patients with cardiovascular/renal diseases and diabetes mellitus. Methods We enrolled 1,425 patients (65±15 years old; 37% women) who were admitted to our hospital for the management of cardiovascular and renal diseases and their risk factors. Overestimation of the GFR (OE) was defined as a creatinine-based GFR (eGFRcre) ≥120% of the cystatin C-based estimated GFR. The OE score was calculated as the sum of the scores for the body weight, hemoglobin concentration, and blood urea nitrogen (BUN)/serum creatinine (Scr), totaling 1 point if the body weight was <63.0 kg in men or <42.0 kg in women, 1 point if the hemoglobin concentration was <12.4 g/dL in men or <11.0 g/dL in women, and 1 point if the BUN/Scr was >26.5. Results The proportion of patients with OE was 14.2%. The score predicted OE with a sensitivity of 70.8% and a specificity of 99.6%, and the sensitivity was increased in patients ≥75 years old (88.3%) and decreased in diabetics (58.6%). When patients were divided into subgroups by the total score, the frequencies of OE were 8% (59/754), 14% (72/502), 38% (58/151), and 72% (13/18) in patients with scores of 0, 1, 2, and 3, respectively. Conclusion The OE score is useful for detecting elderly cases of cardiovascular and renal diseases in which eGFRcre overestimates the GFR, although its utility is limited in diabetics.  相似文献   
85.
PurposeThis study investigated the use of psoas muscle area index (PAI) as an indicator of mortality risk in relation to survival in elderly patients after isolated surgical aortic valve replacement (SAVR) for aortic valve stenosis (AS).MethodsBetween January 2005 and March 2015, 140 patients with AS, aged ≥ 70 years, and with preoperative abdominal computed tomography scans, underwent elective, primary, isolated SAVR. PAI showed the ratio of the psoas muscle cross-sectional area at the fourth lumbar vertebral level to body surface area, and PAI less than the gender-specific lowest 20th percentile we called “low PAI” for the purposes of this study. Patients were classified as low PAI (n = 29) or normal PAI (n = 111).ResultsThe mean age in the low-PAI group was significantly older than in the normal-PAI group (81.0 vs. 77.3 years; p = 0.001). The mean follow-up was 4.25 years. The low-PAI group had a lower survival rate than the normal-PAI group at 1 year (89.7 ± 5.7% vs. 96.3 ± 1.8%), at 3 years (71.6 ± 9.3% vs. 91.5 ± 2.7%), and overall (53.0 ± 13.4% vs. 76.0 ± 5.6%; p = 0.039). The prognostic factors of mortality included low PAI (hazard ratio 2.95; 95% confidence interval 1.084–8.079; p = 0.034).ConclusionsPAI was associated with reduced overall survival after isolated SAVR in elderly people. PAI measurement may help to predict patient risks.  相似文献   
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A 25-year-old Japanese female was referred to our clinic for the investigation of moderate iron-deficiency anemia and epigastralgia. Endoscopic examination showed diffuse mucosal nodules in the gastric body resembling nodular gastritis, but this pattern was not observed in the antrum. Histology of the gastric biopsies taken from the gastric body showed mild atrophic mucosa with chronic active inflammation. Some of the biopsy specimens showed deposition of patchy, band-like subepithelial collagen. Four years later, the patient showed no clinical symptoms and signs. A follow-up endoscopic examination showed similar findings, which mimicked pseudopolyposis or a cobblestone-like appearance. The biopsy specimens from the depressed mucosa between the nodules revealed a thickened subepithelial collagen band with no improvement, which led to a diagnosis of collagenous gastritis. Treatment with oral administration of proton-pump inhibitors and histamine-2-receptor antagonists had proved ineffective. To make a correct diagnosis of collagenous gastritis, we should determine the characteristic endoscopic findings and take biopsies from the depressed mucosa between the nodules.  相似文献   
88.
