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101.
Rectal compliance in females with obstructed defecation   总被引:8,自引:3,他引:8  
PURPOSE: This study was designed to investigate whether rectal compliance is altered in females with obstructed defecation. METHODS: Eighty female patients with obstructed defecation and 60 control subjects were studied. Rectal compliance was measured with an infinitely compliant polyethylene bag. This bag was inserted in the rectum and inflated with air to selected pressure plateaus (range, 0–60 mmHg; cumulative steps of 2 mmHg with a duration of ten seconds) using a computer-controlled electromechanical barostat system. Volume changes at the levels of distending pressures were recorded. The distending pressures, needed to evoke first sensation of content in the rectum, earliest urge to defecate, and the maximum tolerable volume were noted. RESULTS: In all cases, the compliance curve had a characteristic triphasic (S-shaped) form. The mean compliance curve obtained from the patients was identical to that of the controls. However, the course of the compliance curve fell above the normal range (mean + 2 SD) in 14 patients. In ten (71 percent) of these patients, a large rectocele was seen at evacuation proctography. Such a rectocele was observed in only five patients (7.6 percent) with a normal compliance curve (P<0.001). Eighty percent of the controls experienced earliest urge to defecate during the second phase of the curve. In 75 percent of the patients, this occurred in the third phase. The mean pressure threshold for first sensation, earliest urge to defecate, and maximum tolerable volume were significantly higher in patients compared with control subjects. Ten of the patients experienced no sensation at all in the pressure range between 0 and 60 mmHg. CONCLUSION: In females with obstructed defection, the compliance of the rectal wall is normal.  相似文献   
102.
目的探讨脑卒中后肩关节半脱位对偏瘫侧上肢周围神经电生理参数的影响。方法纳入20例脑卒中伴肩关节半脱位的患者,分别对患者双上肢肩胛上神经、腋神经、肌皮神经、桡神经、正中神经、尺神经的运动神经传导及桡神经、正中神经、尺神经的感觉神经传导进行评估,并对偏瘫上肢冈上肌、三角肌、肱二头肌、伸指总肌、拇短展肌和小指展肌进行静息状态下针极肌电图检测;采用Brunnstrom分期对患者的上肢和手功能进行评估,并对患侧神经肌肉复合动作电位(CMAP)波幅的变化率与患者病程、年龄及上肢Brunnstrom分期进行相关性分析。结果与健侧相比,脑卒中后肩关节半脱位侧的肩胛上神经、腋神经、肌皮神经、桡神经、正中神经、尺神经CMAP波幅均显著降低(P<0.01),肩胛上神经和腋神经的潜伏期延长(P<0.05),肌皮神经、桡神经、正中神经和尺神经潜伏期双侧差异无统计学意义(P>0.05)。桡神经、正中神经和尺神经运动传导速度双侧无差异(P>0.05)。偏瘫侧腋神经、肩胛上神经、肌皮神经CMAP波幅变化率明显高于桡神经、正中神经和尺神经(P<0.05)。偏瘫侧桡神经、正中神经和尺神经的感觉神经动作电位(SNAP)较健侧降低(P<0.01),感觉传导速度双侧差异无统计学意义(P>0.05)。偏瘫侧SNAP波幅变化率由高到低依次为正中神经、桡神经和尺神经,但两两对比差异均无统计学意义(P>0.05),感觉神经传导速度变化率两两对比差异亦无统计学意义(P>0.05)。肩关节半脱位后上肢所检肌肉均存在不同程度的自发电位,偏瘫上肢近端出现率高于远端肢体,其中冈上肌自发电位出现率为61.54%,三角肌为84.62%,肱二头肌为69.23%,伸指总肌和拇短展肌为46.15%,小指展肌为30.77%。偏瘫侧CMAP变化率与患者病程、年龄及上肢Brunnstrom分期之间均无明显相关性(P>0.05)。结论脑卒中后肩关节半脱位可导致支配肩和上臂的周围神经损害程度大于支配前臂和手的神经,可能影响患者上肢功能的恢复。  相似文献   
103.
Background: Sensory stimuli are conducted by several cutaneous sensory nerves and tactile corpuscles. The latter are specialized sensory organs that represent the starting point of many afferent sensory pathways. To date, our knowledge about the distribution of the sensory innervation in the umbilical skin of females is incomplete.

Aim of the study: To elucidate the morphology of the cutaneous innervation of the normal female umbilical skin.

Materials and methods: Biopsies of normal umbilical skin were obtained from female patients undergoing umbilical hernial repair. The specimens were processed for both immunohistological (antibodies against PGP9.5, pan-neuronal marker, and S-100 protein, marker of Schwann cells) and ultrastructural (transmission electron microscopy) examinations.

