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排序方式: 共有818条查询结果,搜索用时 31 毫秒
41.
42.
Primary intraosseous meningioma: CT and MRI appearance   总被引:5,自引:0,他引:5  
Benign primary intraosseous meningioma presenting with osteolytic skull lesion and soft-tissue component is rare. CT and MR imaging of a patient with frontoparietal scalp swelling showed an osteolytic intracalvarial lesion with an extradural soft-tissue component. Following wide surgical resection, the histological examination revealed an intraosseous chordoid meningioma. The clinical and radiological findings of primary intraosseous meningioma are discussed and the relevant literature is reviewed.  相似文献   
43.
OBJECTIVES: Surface electromyographic (sEMG) studies were performed on 100 normal children, age 4-12 years, to establish normative database for duration and amplitude of muscle activity during swallowing and continuous drinking. STUDY DESIGN: Prospective observational study of healthy volunteers. METHODS: Parameters evaluated during swallowing include the timing and amplitude (in microV) of activity of m. orbicularis oris, masseter, submental and infrahyoid (laryngeal strap muscles (LSM)) groups covered by platisma. Four tests were examined: voluntary single swallows of saliva ("dry" swallow), voluntary single water swallows as normal, voluntary single swallows of excessive amount of water (up to 15ml), continuous drinking of 50ml of water (duration and number of swallows). Duration of muscle activity during swallowing (mean plus standard deviation (S.D.)) was measured for two age groups: 4-8 and 9-12 years old. The group of 40 adults, age 18-30 years, was taken as a control group. RESULTS: Normative data for duration and amplitude of muscle activity during single swallowing and continuous drinking are established for healthy children. The duration of muscle activity during swallows and drinking in all tests showed decrease with the age, and this tendency is statistically significant (one-dimensional analysis of variance, SPSS, chi(2) criterion, 95% confidence interval). There was no statistically significant difference in amplitude (range) measurements between children and adults (P=0.05). There was no statistically significant difference between male and female children duration of muscle activity during single swallowing and continuous drinking in all age groups (P>/=0.05). CONCLUSION: Surface EMG of swallowing is a simple and reliable noninvasive method for screening evaluation of swallowing with low level of discomfort of the examination. The normative timing of events data can be used for evaluation of complaints and symptoms, as well as for comparison purposes in pre- and postoperative stages and in electromyography (EMG) monitoring during ENT or neurological treatment. These parameters represent normal deglutition, and can be used to identify abnormalities in pediatric patients, and provide a basis for comparison of swallowing performance, both within and between patients.  相似文献   
44.
Vaiman M  Eviatar E  Segal S 《Rhinology》2004,42(3):145-152
OBJECTIVES: The purpose of this paper is to describe the outcome of muscle-building therapy for nasal muscles in cases of nasal valve stenosis or collapse. The present study was performed to investigate the best way to combine transcutaneous and intranasal surface electromyography (sEMG) biofeedback training of muscles involved in nasal valve function with a home exercise program and electric stimulation of nasal muscles. METHODS: A randomized pilot study of 3 groups of patients (n1=12, n2=12, n3=10; total 34 patients) presenting with symptoms of obstructed nasal breathing was conducted. All selected patients demonstrated nasal valve stenosis with a positive Cottler maneuver and clinically evident nasal valve collapse. Follow-up ranged from 8 to 12 months. Treatment for Group 1 included transcutaneous and intranasal electric stimulation of nasal muscles only. Treatment for Group 2 included biofeedback training and home exercise program of specific nasal movements, and treatment for Group 3 included surface and intranasal EMG biofeedback assisted specific strategies for nasal muscle education, home exercises and electric stimulation. RESULTS: All patients in these groups exhibited subjective improvement. For Group 3, in 80% the improvement was proved objectively; for Group 2, in 75% the improvement was proved objectively; for Group 1, in 58,33% the improvement was proved objectively. We found no significant difference between the results in Groups 3 and 2 and poorer results in Group 1. CONCLUSION: Relieve of nasal valve stenosis and collapse can be achieved with a complex muscle-building therapy as described. It helps a significant cohort of patients with symptoms of obstructed nasal breathing to avoid surgical intervention. Electric stimulation of the muscles does not contribute significantly in achieving of good results.  相似文献   
45.
