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41.
Background Passive smoking has been reported to induce intervertebral disc degeneration in rats, and the objective of the present study was to histologically investigate changes in smoking-induced intervertebral disc degeneration after cessation of smoking. Methods Four-week-old rats were subjected to passive smoking for 8 weeks in a smoking box [20 cigarettes a day: one cigarette an hour (inhaled over 3 minutes and followed by ventilation with room air for 5 minutes)] to induce intervertebral disc degeneration. Smoke-free periods of different lengths were then established, and intervertebral discs were histologically analyzed. Results Immediately after 8 weeks of passive smoking, intervertebral discs exhibited cracks, tears, and misalignment of the annulus fibrosus, and increased fibrous tissue was seen in the nucleus pulposus. In addition, the level of interleukin-1β in intervertebral discs was higher in the smoking group than in the non-smoking group. After cessation, progression of degeneration ceased, and the matrix of the nucleus pulposus and annulus fibrosus exhibited increased fibrous connective tissue and proteoglycan. However, there were no changes in annulus fibrosus misalignment. Interleukin-1β levels also remained significantly elevated after 8 weeks of cessation. Conclusions While the annulus fibrosus degeneration caused by smoking was partially irreversible after cessation of smoking, the amount of mucin (proteoglycan) in the nucleus pulposus and annulus fibrosus tended to increase after cessation, thus suggesting the possibility that smoking-induced intervertebral disc degeneration can be repaired to some degree by cessation of smoking.  相似文献   
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43.
Background and aim  The endoscopic landmark of esophagogastric junction (EGJ) for diagnosis of Barrett’s esophagus (BE) differs between Japan and Western countries. Japanese endoscopists use the distal end of the lower esophageal palisade vessels to localize EGJ. In the West, endoscopists use the proximal gastric folds because of concerns that palisade vessels may be difficult to recognize. We evaluated whether there were differences between American and Japanese endoscopists in the recognition of palisade vessels. Method  A total of 82 patients were enrolled in this study. Patients were referred for diagnostic esophagogastroduodenoendoscopy (EGD) at the Veterans Affairs Palo Alto Health Care System, from May to July 2008. American and Japanese endoscopists evaluated the EGJ of patients undergoing diagnostic EGD. We analyzed the differences in the recognition of the distal end of palisade vessels. We calculated the kappa statistic to measure interobserver variability. Results  Based on localization using the distal end of the palisade vessels, American and Japanese endoscopists identified the EGJ in 87.8% (72/82) and 89.0% (73/82) of cases, respectively. The kappa statistic for visualization of EGJ was 0.88 [95% confidence interval (CI): 0.73–1.00]. Conclusion  American and Japanese endoscopists similarly recognized the distal end of palisade vessels as EGJ.  相似文献   
44.
We have previously reported that overexpression of wild-type amyloid precursor protein (APP) in postmitotic neurons induces cleavage-dependent activation of caspase-3 both in vivo and in vitro. In this study, we investigated the mechanism underlying APP-induced caspase-3 activation using adenovirus-mediated gene transfer into postmitotic neurons derived from human embryonal carcinoma NT2 cells. Overexpression of wild-type APP significantly increased intracellular (45)Ca(2+) content prior to the activation of caspase-3 in NT2-derived neurons. Chelation of intracellular Ca(2+) markedly suppressed APP-induced activation of caspase-3. Furthermore, calpain, a Ca(2+)-dependent cysteine protease, was activated in neurons overexpressing APP as assessed by increased levels of calpain-cleaved alpha-fodrin and autolytic mu-calpain fragments. Neither calpain nor caspase-3 was activated in neurons expressing an APP mutant defective in the Abeta(1-20) domain. Calpain inhibitors almost completely suppressed APP-induced activation of neuronal caspase-3. E64d, a membrane permeable inhibitor of calpain, significantly suppressed APP-induced neuronal death. These results suggest that overexpression of wild-type APP activates calpain that mediates caspase-3 activation in postmitotic neurons.  相似文献   
45.
It has been estimated that genetic factors or a combination of genetic and environmental factors play a role in the development of 10-15% of all cancers. A genetic cause of hereditary cancer has been identified in more than 40 diseases till now. For preventing this cancer, gene testing is essential because it has no definite clinical marker as in hereditary non-polyposis colorectal cancer: HNPCC. Much more experience must be accumulated in this testing at the clinical base in order to increase specificity and sensitivity while safeguarding ethical, legal and social issues (ELSI). Recently, the Personal Information Protection Law was enforced. Gene inspection involving hereditary cancer should be carried out under a comprehensive gene medical examination organization. It is important for the family doctor, medical specialist, and gene inspection person in charge to cooperate closely with one another, and this will be a subject of future study.  相似文献   
46.
