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1.
Bone regeneration in orthodontically produced alveolar bone dehiscences   总被引:1,自引:0,他引:1  
Orthodontic appliances, designed to tip the maxillary second and third incisors in facial direction, were inserted in 3 dogs. During a 5 month period, the incisors on the left side of the jaw were tipped to a facially displaced position. During a further 5 month period these teeth were moved back to their original position while the two incisors on the right side of the jaw were moved to a position corresponding to that previously reached by the incisors of the left side. The orthodontic appliances were then used to retain the teeth In these positions for 5 months. Teeth in three non-treated dogs served as controls. During the study, the animals were subjected to meticulous plaque control. The animals were sacrificed 15 months after the start of the study. The jaws were removed and buccolingually oriented histological sections of the experimental and control teeth were produced. The study has shown (1) that dehiscences can be produced in the alveolar bone by tipping teeth in facial direction and that bone will reform in such defects when the teeth are moved back to their original position and (2) that such tooth movements are not necessarily accompanied by loss of connective tissue attachment.  相似文献   
2.
With today's widespread use of fluoride, the nature of cavities has changed. Harder, and therefore more resistant enamel can many times conceal subsurface decay and the caries disease progresses, in many cases, for a prolonged period with low activity and slow progression. The change in pattern of the caries disease calls for a shift in treatment philosophy; the original maxim of ‘extension for prevention’ has been eschewed for a minimal intervention approach, although this approach is only effective if caries is diagnosed at an early stage. Incorrect diagnosis results in incorrect treatment decisions. In the current age of lower overall prevalence of decay and slow disease progression, the potential risk of unnecessary restorations is greater than the risk of missing early decay. As an adjunct to conventional caries diagnostic methods such as visual inspection and bitewing radiography, a need for objective quantitative detection methods is of high importance. KaVo DIAGNOdentTM (KaVo Dental, Biberach, Germany) is a laser fluorescence device developed for caries detection and quantification as an adjunct to visual inspection and radiographic examination. The aim of this in vitro study was to investigate the stability of the instrument for longitudinal measurements. The study was carried out in two subsequent parts where measurements were performed in two series, with and without calibration. The material in Part I of the study comprised 30 extracted teeth with various stages of carious lesions measured with one DIAGNOdentTM device. In Part II, two devices were used to determine their unanimity and measurements were performed on six fluorescence standards in order to minimize false positive readings. The first series in Part I, with only one initial calibration, showed a significant change over time: a linear trend with drifting towards lower readings (P < 0.001). In the second series, with frequent calibrations, no significant linear trend over time could be demonstrated (P = 0.09). Clinically relevant differences in mean value between the series of measurements were seen over time (without frequent calibration, 7.64; with frequent calibration 8.57). The mean value of readings from the series with frequent calibrations was approximately 1 unit higher throughout the study, and single observations were 1–6 units higher. Results from Part II showed a significant systematic over‐time difference between the factor ‘without’ and ‘with’ calibration (P = 0.0023) independent of which device that was used (P = 0.67). There was no significant difference between the devices, DDI and DDII (P = 0.14). The interaction, time × calibration, was significant (P < 0.000) with stable readings over time in the period ‘with calibration’, while the readings in the period ‘without calibration’ was drifting towards lower readings from day 1 and forward. From this in vitro study it was concluded that frequent calibration of DIAGNOdentTM should be performed in order to obtain comparable data for longitudinal monitoring.  相似文献   
3.
The aim of this double-blind, controlled crossover study was to evaluate the influence of food preservatives on in situ dental biofilm growth. Twenty-four volunteers wore appliances with six specimens each of bovine enamel to build up intra-oral biofilms. During three test cycles, the subjects had to put one half of the appliance twice a day in one of the assigned active solutions (0.1% benzoate, BA; 0.1% sorbate, SA or 0.2% chlorhexidine, CHX) and the other into NaCl. After 5 days, the developed biofilms were stained with two fluorescent dyes to visualise vital (green) and dead bacteria (red). Biofilms were scanned by confocal laser scanning microscopy and biofilm thickness (BT) and bacterial vitality (BV%) were calculated. After a washout period of 7 days, a new test cycle was started. The use of SA, BA and CHX resulted in a significantly reduced BT and BV compared to NaCl (p < 0.001). Differences between SA and BA were not significant (p > 0.05) for both parameters, while CHX showed significantly lower values. Both preservatives showed antibacterial and plaque-inhibiting properties, but not to the extent of CHX. The biofilm model enabled the examination of undisturbed oral biofilm formation influenced by antibacterial components under clinical conditions.  相似文献   
4.
The clinical behavior of central giant cell granuloma (CGCG) of the jaws is variable and difficult to predict. Clinical data and follow-up information of 26 patients with CGCG were analyzed. Histologic features were correlated with the clinical course of the disease. In 16 patients the CGCGs were asymptomatic; 10 lesions presented with aggressive growth, pain, massive swelling, root resorption, cortical perforation, and/or recurrence. These patients were younger and the lesions were larger than in the nonaggressive group. The histomorphometric analysis proved a significant increase in large giant cells, fractional surface area, and mitotic activity in aggressive CGCG lesions. Immunohistologic investigation (Ki-67 and p53 stain) revealed no significant differences. After surgical treatment, 3 patients with aggressive lesions developed a recurrence. The data show that clinical and histomorphometric features may be reliable indicators for the differentiation between aggressive and nonaggressive CGCG. This should be accounted for to improve the individual planning of the treatment and follow-up.  相似文献   
5.
Katathym Imaginative Psychotherapy (KIP)/Guided Affective Imagery (GAI) as well as psychodrama use an imaginary space in which fantasy and creativity are stimulated, regression is allowed in the service of the self and experiential and cathartic processes are all used therapeutically. On the other hand at different levels, scene and action along with contact, physical movement and kinesthetic experience, become real (Berger-Becker and Grothaus-Neiss 2012). In KIP this happens in an imaginative manner, in psychodrama it works by real action, by which spatial dimension and conflict are more clearly delineated. The case vignette described here of a psychodynamic long term therapy in which KIP as well as psychodrama were used, exemplifies the suitability of the combined application of both methods.  相似文献   
6.
Cortical superficial siderosis (cSS) is a magnetic resonance imaging marker of cerebral amyloid angiopathy (CAA) and can be its sole imaging sign. cSS has further been identified as a risk marker for future intracranial hemorrhage. Although uncommon in the general population, cSS may be much more prevalent in high risk populations for amyloid pathology. We aimed to determine the frequency of cSS in patients with cognitive impairment presenting to a memory clinic. We prospectively evaluated consecutive patients presenting to our memory clinic between April 2011 and April 2013. Subjects received neuropsychological testing using the Consortium to Establish a Registry for Alzheimer’s Disease battery (CERAD-NP). Two hundred and twelve patients with documented cognitive impairment further underwent a standardized 3T-MR-imaging protocol with T2*-weighted gradient-echo sequences for detection of cSS. Thirteen of 212 patients (6.1 %) displayed cSS. In seven of them (54 %) cSS was the only imaging sign of CAA. Patients with cSS did not differ from patients without cSS with regard to medical history, age or cardiovascular risk profile. Subjects with cSS performed worse in the mini-mental state examination (p = 0.001), showed more white matter hyperintensities (p = 0.005) and more often had microbleeds (p = 0.001) compared to those without cSS. cSS is common in patients with cognitive impairment. It is associated with lower cognitive scores, white matter hyperintensities and microbleeds and can be the only imaging sign for CAA in this patient group.  相似文献   
7.
8.

