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111.
Temporomandibular joint (TMJ) ankylosis is a pathological process caused by damage of the mandibular condyle. When this event takes place in subjects during the developmental age, it results in an alteration of the entire maxillofacial complex. Therefore, surgical methods able to remove the temporomandibular ankylosis also include necessary operations to correct the secondary maxillofacial deformity. The distraction osteogenesis has induced our center to modify the surgical protocol for the therapy of patients who have developed TMJ ankylosis and secondary maxillomandibular deformity. We have treated four patients with monolateral ankylosis of the TMJ and serious deformities of the maxillomandibular complex secondary to functional limitation. During the same operation, arthroplasty was performed with the removal of the ankylotic block and the interposition of a temporal muscle flap in the new articular space; an intraoral osteodistractor was also positioned to lengthen the mandible. All patients showed recovery of the eurhythmy of the face and good re-establishment of the symmetry. An average 12-month follow-up showed the average opening of the mouth to be at least 35 mm. The combination of TMJ arthroplasty and intraoral osteodistraction provides good functional and aesthetic results in patients affected by ankylosis who have developed secondary maxillofacial deformities.  相似文献   
112.
Primary surgery for cleft lip, alveolus, and palate is only the beginning of management for this condition, because the congenital malformation and the scars of corrective surgery during infancy affect the physiological development of the skeleton and the soft tissue. Once the patient has stopped growing, therefore, secondary maxillomandibular malformation is frequent in these patients. The most frequent skeletal malformations in secondary cleft lip and palate are hypoplasia and malposition in the three planes of the superior maxilla space. In these cases, combined orthodontic and surgical treatment is necessary; of the various techniques available, Le Fort I osteotomy is the one most indicated for repositioning of the maxilla. Although this technique is now standardized to correct the simple maxillo-mandibular malformation, in the case of secondary malformation in the cleft lip and palate, modifications are necessary in the surgical technique to ensure the best esthetic and functional result and to reduce the possibility of relapse. After 20 years' experience in the treatment of secondary skeletal malformation in cleft lip, alveolus, and palate, a critical review is made of the different steps of planning and performing Le Fort I osteotomy in these patients.  相似文献   
113.
Research on the cortical sources of nociceptive laser-evoked brain potentials (LEPs) began almost two decades ago (Tarkka and Treede, 1993). Whereas there is a large consensus on the sources of the late part of the LEP waveform (N2 and P2 waves), the relative contribution of the primary somatosensory cortex (S1) to the early part of the LEP waveform (N1 wave) is still debated.To address this issue we recorded LEPs elicited by the stimulation of four limbs in a large population (n = 35). Early LEP generators were estimated both at single-subject and group level, using three different approaches: distributed source analysis, dipolar source modeling, and probabilistic independent component analysis (ICA).We show that the scalp distribution of the earliest LEP response to hand stimulation was maximal over the central-parietal electrodes contralateral to the stimulated side, while that of the earliest LEP response to foot stimulation was maximal over the central-parietal midline electrodes. Crucially, all three approaches indicated hand and foot S1 areas as generators of the earliest LEP response.Altogether, these findings indicate that the earliest part of the scalp response elicited by a selective nociceptive stimulus is largely explained by activity in the contralateral S1, with negligible contribution from the secondary somatosensory cortex (S2).  相似文献   
114.
