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81.
This retrospective study clarified the success rate of endoscopic endodontic surgeries and identified predictors accounting for successful surgeries. In this retrospective study, 242 patients (90 males, 152 females) who underwent endoscopic endodontic surgery at a single general hospital and were diagnosed through follow-up one year later were included. Risk factors were categorized into attributes, general health, anatomy, and surgery. Then, the correlation coefficient was calculated for the success or failure of endodontic surgery for each variable, the odds ratio was calculated for the upper variable, and factors related to the surgical prognosis factor were identified. The success rate of endodontic surgery was 95.3%, showing that it was a highly predictable treatment. The top three correlation coefficients were post, age, and perilesional sclerotic signs. Among them, the presence of posts was the highest, compared with the odds ratio, which was 9.592. This retrospective study revealed the success rate and risk factors accounting for endoscopic endodontic surgeries. Among the selected clinical variables, the presence of posts was the most decisive risk factor determining the success of endodontic surgeries.  相似文献   
82.
To determine the utility of transrectal ultrasound (TRUS)-guided 10-core prostate biopsy (sextant plus 4 far lateral cores) for Japanese patients, we compared it with the standard sextant for detection of prostate cancer. The study patients were 564 consecutive Japanese men (median age 71 years) who underwent 10-core biopsy because of PSA values of > or = 2.0 ng/ml at Hiroshima University Hospital between March 2000 and December 2004. The overall cancer detection rate for the 10-core biopsy was 42.6% (240/564), which was significantly higher than the 36.3% (205/564) for the standard sextant biopsy (P=0.0330), with a 14.6% (35/240) improvement. The 10-core biopsy also detected a significant number of additional cancers in the sub-groups of patients with PSA values of 2 to approximately 10 ng/ml (P=0.0275), a prostate volume of > 20 cc (P=0.0440), or normal findings of digital rectal examination (P=0.0304). The 10-core biopsy scheme detected 9.6% and 2.1 to approximately 8.3% more cancers than the lateral sextant (apex, lateral mid portion, and lateral base) and the probable different combinations of 8-core biopsy designs, respectively. Compared to the standard sextant biopsy, the 10-core biopsy did not detect an increased proportion of clinically insignificant cancers. There was no severe morbidity, and only 2 patients (0.4%) were briefly hospitalized due to high fever. These results show that the TRUS-guided 10-core biopsy yields a better prostate cancer detection rate than the 6-core or 8-core protocol without severe complications. Therefore, it seems to be practicable for Japanese patients.  相似文献   
83.
Celiac axis stenosis is found at an incidence of 2%–24% in the general population. During pancreatoduodenectomy in patients with celiac axis stenosis, division of the gastroduodenal artery from the common hepatic artery may cause acute ischemia of the upper abdominal organs, such as the liver, stomach, or spleen. Under these circumstances, the clinical indications of arterial reconstruction remain controversial. Between 1994 and 2003, seven patients with celiac axis stenosis (n = 4) or occlusion (n = 3) underwent pancreatoduodenectomy at our hospital. Arterial reconstruction, including division of the median arcuate ligament, was conducted in two patients; the replaced right hepatic artery was preserved in one patient, and no vascular refinement was undertaken in the remaining four of the seven patients. In two of the four patients without arterial reconstruction or preservation, the serum levels of liver enzymes were markedly elevated (> 800 IU/l) on postoperative day 1, and these patients subsequently developed liver abscesses. Two patients who underwent arterial reconstruction and three patients who showed no decrease in intrahepatic arterial flow under Doppler ultrasonography after clamping of the gastroduodenal artery developed no ischemic complications. Although our experience is limited, when intraoperative Doppler ultrasonography indicates a decrease in the hepatic arterial signals, we believe that reconstruction of the hepatic artery will be necessary to minimize ischemic complications in the liver in patients with celiac axis stenosis.  相似文献   
84.