Results: The authors found abundant genital end-bulb-like structures, numerous epidermal and dermal Merkel cells, Meissner and Ruffini corpuscles, intraepidermal nerve terminals, and multiple free nerve endings surrounding the ducts and acini of the sweat glands.

Conclusions: The umbilical skin of females has abundant sensory innervation similar to that of the glans penis.  相似文献   
104.
Chronic cannabis use has been associated with neurocognitive deficits, alterations in brain structure and function, and with psychosis. This study investigated the effects of chronic cannabis use on P50 sensory-gating in regular users, and explored the association between sensory gating, cannabis use history and the development of psychotic-like symptoms. Twenty controls and 21 regular cannabis users completed a P50 paired-click (S1 and S2) paradigm with an inter-pair interval of 9 s. The groups were compared on P50 amplitude to S1 and S2, P50 ratio (S2/S1) and P50 difference score (S1–S2). While cannabis users overall did not differ from controls on P50 measures, prolonged duration of regular use was associated with greater impairment in sensory gating as indexed by both P50 ratio and difference scores (including after controlling for tobacco use). Long-term cannabis users were found to have worse sensory gating ratios and difference scores compared to short-term users and controls. P50 metrics did not correlate significantly with any measure of psychotic-like symptoms in cannabis users. These results suggest that prolonged exposure to cannabis results in impaired P50 sensory-gating in long-term cannabis users. While it is possible that these deficits may have pre-dated cannabis use and reflect a vulnerability to cannabis use, their association with increasing years of cannabis use suggests that this is not the case. Impaired P50 sensory-gating ratios have also been reported in patients with schizophrenia and may indicate a similar underlying pathology.  相似文献   
105.
BackgroundSensory disorders frequently accompany the motor disorders in children with cerebral palsy (CP).Research questionDo children with CP have sensory disturbances in their lower extremities? If there are sensory impairments, do these impairments affect gait?MethodsIn total, 45 children (18 females, 27 males) in an age range between 5 and 18 years were included in the study: 15 typically developing children, 15 unilaterally affected children with cerebral palsy, and 15 bilaterally affected children with cerebral palsy. They could walk independently at the levels of I or II according to the gross motor function classification. After the demographic data of the children were recorded, their tactile sense, vibration sense, two-point discrimination, and proprioception were evaluated, and the Edinburgh Visual Gait Score (EVGS) was used for gait assessment.ResultsFailures were discovered in lower extremity tactile (p = 0.001), two-point discrimination (p = 0.001), and proprioceptive senses of the children with CP (p = 0.001), and the loss of tactile sense was found to be related to gait disorders (p = 0.02, r = 0.41).SignificanceThere were deficiencies in the lower extremity senses, and deficiencies in the tactile sense negatively affected gait. Performing sensory assessments, which are considered to be fundamental for gait training in the rehabilitation of children with CP, and providing support for the lacking parameters in the intervention programs may create positive effects on gait.  相似文献   
106.
BackgroundIntegration of visual, vestibular, and proprioceptive sensations contributes to postural control. People with peripheral visual field loss have serious postural instability. However, the directional specificity of postural stability and sensory reweighting caused by gradual peripheral visual field loss remain unclear.Research questionWhat are the effects of peripheral visual field loss on static postural control?MethodsFifteen healthy young adults participated in this study. The participants were asked to stand quietly on a foam surface. Three conditions of virtual visual field loss (90°, 45°, and 15°) were provided by a head-mounted display, and ground reaction forces were collected using a force plate to calculate the displacements of the center of pressure (COP).ResultsThe root mean square (RMS), mean velocity, and 95% ellipse area of COP displacements in the horizontal plane increased, and RMS in the anteroposterior (AP) direction was unchanged under the smallest visual field condition compared to the largest one. The power spectrum density of COP displacements in the low-frequency band was decreased and that in the medium-frequency band was increased in the AP direction.SignificanceDuring quiet standing of young healthy adults with peripheral visual field loss, increased peripheral visual field loss resulted in lower postural stability. Postural stability in the AP direction was maintained contrary to the functional sensitivity hypothesis. Peripheral visual field loss reduced the weighting of the visual input and increased that of the vestibular input in the AP direction to maintain equilibrium.  相似文献   
107.
