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排序方式: 共有2194条查询结果,搜索用时 31 毫秒
1.
Vidya P Kulkarni Kaiwen Lin Selim R Benbadis 《Journal of clinical neurophysiology》2007,24(6):433-437
The definition of the persistent vegetative state (PVS) is relatively straightforward, but its diagnosis can be challenging. We reviewed a series of EEG performed in patients with PVS to assess the diagnostic value of EEG. We reviewed records of all hospital patients with a diagnosis of persistent vegetative PVS. EEG findings included normal, continuous generalized slowing, intermittent generalized slowing, background slowing, background suppression, alpha, generalized periodic pattern, PLEDS, and triphasic waves. EEG findings had no association with etiology and varied from one pattern to another in the same patients' EEGs obtained at different times (see table). We conclude that EEG findings in PVS are heterogeneous and too variable to be of diagnostic value. 相似文献
2.
3.
Selim Orgül George A. Croffi E. Michael Van Buskirk 《Albrecht von Graefes Archiv fur klinische und experimentelle Ophthalmologie》1997,235(2):82-86
Background: The influence of the contour line alignment software algorithm on the variability of the Heidelberg Retina Tomograph (HRT) parameters remains unclear. Methods: Nine discrete topographic images were acquired with the HRT from the right eye in six healthy, emmetropic subjects. The variability of topometric data obtained from the same topographic image, analyzed within different samples of images, was evaluated. A total of four mean topographic images was computed for each subject from: all nine discrete images (A), the first six of those images (B), the last six of those nine images (C), and the first three combined with the last three images (D). A contour line was computed on the mean topographic image generated from the nine discrete topographic images (A). This contour line was then applied to the three other mean topographic images (B, C, and D), using the contour line alignment in the HRT software. Subsequently, the contour line on the mean topographic images was applied to each of the discrete members of the particular images subsets used to compute the mean topographic image, and the topometric data for these discrete topographic images was computed successively for each subset. Prior to processing each subset, the contour line on the discrete topographic images was deleted. This strategy provided a total of three analyses on each discrete topographic image: as a member of the nine images (mean topographic image A), and as a member of two subsets of images (mean topographic image B, C, and/or D). The coefficient of variation (100×SD/mean) of the topographic parameters within those three analyses was calculated for each discrete topographic image in each subject (intraimage coefficient of variation). In addition, a coefficient of variation between the nine discrete topographic images (interimage coefficient of variation) was calculated. Results: The intraimage and interimage variability for the various topographic parameters ranged between 0.03% and 3.10% and between 0.03% and 24.07% respectively. The intraimage coefficients of variation and interimage coefficients of variation correlated significant (r
2=0.77;P<0.0001). Conclusion: A high intraimage variability, i.e. a high variability in contour line alignment between sequential images, might be an important source of test re-test variability between sequential images. 相似文献
4.
Deniz Micozkadio?lu Murat Unal Yavuz Selim Pata Mine Ba?türk Leyla Cinel 《Medical science monitor》2008,14(6):CR299-CR304
BACKGROUND: The molecular mechanisms in malignant transformation of laryngeal mucosa are unknown; many clinical and pathological factors affect prognosis. We investigated a possible correlation between overexpression of p53, proliferating cell nuclear antigen (PCNA), and c-erbB-2, and the clinicopathologic features of laryngeal squamous cell carcinoma (SCC) and clarify their prognostic value. MATERIAL/METHODS: Thirty-three men with laryngeal SCC participated; all underwent primary surgery or surgery plus radiotherapy between 1999 and 2004 at our department. Paraffin sections of laryngeal SCC were immunohistochemically stained for p53, PCNA, and c-erbB-2. RESULTS: Overall, p53 overexpression was found in 16 patients. There was no relation between p53 immunohistochemical staining and tumor region. PCNA immunostaining was significantly stronger in supraglottic tumors compared with glottic tumors. Immunostaining of c-erbB-2 was not different in either location. There was no relation between the T stage of the tumor and p53 and c-erbB-2 immunostaining. However, there was a statistically significant positive correlation between the PCNA staining and T stage (stronger staining was present in T3 and T4 stages than in T1 and T2 stages). CONCLUSIONS: We could not find a statistically significant correlation between p53, PCNA, and c-erbB-2 and lymph node status, histologic differentiation, and survival rate. We demonstrated only a statistically significant positive correlation between PCNA staining and T stage. These data suggest that overexpression of p53, PCNA, and c-erbB-2 is not prognostic in laryngeal SCC. 相似文献
5.
