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Several studies indicate that thrombosis plays an important role in the pathogenesis of coronary heart disease (CHD). Fibronectin is a multifunctional protein in plasma, other body fluids, and cell surface and plays an important role in platelet functions, including mediation of cell-cell and cell-surface interactions. Sialic acid is a regular constituent of glycoproteins and gangliozides in the outer cell membrane of mammalian cells. Therefore, the sialic acid content of platelets, which are characterized by their ability to aggregate with each other, can be important in leading to thrombus formation. In this study, platelet fibronectin, sialic acid-, and adenosine diphosphate (ADP)-induced platelet aggregation levels were determined in patients with CHD. Platelet sialic acid concentrations were determined by Warren's method. Platelet aggregation tests with ADP in platelet-rich plasma (PRP) were analyzed by use of an aggregometer. Platelet homogenate fibronectin levels were determined by ELISA. Total protein levels were determined by Lowry method. Our results indicate that, in patients with no vessel disease (patients with no obstructed vessel but suffering from chest pain, like angina pectoris) platelet fibronectin levels were significantly lower than the total of the other patients (patients with 1, 2, or 3 obstructed coronary vessels) (p<0.05). Sialic acid levels in patients with no vessel disease were significantly lower than the total of the patient group (p<0.05). There was significant (+) correlation between platelet aggregation, platelet fibronectin, platelet sialic acid, and severity of disease (p<0.05). Our preliminary findings suggest that, especially platelet fibronectin levels potentially represent a pathogenic factor for CHD.  相似文献   
3.

Purpose

Retina is a unique part of the central nervous system (CNS) for visualizing the processes of axonal and neuronal degeneration. Optical coherence tomography (OCT) allows direct visualization and measurement of retinal nerve fiber layer (RNFL) thickness, macular volume, and optic disc (OD) parameters. One of the disorders associated with atrophy in different brain regions is obstructive sleep apnea syndrome (OSAS). In the present study, we aimed to determine OD and RNFL changes measured by OCT for investigating the progress of neurodegeneration development in OSAS, excluding all the other conditions that can directly affect RNFL thickness and optic nerve parameters.

Methods

Both eyes of 101 patients with OSAS and 20 controls were investigated by OCT. Full-night polysomnography (PSG) and ophthalmologic examination including automated visual field (VF) examination and OCT were performed in all of the patients.

Results

According to the OSAS grading, patients were grouped as mild (n?=?15), moderate (n?=?27), and severe (n?=?59). We found significant decrease in RNFL thickness only in the patients with severe OSAS compared with the other groups and decreased macular ganglion cell thickness in the severe OSAS group compared with the control group. VF parameters were significantly worsened in all the OSAS subgroups compared to the control group. We found different data such as normal or increased optic nerve parameters as result of subtle OD edema, which may mask possible peripapillar axonal loss.

Conclusions

We think that evaluation of neurodegeneration in OSAS is not always possible by examining OD and RNFL because there are difficulties due to the confounding issues of cerebral atrophy and OD edema.  相似文献   
4.

Background

To find the most efficacious method to minimize the side effects and maximize the advantages of laparoscopic surgery, this study aimed to define and document a gasless, single-incision abdominal access technique for the management of benign ovarian cysts.

Methods

During a 1½ year period, 55 women underwent surgery for a benign ovarian cyst. Conventional carbon dioxide (CO2) laparoscopy was used for 33 of the women, and 22 of the women underwent a novel, gasless, single-incision laparoscopic surgery. An abdominal access pathway through a single intraabdominal incision was used to place transabdominal sutures that elevated the abdominal wall, and the operations were performed through the intra-umbilical entry without the use of trocars. Thus, the new technique was called keyless abdominal rope-lifting surgery (KARS). Two operative groups were compared to assess the feasibility of the new technique.