The main objectives of our study were to determine the bioavailability of omega-3 (ω-3) to the tumor, to understand its mechanisms, and to determine the feasibility of targeting the ω-6 polyunsaturated fatty acids (PUFAs) metabolizing 15-lipoxygenase-1 (15-LO-1) and cyclooxygenase-2 (COX-2) pathways. Nude mice injected subcutaneously with LAPC-4 prostate cancer cells were randomly divided into three different isocaloric (and same percent [%] of total fat) diet groups: high ω-6 linoleic acid (LA), high ω-3 stearidonic acid (SDA) PUFAs, and normal (control) diets. Tumor growth and apoptosis were examined as end points after administration of short-term (5 weeks) ω-3 and ω-6 fatty acid diets. Tumor tissue membranes were examined for growth, lipids, enzyme activities, apoptosis, and proliferation. Tumors from the LA diet-fed mice exhibited the most rapid growth compared with tumors from the control and SDA diet-fed mice. Moreover, a diet switch from LA to SDA caused a dramatic decrease in the growth of tumors in 5 weeks, whereas tumors grew more aggressively when mice were switched from an SDA to an LA diet. Evaluating tumor proliferation (Ki-67) and apoptosis (caspase-3) in mice fed the LA and SDA diets suggested increased percentage proliferation index from the ω-6 diet-fed mice compared with the tumors from the ω-3 SDA-fed mice. Further, increased apoptosis was observed in tumors from ω-3 SDA diet-fed mice versus tumors from ω-6 diet-fed mice. Levels of membrane phospholipids of red blood cells reflected dietary changes and correlated with the levels observed in tumors. Linoleic or arachidonic acid and metabolites (eicosanoid/prostaglandins) were analyzed for 15-LO-1 and COX-2 activities by high-performance liquid chromatography. We also examined the percent unsaturated or saturated fatty acids in the total phospholipids, PUFA ω-6/ω-3 ratios, and other major enzymes (elongase, Delta [Δ]-5-desaturase, and Δ-6-desaturase) of ω-6 catabolic pathways from the tumors. We observed a 2.7-fold increase in the ω-6/ω-3 ratio in tumors from LA diet-fed mice and a 4.2-fold decrease in the ratio in tumors from the SDA diet-fed mice. There was an increased Δ-6-desaturase and Δ-9 desaturase enzyme activities and reduced estimated Δ-5-desaturase activity in tumors from mice fed the SDA diet. Opposite effects were observed in tumors from mice fed the LA diet. Together, these observations provide mechanistic roles of ω-3 fatty acids in slowing prostate cancer growth by altering ω-6/ω-3 ratios through diet and by promoting apoptosis and inhibiting proliferation in tumors by directly competing with ω-6 fatty acids for 15-LO-1 and COX-2 activities.  相似文献   
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116.
INTRODUCTION: Primary neurogenic tumours of facial nerve are uncommon with the majority found intra-temporally. Intracranial and intra-parotid neoplastic involvement of cranial nerve VII is much less common. There are 11 reported cases, in the English-language literature, of intra-parotid facial nerve plexiform neurofibromas with eight of them associated with NF1. MATERIALS AND METHODS: A child, 10 years old, with NF1, reached us for a cheek swelling, slowly increased in previous 8 years. At the age of 3 years, a plexiform neurofibroma was diagnosed by biopsy of the lesion. Clinical examination and NMR showed in the sub-cutaneous tissue of the right cheek, two contiguous nodular lesions, about 2 cm x 1.5 cm in diameter; a third neoformed lesion, about 1cm in diameter, was located above the ipsilateral labial commissure. No facial nerve impairment was seen. The patient underwent superficial parotidectomy with removal of the lesions and preservation of the facial nerve. RESULTS: The patient had a considerable regional swelling in the immediate post-operative course; no facial nerve impairment was observed. The swelling of the cheek did not show a fully regression in the post-operative course. Ultrasonography at 3 months showed a recurrence of disease. DISCUSSION: Plexiform neurofibromas should be distinguished due to their risk of malignant transformation seen in up to 15% of patients affected by NF1. Surgery is the only effective option currently available for the treatment of PNF. However, success of surgical intervention is limited by the infiltrating nature of the tumours, resulting in a high rate of tumour re-growth. Facial nerve preservation during surgery is unlikely and significant morbidity can result from their excision. The age of the patient at surgical resection seemed to influence outcome: tumours resected before age 10 years recurred in 60% of cases compared with only 30% recurrence in patients older than the age of 10 years. CONCLUSION: Indication and timing of surgery, in paediatrics patients with NF1, are complex. To avoid eventual physical and psychological consequences, it seems prudent to delay surgery as long as it is feasible for otherwise asymptomatic paediatric patients with facial plexiform neurofibroma.  相似文献   
117.
血小板活化因子受体的研究进展   总被引:9,自引:1,他引:8  
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Intraoperative ultrasound (US) was compared to computed tomography (CT) in 41 intracranial and 6 spinal cord tumors. The studies correlated closely except for primary gliomas. Eight of the 22 primary intracranial gliomas (37%), including 1 low-grade and 7 anaplastic tumors, were larger and more extensive on US than on CT. Margins of non-enhanced primary astrocytomas were shown by US but not CT. Four anaplastic tumors (19%) exhibited echogenicity extending beyond the enhanced area. In 4 patients an enhanced lesion contained a lucent center which proved to be echogenic. Low-grade astrocytomas were relatively homogeneous on US, while anaplastic astrocytomas were more inhomogeneous. Cysts could be found in both types of astrocytomas and were often small and multiple. The echo pattern was not helpful in differentiating metastases from primary tumors, although all of them had sharp margins. Sonography of the central nervous system can provide valuable information about tumor morphology and margins.  相似文献   
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