Myofibromas are benign mesenchymal tumors that are commonly found in the dermis and subcutaneous tissues of the head and neck. Although most lesions are recognized during infancy and early childhood, several cases have been reported in older children and adults. We describe the case of a 9-year-old girl who presented with a solitary nodule in the left cheek and a history of minor trauma. Preoperative imaging detected the presence of a subcutaneous soft-tissue mass consistent with a soft-tissue neoplasm rather than a hematoma. Analysis of fine-needle aspiration material was nondiagnostic. Incisional biopsy revealed that the lesion was a myofibroma.  相似文献   
46.
Lossos A  Ashhab Y  Sverdlin E  Amir G  Ben-Yehuda D  Siegal T 《Cancer》2004,101(8):1843-1849
BACKGROUND: Central nervous system involvement is a well recognized complication of systemic non-Hodgkin lymphoma. Most central nervous system recurrences occur within the first 2 years after the initial diagnosis and are considered to represent clonally related recurrence of systemic disease. The authors attempted to investigate the clonal relation between the late-delayed central nervous system involvement and the original systemic tumor. METHODS: The authors studied archival, formalin fixed, paraffin embedded tissue samples from 8 patients with isolated cerebral involvement diagnosed > 3 years after their initial presentation with aggressive, systemic, B-cell non-Hodgkin lymphoma. The rearranged immunoglobulin heavy-chain variable region genes (VH) from both sites were amplified by polymerase chain reaction and were sequenced when necessary. RESULTS: In three of five patients who had interpretable results, a distinct, monoclonal, VH family-specific band profile was obtained from the cerebral and systemic lymphoma. In the other two patients, a similar VH band pattern was observed and also was compared using direct sequencing, which demonstrated sequence differences between tumors from the two sites. CONCLUSIONS: Clonal variance between the cerebral and systemic lymphoma in these patients suggested the possibility that some instances of late-delayed recurrence in the central nervous system represent a second, new B-cell lymphoma rather than a true recurrence of the original systemic tumor, a finding that may have significant clinical and biologic implications.  相似文献   
47.
Semaphorin-3F is an inhibitor of tumor angiogenesis   总被引:15,自引:0,他引:15  
The neuropilin-1 (np1) and neuropilin-2 (np2) receptors form complexes with type-A plexins. These complexes serve as signaling receptors for specific class-3 semaphorins. Np1 and np2 function in addition as receptors for heparin-binding forms of vascular endothelial growth factor (VEGF), such as VEGF(165). Human umbilical vein endothelial cells (HUVEC) express tyrosine-kinase receptors for VEGF and basic fibroblast growth factor (bFGF), as well as np1, np2, and several type-A plexins. We have found that semaphorin-3F (s3f), a semaphorin which signals through the np2 receptor, was able to inhibit VEGF(165), as well as bFGF-induced proliferation of HUVECs. Furthermore, s3f inhibited VEGF as well as bFGF-induced phosphorylation of extracellular signal-regulated kinase-1/2. Our experiments indicate that bFGF does not bind to neuropilins, nor does s3f inhibit the binding of bFGF to FGF receptors. It is therefore possible that s3f inhibits the activity of bFGF by a mechanism that requires active s3f signal transduction rather than by inhibition of bFGF binding to FGF receptors. s3f also inhibited VEGF(165), as well as bFGF-induced in vivo angiogenesis as determined by the alginate micro-encapsulation and Matrigel plug assays. Overexpression of s3f in tumorigenic human HEK293 cells inhibited their tumor-forming ability but not their proliferation in cell culture. The tumors that did develop from s3f-expressing HEK293 cells developed at a much slower rate and had a significantly lower concentration of tumor-associated blood vessels, indicating that s3f is an inhibitor of tumor angiogenesis.  相似文献   
48.
PURPOSE: The impact of out-of-pocket expenses on five domains of family lifestyle were explored: social, assets, credit, utilities, and charity. METHODS: Using a cross-sectional survey, 100 parents of pediatric cancer patients reported on the types of out-of-pocket expenses incurred and the perceived lifestyle impact of meeting those expenses. RESULTS: Eighty percent of the sample reported a minimum of five different out-of-pocket expenses (total mean value = 19,064 Australian dollars; approximately 9,723 US dollars). The majority reflected travel, accommodation, and communication costs, use of work-related entitlements, and changes in paid employment. In lifestyle terms, the area of greatest impact was found for the social domain, such as cancelling vacations and giving up recreational pleasures and social expenditure. Those families living furthest from the major cancer treatment center reported the greatest range of out-of-pocket expenses and subsequent lifestyle impact. While there were few differences as a function of cancer type, results suggested that families most vulnerable to financial distress tended to be those whose child had spent relatively longer on treatment. CONCLUSIONS: In meeting out-of-pocket expenses, parents primarily seek ways to "trim the fat" off existing family expenditure. While all families may incur extra expenses, parents of patients located a significant distance from the cancer treatment center remain especially vulnerable (despite increased government allowances). Creative solutions for addressing some expenses may include applications of telemedicine to augment outreach services.  相似文献   
49.
