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101.
102.
In the framework of a series of investigations concerning the neural substrate of aversion, electrophysiological methods were used in order (1) to specify, within the rat's periaqueductal gray (PAG), functional properties, viz. conduction velocity and refractory period, of PAG neurons already assessed in previous studies by means of behavioral methods, and (2) to gather data on their local synaptic relationships. Unit activities were recorded from the periaqueductal gray with the aim of analyzing those alterations that would be induced by locally applying an electrical stimulation with parameters shown to elicit escape behavior. An implanted row of electrodes allowed the application of a stimulation to several sites aligned along a mediolateral or a rostrocaudal axis through the periaqueductal gray. The results indicate that an electrical stimulation applied to the periaqueductal gray may induce its effects through the activation of a number of dendrites and many slow conducting fibers running in a great variety of directions and branching within the periaqueductal gray. Their refractory period was surprisingly low (0.6 ms) for slow conducting fibers (below 1 m/s). The local circuitry appears to include many inhibitory connections. Their organization is assumed to be partly recurrent. Stimulation-induced inhibition becomes predominant when the stimulation is moved away from the recorded neuron along the mediolateral axis, but not along the rostrocaudal axis.  相似文献   
103.
104.
Ipecac, an over-the-counter emetic agent, has been a drug of choice for abuse by patients with eating disorders. Its alkaloid emetine has been associated with serious cardiac toxicity; however, the dose effect has not been well established. We present a patient with anorexia and bulimia nervosa who ingested ipecac chronically and developed the characteristic manifestations of ipecac toxicity. Unexpectedly, her induced left ventricular dysfunction returned to normal after only 10 days of withholding the drug. This finding, in contrast with the findings of other reports, establishes that ipecac cardiomyopathy can be readily reversible. The cumulative experience thus far, nonetheless, provides no discernible pattern of the effect of ipecac on the myocardium. Thus, in the continuum of poisoning, the point at which the myocardium becomes irreversibly damaged is undetermined. With continued abuse, potentially lethal outcome, and limited experience with ipecac cardiotoxicity, further investigation and perhaps heightened restriction of the drug are warranted.  相似文献   
105.
Solitary epithelioid histiocytoma (previously called reticulohistiocytoma) is a rare benign dermal histiocytic proliferation characterized by the presence of large, eosinophilic histiocytes with 'glassy' cytoplasm. This entity assumes importance because of its close histologic resemblance to several benign as well as malignant cutaneous lesions. Involvement of the penis is extremely rare, and to our knowledge, only one case has been previously described in the literature. We report a case of solitary epithelioid histiocytoma in a 34-year-old man who presented with a nodule in the glans penis. Microscopy showed proliferation of large epithelioid histiocytes with abundant eosinophilic cytoplasm, which expressed CD68, CD163 and vimentin. This case highlights the significance of recognizing this unusual lesion and differentiating it from its histologic mimics.  相似文献   
106.
107.
The diagnosis of endometriosis may delay for many years due to non-deterministic symptoms and avoiding surgical interventions. Kisspeptins are hormones that interact with endometrial tissue to limit invasions during placentation and various cancers and are suggested to be also associated with endometriosis. This study evaluated if serum kisspeptin levels are associated with the invasion depth in endometriosis. Forty patients between 18 and 45 years of age and admitted to a tertiary-care Obstetrics and Gynecology Department between 2020 and 2021 with a diagnosis of endometriosis, and 40 patients without endometrioma were included in the study. Demographic, obstetric, clinical, and biochemical characteristics were evaluated in patients with superficial (SE) and deep infiltrating (DIE) endometriosis and healthy controls. Twenty patients (50%) had SE, 14 (35%) had DIE, and 22 (55%) had endometrioma in the patient group. Fertility rates were higher among controls, but similar between patients with SE and DIE. CA125 levels were significantly higher in the DIE group. SE and DIE groups had similar kisspeptin values, significantly higher than controls. CA125 and kisspeptin levels were not correlated in study groups. Serum kisspeptin levels were significantly different between endometriosis patients and healthy controls. However, kisspeptin levels were unable to differentiate endometriosis severity. Our results suggest that kisspeptins might play a role in the pathogenesis of endometriosis, which needs further assessment in more comprehensive studies.  相似文献   
108.
