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81.
82.
Prephan L 《AORN journal》2005,81(5):1015-22; quiz 1025-8
SURGICAL INSTRUMENT AVAILABILITY often is at the top of the list for perioperative quality improvement projects.
ENSURING AVAILABILITY of surgical instruments can be a daily struggle. At one facility, searching for items shortly before a procedure was a common occurrence.
THIS ARTICLE DESCRIBES a three-year quality improvement project undertaken to improve instrument availability throughout surgical services. The article also includes future plans and lessons learned. AORN J 81 (May 2005) 1017-1022.
  相似文献   
83.
A supplementation trial starting with 224 postmenopausal women provided with adequate vitamin D and Ca was conducted to determine whether increased Cu and Zn intakes would reduce the risk for bone loss. Healthy women aged 51-80 years were recruited for a double-blind, placebo-controlled study. Women with similar femoral neck T scores and BMI were randomly assigned to two groups of 112 each that were supplemented daily for 2 years with 600?mg Ca plus maize starch placebo or 600?mg Ca plus 2?mg Cu and 12?mg Zn. Whole-body bone mineral contents, densities and T scores were determined biannually by dual-energy X-ray absorptiometry, and 5?d food diaries were obtained annually. Repeated-measures ANCOVA showed that bone mineral contents, densities and T scores decreased from baseline values to year 2. A priori contrasts between baseline and year 2 indicated that the greatest decreases occurred with Cu and Zn supplementation. Based on 5?d food diaries, the negative effect was caused by Zn and mainly occurred with Zn intakes ≥?8·0?mg/d. With Zn intakes 相似文献   
84.
Hemivertebral excision for congenital scoliosis in very young children.   总被引:12,自引:0,他引:12  
The present study reports the results of a consecutive series of six very young children who underwent single-anesthetic sequential anterior and posterior hemivertebral excision. The children, all less than 34 months old (mean age 19 months), presented with high magnitude or progressive congenital scoliosis related to an unbalanced hemivertebra. Curve correction required hemivertebral excision, which was accomplished during a single operative event using sequential anterior and posterior procedures. The intraoperative curve correction was maintained with plaster immobilization for 3 months. All patients were followed for at least 24 months. Pre-and postoperative spinal radiographs were analyzed for initial and final curve correction. Excellent correction of preoperative deformity was obtained and maintained throughout the follow-up period. The mean postoperative curve correction (67%; range 52%-84%) compared favorably with the average correction at final follow-up (70%; range 50%-85%). Radiographs revealed a consistently solid arthrodesis with no evidence of curve progression. There were no neurologic or other significant complications. In conclusion, single-anesthetic sequential anterior and posterior hemivertebral excision appears to be a safe and efficacious procedure for the management of congenital scoliosis in very young children.  相似文献   
85.
STUDY DESIGN: Synthetic spine models were used to compare the effects of hook pattern and kyphotic angulation on stiffness and rod strain in long-segment posterior spinal constructs. OBJECTIVES: To examine the biomechanical effects of hook patterns and kyphotic angulation on long-segment posterior spinal constructs. SUMMARY OF BACKGROUND DATA: Kyphotic deformities managed by increasing rod diameter and hence construct stiffness have shown decreased postoperative loss of correction and hardware complications. The biomechanical effects of hook pattern and kyphosis are unknown. METHODS: Spine models of 0 degrees, 27 degrees 54 degrees sagittal contour, composed of polypropylene vertebral blocks and isoprene elastomer intervertebral spacers, representing T3-T12, were used for biomechanical testing of long-segment posterior spinal constructs. Models were instrumented with 6.35-mm titanium rods and one of the following hook configurations: 20-hook compression, 16-hook compression, 16-hook claw apex-empty,16-hook claw apex-full, or 8-hook claw. Construct stiffness and rod strain during axial compression were determined. RESULTS: The compression-hook patterns provided at least a 45% increase in construct stiffness (P = 0.013)and a 22% decrease in rod strain (P < 0.0001) compared with those obtained with the claw-hook pattern with the best biomechanical performance. When analyzing all five hook patterns, there was a 19% decrease in construct stiffness and 27% increase in rod strain when progressing from straight alignment to 27 degrees of sagittal contour (P < 0.0001). Progressing from straight alignment to 54 degrees decreased construct stiffness by 48% and increased rod strain by 55% (P < 0.0001). Construct stiffness was inversely correlated to rod strain in all five hook patterns (R2 = 0.82-0.98, P < 0.001). CONCLUSIONS: Using compressive-hook patterns and decreasing the kyphotic deformity significantly increases construct stiffness and decreases rod strain.  相似文献   
86.
Interleukin-12 (IL-12) is one of the first cytokines produced by macrophages, key mediators of innate resistance, during the host’s immune response to infections. Therefore, in this study we propose that IL-12 has an important role in the early phase of the immune response to Mycobacterium bovis BCG. IL-12 has been shown to enhance the maturation of protective Th1 cells and gamma interferon (IFN-γ) production during mycobacterial infection. Therefore, it may play a crucial role during the immune phase of infection as well. To examine the role of IL-12 in both the innate and the immune phase of infection, we compared BCG-resistant mice, B10.A (Bcgr), to the susceptible congenic strain B10.A (Bcgs) following administration of a blocking monoclonal antibody to IL-12 (10F6). Anti-IL-12-treated susceptible animals exhibited a two- to threefold increase in spleen CFU by day 21. In contrast, anti-IL-12 treatment had little or no effect on the response of the genetically resistant animals to infection. The B10.A (Bcgr) but not the B10.A (Bcgs) mice had an increase in IFN-γ mRNA relative to baseline levels as early as day 1 of infection irrespective of anti-IL-12 treatment. By day 14, B10.A (Bcgr) mice showed a decrease in IFN-γ mRNA while the B10.A (Bcgs) mice showed a significant increase in IFN-γ mRNA levels. Thus, during BCG infection, the B10.A (Bcgr) mice mount an early IFN-γ response against BCG whereas the B10.A (Bcgs) mice have a delayed IFN-γ response correlating with their genetic permissiveness expressed as an increased mycobacterial load by day 21. Overall, our data demonstrate that the inherent resistance of B10.A (Bcgr) mice to mycobacteria does not depend on optimal levels of IL-12 to maintain effective control of the bacteria, whereas IL-12 is important for the susceptible animals’ response to BCG during the peak of infection.  相似文献   
