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991.
Corn oil is well tolerated by mice but tolerance may decrease with excessive ingestion. In the present study, we compared the effects of optional ingestion of excessive corn oil with ingestion of water (control) or a 20% sucrose solution in mice. During the entire study, mice consistently ingested 100% corn oil and incrementally ingested 20% sucrose. Food intake in the corn-oil group was approximately constant but that in the sucrose group was slightly decreased. Body-weight gains in the corn-oil group were higher than those in the control and sucrose groups. At the end of the study, hepatic hypertrophy and fatty liver were present, especially in the corn-oil group, and the visceral fat of mice fed corn oil increased significantly compared with the other two groups. These results suggest that mice, when given a choice, will continue to overeat corn oil over the long term, inducing excessive caloric intake and obesity.  相似文献   
992.
Mice were injected with kainic acid (KA) at a convulsive dose, followed by homogenization of the hippocampus in the presence of different protease and phosphatase inhibitors, and subsequent preparation of nuclear and cytosolic fractions. An intraperitoneal injection of KA resulted in marked expression of particular Fos family members, including c-Fos, Fra-2, and Fos-B, but not Fra-1 proteins, in both fractions 2 to 18 h after administration. These fractions were individually incubated at 30 degrees C for 1 to 18 h for determination of in vitro degradation. Similarly rapid degradation was seen with c-Fos protein between nuclear fractions obtained 2 and 18 h after administration, while no significant degradation was found for c-Fos protein in cytosolic fractions obtained 2 h after administration during incubation. By contrast, in vitro incubation led to rapid degradation of c-Fos protein in cytosolic fractions obtained 18 h after administration. Degradation profiles were peculiar to each member protein in nuclear and cytosolic fractions obtained 2 and 18 h after administration. Dialysis prevented degradation of c-Fos protein in nuclear fractions without markedly affecting that in cytosolic fractions in a manner independent of the time after administration. The addition of inhibitors for phosphatases, but not for proteases, accelerated the degradation of c-Fos protein in nuclear fractions previously dialyzed. These results suggest that in vivo KA signals may modulate heterologous machineries responsible for breakdown of each Fos family member in a unique manner in nuclear fractions, rather than cytosolic fractions, of murine hippocampus.  相似文献   
993.
Our experimental study revealed that pasteurization was sufficient for killing all tumor cells in any massive bone and that the osteoinductivity and mechanical strength of pasteurized bone were about same as that of a fresh bone graft and better than boiled or autoclaved bone. We have performed reconstruction surgery using pasteurized autogenous bone graft since 1990. Resected bone was warmed for 30 minutes in a homeothermal heater set at 60 degrees C and then placed back to the original anatomic site. The graft was fixed with a plate or intramedullary nail with or without bone cement. Based on our experience in 31 patients, no local recurrence was seen in the grafts. Among 24 patients who can be adequately evaluated, incorporation of graft was complete in 17 cases and partial in 4 cases. In 18 of 21 patients, uptake of radionuclide in the grafted pasteurized bone was detected on bone scintigraphy approximately 6 months after surgery, and the uptake increased gradually, which suggested revascularization and remodeling of grafted bone.  相似文献   
994.
995.
We report herein a rare case of primary lung cancer that occurred concomitantly with the calcified ova of a parasite. A 58-year-old man was referred to our department after a pulmonary abnormal shadow had been seen on a chest X-ray done at mass screening. A transbronchial lung biopsy (TBLB) revealed the calcified ova of a parasite. Because the possibility of concomitant lung cancer could not be ruled out, a lung biopsy was taken via video-assisted thoracic surgery (VATS). The pathological diagnosis was squamous cell carcinoma, and a left upper lobectomy was serially performed through a posterolateral thoracotomy. The patient recovered uneventfully and has remained in good health without any sign of recurrence for over 9 months. Following this case report, we review three other cases of this unusual disease combination documented in the literature. Received: April 17, 2000 / Accepted: November 20, 2000  相似文献   
996.
BACKGROUND AND PURPOSE: Cerebral microcirculatory changes during cerebral vasospasm after aneurysmal subarachnoid hemorrhage (SAH) are still controversial and uncertain. The aim of this study was to investigate the changes of cerebral microcirculation during cerebral vasospasm and to clarify the roles of microcirculatory disturbances in cerebral ischemia by measuring cerebral circulation time (CCT) and regional cerebral blood flow (rCBF). METHODS: In 24 cases with aneurysmal SAH, rCBF studies by single-photon emission CT and digital subtraction angiography (DSA) were performed on the same day between 5 and 7 days after SAH and/or within 4 hours after the onset of delayed ischemic neurological deficits. CCT was obtained by analyzing the time-density curve of the contrast media on DSA images and was divided into proximal CCT, which was the circulation time through the extraparenchymal large arteries, and peripheral CCT, which was the circulation time through the intraparenchymal small vessels. They were analyzed in association with rCBF and angiographic vasospasm. RESULTS: Severe angiographic vasospasm statistically decreased rCBF, and correlation between the degree of angiographic vasospasm and rCBF was seen (r=0.429, P=0.0006). Peripheral CCT showed strong inverse correlation with rCBF (r=-0.767, P<0.0001). Even in none/mild or moderate angiographic vasospasm, prolonged peripheral CCT was clearly associated with decreased rCBF. CONCLUSIONS: In addition to the marked luminal narrowing of large arteries detected as severe angiographic vasospasm, microcirculatory changes detected as prolonged peripheral CCT affected cerebral ischemia during cerebral vasospasm. These results suggested that impaired autoregulatory vasodilation or decreased luminal caliber in intraparenchymal vessels may take part in cerebral ischemia during cerebral vasospasm.  相似文献   
997.