A discrimination situation was used to study the effects of morphine microinjected into the periaqueductal gray (PAG) on the aversive effects induced by PAG or medial hypothalamic (MH) electrical stimulation. Rats were trained in a T-maze to interrupt a high intensity (HI) stimulation inducing a short escape latency by pressing the lever (HI lever) located in one arm of the maze and a low intensity (LI) stimulation inducing a longer escape latency by pressing the lever (LI lever) located in the other arm. Microinjections of 15 nmol (5 micrograms) or 40 nmol (13 micrograms) of morphine both lengthened the escape latencies and shifted towards the LI lever the animal's choice in order to interrupt HI stimulations. This effect of morphine showed a similar time course as regards both escape latency and lever choice; it was more marked on PAG than on MH stimulation-induced aversive effects. The data are discussed in terms of morphine microinjections into PAG lengthening the escape latency by decreasing the aversiveness of PAG or MH stimulation rather than by affecting the animals' ability to respond to such stimulations.  相似文献   
109.
开窗畸形之基底动脉并发颅内多发性动脉瘤   总被引:1,自引:1,他引:0  
血管开窗畸形 ,也即血管局部节段性扩张 ,是一种罕见的先天性动脉变异。据一组尸体解剖的文献报道基底动脉的开窗畸形发生率为 1.3 %~ 5 .3 % [1] ;基底动脉开窗畸形的血管造影发生率为 0 .4%~ 0 .6% [2 ] 。基底动脉开窗畸形并发颅内动脉瘤非常罕见 ,首例报道是 1979年[3 ] 。虽然为一罕见病例 ,此病例在血管造影 ,外科手术或尸检中的表现仍有较多作者报道[3~ 7] ,尤以日本的文献报道最多[7] 。Campos等[5] 报道基底动脉近端开窗畸形并发动脉瘤的病例最多 ,为 2 1例。尽管如此 ,基底动脉开窗畸形并发颅内多发性动脉瘤仍属罕见 ,本文就…  相似文献   
110.
Sympathetic skin response in premenstrual syndrome   总被引:1,自引:0,他引:1  
Abstract Premenstrual syndrome is a term which includes a broad group of emotional, behavioral and physical symptoms that occur for several days before menses and subside following the menstrual period. Many women experience premenstrual syndrome symptoms, particularly physical ones such as breast tenderness and swelling. Approximately 5–10% women suffer from severe premenstrual syndrome and another 30–40% have moderate symptoms. Premenstrual syndrome continues to be an unsolved problem.In this study, we evaluated 24 premenstrual syndrome patients and 20 healthy women in the control group. The ages of the women were 22–34 years (mean ± SD: 25±3) for the premenstrual syndrome group and 23–34 (25±3) for the control group. The sympathetic skin response was recorded from the palms, soles and genital regions by using electrical stimuli to the median nerve at the wrist.The sympathetic skin response was recorded twice, in the follicular and late luteal phases of menstruation.The follicular and late luteal phase sympathetic skin response of the two groups were compared. The amplitudes and latency values of the late luteal and follicular phase sympathetic skin response from the premenstrual syndrome group and control group women were statistically similar. We also did not find any latency or amplitude difference in the sympathetic skin response obtained from the three regions of the premenstrual syndrome patients and the control group.We checked sympathetic skin response in the symptomatic (late luteal phase) and asymptomatic (follicular phase) periods of patients with premenstrual syndrome, a disorder known to have many autonomic symptoms, to determine whether there was sudomotor sympathetic involvement.The results of our PMS patients indicate at the very least that there is no difference with the control subjects as regards peripheral sudomotor functions.  相似文献   
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