全文获取类型
收费全文 | 60104篇 |
免费 | 5070篇 |
国内免费 | 2537篇 |
专业分类
耳鼻咽喉 | 564篇 |
儿科学 | 835篇 |
妇产科学 | 480篇 |
基础医学 | 6681篇 |
口腔科学 | 992篇 |
临床医学 | 6581篇 |
内科学 | 7839篇 |
皮肤病学 | 1248篇 |
神经病学 | 2914篇 |
特种医学 | 2512篇 |
外国民族医学 | 5篇 |
外科学 | 6295篇 |
综合类 | 10206篇 |
现状与发展 | 11篇 |
一般理论 | 9篇 |
预防医学 | 4945篇 |
眼科学 | 1115篇 |
药学 | 7005篇 |
44篇 | |
中国医学 | 3785篇 |
肿瘤学 | 3645篇 |
出版年
2024年 | 147篇 |
2023年 | 672篇 |
2022年 | 1485篇 |
2021年 | 2417篇 |
2020年 | 1723篇 |
2019年 | 1386篇 |
2018年 | 1576篇 |
2017年 | 1577篇 |
2016年 | 1612篇 |
2015年 | 2508篇 |
2014年 | 3196篇 |
2013年 | 3772篇 |
2012年 | 5261篇 |
2011年 | 5606篇 |
2010年 | 4371篇 |
2009年 | 3732篇 |
2008年 | 4357篇 |
2007年 | 4078篇 |
2006年 | 3672篇 |
2005年 | 3100篇 |
2004年 | 2300篇 |
2003年 | 1897篇 |
2002年 | 1493篇 |
2001年 | 1332篇 |
2000年 | 1162篇 |
1999年 | 730篇 |
1998年 | 302篇 |
1997年 | 254篇 |
1996年 | 197篇 |
1995年 | 188篇 |
1994年 | 163篇 |
1993年 | 114篇 |
1992年 | 167篇 |
1991年 | 183篇 |
1990年 | 148篇 |
1989年 | 112篇 |
1988年 | 99篇 |
1987年 | 92篇 |
1986年 | 81篇 |
1985年 | 56篇 |
1984年 | 38篇 |
1983年 | 51篇 |
1982年 | 36篇 |
1981年 | 21篇 |
1980年 | 21篇 |
1979年 | 32篇 |
1978年 | 18篇 |
1977年 | 17篇 |
1976年 | 13篇 |
1974年 | 17篇 |
排序方式: 共有10000条查询结果,搜索用时 171 毫秒
61.
不同频率电刺激对神经痛的干预作用 总被引:2,自引:0,他引:2
神经痛是由周围神经病变引起并放射至该神经支配范围内的疼痛,其临床症状重,持续时间长,治疗困难。本文总结近年来应用疏波、密波与疏密波电针和经皮电刺激于神经痛治疗的临床研究,结合相关实验对电针频率与补泻的关系研究,探索针灸治疗神经痛的可能应用前景。 相似文献
62.
Paclitaxel with Cisplatin as Salvage Treatment for Patients with Previously Treated Advanced Transitional Cell Carcinoma of the Urothelial Tract 下载免费PDF全文
63.
Abstract: Juvenile xanthogranuloma is a benign histiocytic skin disorder encountered primarily in infancy and childhood. Approximately 0.4% of cases exhibit ocular manifestations, which can result in glaucoma and blindness. We present a case of a 7-month-old male with unilateral glaucoma associated with Juvenile xanthogranuloma, and emphasize the importance of an ocular screening in patients with Juvenile xanthogranuloma, especially those with periocular lesions. 相似文献
64.
