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Background

Recently, with rapid changes in the Japanese lifestyle, the clinical condition of patients with multiple chemical sensitivity (MCS) may also have undergone change. Thus, we conducted a new survey for subjective symptoms, ongoing chemical exposures, the prevalence of allergic diseases, and presumed onset/trigger factors in patients with MCS and compared results with those of an old survey from ten years ago.

Methods

The new survey was conducted from 2012 to 2015 and the old survey was independently conducted from 1999 to 2003, meaning it was not a follow-up study. Patients were initially diagnosed by physicians at five medical institutions with MCS specialty outpatient services, with 111 and 103 patients participating in the new and old surveys, respectively. The controls were a general population living in Japan, with 1313 and 2382 participants in the new and old surveys, respectively. Subjective symptoms and ongoing chemical exposure were evaluated using a quick environmental exposure sensitivity inventory. Additionally, from clinical findings recorded by an attending physician, the prevalence of allergic diseases and presumed onset/trigger factors were evaluated. Differences between new and old surveys were analyzed using logistic regression analyses and significance tests.

Results

Compared with ten years ago: (1) Regarding factors affecting patients with ongoing chemical exposures, the proportion of patients affected decreased significantly for two items only (insecticides and second-hand smoke). The proportion of controls showing ongoing exposure to 8 out of 10 items changed significantly. (2) In patients, scores for chemical intolerances, other intolerances, and life impacts increased significantly. (3) In terms of the prevalence of allergic diseases among patients with MCS, bronchial asthma (adjusted odds ratio [AOR]: 5.19), atopic dermatitis (AOR: 3.77), allergic rhinitis (AOR: 5.34), and food allergies (AOR: 2.63) increased significantly, while hay fever (AOR: 0.38) and drug allergies (AOR: 0.40) decreased significantly. (4) With regard to construction and renovation, which was the presumed predominant onset/trigger factor for MCS 10 years ago, this decreased from 68.9% to 35.1%; in contrast, electromagnetic fields (0.0%–26.1%), perfume (0.0%–20.7%), and medical treatment (1.9%–7.2%) increased significantly, confirming the diversification of onset/trigger factors.

Conclusion

Compared to ten years ago, for patients with MCS, an increase in avoidance behavior toward chemical substance exposures, which were presumed to be aggravating factors for symptoms, was confirmed. It has been suggested that the ongoing chemical exposure of the general population in Japan has largely changed. In addition, for patients with MCS, chemical intolerances and life impacts have become severe, the prevalence of the main allergic diseases has increased, and onset/trigger factors have become diversified.  相似文献   
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We investigated the clinical and histopathologic features of 26 cases of mucocele of the glands of Blandin-Nuhn. There was a female predominance, and most patients were younger than 20 years. Fifteen patients first visited a medical doctor and 9 visited a dentist before being referred to our department. The average duration from the time the lesion was first noticed to the patient's visit was 3.6 months. All lesions were located on the ventral surface of the tongue. In 17 patients, mucoceles were seen at the tip of the tongue, whereas 9 lesions occurred more posteriorly. Lesions were situated at the midline in 19 patients and laterally in 7 patients. All lesions presented as an exophytic mass, often with a polypoid appearance. All mucoceles were histopathologically of the extravasation type, suggesting that trauma may represent a frequent initiating factor.  相似文献   
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OBJECTIVE: The aim of this study was to evaluate color compatibility of corresponding resin composite shades keyed to Vitapan Classical shade guide (Vita). METHOD AND MATERIALS: Twenty-one shades of 6 commercial resin composites were analyzed. Specimens (n = 5) were made as disks, 11 mm in diameter and 2 mm thick, using cylindrical molds. Specimens were polymerized according to manufacturers' suggestions using a light-curing unit. Data were collected using a spectrophotometer and analyzed using the appropriate color difference metric equations. A total color difference (deltaE*ab) greater than or equal to 3.7 was considered a mismatch. Analysis of variance and Fisher's probable least-squares difference (PLSD) test. intervals for comparison of means were calculated at the .05 level of significance. RESULTS: Mean deltaE*ab values among A2, B2, C2, and opaque A2 shade pairs were 4.4 (1.8), 7.3 (3.2), 5.6 (2.8), and 6.5 (1.8), respectively, while the mean color difference for all the pairs compared was 5.8 (2.8). For A2 shades, deltaL*, deltaa*ab, and deltab*ab values ranged by 5.3, 2.3, and 6.7, respectively. Corresponding values for B2 shades ranged by 10.5, 2.2, and 11.5; 7.9, 2.2, and 4.3 for C2 shades; and 7.9, 1.4, and 4.4 for opaque A2 shades. Fisher's PLSD critical intervals for comparing deltaE*ab values among the shades and composite pairs were 0.07 and 0.15, respectively (P < .0001, power 1.00). CONCLUSION: Overall, poor color compatibility of shade pairs of identical shade designation was recorded. The best color match was recorded for A2 shade pairs, followed by C2, B2, and opaque A2 shade pairs.  相似文献   
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To assess the usefulness of CT images for the diagnosis of suspected odontogenic maxillary sinusitis, 52 patients with maxillary sinusitis who had received CT examination were retrospectively analyzed. maxillary sinus ostium was established on coronal CT image in 20 out of 55 lesions in those 52 patients. However, a considerable number of patients who had inflammatory disease not only in the maxillary sinus but also in other paranasal sinuses (38/55) or in the nasal meatus (34/55) were included in those 52 patients. Concerning the opening of the ostium, the clinical diagnosis is frequently different from the diagnosis made using CT. The CT findings of the maxillary sinus ostium, nasal meatus and other paranasal sinuses were thus important in planning the treatment for patients with maxillary sinusitis in dentistry, as in otorhinolaryngology.  相似文献   
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The aim of this study was to clarify the adjunctive effect of enamel matrix derivative (EMD) on expanded polytetrafluoroethylene membrane guided tissue regeneration (GTR)-based root coverage by creating gingival recessions in beagle dogs. Recessions were treated with GTR + EMD, GTR alone, or neither GTR nor EMD (control). The control group was characterized by long junctional epithelium and little bone formation. The GTR + EMD group showed a statistically significant increase (P < .01) in new bone and cementum formation compared with the GTR group. The results of the present investigation suggest that the adjunctive use of EMD with GTR promotes formation of new bone and cementum without root resorption in recession-type defects in dogs.  相似文献   
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Cerebral blood flow (CBF) during dynamic exercise has never been examined quantitatively using positron emission tomography (PET). This study investigated changes in CBF that occur over the course of a moderate, steady-state cycling exercise. Global and regional CBF (gCBF and rCBF, respectively) were measured using oxygen-15-labeled water (H215O) and PET in 10 healthy human subjects at rest (Rest), at the onset of exercise (Ex1) and at a later phase in the exercise (Ex2). At Ex1, gCBF was significantly (P<0.01) higher (27.9%) than at Rest, and rCBF was significantly higher than at Rest in the sensorimotor cortex for the bilateral legs (M1Leg and S1Leg), supplementary motor area (SMA), cerebellar vermis, cerebellar hemispheres, and left insular cortex, with relative increases ranging from 37.6% to 70.5%. At Ex2, gCBF did not differ from Rest, and rCBF was significantly higher (25.9% to 39.7%) than at Rest in only the M1Leg, S1Leg, and vermis. The areas showing increased rCBF at Ex1 were consistent with the central command network and the anatomic pathway for interoceptive stimuli. Our results suggest that CBF increases at Ex1 in parallel with cardiovascular responses then recovers to the resting level as the steady-state exercise continues.  相似文献   
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