We previously identified c-Jun NH2-terminal kinase (JNK)/stress-activated protein kinase-associated protein 1 (JSAP1, also known as JNK-interacting protein 3) as a scaffolding factor for JNK intracellular signaling pathways. Targeted gene-disruption studies have shown that JSAP1-null mice are unable to breathe and die shortly after birth. Although neural defects might be responsible for their death, there has been no convincing evidence for this. Here we first generated genetically engineered mice carrying a loxP-flanked (floxed) jsap1 gene. To evaluate the validity of this deletion as a jsap1 conditional knockout (KO), we created mice in which the same exon was deleted in all cell lineages, and compared their phenotypes with those of the jsap1 conventional KO mice reported previously. The two KO lines showed indistinguishable phenotypes, i.e., neonatal death and morphological defects in the telencephalon, indicating that the conditional deletion was a true null mutation. We then introduced the floxed jsap1 deletion mutant specifically into the neural lineage, and found that the jsap1 conditional KO mice showed essentially the same phenotypes as the JSAP1-null mice. These results strongly suggest that the neonatal death of jsap1-deficient mice is caused by defects in the nervous system.  相似文献   
89.
BACKGROUND/AIMS: Postoperative respiratory hypofunction sometime ruins quality of life of patients with esophageal cancer. From 1993, we introduced transhiatal esophagectomy without thoracotomy as a less invasive surgery to prevent postoperative respiratory complications for patients who have relatively early stage of esophageal cancer and have preoperative respiratory complication, or who are older in age. In this study, postoperative long-term evaluation of respiratory functions of patients with esophageal cancer who underwent esophagectomy was performed. METHODOLOGY: Among the patients with esophageal cancer who underwent esophagectomy in our hospital between 1993 and 1995, we selected 13 patients who underwent transhiatal esophagectomy (transhiatal group) and 9 patients who underwent transthoracic esophagectomy (transthoracic group). Conventional respiratory function tests (VC, vital capacity; FVC, forced vital capacity; FEV1, forced expiratory volume in 1 second; FEV1/FVC, ratio of FEV1 to FVC; PEF, peak expiratory flow) were compared between the two groups at 3, 6, and 12 months after operation. RESULTS: In the transhiatal group, postoperative average values of VC, FVC, and FEV1 recovered 92%, 98%, and 93% of preoperative average values at 6 months after operation, while in the transthoracic group, the average values of VC, FVC, and FEV1 were still 78%, 78%, and 72% of preoperative average values at 6 months after operation. Postoperative respiratory complications were detected in 4 patients (transhiatal: 2 and transthoracic: 2). The recovery rates of VC, FVC, FEV1, FEV1/FVC, and PEF at 6 months after operation of these 4 patients were not different from those of 18 patients without postoperative respiratory complications. CONCLUSIONS: In patients treated with transthoracic esophagectomy, postoperative respiratory hypofunctions continued over 6 months after surgery. However, postoperative respiratory complications may not be related with the long-term postoperative respiratory hypofunction in patients with esophageal cancer.  相似文献   
90.
OBJECTIVE: A newly designed combination chemotherapy for multiple myeloma, MMCP [ranimustine (MCNU), melphalan (MPH), cyclophosphamide (CPM) and prednisolone (PSL)], was analyzed and compared with the results of our previous randomized trial of VMCP [vincristine, MPH, CPM and PSL] and MMPP [MCNU, MPH, procarbazine and PSL]. METHODS: MCNU (33.3 mg/m2, div) on day 1 and MPH (4 mg/m2, po), CPM (66.7 mg/m2, po) and PSL (30 mg/m2, po) from day 1 to 4, were administered. Each cycle was repeated every 3 weeks. PATIENTS OR MATERIALS: From January 1991 until August 1995, 104 patients with multiple myeloma diagnosed at 10 hospitals of Nagoya Cooperative Study Group were enrolled. RESULTS: Of the 87 evaluable patients, partial response rate for MMCP was 65.5% and was significantly higher than that of VMCP (13/47=27.7%, p<0.0001) and that of MMPP (21/47=44.7%, p=0.0196). A plateau attainment was observed in 49.4%. The percentage of the patients who attained plateau was significantly increased in the MMCP arm than in the VMCP arm (19.1 %, p=0.0017) but was not in comparison with that of MMPP arm (42.6%, p=0.6790). Patients treated with MMCP survived significantly longer than those treated with VMCP or MMPP (p=0.0009 by generalized Wilcoxon test, p=0.0023 by log-rank test) with median survival for MMCP being 31.6 months, for VMCP 22.5 months, and for MMPP 22.9 months. No significant differences were observed with respect to adverse effects among the three regimens. CONCLUSION: The newly designed MMCP is a candidate as an induction chemotherapy for multiple myeloma.  相似文献   
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