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The purpose of this study was to review clinical and radiographic outcomes of perilunate dislocations and fracture dislocations treated with external fixation and K-wire fixation. Twenty patients (18 males and two females) with a mean age of 38 years (range 18–59) who had an acute dorsal perilunate dislocation or fracture dislocation were treated with the use of wrist external fixator and K-wires. The injuries included 12 perilunate dislocations, seven trans-scaphoid perilunate fracture dislocations, and one trans-styloid perilunate fracture dislocation. The median time from trauma to operation was 8 h (2–12 h). Indirect reduction via ligamentotaxis was achieved in all perilunate dislocation, and provisional K-wire fixation was added. In five of seven trans-scaphoid perilunate fracture dislocations, indirect reduction was achieved; whereas in the other two as well as in the case of trans-styloid perilunate fracture dislocation, open reduction was required. External fixator was supplemented with K-wires for stabilization of the fractures and the intercarpal intervals. The interosseous and capsular ligaments were not repaired, even after open reduction of fracture dislocations. The mean follow-up was 39 months (range 18–68 months). Range of motion and grip strength were measured. Cooney’s scoring system was used for the assessment of clinical function. Radiographic evaluation included time to scaphoid union, measurement of radiographic parameters (scapholunate gap, scapholunate angle, lunotriquetral gap, and carpal height ratio) and any development of arthritis. The flexion-extension motion arc and grip strength of the injured wrist averaged 80 and 88%, respectively, of the corresponding values for the contralateral wrists. According to Cooney’s clinical scoring system, overall functional outcomes were rated as excellent in four patients, good in eight, fair in six, and poor in two. Eighteen patients returned to their former occupations. Two patients with a trans-scaphoid perilunate injury developed nonunion of the scaphoid; one of them required scaphoid excision and midcarpal fusion. Two patients had radiographic evidence of arthritis. The use of external fixation and provisional K-wire fixation for the treatment of acute perilunate dislocations is associated with satisfactory midterm functional and radiographic outcomes. This minimally invasive treatment option is simple, reliable, and minimally invasive method that provides proper restoration and stable fixation of carpal alignment.  相似文献   
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Blink reflex (BR) was studied in 17 patients with histochemically and genetically confirmed mitochondrial myopathy (MM). Fourteen patients had chronic progressive external ophthalmoplegia (CPEO) associated with a mild to moderate craniosomatic myopathy without any symptoms or signs of central nervous system (CNS) involvement, 2 myoclonic epilepsy with ragged red fibers syndrome, and 1 Kearns-Sayre syndrome. The mean latencies of the early (R1) and late (R2) responses were prolonged (P < 0.01 and P < 0.001, respectively), and the corresponding amplitudes decreased (P < 0.001). Increased habituation of the reflex was clearly observed in 10 out of 14 patients tested (71.4%), 9 of whom presented CPEO. These findings suggest that the brain stem reticular network is in a state of basal inhibition which is presumably due to a subclinical impairment of the cerebral cellular metabolism. Multimodal evoked potentials revealed abnormalities suggestive of CNS involvement in 7 out of 17 patients (41.2%), 4 of whom had CPEO. These observations document the validity of BR in detecting clinically silent brain stem impairment in patients with apparently pure MM and provide important clues for a further understanding of the underlying pathophysiology. © 1996 John Wiley & Sons, Inc.  相似文献   
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We evaluated the safety and efficacy of image-guided radiofrequency ablation (RFA) using a triple-spiral-shaped electrode needle for unresectable primary or metastatic hepatic tumors. Thirty-four patients with 46 index tumors were treated. Ablation zone, morbidity, and complications were assessed. The lesions were completely ablated with an ablative margin of about 1 cm. Five patients (14.7%) with a lesion larger than 4.5 cm had local tumor progression after 1 month and were retreated. Hemothorax, as a major complication, occurred in 1 of 34 patients (3.0%) or 1 of 46 lesions ablated (2.2%). RFA using this new electrode needle can be effective in the treatment of large unresectable hepatic tumors.  相似文献   
