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31.
Oxidative stress induced by spinal cord injury (SCI) has deleterious effects on the function of several organ systems including the urinary bladder. In this study, we investigated the possible protective actions of melatonin on SCI-induced oxidative damage and urinary bladder dysfunction. Wistar albino rats (n = 24) were divided randomly as control, vehicle- or melatonin (10 mg/kg, ip)-treated SCI groups. To induce SCI, a standard weight-drop method that induced a moderately severe injury at T10 was used. Injured animals were given either vehicle or melatonin 15 min postinjury. One week postinjury, each rat was neurologically examined and then decapitated; blood samples were taken to evaluate neuron-specific enolase (NSE) and soluble protein 100β (S-100β). Spinal cord (SC) and urinary bladder samples were taken for functional studies and histological examination or stored for the measurement of malondialdehyde (MDA), glutathione (GSH) and nerve growth factor (NGF) levels and caspase-3 activity. Isometric contractions in bladder strips were induced by carbachol. In the SCI rats, decreased contractile responses of the bladder strips were found to be restored by melatonin treatment. Serum S-100β levels and NSE activities and tissue MDA levels and caspase-3 activities, all of which were elevated in the vehicle-treated SCI animals as compared to the control values, were reversed by melatonin treatment. On the other hand, reduced GSH and NGF levels due to SCI were restored by melatonin treatment. Furthermore, melatonin treatment improved histological findings. These findings suggest that melatonin reduces SCI-induced tissue injury and improves bladder functions through its effects on oxidative stress and NGF.  相似文献   
32.
Objective:To evaluate the effects of different bleaching methods on the shear bond strength (SBS) of orthodontic brackets.Materials and Methods:Forty-five freshly extracted premolars were randomly divided into three groups (n  =  15 per group). In group I, bleaching was performed with the office bleaching method. In group II, bleaching was performed with the home bleaching method. Group III served as the control. Orthodontic brackets were bonded with a light cure composite resin and cured with an LED light. After bonding, the SBS of the brackets were tested with a Universal testing machine.Results:Analysis of variance indicated a significant difference between groups (P < .001). The highest values for SBS were measured in group III (20.99 ± 2.32 MPa). The SBS was significantly lower in groups I and II than in group III (P < .001). The lowest values for SBS were measured in group II (6.42 ± 0.81 MPa). SBS was significantly higher in group I than in group II (P < .001).Conclusions:Both of the bleaching methods significantly affected the SBS of orthodontic brackets on human enamel. Bleaching with the home bleaching method affected SBS more adversely than did bleaching with the office bleaching method.  相似文献   
33.

Objective

The objective of this study is to compare the diagnostic accuracy of visual inspection (VI) and storage phosphor plate (SPP) radiography for the detection of artificial demineralization bordering different laminate veneers.

Materials and methods

Twenty human maxillary canine teeth were prepared. All-ceramic (A) and hybrid ceramic (H) laminate veneers were fabricated and luted. Veneered teeth were covered except for a circular window on the proximal surface bordering restorations. Teeth were kept in acetic acid buffer to create demineralization and imaged with a SPP system. Ten observers evaluated all teeth first visually then with SPP images for the presence/absence of demineralization. Teeth were examined using scanning electron microscopy (SEM) as well. The accuracy was expressed as the area under the ROC curves (A z). Pair-wise comparisons were performed using two-way ANOVA and post hoc t test (p?=?0.05). Fleiss kappa (κ) was used for agreement.

Results

SPP radiography was better than the VI for both veneers (p?=?0.004). The A zs of two veneers were different for both VI (p?<?0.005) and SPP (p?<?0.005). SEM evaluation revealed lesions confined to enamel. κ was fair for H, and fair to moderate for A. Agreement was higher for the radiographic evaluation for both veneers.

Conclusion

Enamel demineralizations bordering hybrid and ceramic laminate veneers can be detected better with SPP radiography than VI and detectability was better for all-ceramic veneers than the hybrid ceramic ones.