BACKGROUND CONTEXT: Spinal manipulation (SM) is a form of manual therapy used clinically to treat patients with low back and neck pain. The most common form of this maneuver is characterized as a high-velocity (duration <150 ms), low-amplitude (segmental translation <2 mm, rotation <4 degrees , and applied force 220-889 N) impulse thrust (high-velocity, low-amplitude spinal manipulation [HVLA-SM]). Clinical skill in applying an HVLA-SM lies in the practitioner's ability to control the duration and magnitude of the load (ie, the rate of loading), the direction in which the load is applied, and the contact point at which the load is applied. Control over its mechanical delivery is presumably related to its clinical effects. Biomechanical changes evoked by an HVLA-SM are thought to have physiological consequences caused, at least in part, by changes in sensory signaling from paraspinal tissues. PURPOSE: If activation of afferent pathways does contribute to the effects of an HVLA-SM, it seems reasonable to anticipate that neural discharge might increase or decrease in a nonlinear fashion as the thrust duration approaches a threshold value. We hypothesized that the relationship between the duration of an impulsive thrust to a vertebra and paraspinal muscle spindle discharge would be nonlinear with an inflection near the duration of an HVLA-SM delivered clinically (<150 ms). In addition, we anticipated that muscle spindle discharge would be more sensitive to larger amplitude thrusts. STUDY DESIGN/SETTING: A neurophysiological study of spinal manipulation using the lumbar spine of a feline model. METHODS: Impulse thrusts (duration: 12.5, 25, 50, 100, 200, and 400 ms; amplitude 1 or 2 mm posterior to anterior) were applied to the spinous process of the L6 vertebra of deeply anesthetized cats while recording single unit activity from dorsal root filaments of muscle spindle afferents innervating the lumbar paraspinal muscles. A feedback motor was used in displacement control mode to deliver the impulse thrusts. The motor's drive arm was securely attached to the L6 spinous process via a forceps. RESULTS: As thrust duration became shorter, the discharge of the lumbar paraspinal muscle spindles increased in a curvilinear fashion. A concave-up inflection occurred near the 100-ms duration eliciting both a higher frequency discharge compared with the longer durations and a substantially faster rate of change as thrust duration was shortened. This pattern was evident in paraspinal afferents with receptive fields both close and far from the midline. Paradoxically, spindle afferents were almost twice as sensitive to the 1-mm compared with the 2-mm amplitude thrust (6.2 vs. 3.3 spikes/s/mm/s). This latter finding may be related to the small versus large signal range properties of muscle spindles. CONCLUSIONS: The results indicate that the duration and amplitude of a spinal manipulation elicit a pattern of discharge from paraspinal muscle spindles different from slower mechanical inputs. Clinically, these parameters may be important determinants of an HVLA-SM's therapeutic benefit. 相似文献
65.
[目的]探讨一氧化氮在激素性股骨头坏死发病中的作用.[方法]制作激素性股骨头坏死家兔模型后,在不同时期测定血浆及软骨中的一氧化氮含量,观察股骨头的组织学变化.[结果]激素性股骨头坏死家兔血浆和软骨中的一氧化氮含量均明显升高,股骨头髓腔中的脂肪细胞明显增多,骨小梁变细、稀疏及断裂,空骨陷窝明显增多.电子显微镜观察见骨细胞核染色质浓缩,体积缩小,胞浆中内质网及线粒体肿胀变性,粗面内质网上的核糖体脱落.[结论]一氧化氮参与激素性股骨头坏死的发病过程. 相似文献
66.
子宫腺肌症病变中雌激素、孕激素、癌基因、凋亡抑制基因的表达研究 总被引:1,自引:1,他引:0
目的 研究雌激素(ER)、孕激素(PR)及癌基因(cerbB-2)、凋亡抑制基因(Bcl-2)在子宫腺肌症病变中的表达和子宫腺肌症发病的相关性。方法 用免疫组化方法检测40例子宫腺肌症病变组织中ER及其他生物学指标的表达。结果 ER、PR与CerbB.2、Bcl-2在子宫腺肌症病变中均有不同程度的阳性表达,子宫肌层异位内膜ER阳性表达率97.5%,PR阳性率97.5%,cerbB-2阳性率82.5%,Bcl-2阳性率62.5%。在位内膜和异位内膜ER、PR均呈阳性,阳性率比较差异无统计学意义(P〉0.05)。异位内膜cerbB-2的强阳性率高于在位内膜,差异有统计学意义(P〈0.05)。ER、PR与cerbB-2、Bcl-2阳性率相比具有相关性(P〈0.05)。结论 ER、PR与cerbB.2、Bcl-2在异位内膜高表达,提示这些生物学指标在子宫腺肌症发生发展中发挥作用。 相似文献
67.