Ilkay Koray Bayrak Zafer Ozmen Mehmet Selim Nural Murat Danaci Baris Diren 《Korean journal of radiology》2008,9(3):250-257
OBJECTIVE: It has been advocated that a reduced injection volume with highly concentrated (1 M) contrast material can produce a sharper bolus peak and an increased intravascular first-pass gadolinium concentration when compared with the use of a lower concentration (0.5 M). A higher concentration would also cause a reduction in dose. The purpose of our study was to test the use of a low dose (0.05 mmol/kg) of gadobutrol in magnetic resonance renography and angiography and compare the findings with a dose of 0.1 mmol/kg. MATERIALS AND METHODS: One-hundred-thirty-four patients referred for magnetic resonance angiography for suspected renovascular disease participated in the study. Contrast enhanced MR renography and angiography were performed after administration of a bolus of 0.1 mmol/kg or 0.05 mmol/kg gadobutrol in randomized patients. The relative signal intensity-time curves of the aorta, peripheral cortex and parenchyma, were obtained. Two radiologists evaluated the angiographic images and evaluated the quality of angiography. RESULTS: The signal intensity with a low dose of gadobutrol was significantly lower in early phases, in the peripheral cortex (for 36, 54, 72 and 90 seconds), the parenchyma (for 36, 54, 72 seconds) and the aorta (for 18, 36, 54, 72 seconds). The decreases in the early phase obtained with a low dose of gadobutrol caused blunter time intensity curves. The difference in the quality scores of the readers for the angiographic images for the use of the two different doses was not statistically significant (p > 0.05). CONCLUSION: A lower dose of gadobutrol can be used for MR renal angiography, but for MR renography the normal dose should be used. 相似文献
6.
Birol Civelek H. İbrahim Inal Kubilay Ozdil Selim Celebioglu 《European journal of plastic surgery》2007,30(1):25-28
Skin is the most commonly used tissue for the transplantation. A meticulous care of the donor site is needed to prevent scarring,
delayed healing, and pain. Various agents and dressing materials have been reported to help healing of skin graft donor sites.
Sucralfate is an extensively used agent, which provides acute gastroprotection and acceleration of chronic ulcer healing.
In this study, we assessed the effects of topical sucralfate on the healing of the split thickness skin graft donor sites
in a prospective comparative way. The study was carried out on 32 randomly chosen patients undergoing surgery for various
causes and requiring split thickness skin graft resurfacing. The upper halves of the skin graft donor sites on the thighs
were simply covered with paraffin gauze and the lower half was covered with sucralfate-soaked paraffin gauzes. The day of
full epithelization varied from 6 to 9 days and 8–12 days on the sucralfate-applied areas and on the control sites, respectively.
The mean value of the healing was 7.01 days in the studied lower halves and 10.8 days in the upper halves. The healing rate
was strikingly faster and less painful on the sucralfate-applied areas. We were able to discharge patients earlier than usual,
and patients’ comfort increased. It seems that sucralfate is a promising topical agent to increase the healing rate and decrease
the incidence of associated problems such as pain and hypertrophic scar. 相似文献
7.
Chlamydia conjuctivitis results from infection by chlamydia trachomatis, the commonest treatable sexually transmitted infection in Europe. Its clinical manifestations involve the conjunctiva and the cornea. The inflammation under the upper eyelid may be sufficient to present as ptosis, however previously it has not been documented to cause a preseptal cellulitis. We present such a case. A 15-year-old girl was diagnosed with a left viral conjunctivitis. Five days later, she returned with marked oedema of the left upper and lower lids accompanied by erythema. The tarsal conjunctiva revealed follicles and large papillae and extra ocular movements revealed discomfort on elevation. A secondary diagnosis of bacterial pre septal cellulitis was made and the treatment was changed a broad spectrum oral antibiotic. On review at two days, the patient now complained of a large amount of purulent discharge in association with the marked pre septal swelling. As previous bacteriology and virology had been negative, the patient was re swabbed for chlamydia. This proved positive and her symptoms completely resolved following administration of Azithromycin. In this particular case recognition of the pathogen is important to alert the patient to the likelihood of unknown genital infestation. In all cases of positive culture, the patient should be counselled to attend a genitourinary clinic and to alert any sexual partners to the need to do likewise. 相似文献
8.
