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21.
New device for percutaneous closure of aortopulmonary collaterals.   总被引:5,自引:0,他引:5  
A 4.5-month-old infant with tetralogy of Fallot, pulmonary atresia, and multiple aortopulmonary collaterals underwent successful occlusion of the collaterals using a new device. This new plug (Amplatzer vascular plug) is a self-expandable cylindrical device made of nitinol wire mesh. The device is available in sizes from 4 to 16 mm in 2 mm increment. The device can be used in patients with aortopulmonary collaterals, pulmonary arteriovenous malformations, venovenous collaterals, shunts, coronary fistulas, and certain type of patent ductus arteriosus.  相似文献   
22.

Background

Subdural fluid collections (hygromas and effusions) in adults are usually seen following head trauma or overdrainage of cerebrospinal fluid (CSF) after CSF diversion procedures. We report an unusual case of subdural fluid collection that developed spontaneously 5 days after an aneurysmal subarachnoid hemorrhage (SAH). This patient neither had permanent CSF diversion procedure nor history of significant head trauma during her clinical course.

Methods

This study is a Case report of the patient suffering from an SAH.

Results

A 71-year-old woman suffered an SAH from a ruptured right-sided posterior communicating artery aneurysm. Computed tomography (CT) demonstrated diffuse SAH and signs of early hydrocephalus that did not require treatment. The aneurysm was treated with endovascular coil occlusion without any complications. Throughout her hospital course, she remained alert without neurological deficits. A large subdural fluid collection was discovered incidentally during a routine CT scan of the brain 5 days after the SAH. The patient remained asymptomatic; therefore, the collection was treated conservatively. It resolved spontaneously at five days after the initial diagnosis.

Conclusion

Subdural fluid collections following SAH can occur as a result of head trauma, external hydrocephalus, or as a treatment complication of CSF shunting and craniotomies. It is critical to differentiate simple hygromas from external hydrocephalus since their response to CSF diversion is entirely different.  相似文献   
23.
Objectives: To investigate if it is possible to achieve complete decontamination of dental implant surfaces with different surface characteristics.

Materials and methods: Twelve implant pieces with an Osseotite® surface and 12 implant pieces with a Ti-Unite® surface were attached on to the complete lower dentures of six patients and were allowed to accumulate plaque for 30 days. When retrieved, the implant decontamination protocol used, involved both mechanical (PeriBrush?) and chemical (3% H2O2) decontamination. The number of colony forming units per millilitre was determined and the dominant micro-organisms in selected samples was identified by 16s rRNA gene amplicon sequencing. The effect of the titanium brush on the implant surface was examined by SEM.

Results: Complete decontamination was achieved in five out of 24 implants (four Osseotite® and one Ti-Unite®). The mean CFU/ml detected after decontamination were 464.48 for Osseotite® and 729.09 for Ti-Unite® implants. On the surface of the implants in which complete decontamination was not achieved, all of the predominant bacteria identified were streptococci except for one which was identified as micrococcus. SEM images revealed that the surface features of the decontaminated implants were not significantly altered.