目的通过是否进行腭咽肌肉重建的两组腭裂修复术后患者鼻咽内窥镜的比较观察,了解腭咽部肌肉重建术后腭咽闭合状况的改变。方法将41例腭裂术后患者,按照在腭裂修复时是否进行腭咽肌肉重建分为重建组(22例)和非重建组(19例),以鼻咽纤维内窥镜记录静态和发音时腭咽闭合运动状况,对两组患者腭咽闭合运动类型和状况进行比较。结果重建组静态腭咽腔形态较非重建组明显缩小,各壁光滑丰满,未见软腭鼻腔面V型缺损畸形;动态时以环状闭合为主。非重建组静态腭咽腔形态较大,可见软腭鼻腔面V型缺损畸形;动态时以冠状闭合为主。经比较重建组腭咽闭合良好率(90.91%)明显优于非重建组(37.31%)。结论鼻咽内窥镜观察证实腭咽肌肉重建腭裂修复术后腭咽闭合功能恢复明显优于非重建组。腭裂修复术时重建腭咽肌肉有助于缩小腭咽腔和更易于达到良好的腭咽闭合状态。 相似文献
68.
J-H Lee S-Y Kwon H-I Yoon C J Yoon K-W Lee S-G Kang C-T Lee 《The international journal of tuberculosis and lung disease》2007,11(7):781-787
OBJECTIVE: To evaluate the factors that influence the outcome of bronchial arterial embolisation (BAE) in chronic tuberculosis (TB). In cases of chronic TB, non-bronchial systemic arteries (NBSA) provide a significant source of massive or recurrent haemoptysis. DESIGN: Medical records and radiological findings of 30 consecutive TB patients who underwent BAE were retrospectively analysed and compared with those of 19 bronchiectasis patients. RESULTS: Chronic TB patients had higher numbers of total feeding vessels (4.40 +/- 3.85 vs. 1.79 +/- 1.51, P = 0.007) and NBSA (1.57 +/- 1.63 vs. 0.42 +/- 0.61, P = 0.005) than the bronchiectasis patients. The number of embolisations required for obliterating feeding vessels (3.87 +/- 2.48 vs. 1.95 +/- 1.47, P = 0.004), and the incidence of incomplete embolisation (30% vs. 5.3%, P = 0.033) were also higher in the TB patients. Moreover, recurrence after BAE was more frequent in the TB patients (17/30, 56.7% vs. 5/19, 26.3%, P = 0.037). Male sex, past history of haemoptysis and incomplete embolisation during BAE were associated with higher recurrence of haemoptysis in chronic TB patients. The existence of a fungus ball or significant pleural thickening (>/=10 mm) was not found to influence the recurrence rate of haemoptysis. CONCLUSION: The haemoptysis recurrence rate was higher in chronic TB than in bronchiectasis; this was found to be related to incomplete feeding vessel embolisation. 相似文献
69.
Hoon-Chul Kang Ji Won Kwon Young Mock Lee Heung Dong Kim Hong Jin Lee Si Houn Hahn 《Child's nervous system》2007,23(11):1301-1307
OBJECTIVES: This study sought to characterize epileptic phenotypes in children with nonspecific mitochondrial disease (MD) and to evaluate MD diagnostic approaches. METHODS: A retrospective analysis of the medical, electroencephalogram, and laboratory records of 142 patients with epilepsy was performed. The patients were evaluated for MD, and 124 patients were included in the final cohort. The MD criteria used included an oral glucose lactate stimulation test (OGLST) and urine organic acid/plasma amino acid (UOA/PAA) assays as metabolic indicators of modified Walker criteria, as suggested by Bernier et al. (Neurology 59:1406-1411, 2002). RESULTS: Twenty-two patients were classified as having definite MD (9), probable MD (5), possible MD (6), or pyruvate dehydrogenase (PDH) deficiency (3), including one patient which showed a respiratory chain (RC) defect and PDH deficiency. Seven out of eight patients in whom significant RC defects were observed showed complex I defects. In 14 patients, epileptic seizures start at infantile ages. Of 17 patients who substantially presented generalized seizures, 4 patients started with partial seizures. Five patients consistently presented only partial seizures. The OGLST and UOA/PAA assays were useful for a more precise diagnosis of MD, although low positive predictive value of the OGLST was regrettable. No patient was classified as definite MD by Walker's original criteria, but the use of our revised MD criteria resulted in the classification of nine additional patients as definite MD. CONCLUSIONS: MD manifested considerable diverse epileptic phenotypes and should be considered in the differential diagnosis of epilepsy in children with unexplained encephalomyopathy and progressive and fluctuating clinical courses. 相似文献
70.