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121.
Tissue Deformation Index as a Reliable Measure of Lateral Abdominal Muscle Activation on M‐Mode Sonography 下载免费PDF全文
Maciej Biały PhD Wacław Adamczyk MSc Rafael Gnat DSc Tomasz Stranc MSc 《Journal of ultrasound in medicine》2017,36(7):1461-1467
The aim of this article is to present a novel method of evaluating the activity of lateral abdominal muscles using M‐mode sonography. The method leads to calculation of the tissue deformation index, representing the percent change in lateral abdominal muscle thickness over time. The objectives of this study were as follows: (1) to establish the mean tissue deformation index values for individual lateral abdominal muscles; and (2) to establish the reliability of the tissue deformation index. In a group of 34 healthy young volunteers (mean age, 24.03 years; body mass, 68.89 kg; body height, 174.25 cm), the reflex response of the lateral abdominal muscles to postural perturbation in the form of rapid arm abduction was recorded in 2 series, with 6 repetitions each, and the tissue deformation index was calculated. The mean tissue deformation index values formed a gradient, increasing from deep to superficial lateral abdominal muscles: 0.06%/ms for transversus abdominis, 0.11%/ms for oblique internal, and 0.16 for oblique external muscles. The tissue deformation index values differed significantly among individual lateral abdominal muscles (all paired comparisons, P < .001). Three repeated measurements are sufficient to achieve good intra‐rater reliability of the tissue deformation index (intraclass correlation coefficient, > 0.8). 相似文献
122.
123.
Transvaginal color Doppler sonography versus sonohysterography in the diagnosis of endometrial polyps. 总被引:7,自引:0,他引:7
Juan Luis Alcázar María José Galan José Angel Mínguez Manuel García-Manero 《Journal of ultrasound in medicine》2004,23(6):743-748
OBJECTIVE: To compare the diagnostic performance of transvaginal color Doppler sonography (TVCD) and sonohysterography (SHG) in the diagnosis of endometrial polyps. METHODS: Fifty-one women (mean age, 51 years; range, 27-75 years) with clinical or B-mode sonographic suspicion of endometrial polyps were included in this prospective study. Transvaginal color Doppler sonography first and then SHG were performed in all patients. On TVCD, a polyp was suspected when a vascular pedicle penetrating the endometrium from the myometrium was identified. On SHG, a polyp was suspected when a focal polypoid lesion was seen within the endometrial cavity. All patients underwent hysteroscopy and endometrial biopsy, the findings of which were used as the criterion standard. Sensitivity and specificity for TVCD and SHG were calculated and compared by the McNemar test. RESULTS: Hysteroscopy and endometrial biopsy findings were as follows: endometrial polyps, 41; endometrial hyperplasia, 3; cystic atrophy, 4; proliferative endometrium, 2; and endometritis, 1. Sensitivity and specificity for TVCD and SHG were 95% and 80% and 100% and 80%, respectively (McNemar test, P = .5) CONCLUSIONS: Transvaginal color Doppler sonography and SHG had similar performance for diagnosing endometrial polyps. 相似文献
124.
Middle cerebral artery peak systolic and ductus venosus velocity waveforms in the hydropic fetus. 总被引:2,自引:0,他引:2
Erich Cosmi Salvatore Dessole Luisa Uras Giampiero Capobianco Donato D'Antona Alessandra Andrisani Pietro Litta Guido Ambrosini 《Journal of ultrasound in medicine》2005,24(2):209-213
OBJECTIVE: The purpose of this study was to assess whether Doppler assessment of the middle cerebral artery (MCA) peak systolic velocity (PSV) and ductus venosus (DV) velocity waveforms during sonography of hydropic fetuses may specify the cause of fetal hydrops. METHODS: A level II sonographic examination was performed in 16 hydropic fetuses, and the MCA PSV and DV velocity waveforms were assessed. The MCA PSV values divided hydropic fetuses into anemic (group 1) and nonanemic (group 2) fetuses. In group 2 fetuses, the DV was defined as normal or abnormal. Sonographic examination and Doppler assessment of these vessels specified the cause of hydrops and indicated the use of specific investigations for diagnosing the etiology of fetal hydrops. RESULTS: Seven of 16 fetuses had MCA PSV values greater than 1.50 multiples of the median (group 1). Nine of 16 fetuses had normal MCA PSV values (group 2); among them, 7 of 9 had either absent or reversed flow in the DV, and 2 had a normal DV. In group 1, the cause of fetal anemia was investigated by maternal serum tests, and 5 cordocentesis procedures were performed. In group 2, 7 of 9 fetuses had reversed flow in the DV, which suggested a cardiac abnormality confirmed by echocardiography. Five cordocentesis procedures were performed for fetal karyotype, and in 2 fetuses, the cause of hydrops was idiopathic. CONCLUSIONS: Our data suggest that assessment of the MCA PSV and DV velocity waveforms in the hydropic fetus may further our knowledge of the etiology of hydrops and may indicate which investigations among the many available should be used for diagnosing the cause of fetal hydrops. 相似文献
125.
Venetia G. Vassiliades Todd D. Ostrow Judith L. Chezmar Gary L. Hertzler Rendon C. Nelson M.D. 《Abdominal imaging》1993,18(1):61-65
Forty-three patients who were scheduled to undergo a percutaneous liver biopsy were evaluated with Doppler sonography to determine the hepatic arterial resistive index (RI). The histologic specimens were graded by a pathologist regarding cirrhosis and inflammation. The specimens demonstrated no cirrhosis in 12 of 43 (28%) patients, early cirrhosis in 10 of 43 (23%), and established cirrhosis in 21 of 43 (49%). Analysis also revealed that inflammation was absent in three of 43 (7%) patients, minimal in seven of 43 (16%), mild in 17 of 43 (40%), moderate in 13 of 43 (30%), and severe in three of 43 (7%). Hepatic artery RIs (without correction for heart rate) ranged from 0.64+0.06 in patients with early cirrhosis to 0.68 ±0.09 in patients with severe inflammation. There was no significant correlation between the degree of cirrhosis and/or inflammation and hepatic artery RI (with or without correction for heart rate). We conclude that Doppler determination of hepatic artery RIs is not a reliable method of predicting the severity of hepatic cirrhosis and/or inflammation. 相似文献
126.