The treatment of primary central nervous system lymphoma (PCNSL) has centered around high-dose methotrexate and radiotherapy (RT). Methotrexate administered intra-arterially (IA) with blood-brain barrier disruption (BBBD) and without RT, has been a highly effective treatment with a 5 year survival of 42% without cognitive loss. The purpose of this analysis is to determine responses for patients with relapsed PCNSL treated with second line IA carboplatin-based chemotherapy with BBBD. Between February 1991 and April 2000, 37 relapsed PCNSL patients, most who failed front line therapy with methotrexate based chemotherapy, were treated at Oregon Health & Science University (OHSU) and Hadassah Hebrew University Hospital (HHUH) with IA carboplatin-based chemotherapy with BBBD. Nine patients had prior RT. The mean age was 57.5 years, and all but 1 patient were treated within 8 months after relapse. The median time for survival from first IA carboplatin/BBBD treatment was 6.8 months;however, 7 out of 37 patients survived > or = 27 months. Nine patients had radiographic complete response (CR), 4 patients had radiographic partial response (PR), 12 had stable disease (SD), 10 had progressive disease (PD), and 2 were non-evaluable. The median time to failure for patients with CR and PR was 9.1 months. One long-term survivor is alive at 91.0 months from first carboplatin/BBBD treatment. In conclusion, we show that relapsed PCNSL has shown sensitivity to second line IA carboplatin-based chemotherapy with BBBD. We have developed a new protocol using i.v. rituximab prior to BBBD with IA carboplatin, i.v. cyclophosphamide and i.v. etoposide phosphate. The long-term program goal is to consolidate dose-intensive chemotherapy with monoclonal antibody directed radiation. Because patients with recurrent PCNSL commonly continue to relapse even after obtaining a complete response to enhanced chemotherapy treatment, patients w ho complete or fail the above carboplatin/BBBD treatment regimen will be offered consolidation with radioimmunotherapy using zevalin (Ibritumomab tiuxetan), IDEC-2B8 conjugated with yttrium-90 (90Y).  相似文献   
50.
The effects of weight loss on renal function in patients with severe obesity   总被引:20,自引:0,他引:20  
Severe obesity is associated with increased renal plasma flow (RPF) and glomerular filtration rate (GFR). The aim of the present study was to examine whether weight loss may reverse glomerular dysfunction in obese subjects without overt renal disease. Renal glomerular function was studied in eight subjects with severe obesity (body mass index [BMI] 48.0 +/- 2.4) before and after weight loss. Nine healthy subjects served as controls. GFR and RPF were determined by measuring inulin and PAH clearance. In the obese group, GFR (145 +/- 14 ml/min) and RPF (803 +/- 39 ml/min) exceeded the control value by 61% (90 +/- 5 ml/min, P = 0.001) and 32% (610 +/- 41 ml/min, P < 0.005), respectively. Consequently, filtration fraction was increased. Mean arterial pressure, although normal, was higher than in the control group (101 +/- 4 versus 86 +/- 2 mmHg, P < 0.01). After weight loss, BMI decreased by 32 +/- 4%, to 32.1 +/- 1.5 (P = 0.001). GFR and RPF decreased to 110 +/- 7 ml/min (P = 0.01) and 698 +/- 42 ml/min (P < 0.02), respectively. Albumin excretion rate decreased from 16 microg/min (range, 4 to 152 microg/min) to 5 microg/min (range, 3 to 37 microg/min) (P < 0.01). Fractional clearance of albumin decreased from 3.2 x 10(-6) (range, 1.1 to 23 x 10(-6)) to 1.2 x 10(-6) (range, 0.5 to 6.8 x 10(-6)) (P < 0.02). This study shows that obesity-related glomerular hyperfiltration ameliorates after weight loss. The improvement in hyperfiltration may prevent the development of overt obesity-related glomerulopathy.  相似文献   
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