全文获取类型
收费全文 | 2766篇 |
免费 | 291篇 |
国内免费 | 1篇 |
专业分类
耳鼻咽喉 | 83篇 |
儿科学 | 230篇 |
妇产科学 | 107篇 |
基础医学 | 154篇 |
口腔科学 | 180篇 |
临床医学 | 287篇 |
内科学 | 550篇 |
皮肤病学 | 65篇 |
神经病学 | 223篇 |
特种医学 | 145篇 |
外科学 | 612篇 |
综合类 | 11篇 |
预防医学 | 89篇 |
眼科学 | 97篇 |
药学 | 164篇 |
中国医学 | 3篇 |
肿瘤学 | 58篇 |
出版年
2024年 | 12篇 |
2023年 | 78篇 |
2022年 | 28篇 |
2021年 | 114篇 |
2020年 | 84篇 |
2019年 | 123篇 |
2018年 | 188篇 |
2017年 | 135篇 |
2016年 | 208篇 |
2015年 | 177篇 |
2014年 | 223篇 |
2013年 | 388篇 |
2012年 | 136篇 |
2011年 | 103篇 |
2010年 | 157篇 |
2009年 | 89篇 |
2008年 | 61篇 |
2007年 | 26篇 |
2006年 | 75篇 |
2005年 | 82篇 |
2004年 | 18篇 |
2003年 | 34篇 |
2002年 | 38篇 |
2001年 | 56篇 |
2000年 | 66篇 |
1999年 | 57篇 |
1998年 | 58篇 |
1997年 | 53篇 |
1996年 | 50篇 |
1995年 | 33篇 |
1994年 | 24篇 |
1993年 | 24篇 |
1992年 | 8篇 |
1991年 | 13篇 |
1990年 | 9篇 |
1989年 | 6篇 |
1988年 | 4篇 |
1987年 | 1篇 |
1985年 | 1篇 |
1984年 | 2篇 |
1983年 | 1篇 |
1982年 | 3篇 |
1980年 | 1篇 |
1978年 | 3篇 |
1974年 | 2篇 |
1972年 | 1篇 |
1962年 | 1篇 |
1960年 | 2篇 |
1947年 | 1篇 |
1935年 | 1篇 |
排序方式: 共有3058条查询结果,搜索用时 10 毫秒
71.
ObjectiveTo determine if cervical vestibular evoked myogenic potentials (cVEMPS) differ in patients with migraine without aura (MoA), vestibular migraine (VM) and tension type headache (TTH).MethodsTwenty patients with MoA, 24 patients with VM and 20 patients with TTH were included in the study. Thirty healthy volunteers of comparable age and gender were taken as the control group. The latencies of peaks p13 and n23, peak-to-peak amplitude of p13–n23 divided by a mean prestimulus EMG recorded during cVEMP testing were measured. The amplitude asymmetry between right and left sides was also calculated and taken into consideration. Caloric testing was conducted to check if the results are associated with the results of the cVEMPs.ResultsFive (one on the right, four on the left side) of the 24 patients with VM (20.8%) displayed a unilateral caloric hypofunction. Normal results were recorded from patients with MoA and TTH. p13, n23 latencies and amplitudes of the patient groups were not statistically different from the results of the healthy controls (p > 0.05). An amplitude asymmetry between right and left sides exceeding that of the healthy controls was not also present (p > 0.05).ConclusionsThough a hypofunctioning horizontal semicircular canal was detected in 20.8% of the patients with VM, saccular function seemed to be unaffected. Patients with MoA and TTH did not display any vestibular test abnormality.SignificancePrimary headache disorders seem to be associated with a normal interictal cVEMP profile. 相似文献
72.
Dr Aslihan Sayin Gül Özsoylar Selçuk Candansayar Çetin Etik Yasin Genç Behçet Cosar 《International journal of psychiatry in clinical practice》2013,17(2):99-106
ObjectiveThe postpartum period represents a time of increased risk for psychiatric disorders. Postpartum depression is especially very common. Many aetiological risk factors have been reported for postpartum psychiatric disorders. The purpose of this study was to evaluate the postpartum psychiatric disorders in a Turkish sample and discuss their course.MethodsThe files of 6000 inpatients who were admitted to Gazi University School of Medicine Psychiatry Department were evaluated retrospectively, and 67 patients were chosen whose psychiatric illness had began puerperally. These patients were grouped according to age of onset of the illness, number of episodes and the type of these episodes, their postpartum psychiatric diagnoses and illness prognosis.ResultsOf 6000 patients, 67 (1.11%) were diagnosed as having a postpartum psychiatric disorder: 56.7% (n=38) were diagnosed as having a postpartum psychotic disorder, while 35.8% (n=24) as having an affective disorder. Forty-seven patients (70.1%) received a diagnosis of major psychiatric disorder during their follow-up.ConclusionThese results show that postpartum diagnoses may show a chronic course and cause a life-time psychiatric illness and therefore patients should be monitored carefully for psychotic symptoms even after the acute period is over. 相似文献
73.