5D CNS+ Software for Automatically Imaging Axial,Sagittal, and Coronal Planes of Normal and Abnormal Second‐Trimester Fetal Brains 下载免费PDF全文
127.
目的探讨大脑中动脉慢性闭塞(CMCAO)患者大脑前动脉(ACA)脑膜支代偿(LMA)对脑梗死大小的影响,分析大脑中动脉(MCA)流速与脑梗死面积的相关性。方法回顾性连续纳入2014年6月至2016年6月延边大学附属医院神经内科35例和首都医科大学宣武医院神经内科的CMCAO患者74例,对所有患者采用经颅多普勒超声(TCD)和(或)经颅彩色多普勒超声(TCCS)诊断为一侧CMCAO而对侧MCA正常,并经DSA证实。根据DSA显示ACA有无脑膜支,分为LMA组49例及无LMA组(NLMA)60例。采用TCCS和(或)TCD测量,记录患侧与健侧MCA的收缩期峰值流速(PSV)及平均流速(MFV),并计算健侧、患侧PSV比值(PSV_(健侧)/PSV_(患侧))。根据磁共振扩散加权成像(DWI)检查结果分为脑组织正常、腔隙性脑梗死、中小面积脑梗死及大面积脑梗死4级,采用秩和检验比较LMA组与NLMA组脑梗死面积的差异,并采用Spearman秩相关分析患侧MCA的血流参数与脑梗死面积的相关性。结果 (1)两组患者的患侧与健侧MCA的PSV、MFV及PSV_(健侧)/PSV_(患侧)差异均无统计学意义(均P0.05)。(2)NLMA组中卒中者占90.0%(54例),明显高于LAM组71.4%(35例),两组间差异有统计学意义(P0.05);LMA组DWI以腔隙性脑梗死为主(51.0%,25例),NLMA组多以中小面积脑梗死为主(45.0%,27例),并且大面积脑梗死发生率(21.7%,13例)高于LMA组(4.1%,2例),两组差异有统计学意义(P0.01)。(3)NLMA组患者脑梗死面积与MCA的PSV呈中度负相关(r=-0.736,P0.01),并随PSV_(健侧)/PSV_(患侧)的升高而增加,呈高度正相关(r=0.849,P0.01)。结论 CMCAO患者ACA的LMA状态与脑梗死严重程度相关,患侧MCA血流速度的减低与脑梗死面积存在明显相关性。 相似文献
128.
经阴道彩色多普勒超声对宫腔内占位性病变的诊断价值 总被引:4,自引:0,他引:4
目的探讨经阴道彩色多普勒超声对宫腔内占位性病变的诊断价值。方法对126例宫腔占位性病变经腹超声检查不满意,而后经阴道超声检查对其进行良恶性的诊断及分型并与临床结果相对照。结果本组126例,子宫内膜息肉28例,子宫黏膜下肌瘤19例,子宫内膜癌26例,子宫内膜过度增生21例,宫腔内残留物机化32例。126例宫腔内占位性病变经手术证实51例,宫腔镜证实42例,诊断性刮宫33例,误诊2例,诊断正确率为98.41%。结论经阴道彩色多普勒方法简单、实用,不受肥胖、肠气等因素干扰,为临床提供早期正确诊断,使疾病得到早期的治疗,是较为实用的检查方法之一。 相似文献
129.
Cardiopulmonary ultrasound for critically ill adults improves diagnostic accuracy in a resource‐limited setting: the AFRICA trial 下载免费PDF全文
130.
Javier Miguelez MD Miki Moskovitch MD Howard Cuckle DPhil Marcelo Zugaib MD PhD Victor Bunduki MD PhD Ron Maymon MD 《Journal of ultrasound in medicine》2010,29(12):1741-1747
Objective. The purpose of this study was to estimate the Down syndrome detection and false‐positive rates for second‐trimester sonographic prenasal thickness (PT) measurement alone and in combination with other markers. Methods. Multivariate log Gaussian modeling was performed using numerical integration. Parameters for the PT distribution, in multiples of the normal gestation‐specific median (MoM), were derived from 105 Down syndrome and 1385 unaffected pregnancies scanned at 14 to 27 weeks. The data included a new series of 25 cases and 535 controls combined with 4 previously published series. The means were estimated by the median and the SDs by the 10th to 90th range divided by 2.563. Parameters for other markers were obtained from the literature. Results. A log Gaussian model fitted the distribution of PT values well in Down syndrome and unaffected pregnancies. The distribution parameters were as follows: Down syndrome, mean, 1.334 MoM; log10 SD, 0.0772; unaffected pregnancies, 0.995 and 0.0752, respectively. The model‐predicted detection rates for 1%, 3%, and 5% false‐positive rates for PT alone were 35%, 51%, and 60%, respectively. The addition of PT to a 4–serum marker protocol increased detection by 14% to 18% compared with serum alone. The simultaneous sonographic measurement of PT and nasal bone length increased detection by 19% to 26%, and with a third sonographic marker, nuchal skin fold, performance was comparable with first‐trimester protocols. Conclusions. Second‐trimester screening with sonographic PT and serum markers is predicted to have a high detection rate, and further sonographic markers could perform comparably with first‐trimester screening protocols. 相似文献