Chemotherapy-induced peripheral neuropathy (CIPN) is one of the most frequently reported adverse effects of cancer treatment. CIPN often persists long after treatment completion and has detrimental effects on patient’s quality of life. There are no efficacious FDA-approved drugs for CIPN. We recently demonstrated that nasal administration of mesenchymal stem cells (MSC) reverses the cognitive deficits induced by cisplatin in mice.Here we show that nasal administration of MSC after cisplatin- or paclitaxel treatment- completely reverses signs of established CIPN, including mechanical allodynia, spontaneous pain, and loss of intraepidermal nerve fibers (IENF) in the paw. The resolution of CIPN is associated with normalization of the cisplatin-induced decrease in mitochondrial bioenergetics in DRG neurons. Nasally administered MSC enter rapidly the meninges of the brain, spinal cord and peripheral lymph nodes to promote IL-10 production by macrophages.MSC-mediated resolution of mechanical allodynia, recovery of IENFs and restoration of DRG mitochondrial function critically depends on IL-10 production. MSC from IL-10 knockout animals are not capable of reversing the symptoms of CIPN. Moreover, WT MSC do not reverse CIPN in mice lacking IL-10 receptors on peripheral sensory neurons. In conclusion, only two nasal administrations of MSC fully reverse CIPN and the associated mitochondrial abnormalities via an IL-10 dependent pathway. Since MSC are already applied clinically, we propose that nasal MSC treatment could become a powerful treatment for the large group of patients suffering from neurotoxicities of cancer treatment.  相似文献   
108.
IntroductionAlthough sensory tricks are well known as the maneuvers that temporarily relieve dystonic symptoms in patients with cervical dystonia (CD), the underlying neurophysiological mechanisms remain unclear. We aimed to investigate brain potentials related to sensory tricks in patients with CD.MethodsThirteen patients with CD and 13 age-matched healthy volunteers participated. The experiment consisted of three conditions (moving the neck, moving an arm, and performing sensory tricks) presented in different blocks in random order in a contingent negative variation (CNV) paradigm. Warning and trigger stimuli (S1 and S2) were presented to the participants, who were instructed to prepare to perform the specific task for each condition after S1, and then to perform the task after S2. Early and late components of the CNV were measured.ResultsThe late CNVs in patients with CD were significantly larger than those in healthy participants in Fz, FCz, Cz, and C3 electrodes. Only in patients with CD, the late CNVs were significantly greater for the ‘sensory tricks’ condition compared to the ‘move neck’ condition in Fz and C3 electrodes.ConclusionThe late CNV is increased during sensory tricks in patients with CD, suggesting that sensory tricks may affect mechanisms related to the motor preparatory phase in the premotor and primary motor areas. Sensory tricks may normalize impaired motor preparation in dystonia, leading to improved dystonic symptoms.  相似文献   
109.
目的探讨军校学员的学习风格。方法通过Myers-Briggs心理量表和感官偏爱测试表,调查某军校2010-2012年选修《时间管理与学习技巧》课程的所有学员的个性类型和感官偏爱等。结果军校学员的个性类型以内向为主,并呈逐年下降的趋势(χ2=7.320,P=0.026);2010年学员的感官偏爱主要是运动知觉,其次是听觉、阅读/写作、视觉,差别有统计学意义(χ2=12.400,P=0.006)。结论军校学员的个性类型以ISFJ(内向-直觉-情感-判断)为主,感官偏爱以运动知觉为主。掌握学员的学习风格,是科学有效的进行教学和学习的基础。  相似文献   
110.
《Gait & posture》2015,41(4):581-586
Complexity is a new measure for identifying the adaptability of a complex system to meet possible challenges. For a center of pressure (COP) time series, the complexity measure represents the stability of postural control. In this study, multiscale entropy (MSE) was used to evaluate the complexity of COP time series in six test conditions of sensory organization test (SOT). Complexity index (CI) is defined as the summation of entropies with coarse-graining scales 1–20 by MSE. A total of 51 subjects belonging to 3 groups – healthy-young, healthy-elderly and dizzy – were recruited in this study. The COP signals in both anteroposterior (AP) and mediolateral (ML) directions were analyzed respectively. According to our results, the CI of AP-direction COP time series is significantly correlated to the equilibrium score, which represents the stability of postural control in SOT. The AP-direction sway is significant larger than the ML-direction sway, particularly in the test conditions with sway-surface. In additions, the CI of AP-direction COP for the healthy-elderly and dizzy groups are significantly lower than those for the healthy young group in the test conditions 1–4. The CI of ML-direction COP for the healthy-elderly group is significantly lower than those for the healthy-young and dizzy groups under test conditions 3 and 6. These results show that the complexity loss is a common status of AP-direction COP time series for both healthy-elderly and dizzy groups, and the complexity of ML-direction COP time series for subjects with unilateral vestibular dysfunction is higher than that for the healthy-elderly group specifically under test conditions 3 and 6.  相似文献   
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