A 54-year-old man was admitted to our hospital due to intermittent chest pain. He had a history of acute myocardial infarction, and peri-stent contrast staining had been observed at the stent implantation site. The patient previously underwent anticoagulation therapy for left ventricular thrombus and antiplatelet therapy to prevent stent thrombosis. More than one year after implantation of a drug-eluting stent, antiplatelet drugs were discontinued, and anticoagulant alone was prescribed according to the guidelines, which resulted in very late stent thrombosis. The risks of both bleeding and thrombosis must be fully considered when deciding whether or not to discontinue antiplatelet therapy during anticoagulation therapy.  相似文献   
85.
86.
ObjectivesLaparoscopic abdominal surgery (LS) has been prevailing over open surgery (OS). However, its functional outcomes in the aging generation have not been sufficiently examined. We compared changes in physical status and earlier resumption of oral intake between LS and OS.MethodsUsing the Japanese administrative database, we matched variables affecting LS and compared them between LS and OS patients. During the 6-month period from July to December of 2006–2010, we examined the data from data from surviving patients of ≥15 year old who underwent isolated gastrectomy, colectomy, or anterior resection. Functional status was estimated by the Barthel index (BI) at admission and discharge. Outcomes were postoperative complications, BI deterioration, change in BI, and day of recommencing postoperative oral intake.ResultsWe identified 30,763 gastrectomies (laparoscopic: 7297), 31,958 colectomies (laparoscopic: 9364), and 12,545 anterior resections (laparoscopic: 4351). Variation in LS indications was observed in patient and hospital mixes. Among the paired-matched gastrectomy, colectomy, and anterior resection groups, LS was associated with fewer complications and earlier recovery of postoperative oral intake. Laparoscopic anterior resection (LAR) and colectomy were associated with less frequent BI deterioration. Longer operative time was associated with more complications, which then influenced BI deterioration in patients who underwent anterior resection.ConclusionsShorter operative time for LAR was associated with less functional deterioration than for laparoscopic gastrectomy and colectomy. Physicians should consider the appropriate indications for LS by concurrently avoiding unnecessary longer operations and their associated complications. More investment in teaching the skills necessary for LAR is recommended.  相似文献   
87.
Chromosomal and microsatellite instability in sporadic gastric cancer   总被引:5,自引:0,他引:5  
BACKGROUND: Gastric cancer can progress through two pathways of genomic instability: chromosomal (CIN) and microsatellite instability (MSI). It is hypothesized that these two pathways are not always independent and that some tumors show overlap between these two mechanisms. METHODS: A total of 98 sporadic gastric cancers were classified based on their MSI status, using microsatellite assay with BAT26. Evidence for CIN was investigated by identifying loss of heterozygosity (LOH) events on chromosome arms, 5q, 10p, 17p, 17q, and 18q, which are regions harboring tumor suppressor genes that are significant in gastric cancer development. RESULTS: Twelve tumors (12%) showed high-frequency MSI (MSI-H). Overall, 43 of the tumors (44%) had at least one LOH event, with most frequent chromosomal losses observed on 10p and 18q (30%, respectively), followed by 5q (21%), 17p (14%), and 17q (12%). Interestingly, overlap was observed between CIN and MSI pathways. Of 43 cancers with LOH events, four (9%) were also MSI-H. It was also found that 48% of cancers without MSI-H had no LOH events identified, comprising a subgroup of tumors that were not representative of either of these two pathways of genomic instability. CONCLUSION: These results suggest that molecular mechanisms of genomic instability are not necessarily independent and may not be fully defined by either the MSI or CIN pathways in sporadic gastric cancers.  相似文献   
88.
A 57-year-old man who had worked as a welder for about 40 years was admitted to our hospital. Every year he had had medical examinations in his workplace. On March 17, 1999, there was no finding of pneumoconiosis, but he had worked in a tunnel on a special arc welding project from December 20, 1999 to January 10, 2000. On admission, chest radiography revealed reticular shadows in the middle and lower lung fields. CT scans showed ground-glass opacities in both lungs. Serum iron was high (231 micrograms/dl) and serum ferritin was extremely high (2,309 ng/ml). Many iron particles were detected in the alveoli of the transbronchial biopsy specimen, and also in the sputum. A pathological diagnosis of siderosis was therefore made, and, considering the patient's occupation, the condition was termed arc welder's lung. This rapidly developing case was characterized by reticular shadows on chest radiography.  相似文献   
89.