Objective

The use of antibacterial photodynamic therapy (aPDT) additionally to scaling and root planing (SRP) has been shown to positively influence the clinical outcomes. However, at present, it is unknown to what extent aPDT may represent a potential alternative to the use of systemic antibiotics in nonsurgical periodontal therapy in patients with aggressive periodontitis (AP). The aim of this study was to evaluate the outcomes following nonsurgical periodontal therapy and additional use of either aPDT or amoxicillin and metronidazole (AB) in patients with AP.

Material and methods

Thirty-six patients with AP displaying at least three sites with pocket depth (PD) ≥6 mm were treated with SRP and either systemic administration of AB for 7 days or with two episodes of aPDT. The following clinical parameters were evaluated at baseline and at 6 months: plaque index (PI), bleeding on probing (BOP), PD, gingival recession (GR) and clinical attachment level (CAL).

Results

Thirty-five patients have completed the 6-month evaluation. At 6 months, mean PD was statistically significantly reduced in both groups (from 5.0?±?0.8 to 3.0?±?0.6 mm with AB and from 5.1?±?0.5 to 3.9?±?0.8 mm with aPDT (p?p?p?p?=?0.03). Both therapies resulted in statistically significant reductions in all parameters compared to baseline.

Conclusion

While both treatments resulted in statistically significant clinical improvements, AB showed statistically significantly higher PD reduction and lower number of pockets ≥7 mm compared to aPDT.

Clinical relevance

In patients with AP, the two times application of aPDT in conjunction with nonsurgical periodontal therapy cannot be considered an alternative to the systemic use of amoxicillin and metronidazole.  相似文献   
9.

Background

The pathogenesis of intestinal dysmotility in gastroschisis is not completely understood. Peel formation and disorganization of interstitial Cajal cells (ICC) have been proposed in humans. The aim of this study was to evaluate the impact of prenatal coverage of gastroschisis on gut inflammation and expression of ICC in a fetal lamb model.

Methods

Twenty-one German blackhead sheep with an abdominal wall defect that was created fetoscopically on day 77 of 145 days gestation were used in this study. Intrauterine surgery with the aim to cover the defect was performed 3 weeks later; two fetuses were covered completely, 5 partially and 11 remained uncovered. Three fetuses without gastroschisis were used as controls. All fetuses were retrieved by cesarean section at day 135. Samples of the small intestine were stained with hematoxylin and eosin for histologic analysis of peel formation and serosal and muscular thickness. For ICC detection, immunohistochemistry using anti-CD117 (c-Kit) antibody was used.

Results

In all samples with exposure to amniotic fluid, peel formation and significantly decreased ICC were found. Complete coverage reduced peel formation and disorganization of ICC compared to uncovered animals almost to the level of controls.

Conclusions

Peel formation and ICC derangement were significantly reduced by prenatal coverage of gastroschisis. Moreover, this animal model mimics the histopathological bowel changes as seen in human gastroschisis and may, therefore, be used for further research on the pathophysiology and fetal therapy of this malformation.  相似文献   
10.
We present a case of supraventricular tachycardia affecting one fetus in a twin pregnancy. Before and after treatment with flecainide and cardioversion, we examined conduction times and heart rate variability (HRV) in both twins on the basis of magnetocardiography. Cardiac conduction times increased in both fetuses but HRV showed opposing effects with a number of HRV measures. This case demonstrates that magnetocardiography not only enables identification of fetal arrhythmia, but also permits the investigation of the effects of antiarrhythmic treatment on the conductive system as well as on interaction with the autonomic nervous system.  相似文献   
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