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BACKGROUND AND OBJECTIVES: Serum beta(2)-microglobulin (s beta(2)m) is an established prognostic factor for multiple myeloma and non-Hodgkin's lymphoma, but only limited data suggest an adverse prognostic significance for Hodgkin's lymphoma (HL). This study was undertaken to examine the impact of s beta(2)m on the prognosis of patients with HL. DESIGN AND METHODS: s beta(2)m was measured by a radioimmunoassay (upper normal limit 2.4 mg/L), in pretreatment serum samples of 232 patients with HL, who were then treated with ABVD or equivalent regimens with or without radiotherapy. Multivariate survival analysis was based on Cox's proportional hazards model. RESULTS: Main patients' characteristics: median age 30.5 years (14-78); 58% males; 68% nodular sclerosis, 20% mixed cellularity and 12% lymphocyte predominance; 34% B-symptoms; 24% Ann Arbor stage I, 49% II, 18% III and 9% IV. Elevated s beta(2)m levels were detected in 65/232 patients (28%) and correlated with older age (p<0.001), mixed cellularity (p=0.03), B-symptoms (p=0.002), advanced stage (p=0.02), > or = 5 involved sites (p=0.02), inguinal/iliac involvement (p=0.009), lymphocytopenia (p=0.002) and elevated lactate dehydrogenase (p=0.01). The 7-year failure free survival (FFS) was 75% vs. 72% for patients with normal vs. elevated s beta(2)m (p=0.15). The corresponding 7-year overall survival (OS) rates were 86% vs. 52% (p=0.003). In multivariate analysis, elevated s beta(2)m was not predictive of FFS, but was independently associated with inferior OS (p=0.01), along with the number of involved sites (p<0.001). INTERPRETATION AND CONCLUSIONS: s beta(2)m is not a potent prognostic factor for FFS in optimally treated patients with HL. However s beta(2)m may be predictive of OS, probably due to its effect on the timing of treatment failure.  相似文献   
27.
Pheochromocytoma cell lines derived from neurofibromatosis knockout mice express high levels of the receptor tyrosine kinase Ret, which is involved in the pathogenesis of human pheochromocytomas in hereditary multiple endocrine neoplasia syndrome type 2 (MEN2). Mouse pheochromocytoma (MPC) cells respond to the Ret-activating ligand GDNF by exhibiting Ret phosphorylation, neurite outgrowth, decreased proliferation, and altered expression of catecholamine biosynthetic enzymes. GDNF exerts similar effects on human pheochromocytoma cells in primary cultures. Ret is minimally expressed by normal mouse chromaffin cells, from which pheochromocytomas are derived. Its expression at high levels by MPC cells suggests possible relationships between two previously unrelated tumor syndromes, neurofibromatosis, and MEN2. The responsiveness of these cells to GDNF suggests that they may be a valuable new model for neurobiology.  相似文献   
28.
Fibrosarcoma of bone is a relatively rare tumor; it accounts for less than 5% of bone sarcomas. The anatomical sites most commonly involved are the metaphyses of long tubular bones. Local pain, swelling, limitation of motion, and pathologic fracture are the common clinical signs and symptoms. Typical imaging findings include eccentrically located lytic lesions, with a geographic, moth-eaten, or permeative pattern of bone destruction, and extension into adjacent soft tissues. Surgery is the treatment of choice. The type of surgical procedure depends mainly on histologic grade, local conditions, and tumor location. With a high probability of metastases (>70%) after surgical treatment, perioperative adjuvant treatment modalities should be considered for high-grade tumors. The most important prognostic factors affecting survival include tumor grade, patient's age, and tumor location.  相似文献   
29.
Purpose. This review highlights the state-of-the-art in pharmaceutical microemulsions with emphasis on self-emulsifying systems, from both a physical and biopharmaceutical perspective. Although these systems have several pharmaceutical applications, this review is primarily focused on their potential for oral drug delivery and intestinal absorption improvement. Methods. Physicochemical characteristics and formulation design based on drug solubility and membrane permeability are discussed. Results. Case studies in which lipid microemulsions have successfully been used to improve drug solubilization/dissolution and/or intestinal absorption of poorly absorbed drugs/peptides are presented. Conclusions. Drug development issues such as commercial viability, mechanisms involved, range of applicability, safety, scale-up and manufacture are outlined, and future research and development efforts to address these issues are discussed.  相似文献   
30.

Background  

Neuroblastoma is a solid tumour of childhood often with an unfavourable outcome. One common genetic feature in aggressive tumours is 1p-deletion.  相似文献   
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