Clinical relevance

Early detection of enamel demineralizations bordering laminate veneers would result in time-saving and less-invasive treatment methods; therefore, SPP radiography may be recommended in clinically suspicious cases since it provides better diagnostic accuracy.
  相似文献   
34.
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   
35.
The purpose of this study was to evaluate the influence of different surface treatments (sandblasting, acid etching, and laser irradiation) on the shear bond strength of lithium disilicate-based core (IPS Empress 2) and feldspathic ceramics (VITA VM 9). One hundred ceramic discs were divided into two groups of 50 discs each for two ceramic systems: IPS Empress 2 (group I) and VITA VM 9 (group II). Each of the two groups was further divided into five surface treatment groups (ten each) as follows: group SB, sandblasting with alumina particles (50 μm); group HF, 5 % hydrofluoric acid etching; group L, Er:YAG laser irradiation (distance, 1 mm; 500 mJ; 20 Hz; 10 W; manually, noncontact R14 handpiece); group SB–L, sandblasting + Er:YAG laser; and group HF–L, 5 % hydrofluoric acid + Er:YAG laser. Luting cement (Panavia 2.0) was bonded to the ceramic specimens using Teflon tubes. After 24 h of water storage, a shear bond strength test was performed using a universal testing machine at a crosshead speed of 0.5 mm/min. The data were analyzed with a two-way analysis of variance (ANOVA) and Tukey's honestly significant difference tests (α?=?0.05). The two-way ANOVA indicated that the shear bond strength was significantly affected by the surface treatment methods (p?<?0.05), but there was no significant interaction between the ceramic systems. Group SB–L had the highest mean values for each ceramic system. Sandblasting, followed by Er:YAG laser irradiation, enhanced the bond strength, indicating its potential use as an alternative method. The atomic force microscopic evaluation revealed that group SB had the most distinct sharp peaks among the groups.  相似文献   
36.
The aim of the study to compare outcomes of flexible ureterorenoscopy in patients with different body mass index (BMI) scores and to explore whether the BMI has an effect on outcomes of RIRS. Five hundred and two patients who underwent flexible URS in 3 centers between 2008 and 2012 for the management of single upper urinary tract calculi were retrospectively reviewed. Patients were categorized as normal weight BMI 18.5 to 24.99 kg/m2, overweight 25 to 29.99 kg/m2, obese 30 to 39.99 kg/m2 and morbid obese >40 kg/m2.The groups were assessed in terms of demographic parameters including age, gender, stone size, intraoperative and postoperative variables. The mean patient age was 41.3 ± 15.51 (18–81) years and with an average BMI 26.68 ± 5.2 kg/m2 (16.64–55.15 kg/m²). Of the patients, 43.2 % had normal weight (NW), 32.2 % were overweight (OW), 21.9 % were obese (O) and 2.5 % were morbidly obese (MO). Stone-free rates after single procedure in NW, OW, O, MO groups were 60.8, 61.7, 73.6, 61.5 %, respectively (p = 0.079). Overall targeted stone-free rates were also similar in four groups (88.9, 90.1, 93.6, 90.4 %, p = 0.586). There were no statistically significant differences in the frequency of complications and mean hospitalization time among the groups (p > 0.05). In conclusion, this study demonstrated that flexible URS is a valuable option for the treatment of kidney stone in both obese and non-obese patients. BMI did not influence the postoperative outcomes.  相似文献   
37.
38.
Gastrointestinal system anastomoses, especially colonic anastomoses, have significant morbidity and mortality despite recent technical improvements. Besides regulating the circadian rhythm, the pineal gland and its main neurohormone product melatonin have widespread actions in the organism. The purpose of this study was to investigate the effects of pinealectomy on the healing of colonic anastomoses. One hundred male albino Wistar rats were used in this study. The rats were separated into three groups: control, pinealectomy, and sham groups. In the control group, only colonic resection and anastomoses were performed. Following pinealectomy, colonic anastomosis was performed 2 weeks later on one half and 2 months later on the other half of the pinealectomy group. Only craniotomy was performed on the sham group, and the rats were separated and evaluated like the pinealectomy group. Colonic anastomoses were evaluated on postanastomotic day 3 and 7 by measuring the bursting pressure and the hydroxyproline levels in the anastomotic segments. There was no difference in the bursting pressure measurements between the groups on both postoperative day 3 and 7. Although hydroxyproline levels were different between groups on both postanastomotic days 3 and 7, it has been observed that neither normal nor anastomotic hydroxyproline levels influenced the anastomotic bursting pressure measurements. The percent deviation from the normal values was compared in the anastomotic segments, and no differences were found regarding the bursting pressure and hydroxyproline levels. It was concluded that pinealectomy has no effect on the healing of colonic anastomoses.  相似文献   
39.
40.

Objective

Low grade gliomas (LGGs) are slow-growing primary brain tumors with heterogeneous clinical behaviors. The aim of our study is to review the treatment outcome of 63 patients with LGGs focusing on surgical outcome and the current therapeutic strategy.

Methods

We retrospectively enrolled 63 patients surgically treated for LGGs. The gross total resection (GTR) was performed in 35 patients (60.3%), subtotal resection (STR) was performed in 19 patients (31.7%) and partial resection (PR) or biopsy was performed in 9 patients (14.3%). We analyzed their progression-free survival (PFS), overall survival (OS), and malignant transformation with regard to age, gender, Karnofsky performance score (KPS), clinical presentation, tumor location, radiologic pattern, contrast enhancement, extent of removal, pathologic subtype, chemotherapy (CT) and radiotherapy (RT) treatment.

Results

Among all LGGs, the 3-year OS rate was 80% and the 5-year OS was 76%. The 3-year PFS rate was 83.6% and the 5-year PFS was 25%. The non-eloquent area location showed a longer PFS than the eloquent area location (p = 0.05). Oligodendroglial pathology showed a longer PFS compared to oligoastrocytomas and astrocytomas (p = 0.02). Patients older than 60 years had poorer OS than younger patients (p < 0.05). Female gender had a shorter OS than male gender (p < 0.05), and a KPS of 90 or 100 had a longer OS than a KPS of 80 (p < 0.05). Oligodendroglial pathology statistically correlated with a longer OS (p < 0.05).

Conclusion

The findings from our study, which were confirmed by uni- and multivariate analyses, demonstrated that radical tumor resection was associated with better long-term outcomes and tumor progression for patients with LGG.  相似文献   
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