IntroductionSome improvements have been developed with new generations of nickel-titanium (NiTi) rotary instruments that led to their successful and extensive application in clinical practice. The purpose of this in vitro study was to compare the root canal preparations performed by using GT Series X and Twisted File systems produced by innovative manufacturing process with Revo-S, RaCe, Mtwo, and ProTaper Universal systems manufactured directly from conventional nitinol and with stainless steel K-Flexofile instruments.MethodsThe mesiobuccal root canals of 140 maxillary first permanent molars that had between 30°–40° curvature angle and 4- to 9-mm curvature radius of the root canal were used. After root canal preparations made by using GT Series X, Twisted File, Revo-S, RaCe, Mtwo, and ProTaper Universal NiTi rotary systems and stainless steel K-Flexofile instruments, transportation occurred in the root canal, and alteration of working length (WL) was assessed by using a modified double-digital radiographic technique. The data were compared by the post hoc Tukey honestly significant difference test.ResultsNiTi rotary systems caused less canal transportation and alteration of WL than K-Flexofile instruments (P < .05). There was no significant difference between NiTi rotary system groups at any levels (P > .05) except 2.5 mm from the WL. At this level ProTaper Universal system caused significant canal transportation (P < .05).ConclusionsGT Series X and Twisted File rotary systems produced with innovative process were concluded to shape the curved canals to result in minimal canal transportation, similar to Revo-S, RaCe, Mtwo, and ProTaper Universal rotary systems manufactured by traditional methods. 相似文献
74.
Çağdaş Çınar Didem Atabek Mesut E. Odabaş Ayşegül Ölmez 《International dental journal》2013,63(2):97-102
The aim of this in vivo study was to evaluate the performance of fluorescence‐based devices in detecting occlusal caries lesions in primary molars compared with conventional methods. Two examiners assessed 44 occlusal surfaces of first and second primary molars in 20 patients using two fluorescence devices: DIAGNOdent (LF) and DIAGNOdent pen (LFpen). Teeth were also assessed by visual examination and bitewing radiograph. Histological examination served as the gold standard after extraction. By using the McNemar test, the sensitivity, specificity, accuracy, and area under the receiver operating curve were calculated as outer enamel (D1), inner enamel (D2) and dentine caries (D3) lesion thresholds. The intra‐ and inter‐examiner reproducibility were calculated using the Cohen's unweighted kappa statistics. At the D1 threshold, the LFpen sensitivity was statistically higher than LF and radiographic examination (P < 0.001), whereas there was no statistically significant difference among the groups at the D2 and D3 thresholds (P > 0.05). All methods demonstrated the highest sensitivity values at D3. At the D1 and D2 thresholds, there were no significant differences between the LFpen specificity and the other methods. All methods presented similar performance in detecting all lesions considering the area under the receiver operating curve. The LFpen showed better performance than LF. Furthermore, visual examination and the LFpen device seem to be sufficient for detection of occlusal caries in primary molars. 相似文献
75.
Binali Çakur DDS PhD Muhammed Akif Sümbüllü DDS PhD Doğan Durna DDS 《Clinical implant dentistry and related research》2013,15(1):83-87
Background: Osseo‐integrated implants are increasingly being used to restore functional dentition; however, in the posterior region, implant placement can be problematic because of inadequate bone height. In this condition, maxillary sinus floor elevation surgery has become the treatment of choice. The presence of anatomic variations within the maxillary sinus such as Underwood's septa and thin schneiderian membrane decreases the success of the sinus floor elevation. Purpose: In this study, we tried to determine the relationship between the anatomic variations of the maxillary sinus: Underwood's septa, schneiderian membrane thickness, and the cortical thickness of the inferior border of the maxillary sinus. Material and Methods: The left and right maxillary sinus images of 74 patients were obtained by using dental computed tomography (CT). The schneiderian membrane and the cortical thickness of the inferior border of the maxillary sinus were measured on the coronal images of dental CT scans at the deepest portion of the sinus cavity. The presence of Underwood's septa was identified on the axial images. The correlations between these variables were assessed. Results: We found that there was only a negative correlation between the schneiderian membrane thickness and the presence of Underwood's septa (r = –0.168 p = .042). Conclusion: It is suggested that Underwood's septa may be the reason for the thinness of the schneiderian membrane. However, future studies among larger groups are necessary for confirming the finding by using well‐designed clinical studies. 相似文献
76.
