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21.
CT demonstration of prominent right hilar soft tissue collections   总被引:2,自引:0,他引:2  
Three cases of normal soft tissue collections of the right hilum which could be confused with thrombus of the right pulmonary artery or adenopathy are demonstrated. These abnormalities are due to normal accumulations of hilar fat and lymph nodes. Their typical appearance allows easy recognition.  相似文献   
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Paragangliomas occurring in the liver are rare. We report a patient with a history of nonfunctional paragangliomas in the head and neck who developed liver metastases years later. We discuss findings on cross-sectional imaging modalities, including magnetic resonance imaging (MRI), which demonstrate the hypervascular nature of the liver masses.  相似文献   
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The presence of calcification can be found in greater than 50% of thyroid cancers. With medullary thyroid carcinoma, calcifications may be found in the primary lesion as well as in metastatic lymph nodes and in the liver. We report two cases of medullary thyroid carcinoma with associated calcified liver metastases.  相似文献   
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The authors present a new method for assessing pelvic prolapse with dynamic fast magnetic resonance (MR) imaging. Twenty-six women with signs and symptoms suggesting pelvic prolapse and 16 control subjects were studied with a series of fast (6-12-second) MR images. Sagittal and coronal images were obtained with graded increase in voluntary pelvic strain, allowing for dynamic display and quantification of the pelvic prolapse process. The distance from the pubococcygeal line was used as an internal reference for measurement of descent in the maximal strain position. With use of control results for normal limit values, prolapse involving the anterior pelvic compartment (cystocele), the middle compartment (vaginal prolapse, uterine prolapse, and enterocele), and the posterior compartment (rectocele) was easily demonstrated. Significant differences between control subjects and patients with prolapse were seen at maximal strain but not in the relaxed state. Quantification of the pelvic descent process with use of fast MR imaging may be of value in surgical planning and postsurgical follow-up.  相似文献   
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As a result of the NIH investment in biomedical research, over the past 30 years we have seen many great advances impacting the health of our nation which have been fostered by the effective translation of scientific advances. However, rising costs for both research and health care mean that the NIH must make strategic decisions that maximize the return on its investment. Because treating end-stage disease is so costly, both personally and financially, learning how to pre-empt illness through molecular knowledge and behavioral interventions is the only viable strategy for maintaining the nation's health in the coming years. In order to speed scientific discovery and its efficient translation to patient care, the NIH developed the Roadmap for Biomedical Research. The Roadmap provides an incubator space for funding innovative programs to address a panoply of scientific challenges and has engendered a new culture of cooperation among researchers seeking new avenues for collaboration. An important feature of the Roadmap is the Clinical and Translational Science Awards (CTSA). The program's goals are to eliminate growing barriers between clinical and basic research, to address the increasing complexities involved in conducting clinical research, and to help institutions nationwide create an academic home for clinical and translational science. By adopting a strong strategic vision now, the NIH will be able to stand at the ready as future challenges and opportunities emerge. In keeping with our mission, the NIH's current and future actions will be defined by the requirements of the scientific community and the public health needs of the nation.  相似文献   
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Cortical somatosensory evoked potentials (CSEP) allow monitoring of spinal cord function during surgery. Ketamine has been shown to enhance CSEP amplitude, but there is no previous study comparing its effects with those of other anaesthetic regimens. Therefore, we have compared the effects of ketamine with those of fentanyl, both combined with midazolam, on CSEP monitoring during major spine surgery. Twenty patients with normal preoperative CSEP were allocated randomly to a ketamine or fentanyl group. Anaesthesia was induced with ketamine 3 mg kg-1 or fentanyl 6 micrograms kg-1 i.v., and midazolam 0.3 mg kg-1 i.v in both groups, and maintained with continuous i.v infusion of ketamine 2 mg kg-1 h-1 or fentanyl 3 micrograms kg-1 h-1, combined in both groups with midazolam 0.15 mg kg-1 h-1 and 60% nitrous oxide in oxygen. CSEP were elicited by tibial posterior nerve stimulation and measured P1 and N1 latencies, and P1-N1 amplitude, CSEP were recorded before and after induction, at 15 min, 1 and 2 h after induction, during skin closure and after removal of nitrous oxide. Both groups were comparable in characteristics, duration of surgery, mean arterial pressure and temperature. CSEP latencies were not significantly affected in either group. CSEP amplitude decreased significantly over time in the fentanyl group (from mean 2.02 (SEM 0.41) to 0.95 (0.17) microV, P < 0.05), but not in the ketamine group (from 1.33 (0.36) to 1.05 (0.31) microV, ns). Nevertheless, we did not observe any significant differences in amplitudes or latencies between the two groups. The delay in obtaining the first voluntary postoperative motor response was significantly greater in the ketamine group (170 (54) vs 55 (17) min, P < 0.01). Both ketamine and fentanyl allowed us to obtain reliable CSEP during major spine surgery, and there were no significant difference between these two anaesthetic regimens for CSEP monitoring, but a longer delay for voluntary postoperative motor assessment was observed in the ketamine group.   相似文献   
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Patients with adenocarcinoma of the prostate confined to the gland (stage B) are candidates for a potentially curative surgical procedure (radical retropubic prostatectomy). However, patients with adenocarcinoma that penetrates the capsule or invades the seminal vesicles (stage C) are no longer considered good candidates for surgical cure of their disease. The purpose of this study was to compare the ability of four radiologists to detect stage C disease on MR images and to evaluate interobserver variability. One hundred consecutive MR studies of the prostate were reviewed independently by four radiologists to determine whether the cancer was stage C (capsule penetration or seminal vesicle invasion by tumor). A radical prostatectomy was performed in each case, and careful histologic assessment was made of the prostatic capsule and seminal vesicles for any evidence of stage C disease. The sensitivity, specificity, and accuracy (true-positive + true-negative/100 patients) in detecting stage C disease were calculated for each of the four readers. Four receiver-operating-characteristic curves were generated and compared by means of the univariate z score. Percentage agreement was calculated for five specific areas of the prostate on MR images, and observations made by the best reader were compared with the other three to help determine interreader variability. The results showed that the sensitivity and specificity of MR imaging in detecting stage C disease ranged from .24 to .61 (mean, .48) and .49 to .79 (mean, .66), respectively. The accuracy of MR imaging ranged from .47 to .61 (mean, .55). The univariate z score test showed that one of the readers significantly differed from the other three. The average percentage agreement between that reader and the other three was 70% for the five separate anatomic regions. This study shows that considerable interobserver variation exists in the interpretation of MR images for staging cancer of the prostate. The average accuracy among four radiologists in determining the presence of stage C adenocarcinoma of the prostate from MR images was only slightly above a chance guess at .55.  相似文献   
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