Conclusions: Mechanical decontamination using a titanium brush supplemented with chemical treatment for one minute (3% H2O2) can achieve complete decontamination of implant surfaces in edentulous patients.  相似文献   
24.
25.
Retinal arterial macroaneurysms with supravalvular pulmonic stenosis (RAMSVPS), also known as Familial Retinal Arterial Macroaneurysms (FRAM) syndrome, is a very rare multisystem disorder. Here, we present a case series comprising ophthalmologic and systemic evaluation of patients homozygous for RAMSVPS syndrome causative IGFBP7 variant. New clinical details on 22 previously published and 8 previously unpublished patients are described. Age at first presentation ranged from 1 to 34 years. The classical feature of macroaneurysms and vascular beading involving the retinal arteries was universal. Follow up extending up to 14 years after initial diagnosis revealed recurrent episodes of bleeding and leakage from macroaneurysms in 55% and 59% of patients, respectively. The majority of patients who underwent echocardiography (18/23) showed evidence of heart involvement, most characteristically pulmonary (valvular or supravalvular) stenosis, often requiring surgical correction (12/18). Four patients died in the course of the study from complications of pulmonary stenosis, cerebral hemorrhage, and cardiac complications. Liver involvement (usually cirrhosis) was observed in eight patients. Cerebral vascular involvement was observed in one patient, and stroke was observed in two. We conclude that RAMSVPS is a recognizable syndrome characterized by a high burden of ocular and systemic morbidity, and risk of premature death. Recommendations are proposed for early detection and management of these complications.  相似文献   
26.
Although catheter-based intervention is generally accepted as the treatment of choice for branch pulmonary artery (PA) stenosis, there are no data directly comparing both the need for reintervention and time to reintervention in patients undergoing transcatheter stenting versus surgical arterioplasty. We compared children who underwent surgical branch pulmonary arterioplasty and branch PA stent placement between January 2008 and May 2012 at a single tertiary center. Need for reintervention and mean time to reintervention were assessed using chi-square and independent sample Student t test. Thirty-seven patients were included (surgery n = 18, stent n = 19). Mean weight at initial intervention was 11.3 ± 8.8 kg for surgical and 20.1 ± 15.5 kg for stent (p = 0.041). Intervention was performed on the left PA in 17 patients, the right PA in 12 patients, and both PAs in 8 patients. Five patients had undergone previous intervention. On mean follow-up of 807 ± 415 days, 50 % (9 of 18) of the surgery cohort and 5.3 % (1 of 19) of the stent cohort required reintervention (p = 0.002). In all but one case reintervention was catheter-based. Mean time to reintervention for the surgery cohort was 272 ± 162 days and for the single stent cohort it was 150 days. When comparable age and weight groups were analyzed, reintervention was still more common in the surgery cohort (p = 0.007). Children undergoing surgical branch pulmonary arterioplasty are more likely to require reintervention than those undergoing stent placement.  相似文献   
27.
28.
In ferromagnetic semiconductors, the coupling of magnetic ordering with semiconductor character accelerates the quantum computing. The structural stability, Curie temperature (Tc), spin polarization, half magnetic ferromagnetism and transport properties of ZnX2Se4 (X = Ti, V, Cr) chalcogenides for spintronic and thermoelectric applications are studied here by density functional theory (DFT). The highest value of Tc is perceived for ZnCr2Se4. The band structures in both spin channels confirmed half metallic ferromagnetic behavior, which is approved by integer magnetic moments (2, 3, 4) μB of Ti, V and Cr based spinels. The HM behavior is further measured by computing crystal field energy ΔE crystal, exchange energies Δ x(d), Δ x (pd) and exchange constants (No α and No β ). The thermoelectric properties are addressed in terms of electrical conductivity, thermal conductivity, Seebeck coefficient and power factor in within a temperature range 0–400 K. The positive Seebeck coefficient shows p-type character and the PF is highest for ZnTi2Se4 (1.2 × 1011 W/mK2) among studied compounds.  相似文献   
29.
Objectives:To assess how clinical services are accessed and utilized by young children with suspected autism spectrum disorder (ASD) and identifying factors that prevent the early identification of developmental concerns and diagnosis.Methods:This retrospective study examined the sociodemographic and clinical characteristics of a convenience sample of children diagnosed with ASD at the Center for Autism Research, Riyadh, Saudi Arabia between 2016 and 2018. The characteristics of ASD assessment and intervention service use were examined. Additionally, we examined the association between sociodemographic, clinical, and service use variables with the child’s age at the time of the parent’s initial concern and first ASD diagnosis, and the time from first concern to diagnosis.Results:Out of 127 cases, 67 were diagnosed with ASD (mean: 46.88 months, SD: 18.88, median: 42.00, range, 19-93). Most ASD cases had one previous assessment (n=28, 41.8%). Higher sibling numbers were associated with a later age of first concern (p=0.0278). Applied behavior analysis service utilization was associated with later age of first ASD diagnosis (p=0.0336) and longer time to ASD diagnosis (p=0.0301).Conclusion:Larger sample size is needed to further investigate whether these findings are representative of the national experience. Community-based intervention outcome studies should assess the quality of services being provided.  相似文献   
30.
BackgroundThis study investigates in‐hospital mortality amongst patients with severe acute respiratory syndrome coronavirus 2 (SARS‐CoV‐2) and its relation to serum levels of gamma‐glutamyl transferase (GGT).MethodsPatients were stratified according to serum levels of gamma‐glutamyl transferase (GGT) (GGT<50 IU/L or GGT≥50 IU/L).ResultsA total of 802 participants were considered, amongst whom 486 had GGT<50 IU/L and a mean age of 48.1 (16.5) years, whilst 316 had GGT≥50 IU/L and a mean age of 53.8 (14.7) years. The chief sources of SARS‐CoV‐2 transmission were contact (366, 45.7%) and community (320, 40%). Most patients with GGT≥50 IU/L had either pneumonia (247, 78.2%) or acute respiratory distress syndrome (ARDS) (85, 26.9%), whilst those with GGT<50 IU/L had hypertension (141, 29%) or diabetes mellitus (DM) (147, 30.2%). Mortality was higher amongst patients with GGT≥50 IU/L (54, 17.1%) than amongst those with GGT<50 IU/L (29, 5.9%). More patients with GGT≥50 required high (83, 27.6%) or low (104, 34.6%) levels of oxygen, whereas most of those with GGT<50 had no requirement of oxygen (306, 71.2%). Multivariable logistic regression analysis indicated that GGT≥50 IU/L (odds ratio [OR]: 2.02, 95% confidence interval [CI]: 1.20–3.45, p=0.009), age (OR: 1.05, 95% CI: 1.03–1.07, p<0.001), hypertension (OR: 2.06, 95% CI: 1.19–3.63, p=0.011), methylprednisolone (OR: 2.96, 95% CI: 1.74–5.01, p<0.001) and fever (OR: 2.03, 95% CI: 1.15–3.68, p=0.016) were significant predictors of all‐cause cumulative mortality. A Cox proportional hazards regression model (B = −0.68, SE =0.24, HR =0.51, p = 0.004) showed that patients with GGT<50 IU/L had a 0.51‐times lower risk of all‐cause cumulative mortality than patients with GGT≥50 IU/L.ConclusionHigher levels of serum GGT were found to be an independent predictor of in‐hospital mortality.  相似文献   
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