Erhan Özcan Ali Riza Çetin İsmail Davut Çapar Ali Riza Tunçdemir Hale Ari Aydinbelge 《Odontology / the Society of the Nippon Dental University》2013,101(2):204-209
This study evaluated the influence of eugenol on the push-out bond strengths of fiber posts cemented with different types of resin luting agents. Seventy-two extracted maxillary single-rooted canine teeth were randomly divided into two groups of 36 teeth. Group 1, the control group, was filled with gutta-percha only (i.e., did not receive eugenol), whereas group 2 was filled with a eugenol-containing sealer. All root canals were filled and each group was divided into three subgroups. The posts in each subgroup were cemented with the following materials: subgroup 1 with a 2-step self-etching adhesive system (Clearfil Liner Bond 2V + Panavia F); subgroup 2 with a 1-step self-etching adhesive (Panavia F); and subgroup 3 with a self-adhesive (Clearfil SA Cement). Dislodgement resistance was measured using a universal testing machine. All data were subjected to ANOVA using a factorial design and Tukey test (α = 0.05). The use of the eugenol-containing sealer significantly reduced the push-out bond strength of the fiber post (P < 0.05). The push-out bond strength of Panavia F was significantly higher than those of the other groups filled with the eugenol-containing sealer (P < 0.05). The Panavia F group was less susceptible to the inhibiting effect of eugenol than were the other evaluated groups when the fiber post was cemented in the canals filled with the eugenol-containing sealer. 相似文献
77.
Necati Tatarlı Davut Ceylan Hüseyin Canaz Mehmet Tokmak Hüsniye Hacıoğlu Bay Aşkın Şeker Evren Keleş Türker Kılıç Safiye Çavdar 《Acta neurochirurgica》2013,155(11):2183-2189
Background
Only limited attention has been paid to the anatomy and clinical importance of the falcine venous plexus. The aim of this study was to evaluate the falcine venous plexus anatomically using scanning electron microscopy (SEM), and to provide guidance for neurosurgical approaches.Methods
Latex or ink was injected into the superior and inferior sagittal sinus. The falcine venous plexus lying within the connective tissue of the falx cerebri was observed by dividing the falx into thirds (anterior, middle and posterior). Further, the SEM appearance of the falcine venous plexus was evaluated.Results
The anterior third of the falx cerebri consisted of small diameter falcine venous vessels. These vessels were localized close to either the superior or inferior sagittal sinus, and none extended as far as mid-falx cerebri levels in any of the 16 cases. They communicated with either superior or inferior sagittal sinuses, but not with both of these sinuses. In the middle third of the falx cerebri, the majority of the vessels of the falcine venous plexus had larger diameter compared to those of the anterior third. These vessels extended the length of the falx cerebri levels. They communicated with both superior and inferior sagittal sinuses. In the posterior third of the falx cerebri, the vessels of the falcine venous plexuses had the largest diameter and were located at the junction of the inferior sagittal sinus and the straight sinus. They were localized at the lower two-thirds of the falx cerebri. In all cases, the dense venous networks communicated with the inferior sagittal sinus but not with the superior sagittal sinus. The falcine venous plexus observed in the posterior third of the falx cerebri was denser than in the anterior and middle portions. The SEM revealed small vessels whose diameter ranged between 42 and 138 μm. The vessels of the falcine venous plexus in the anterior third had a mean diameter of 0.42?±?0.1 mm, in the middle third a mean diameter of 0.87?±?0.17 mm, and in the posterior third, 1.38?±?0.21 mm.Conclusion
The falcine venous plexus is a network of venous channels that exists within the connective tissue of the falx; the sizes and patterns of communication of these structures showed regional differences. Neurosurgeons should be aware of the regional differences when making an incision or puncturing the falx during a surgical approach. 相似文献78.
Fatma Çağlayan Murat Çakmak Osman Çağlayan Turgut Çavuşogˇlu 《Journal of investigative surgery》2013,26(4):233-237
We investigated the possible use of D -lactate as a predictor in the diagnosis of appendicitis. C-reactive protein level (CRP) and leukocyte counts were also evaluated. Venous blood D -lactate, CRP, and leukocyte counts were measured preoperatively in 53 patients undergoing surgery for appendicitis, as well as in 20 healthy subjects. Levels of all three parameters in the surgical patients were significantly higher than in the control group ( p < .05). Previous studies have shown that venous D -lactate is more specific to the intestine than CPR or leukocyte count. Based on our data, venous D -lactate, which had the lowest false-negative rate among these laboratory parameters, may be a useful diagnostic marker for appendicitis. None of these parameters were helpful in identifying the type of the appendicitis. 相似文献
79.
80.
Arife Uslu Gökceoğlu Sema Akman Sadi Köksoy Emel Şahin Mustafa Koyun Elif Çomak Çağla Serpil Doğan Halide Akbaş Ayhan Dinçkan 《Pediatric nephrology (Berlin, Germany)》2013,28(12):2377-2382