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71.
MMPI profiles of disability insurance claimants   总被引:2,自引:0,他引:2  
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The spinocerebellar ataxias (SCAs) are progressive neurodegenerative disorders linked to more than 20 genetic loci. Most often, these diseases are caused by expansion of triplet repeats encoding polyglutamine (polyQ) tracts. The phenotype is variable and can cause a disease that overlaps clinically with Parkinson's disease (PD). l-Dopa-responsive parkinsonism with minimal cerebellar deficits has been described in SCA2 and SCA3. In order to define if mutation at these loci is a common cause of clinically defined parkinsonism we typed the SCA-2 and SCA-3 repeats for expansion in a series of 280 patients diagnosed with PD or parkinsonism. We identified one pathogenic expansion in SCA-2 in a North American family with autosomal dominant parkinsonism.  相似文献   
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Fatigue of the lumbar extensor muscles has been associated with a degradation of balance, but the mechanism is not well understood. The ankle plays a major role in upright standing, and loss of proprioceptive acuity at the ankle could contribute to a degradation of balance. Therefore, the first objective of this study was to investigate the effect of lumbar extensor fatigue on ankle proprioceptive acuity. The second objective was to investigate the effect of circumferential ankle pressure (CAP) on ankle proprioceptive acuity to evaluate CAP as a potential intervention to mitigate any loss of proprioceptive acuity at the ankle with lumbar extensor fatigue. To address these objectives, ankle joint motion sense was evaluated with and without CAP, both before and after the lumbar extensors were fatigued. Results showed an impairment in joint motion sense with both fatigue and CAP. These results indicate that lumbar extensor fatigue impairs ankle proprioceptive acuity, which may help explain observed increases in postural sway subsequent to lumbar extensor fatigue.  相似文献   
75.
We find that CD11c(+) cells with many markers of dendritic cells (DCs) are a major cell type in the skin lesions of psoriasis. These CD11c(+) cells, which are evident in both epidermis and dermis, are the sites for the expression of two mediators of inflammation, inducible nitric oxide synthase (iNOS) and TNF-alpha in diseased skin. These cells express HLA-DR, CD40, and CD86, lack the Langerin and CD14 markers of Langerhans cells and monocytes, respectively, and to a significant extent express the DC maturation markers DC-LAMP and CD83. Treatment of psoriasis with efalizumab (anti-CD11a, Raptiva) strongly reduces infiltration by these DCs in patients responding to this agent. Disease activity after therapy was more related to DC infiltrates and iNOS mRNA levels than T cell infiltrates, and CD11c(+) cells responded more quickly to therapy than epidermal keratinocytes. Our results suggest that a type of DC, which resembles murine "Tip-DCs" that can accumulate during infection, has proinflammatory effects in psoriasis through nitric oxide and TNF-alpha production, and can be an important target for suppressive therapies.  相似文献   
76.
BACKGROUND: Subcutaneous administration of low molecular weight heparin (eg, enoxaparin) has been shown to be safe and effective in the prevention of acute venous thromboembolic (TE) disease following acute spinal cord injury (SCI) in the rehabilitation setting. However, emerging evidence suggests that different dosing strategies may be equivalent. OBJECTIVE: To determine whether subcutaneous enoxaparin, 40 mg once daily, when compared with subcutaneous enoxaparin, 30 mg twice daily, is equally safe and effective in the prevention of venous TE disease in patients with SCI. DESIGN: Retrospective chart review. SETTING: A freestanding, inpatient, acute, rehabilitation hospital. PATIENTS: One hundred and twenty-nine patients admitted from June 2000 through June 2002 for inpatient rehabilitation following an acute SCI who received either enoxaparin, 40 mg once daily, or enoxaparin, 30 mg twice daily, for prophylaxis for TE disease. RESULTS: Equivalent prophylaxis efficacy was seen in both enoxaparin groups. Symptomatic venous thromboembolism did not differ, with deep vein thromboses occurring in 1 of 49 (2.0%) patients receiving twice-daily enoxaparin, and 1 of 80 (1.25%) patients receiving once-daily enoxaparin (chi2 = 0.125, NS). Pulmonary embolism was seen in 1 of 49 (2.0%) patients treated with twice-daily enoxaparin and in none of the patients in the once-daily group (chi2 = 1.64, NS). Bleeding complications also did not differ between the 2 treatment groups; these were observed in 2 of 49 (4.1%) patients receiving twice-daily enoxaparin and in 5 of 80 (6.3%) patients receiving once-daily enoxaparin (chi2 = 0.228, NS). CONCLUSION: Subcutaneous enoxaparin administered once or twice daily is equally effective for the prevention of venous TE disease. Both dosing strategies are associated with a low incidence of bleeding in patients with SCI who are undergoing rehabilitation.  相似文献   
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OBJECTIVE: To compare testicular color Doppler sonography with testicular scintigraphy in differentiating between surgical and nonsurgical conditions of the pediatric testis, and to evaluate the role of testicular color Doppler sonography in the pediatric population. MATERIALS AND METHODS: Forty-six children (age range, 1 day to 18 years; median age, 11 years) with acute scrotal pain were evaluated with both scintigraphy and color Doppler sonography by two separate groups of radiologists who had no knowledge of the results of the other modality. The final radiologic diagnosis was classified as a surgical condition, nonsurgical condition, or indeterminate and was compared with the patient's surgical diagnosis or clinical diagnosis, which was established by response to treatment and follow-up. RESULTS: Sonography correctly diagnosed 11 of 14 surgical conditions and 31 of 32 nonsurgical conditions. There was one indeterminate sonogram. There were no false-positive examinations, and there were three false-negative examinations (sensitivity = 78.6% [95% CI, 66.7-90.5%], specificity = 96.9% [95% CI, 94.3-99.5%], accuracy = 91.3%). Color flow was demonstrated in the asymptomatic testis in 34 of 44 boys. Scintigraphy correctly diagnosed 11 of 14 surgical conditions and 29 of 32 nonsurgical conditions. There were two indeterminate scintigrams. There were two false-positive examinations and two false-negative examinations (sensitivity = 78.6% [95% CI, 66.7%-90.5%], specificity = 90.6% [95%CI, 82.2%-99.0%], accuracy = 87.0%). CONCLUSIONS: Color Doppler sonography and scintigraphy show similar sensitivity for the diagnosis of testicular torsion. A small number of false-negative cases can occur with either modality. The two studies may provide complementary information in indeterminate cases.  相似文献   
80.
Nussbaum ES  Mendez A  Camarata P  Sebring L 《Neurosurgery》2003,53(4):831-4; discussion 834-5
OBJECTIVE: To describe the management and outcomes of seven patients with fusiform aneurysms of the peripheral posteroinferior cerebellar artery (PICA). METHODS: Medical records and neuroimaging studies of seven patients who underwent surgical treatment of fusiform aneurysms of the peripheral PICA were reviewed. Average follow-up time was 1.5 years, and no patient was lost to follow-up. RESULTS: All patients presented with acute subarachnoid hemorrhage, and most had acute hydrocephalus. All underwent surgery, which entailed distal revascularization in six of the seven patients. Revascularization techniques included occipital artery-PICA bypass, side-to-side PICA-PICA anastomosis, and aneurysm excision with direct end-to-end PICA reanastomosis. Outcome was good in six patients and fair in one. CONCLUSION: Fusiform, peripheral PICA aneurysms are rare lesions. Distal revascularization was used in most cases because of the uncertain adequacy of collateral supply. Careful, individualized management allows for a good outcome in the majority of cases.  相似文献   
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