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51.
We studied the variability in saccades by comparing the peak velocities of saccades with the same target amplitude made with different actual amplitudes. We tested three hypotheses: the pulse-height noise hypothesis (peak velocity and amplitude vary proportionally), the localization noise hypothesis (variability in amplitude and peak velocity lie along the main sequence), and the independent noise hypothesis (variability in amplitude and peak velocity are independent). We measured eye orientation in two experiments by a scleral coil and a video system. Surprisingly, the main source of variability of saccades depended on the measurement system used. A combination of localization noise and independent noise best describes the data obtained by the video system. The independent noise (e.g., measurement inaccuracy) was the main source of variability. For the scleral coils, the variability was considerably larger than for the less accurate video system. The pulse-height noise hypothesis best describes this additional variability. Therefore we conclude that pulse-height noise is the main source of variability in saccades measured with scleral coils. We discuss the influence of scleral coils on saccade generation and suggest that a change in motor strategy due to the discomfort of wearing the coils might be the cause of the increased variability.  相似文献   
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Neurothekeoma of the paranasal sinuses in a 3-year-old boy   总被引:3,自引:0,他引:3  
Neurothekeoma is a benign soft tissue tumor commonly located on the skin. In this report, a 3-year-old boy presented with restricted right eye movement and decrease in visual acuity. The patient was found to have a 6-cm neurothekeoma involving the maxillary and ethmoid sinuses. To our knowledge, this is the first reported case of neurothekeoma with involvement of the maxillary and ethmoid sinuses. This uncommon lesion should be considered as the differential diagnosis of pediatric soft tissue tumors in the head and neck region.  相似文献   
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PURPOSE: The purpose of the present investigation was to examine to what extent precision data from 3-dimensional planning software for oral implants can be transferred to the operative field by means of a drilling template, containing high-precision drilling sleeves, fitted on the jawbone. It was investigated whether this procedure would allow advance preparation of a fixed definitive prosthesis that could be placed at the completion of surgery. MATERIALS AND METHODS: This procedure was experimentally carried out in 2 cadavers and later in 8 consecutive human patients. RESULTS: The results indicated a nearly perfect match between the positions and axes of the placed implants and those planned. DISCUSSION: This procedure permitted the placement of a definitive fixed prosthesis with limited freedom of space between the abutments and the metallic cylinders incorporated into the prosthesis. CONCLUSION: These encouraging results of the Leuven information technology-based oral rehabilitation by means of implants (LITORIM) are presently being further investigated at the clinical level.  相似文献   
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BACKGROUND: Adjuvant chemotherapy has been suggested as a possible strategy to improve survival in women with early-stage ovarian cancer; however, all randomized studies to date have been too small to answer this question reliably. METHODS: We performed a preplanned combined analysis of two parallel randomized clinical trials (International Collaborative Ovarian Neoplasm 1 [ICON1] and Adjuvant ChemoTherapy In Ovarian Neoplasm [ACTION]) in early-stage ovarian cancer that compared platinum-based adjuvant chemotherapy with observation following surgery. Between November 1990 and January 2000, 925 patients (477 in ICON1 and 448 in ACTION) who had surgery for early-stage ovarian cancer were randomly assigned to receive platinum-based adjuvant chemotherapy (n = 465) or observation (n = 460) until chemotherapy was indicated. Kaplan-Meier analysis was used to compare overall and recurrence-free survival by treatment allocation. In subgroup analyses of pretreatment age, tumor stage, histologic cell type, and differentiation grade, the differences in relative size of effect were tested using a chi-square test for interaction or a chi-square test for trend. All tests of statistical significance were two-sided. RESULTS: After a median follow-up of over 4 years, 245 patients had died or had a recurrence (ICON1: 133, ACTION: 112). Overall survival at 5 years was 82% in the chemotherapy arm and 74% in the observation arm (difference = 8% [95% confidence interval (CI) = 2% to 12%]; hazard ratio [HR] = 0.67, 95% CI = 0.50 to 0.90; P =.008). Recurrence-free survival at 5 years was also better in the adjuvant chemotherapy arm than it was in the observation arm (76% versus 65%, difference = 11% [95% CI = 5% to 16%]; HR = 0.64, 95% CI = 0.50 to 0.82; P =.001). Subgroup analyses provided no evidence of a difference in the size of effect of chemotherapy on survival in any pretreatment subcategory. CONCLUSIONS: Platinum-based adjuvant chemotherapy improved overall survival and recurrence-free survival at 5 years in this combined group of patients with early-stage ovarian cancer defined by the inclusion criteria of the ICON1 and ACTION trials.  相似文献   
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Background

When peritoneal carcinomatosis (PC) is diagnosed during emergency surgery for colorectal cancer (CRC), further treatment with curative intent may seem futile given the known poor prognosis of both PC and emergency surgery. The aim of the current study was to investigate the feasibility and effectiveness of cytoreductive surgery (CRS) and hyperthermic intraperitoneal chemotherapy (HIPEC) for CRC patients who previously underwent emergency surgery in the presence of PC.

Methods

All patients with synchronous PC of CRC referred to two tertiary centers between April 2005 and November 2013 were included in this study. Operative, postoperative and survival details were compared between patients presenting in an emergency or elective setting.

Results

In total, 149 patients with synchronous PC underwent CRS and HIPEC. Amongst these patients, 36 (24.2 %) initially presented with acute symptoms requiring emergency surgery. Acute presentation did not result in a longer interval between the initial operation and HIPEC (2.2 vs. 2.1 months; P = 0.09). When comparing operative outcomes, no significant differences were found in blood loss (P = 0.47), operation time (P = 0.39), or completeness of cytoreduction (P = 0.97). In addition, complication rates, degree and types of complication did not differ between the groups. Median survival was 36.1 months for emergency presentation compared with 32.1 in the elective group (P = 0.73).

Conclusion

CRS + HIPEC may be performed safely in patients with PC of colorectal origin presenting with acute symptoms requiring emergency surgery. More importantly, the 5-year survival rate in these patients was equal to elective cases. This should be regarded as promising and therefore considered for these patients.  相似文献   
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The prevalence of obesity is increasing worldwide. Its primary treatment consists of lifestyle changes. In severely obese (BMI > 40 kg/m2 or ≥ 35 kg/m2 with comorbidity) patients though, bariatric surgery has been found to be the only way to achieve permanent weight loss. Operations such as the placement of a gastric band or a gastric bypass can, however, lead to complications and necessitate secondary interventions. In search of less invasive treatments, placement of the EndoBarrier duodenal jejunal bypass liner appears to be a promising, safe and effective method for facilitating weight loss. The EndoBarrier is a plastic flexible tube which is gastroscopically placed in the duodenal bulb, directly behind the pylorus. It extends from the duodenum to the proximal jejunum. Recent studies have demonstrated significant weight reduction in comparison to control-diet patients. Concomitant positive effects on cardiovascular risk factors including diabetes type 2 were observed. A multicentre trial is currently being executed in order to unravel the mechanism behind these effects.  相似文献   
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