Results

All the operations could be performed by KARS without conversion to CO2 laparoscopy or laparotomy. However, for two patients in the conventional laparoscopy group, minilaparotomy had to be performed for tissue retrieval. Although the two techniques had many similar results, the total operative times and the abdominal access times in the KARS group were significantly longer than in the conventional laparoscopy group (p < 0.05). Simple oral analgesics were adequate for postoperative pain relief in both groups.

Conclusions

The KARS technique is a gasless, single-incision laparoscopic procedure that can be performed safely and effectively in terms of cosmesis, postoperative pain, and fertility preservation for the management of benign adnexal pathologies.  相似文献   
5.
PURPOSE: In this in-vitro study, microleakage of all-ceramic crowns was evaluated at enamel and dentin margins. MATERIALS AND METHODS: Forty maxillary central incisors were randomly divided into 4 groups (n = 10). While buccal and palatal margins were placed on enamel, mesial and distal margins were placed below the cementoenamel junction. In groups 1 to 3, IPS Empress 2 crowns were luted with Variolink 2/Syntac Classic (group 1), Bifix DC/Solobond Plus (group 2) and Calibra/Prime & Bond NT combinations (group 3), respectively. In the control group (group 4), porcelain-fused-to-metal crowns were luted with a zinc-phosphate cement. All specimens were subjected to 5000 thermocycles (at 5 degrees C to 55 degrees C; 30-s dwell time). After immersion in India ink for 48 h at 37 degrees C, the specimens were sectioned both buccolingually and mesiodistally. Each section was evaluated for microleakage under a stereomicroscope at 24X magnification. RESULTS: According to the Krukal-Wallis test, in all groups, there were significant differences in microleakage at the enamel margins (p = 0.001). Nevertheless, the margins finished in dentin showed no significant differences (p = 0.163). According to the Mann-Whitney U-test, statistically significant differences were observed in microleakage between groups 1 and 3 (p = 0.049), groups 1 and 4 (p = 0.001), groups 2 and 4 (p = 0.002), and between groups 3 and 4 (p = 0.045) at the enamel margin. In group 1, significantly greater microleakage was observed at the dentin margin compared to the enamel margin (p = 0.007). CONCLUSION: The adhesive luting technique demonstrated an excellent ability to minimize microleakage of all-ceramic crowns at the enamel margins. Water-based dentin bonding systems showed less microleakage than the water-free acetone-based dentin bonding system at the enamel margin.  相似文献   
6.
OBJECTIVE: To examine the incidence of recurrence and progression in patients with stage T1, grade-3 carcinoma of the bladder treated with endovesical bacillus Calmette-Guérin (BCG) after complete transurethral resection. MATERIAL AND METHODS: From May 1995 to June 2002, 937 patients with superficial bladder cancer underwent transurethral resection. 46 patients (4.9%) had T1G3 tumors. All patients received endovesical BCG therapy 2-3 weeks after transurethral resection, given in 6 sessions as weekly instillations of 120 ml Pasteur strain BCG in 50 ml saline. Success was defined by normal cytology and cystoscopy, and normal bladder biopsies. Recurrent tumors were resected and a second or third cycle of therapy was given according to pathological status. Progressive tumors were managed by radical cystectomy, radiotherapy and/or chemotherapy depending on the nature of the tumor or clinical status of the patient. RESULTS: During follow-up 60.7% of the patients (28 of 46) remained tumor free after only 1 BCG cycle and 73.9% (34 of 46) after the third BCG cycle, and the bladder was preserved in all. Muscle-invasive progression was noted in 10 (21.7%) patients at the end of the BCG cycles. Radical cystectomy was done in 10 patients. The tumor-free survival rate of all patients including those who underwent cystectomy is 84.8% (39 of 46) with a median follow-up of 61 (range 39-118) months. CONCLUSION: Adjuvant immunotherapy with BCG after complete transurethral resection of the bladder tumor represents a highly effective treatment for bladder preservation in stage pT1, grade-3 carcinoma of the bladder. pT1G3 tumors with early high-grade recurrence after failed immunotherapy should be regarded as candidates for early radical cystectomy.  相似文献   
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8.
Effect of length and diameter of tapered posts on the retention   总被引:6,自引:0,他引:6  