We have previously demonstrated that stimulation of the angiotensin (Ang) II type 2 receptor in vascular smooth muscle cells caused bradykinin production by activating kininogenase in transgenic mice. The aim of this study was to determine whether overexpression of AT2 receptors in cardiomyocytes attenuates Ang II-induced cardiomyocyte hypertrophy or interstitial fibrosis through a kinin/nitric oxide (NO)-dependent mechanism in mice. Ang II (1.4 mg/kg per day) or vehicle was subcutaneously infused into transgenic mice and wild-type mice for 14 days. The amount of cardiac AT2 receptor relative to AT1 receptor in transgenic mice was 22% to 37%. Ang II caused similar elevations in systolic blood pressure (by approximately 45 mm Hg) in transgenic mice and wild-type mice. Myocyte hypertrophy assessed by an increase in myocyte cross-sectional area, left ventricular mass, and atrial natriuretic peptide mRNA levels were similar in transgenic and wild-type mice. Ang II induced prominent perivascular fibrosis of the intramuscular coronary arteries, the extent of which was significantly less in transgenic mice than in wild-type mice. Inhibition of perivascular fibrosis in transgenic mice was abolished by cotreatment with HOE140, a bradykinin B2 receptor antagonist, or L-NAME, an inhibitor of NO synthase. Cardiac kininogenase activity was markedly increased (approximately 2.6-fold, P<0.001) after Ang II infusion in transgenic mice but not in wild-type mice. Immunohistochemistry indicated that both bradykinin B2 receptors and endothelial NO synthase were expressed in the vascular endothelium, whereas only B2 receptors were present in fibroblasts. These results suggest that stimulation of AT2 receptors present in cardiomyocytes attenuates perivascular fibrosis by a kinin/NO-dependent mechanism. However, the effect on the development of cardiomyocyte hypertrophy was not detected in this experimental setting.  相似文献   
90.
To obtain insight into the role of the mitochondrial ATP-sensitive K(+) (mitoK(ATP)) channel in ischemic preconditioning (PC), we aimed to clarify the mitoK(ATP) channel-dependent phase of PC in two PC protocols with different intervals between PC ischemia and an index ischemia. The possible contribution of mitoK(ATP) channel opening to protein kinase C activation in PC was also examined by Western blotting. Myocardial infarction was induced by 30-min coronary occlusion/2-h reperfusion in rat hearts in situ, and infarct size was expressed as a percentage of the area at risk (% IS/AR). PC was performed with 2 episodes of 5-min ischemia, and each heart was subjected to 30-min ischemia either 5 min or 20 min after PC. At 5 min after PC, both PKC-delta and -epsilon were translocated and the myocardium was protected against infarction (% IS/AR = 28.3 +/- 2.7 % vs. 72.7 +/- 2.2 in controls p < 0.05). Pretreatment with a selective mitoK(ATP) channel blocker, 5-hydroxydecanoate (5-HD, 10 mg/kg), abolished the cardioprotection but not PKC translocation by PC. At 20 min after PC, PKC translocation remained at the same level as that 5 min after PC, but the anti-infarct tolerance was attenuated (%IS/AR = 43.5 +/- 4.7 %). Injection of 5-HD after PC did not affect anti-infarct tolerance at 5 min after PC but abolished the protection at 20 min after PC without any effects on PKC. These results suggest that the mitoK(ATP) channel plays a role in triggering of PC in a PKC-independent manner and that the role of the mitoK(ATP) channel as a mediator of protection is detectable after, but not before, the PC effect starts to decay without a change in the level of PKC translocation in the rat heart.  相似文献   
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