87.
Synaptic defects at meiosis I and non-obstructive azoospermia   总被引:2,自引:0,他引:2  
BACKGROUND: Recent advances in immunofluorescence methodology have made it possible to directly monitor protein localization patterns in germ cells undergoing meiosis. We used this technology to examine the early stages of meiosis in testicular material obtained from men presenting for evaluation at infertility clinics. METHODS: Specifically, we compared meiotic progression, synapsis and recombination in 34 individuals with obstructive azoospermia ('controls') to 26 individuals with non-obstructive azoospermia (NOA) ('cases'). RESULTS: In 9 of the 26 cases, no germ cells were identified, but in the remaining 17, there was at least some progression through meiosis. Most of these individuals appeared to have normal levels of spermatogenic activity, with little evidence of meiotic impairment. However, in three individuals, we observed either complete or partial meiotic arrest associated with abnormalities in synapsis. CONCLUSIONS: This suggests that >10% of cases of unexplained NOA may be attributable to severe meiotic defects. The characterization of these meiotic arrest phenotypes may guide further research into the molecular basis of unexplained infertility.  相似文献   
88.
The dual goals of the faculty Fellowship in Medical Education (MEF) program at the David Geffen School of Medicine at UCLA, established in 1992, are to prepare excellent teachers to serve as clerkship chairs, course chairs, or residency program directors while strengthening their dossiers for promotion based on a scholarly approach to curriculum development, implementation, and evaluation. Fellows are nominated from their departments and must demonstrate a strong interest in assuming educational leadership in their respective specialties. A total of eight fellows are accommodated each year based on interviews with the MEF faculty. The two-year program consists of two seminars and two projects focused on four objectives: to critique teaching and testing practices in medical education in light of current theories of learning; to develop and implement curricula that reflect these theories; to improve personal teaching skills through reflection and feedback; and to design and conduct an educational research or program evaluation study. An analysis of the curricula vitae of faculty members who have completed the fellowship suggest that this program continues to provide educational leaders for the school as originally intended. Of the 71 medical school faculty members who completed the MEF between 1993 and 2004 and have remained at the university, 43 (61%) have assumed new leadership roles in medical education. The evaluation data strongly suggest that the MEF has had a major role since its inception in creating a pool of faculty members with the confidence to manage the tasks of educational planning and implementation.  相似文献   
89.
OBJECTIVE: We determined the effect of clothing type on the validity of air-displacement plethysmography (ADP) to estimate percentage of body fat (%BF) and ascertain if these effects differ by body mass index (BMI). METHODS: The %BF by dual x-ray absorptiometry (DXA) and %BF, density, and body volume by ADP were assessed in 132 healthy adults classified by normal (N; 18.5-24.9 kg/m2), overweight (OW; 25-29.9 kg/m2), and obese (OB; 30-39.9 kg/m2) BMIs. RESULTS: Compared with DXA, ADP underestimated (P < 0.0001) %BF from scrubs (SC) and t-shirt/shorts (TS) in N (11.4%; 8.6%) and OW (6.8%; 4.9%) BMI groups, respectively. ADP compared with DXA overestimated (P < 0.0006) %BF in the OW group (1.2%), but underestimated (P < 0.0001) it in the N group (2.4%). ADP also overestimated (P < 0.006) %BF in the OB group wearing spandex (SP; 4.8%), but not in those wearing SC (0.7%; P = 0.10) and TS (0.5%; P = 0.22) versus DXA. CONCLUSION: All three clothing types showed significant error in estimating %BF with ADP compared with DXA in N and OW BMI. Use of spandex provided the least error and is the preferred attire to obtain valid body composition results when testing N and OW subjects. However, SP provided the greatest error in the OB group. Error in ADP %BF in OB was minimal in SC and TS and similar to the within-subject variability in %BF estimates with ADP. Thus, TS and SC are acceptable alternatives to SP in adults with excess body weight.  相似文献   
90.

Background and Purpose

The electrocardiogram (ECG) is commonly used as a screening tool for diagnosis of the ostium secundum atrial septal defect (ASD). We sought to analyze the utility of conventional ECG criteria in detecting right ventricular enlargement (RVE) due to the presence of an ASD.

Methods

Patients who underwent transcatheter or surgical closure of an isolated ASD between 1997 and 2004 were included if an ECG was performed less than 9 months before ASD closure and had echocardiographic RVE.

Results

Of 99 children (aged 6.8 ± 4.7 years; range, 1-18 years) with RVE and ASD, 57% had an ECG that met 1 or more RVE criteria. The sensitivity of ECG increased to 70% in younger patients and to 80% for the largest defects.

Conclusions

Electrocardiographic criteria for RVE are present in just more than over half of young patients with large ASDs. Although ECG is more sensitive in younger patients, it is unreliable as a screen for this lesion.  相似文献   
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