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61.
The authors present a case of germinoma that was initially found in the pineal region and recurred 15 years later in the intramedullary cervical spinal cord after intensive chemo- and radiotherapy and diagnosis of complete remission. This 28-year-old man initially presented with seizures. Hydrocephalus and a pineal tumor were found on radiological examination, and partial resection of the tumor was performed. Histological diagnosis showed a pure germinoma. Following surgery, the patient received a combination of chemo- and radiotherapy, and a complete remission was shown. However, after 15 years of follow-up, he presented with gait disturbances. Spinal MRI showed an intramedullary mass lesion in the cervical spinal cord. The cervical lesion was biopsied, and histological examination again revealed a pure germinoma. With germinomas, the possibility of a drop metastasis from an intracranial lesion to the spinal cord must be considered during follow-up. However, in the present case, analysis of a CSF sample showed no abnormalities as in previously published cases. In recent years, multidisciplinary treatments have demonstrated good event-free survival rates in cases of pure germinomas, but long-term outcomes over the decades are not fully known. Continual follow-up of such cases is recommended even after complete remission has been achieved.  相似文献   
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Red-crowned cranes (Grus japonensis) are native to eastern Hokkaido (island population), in contrast to the mainland, which migrates between the Amur River basin and eastern China-Korea peninsula. During the 1990s we found that Red-crowned cranes in Hokkaido were highly contaminated with mercury: however, the source was unknown. We investigated the time trend of mercury contamination in Red-crowned cranes. Total mercury levels in the livers and kidneys from cranes dead in the 2000s were lower than those dead in the 1990s. Feather is a major pathway of mercury excretion for many bird species and is used as an indicator of blood mercury level during feather growth. As internal organs from the specimens collected before 1988 were not available, we analyzed the flight feather shavings from stuffed Red-crowned cranes dead in 1959-1987 and found that the mercury level of feathers from cranes dead in the 1960s and 1970s was not more than those from the cranes dead in the 2000s. These results suggest that mercury contamination in Red-crowned cranes in Hokkaido decreased temporally during the 1990s-2000s. This indicates the possible occurrence of some mercury pollution in Red-crowned cranes' habitat in this region in the 1990s or before.  相似文献   
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The purpose of this study was to evaluate the effect of direct hemoperfusion using a Polymyxin B (PMX) immobilized fiber column in septic patients with chronic renal failure after emergency surgery. Twenty-four renal failure patients, including 19 dialysis patients, with sepsis or septic shock were treated with direct hemoperfusion after emergency surgery. The 24 consecutive patients included nine with necrotic enterocolitis, six with colonic perforation due to diverticulitis, three with ruptured suture after colectomy, one with duodenal perforation, four with blood access infection, and one with an infected abdominal aortic aneurysm. The acute physiology and chronic health evaluation II score ranged from 13 to 26 (19 +/- 3). After completion of the first and the second hemoperfusion, mean blood pressure was significantly elevated from 69 +/- 12 mm Hg to 89 +/- 15 mm Hg and from 78 +/- 14 mm Hg to 95 +/- 13 mm Hg, respectively (P < 0.01). In addition, the catecholamine dosage needed to maintain the circulation could be decreased markedly after the treatment. The blood concentration of endotoxin in patients with Gram-negative sepsis, before and after the treatment, significantly decreased from 36 +/- 19 pg/mL to 19 +/- 19 pg/mL (P < 0.05). PMX was effective in patients with Gram-positive sepsis as well as Gram-negative sepsis. The 28-day mortality rate in patients who had emergency abdominal surgery was 10% (2/20), whereas that in patients with dialysis access infection was 50% (2/4). There was a significant difference in the Sequential Organ Failure Assessment (SOFA) score of all patients before and after treatment using PMX (9.2 +/- 3.3 vs. 7.5 +/- 3.5, P < 0.05). Furthermore, the SOFA score of survivors decreased significantly after PMX treatment (8.4 +/- 3.5 vs. 6.7 +/- 2.6, P < 0.01). Our results suggest that the early application of PMX may prevent multiple organ failure and improve survival in patients with chronic renal failure and sepsis/septic shock after emergency abdominal surgery, regardless of the type of pathogenic bacteria involved.  相似文献   
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The effects of the tetrodotoxin-insensitive Na+ channel activator palytoxin on both the secretion of endogenous catecholamines and the formation of 14C-catecholamines from [14C]tyrosine were examined using cultured bovine adrenal chromaffin cells. Palytoxin was shown to cause the stimulation of catecholamine secretion in a concentration-dependent manner. However, this toxin caused the reduction rather than the stimulation of 14C-catecholamine formation at the same concentrations. Palytoxin failed to cause any alteration in the activity of tyrosine hydroxylase prepared from bovine adrenal medulla. Furthermore, the uptake of [14C]tyrosine into the cells was shown to be inhibited by this toxin under the conditions in which the suppression of 14C-catecholamine formation was observed, and this inhibitory action on tyrosine uptake was closely correlated with that on catecholamine formation. The inhibitory action of palytoxin on tyrosine uptake into the cells was observed to be noncompetitive, and this effect was not altered by the removal of Na+ from the incubation mixture. These results suggest that palytoxin may be able to inhibit the uptake of [14C]tyrosine into the cells, resulting in the suppression of 14C-catecholamine formation, probably through its direct action on the plasma membranes of bovine adrenal chromaffin cells.  相似文献   
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Abstract:  Renal allograft specimens often show patchy tubular injury (PTI), or patches of injured tubular sections. PTI reflects damage to the proximal tubules, and the histologic findings consist of tubular cell necrosis and tubular regeneration without tubulitis. Unlike acute tubular necrosis (ATN) in cadaveric donors, PTI can be observed in kidneys from living donors when there is no history of acute renal failure after transplantation. In this study, we examined the clinicopathological importance of PTI in acute rejection. Between April 2000 and May 2007, 2252 biopsies of living kidney grafts were performed at least one d after the transplant operation. Acute rejection was observed in 877 biopsies. Of these cases, 78 (8.9%) biopsies from 43 patients showed PTI. The severity of the PTI was graded semiquantitatively as follows: grade 1 cases had three or four damaged tubular sections, grade 2 cases had >5 sections, and grade 3 cases had >10 sections. The incidence of PTI was significantly higher in vascular rejection (VR) and antibody-mediated rejection (AMR) patients than in those experiencing tubulointerstitial rejection (TIR). The mean PTI score was significantly higher (2.00 ± 0.12) in VR than in TIR (1.39 ± 0.10) and AMR (1.68 ± 0.08) patients. The mean serum creatinine (sCr) at the time of biopsy was higher in VR patients than in AMR and TIR patients. Moreover, in VR patients, those with severer PTI developed higher sCr levels. These data suggest that PTI has a strong relationship with local ischemic damage delegated by VR, and the severity of PTI could be a practical histological marker in acute vascular rejection.  相似文献   
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