The authors reported a rare case of chronic subdural hematoma presenting bilateral visual impairment caused by papilledema. A 49-year-old man was admitted to our department due to left blurred vision. On admission, ophthalmological examination revealed visual acuity disturbance on the left eye, bilateral nasal visual field defect and papilledema. CT scan and MRI demonstrated bilateral subdural hematoma. No remarkable findings were detected on cerebral angiography. After evacuation of bilateral subdural hematomas, his visual symptoms recovered. In this report, we discuss the mechanism of visual impairment caused by chronic subdural hematoma.  相似文献   
998.
INTRODUCTION: We report the characteristics, diagnosis and treatment of dural arteriovenous fistula (DAVF) of the hypoglossal canal in nine patients with this relatively rare vascular disorder. METHODS: Of 248 patients with intracranial DAVFs managed at our institution, nine patients (3.6%; four men, five women; mean age 62 years) were diagnosed with hypoglossal canal DAVF. We investigated patient characteristics with respect to clinical symptoms, neuroradiological findings, efficacy and complications related to endovascular treatment. RESULTS: Seven patients had experienced head injury. All patients presented with pulsatile tinnitus. One patient displayed ipsilateral hypoglossal nerve palsy before treatment. MR angiography showed a "magic wand" appearance between the affected hypoglossal canal and the internal jugular vein in four patients. Angiography demonstrated an AV fistula on the medial aspect of the superior jugular bulb, mostly arising from the bilateral occipital, ascending pharyngeal and vertebral arteries with drainage to the internal jugular vein via the anterior condylar vein. Contralateral carotid injection accurately clarified the shunting point. Five patients underwent endovascular treatment: transarterial embolization (TAE; n = 2), transvenous embolization (TVE; n = 2), and TAE/TVE (n = 1). Complete shunt obliteration was achieved in four patients and shunt reduction in one. The remaining four patients were treated conservatively and the shunt had disappeared at follow-up. Postoperative hypoglossal nerve palsy occurred in one patient after TVE, possibly due to coil overpacking. CONCLUSION: The incidence of hypoglossal canal DAVF was not very low in our series. Contralateral carotid injection is an essential examination to provide an accurate diagnosis. TVE should be considered when access is available, although TAE is also appropriate for shunt reduction.  相似文献   
999.
In many patients without clinical metastases, cancer cells have already escaped from the primary tumor and entered a distant organ. A long-standing question in metastasis research is why some disseminated cancer cells fail to complete steps of metastatic colonization for extended periods of time. Our laboratory identified c-Jun NH(2)-terminal kinase activating kinase 1/mitogen-activated protein kinase kinase 4 (JNKK1/MKK4) as a metastasis suppressor protein in a mouse xenograft model of experimental i.p. ovarian cancer metastasis. In this model, expression of JNKK1/MKK4 via activation of p38 delays formation of >or=1-mm implants and prolongs animal survival. Here, we elucidate the time course of this delay as well as the biological mechanisms underpinning it. Using the Gompertz function to model the net accumulation of experimental omental metastases, we show that MKK4-expressing implants arise, on average, 30 days later than controls. Quantitative real-time PCR shows that MKK4 expression does not have a substantial effect on the number of cancer cells initially adhering to the omentum, and terminal deoxyribonucleotidyl transferase-mediated dUTP nick end labeling analysis shows that there is no increase in apoptosis in these cells. Instead, immunohistochemical quantitation of cell cycle proteins reveals that MKK4-expressing cells fail to proliferate once they reach the omentum and up-regulate p21, a cell cycle inhibitor. Consistent with the time course data, in vitro kinase assays and in vivo passaging of cell lines derived from macroscopic metastases show that the eventual outgrowth of MKK4-expressing cells is not due to a discrete selection event. Rather, the population of MKK4-expressing cells eventually uniformly adapts to the consequences of up-regulated MKK4 signaling.  相似文献   
1000.
The static stabilometry patterns associated with Parkinson's disease (PD, n = 15) and spinocerebellar ataxia (SCA, n = 15) were compared with those of normal control (n = 15) by measuring the fractal dimensions. Fractal dimensions were estimated using the modified pixel dilation (mPD) method. The fractal dimensions with closed eyes showed a significant correlation with Environmental area for SCA group (p < 0.05). The fractal dimension for SCA group was significantly higher with closed eyes than that with open eyes (p < 0.05). The fractal dimension with closed eyes was significantly higher in PD and SCA groups than that in normal group (p < 0.05). The fractal dimension with closed eyes was higher when the clinical stage was more severe with PD and SCA group while Environmental and Longitude/Environmental areas were not. These findings suggest that the fractal dimension is more sensitive than traditional stabilometric analysis in an evaluation of postural instability in PD and SCA.  相似文献   
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