OBJECTIVES: Insulin resistance is associated with chronic renal failure, which may amplify its cardiovascular pathologic manifestations. We previously showed the presence of insulin resistance in mild renal insufficiency due to chronic glomerulonephritis. These observations may be explained by a decrease in insulin sensitivity due to renal dysfunction. The aim of the present study was to evaluate the effects of unilateral and subtotal nephrectomy on insulin sensitivity. METHODS: Unilateral heminephrectomy and five-sixths nephrectomy (5/6Nx) were performed in male Sprague-Dawley rats, measuring steady-state plasma glucose (SSPG) during the insulin suppression test. RESULTS: The glomerular filtration rate (GFR) decreased significantly from sham-operated rats, to unilateral heminephrectomy group, to 5/6Nx rats. SSPG was unexpectedly lower in the unilateral heminephrectomy group than in controls, suggesting that unilateral heminephrectomy increased the sensitivity to insulin despite a mild decrease in renal function. However, when the analysis was limited to the 5/6Nx group, SSPG was inversely correlated with GFR (r = -0.65, p < 0.05). When renal failure caused by 5/6Nx had reached end stage, the rats became insulin resistant, despite a profound reduction in renal mass. CONCLUSION: It is suggested that unilateral heminephrectomy reduced GFR and increased the sensitivity to insulin. When rats became uremic, insulin sensitivity decreased, even, in 5/6Nx.  相似文献   
47.
A 57-year-old female with relapsing polychondritis (RP) showing CNS complications is described with reference to the MRI and SPECT findings. At the age of 56, the patient was diagnosed with RP based on her symptoms, which included bilateral auricular chondritis, nonerosive seronegative inflammatory polyarthritis, and ocular inflammation, as well as vestibular dysfunction. During the course of the disease, she suffered from aseptic meningitis accompanied by delirium, which was resolved by treatment with cyclophosphamide, in addition to prednisolone concurrent with the improvement of her physical condition. After the meningitis improved, she developed a number of cognitive impairments, including time disorientation, agraphia, acalculia, constitutional apraxia, and personality changes. Simultaneously, we observed, via SPECT, a decrease in cerebral blood flow (CBF) in several regions, including the bilateral frontal, lateral temporal, and parietal regions. This is the first study to report on the CNS manifestations of RP with reference to MRI and SPECT findings.  相似文献   
48.
OBJECTIVE: To report a case of premature ovarian failure (POF) and a mutation of the gene for Noggin (NOG). DESIGN: Case report. SETTING: University hospital. PATIENT(S): A 33-year-old Japanese female with POF and proximal symphalangism. INTERVENTION(S): Direct sequence analysis of the NOG gene. MAIN OUTCOME MEASURE(S): Occurrence of POF. RESULT(S): A novel heterozygous G to A transition was identified at the nucleotide position 142 (142 G>A), which is predicted to cause an amino acid substitution of glutamic acid by lysine (E48K). CONCLUSION(S): Because NOG is expressed in the ovary and interacts with bone morphogenetic proteins, which play an important role in the ovarian function, a NOG mutation may constitute one of the multiple susceptibility genes for the development of POF.  相似文献   
49.
A 64-year-old man with a 9.0 cm benign hepatic cyst near the hepatic hilum presented with obstructive jaundice caused by the compression of the hepatic ducts. The cyst was aspirated percutaneously, and minocycline hydrochloride was instilled as a sclerosant through a catheter inserted into the cyst. The cyst gradually became smaller, relieving the obstructive jaundice. There were no complications or side-effects. The instillation of minocycline hydrochloride is a useful alternative to ethanol instillation for treating benign hepatic cysts, even when the cyst is causing obstructive jaundice.  相似文献   
50.
We report a case of 9p-syndrome with congenital median nasal fistula in a boy born to a 28-year-old mother as the second child by normal delivery. The fistula opened at the base of the bridge of the nose and ran between the nasal septum cartilage to the anterior cranial fossa. A frontal craniotomy and transcolumellar skin incision were conducted to extirpate the fistula. In the 10 months since, no fistula has recurred.  相似文献   
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