The force transmission of tapered unthreaded posts along the root has been reported to be homogenous but their retentive strength was found to be lower compared with those of parallel unthreaded or other kinds of threaded posts. The purpose of this in vitro study was to investigate the effect of length and diameter on the retentive strength of sandblasted tapered prefabricated titanium posts (Erlangen post system). Posts with constant taper angle but with three different lengths (9, 12, 15 mm) and apical diameters (0.5, 0.9, 1.1 mm) were cemented using zinc phosphate cement into the prepared and roughened post spaces of 90 intact anterior teeth. The post retention concerning length and diameter, being independent from each other, was measured by a tensile force test. The retentive strength was found to be proportional to the length as well as to the diameter of the posts. The mean minimum strength (181 +/- 14 N) recorded for the thinnest and shortest post was significantly lower than that of mean maximum strength (612 +/- 85 N) obtained from those of the thickest and longest post. Proportional bond strengths of the posts comprising their surface areas ranged between 6.8 and 7.9 N mm(-2) which were not significantly different between any group. The retention was effected strongly with the increase in the length (approximately 100%) than with the increase in the diameter (approximately 60%). Concerning the posts tested in this study, it is concluded that some caution should be exercised in the choice of post with appropriate length rather than diameter for the tooth concerned.  相似文献   
9.
The advantage of using ceramic inserts is to prevent major drawbacks of composite resins such as polymerization shrinkage, wear and microleakage. This in vitro study evaluated the marginal adaptation of two approximal ceramic insert systems after cementation to the cavities opened with ultrasonic tips. Proximal cavities with margins in enamel were prepared in 20 intact molars using ultrasonic tips (SONICSYS approx tips [microtorpedo size #2 and #3]; Siplus Instrument approximal [U-shaped]). Inserts of similar sizes (n=10) from two systems corresponding to the ultrasonic tips were placed in the cavities (SONICSYS Inlay; SDS-Inlay system), one on the mesial side and the other on the distal side of the same molar. Following cementation and thermocycling (5000 cycles, between 5-55 degrees C), cement thickness was measured at the buccal, lingual walls and pulpal floors of the proximal boxes under light microscope (x150). The mean cement thickness values recorded for SONICSYS inserts #2 (25 microm) was not significantly different (p>0.05) from that of SDS inserts of similar size (26 microm). There was a significant difference (p<0.05) in cement thickness values between SONICSYS #3 inserts (34 microm) and SDS inserts of similar size (23 microm). Comparison of mean values between the ceramic insert systems examined revealed that marginal adaptation was better at the buccal and lingual proximal walls than those at the pulpal floor in the SDS system, however, there was no difference for SONICSYS at both sizes. Ceramic inserts placed in cavities prepared with ultrasonic tips provide clinically acceptable marginal quality.  相似文献   
10.
OBJECTIVE: The aim of this study was to compare the effectiveness of the automated Interclean Interdental Plaque Remover with that of interdental brushes and Ultrafloss. METHOD AND MATERIALS: The interdental hygiene effectiveness of 35 healthy patients suffering from gingivitis was studied by an examiner daily over a period of 1 week. The sizes of the interdental spaces were classified and corresponding-sized interdental brushes or floss was selected. In a random, split-mouth design both interdental cleaning methods, mechanical and manual, were applied while the patients continued to use standard brushing techniques. Disclosed proximal plaque, the papillary bleeding index, and interdental bleeding tendency on stimulation were evaluated. RESULTS: The papillary bleeding index was reduced from an average value of 40% to 25%. Only 5% of interproximal plaque remained after manual interdental cleaning, whereas 40% of plaque was still present after use of the Interclean device. Cleaning efficiency of manual and mechanical methods was comparable in only 1 interproximal space size. At the end of the study, the interdental bleeding on stimulation was significantly higher in the automatically cleaned interspaces than in the manually cleaned spaces. CONCLUSION: Manual interproximal cleaning was more effective than the automated device.  相似文献   
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