Selcen Yuksel Selim Ayhan Vugar Nabiyev Montse Domingo-Sabat Alba Vila-Casademunt Ibrahim Obeid Francisco Sanchez Perez-Grueso Emre Acaroglu 《The spine journal》2019,19(1):71-78
BACKGROUND CONTEXT
Health-related quality of life (HRQOL) parameters have been shown to be reliable and valid in patients with adult spinal deformity (ASD). Minimum clinically important difference (MCID) has become increasingly important to clinicians in evaluating patients with a threshold of improvement that is clinically relevant.PURPOSE
To calculate MCID and minimum detectable change (MDC) values of total scores of the Core Outcome Measures Index (COMI), Oswestry Disability Index (ODI), Physical Component Summary (PCS), Mental Component Summary (MCS) of the Short Form 36 (SF-36), and Scoliosis Research Society 22R (SRS-22R) in surgically and nonsurgically treated ASD patients who have completed an anchor question at pretreatment and 1-year follow-up.STUDY DESIGN/SETTING
Prospective cohort.PATIENT SAMPLE
Surgical and nonsurgical patients from a multicenter ASD database.OUTCOME MEASURES
Self-reported HRQOL measures (COMI, ODI, SF-36, SRS-22R, and anchor question).METHODS
A total of 185 surgical and 86 nonsurgical patients from a multicenter ASD database who completed pretreatment and 1-year follow-up HRQOL scales and the anchor question at the first year follow-up were included. The anchor question was used to determine MCID for each HRQOL measure. MCIDs were calculated by an anchor-based method using latent class analysis (LCA) and MDCs by a distribution-based method.RESULTS
All differences between means of baseline and first year postoperative total score measures for all scales demonstrated statistically significant improvements in the overall population as well as the surgically treated patients but not in the nonsurgical group. The calculated MDC and MCID values of HRQOL parameters in the entire study population were 1.34 and 2.62 for COMI, 10.65 and 14.31 for ODI, 6.09 and 7.33 for SF-36 PCS, 6.14 and 4.37 for SF-36 MCS, and 0.42 and 0.71 for SRS-22R. The calculated MCID values for surgical and non-surgical treatment groups were 2.76 versus 1.20 for COMI, 14.96 versus 2.45 for ODI, 7.83 versus 2.15 for SF-36 PCS, 5.14 versus 2.03 for SF-36 MCS, and 0.94 versus 0.11 for SRS-22R; the MDC values for surgical and nonsurgical treatment groups were 1.22 versus 1.51 for COMI, 10.27 versus 9.45 for ODI, 5.16 versus 6.77 for SF-36 PCS, 6.05 versus 5.67 for SF-36 MCS, and 0.38 versus 0.43 for SRS-22R.CONCLUSIONS
This study has demonstrated that MCID calculations for the HRQOL scales in ASD using LCA yield values comparable to other studies that had used different methodologies. The most important finding was the significantly different MCIDs for COMI, ODI, SF-36 PCS and SRS-22 in the surgically and nonsurgically treated cohorts. This finding suggests that a universal MCID value, inherent to a specific HRQOL for an entire cohort of ASD may not exist. Use of different MCIDs for surgical and nonsurgical patients may be warranted. 相似文献9.
Lead causes male reproductive impairment among painters, but information is still limited. Therefore, the effect of lead on semen quality and reproductive endocrinal function in those patients was investigated. A case series of 27 infertile painters were subjected to semen analysis, measuring of blood lead level (PbB) and serum levels of endocrinal parameters including follicle‐stimulating hormone (FSH), luteinising hormone (LH), testosterone (T) and prolactin (PRL). Significantly lower sperm count and motility were found in those with duration of exposure (≥15 years), but no significant difference was found for PbB and serum levels of FSH, LH, PRL and T. A significant negative correlation between PbB and spermatic count and motility was observed, while there was no significant correlation between PbB and all endocrinal parameters. Patients with PbB ≥ 20 μg dl?1 showed a significant decrease in sperm motility and increase in testosterone alone among all measured hormones. But the observed decrease in sperm count did not reach a significant level. It is concluded that infertile painters are at risk of lead‐related influence on semen quality, especially sperm motility and increased testosterone level without significant affection of other reproductive endocrinal parameters. 相似文献
10.
Serdar Akgun Atike Tekeli Ozlem Kurtkaya Ali Civelek Selim C Isbir Koray Ak Sinan Arsan Aydin Sav 《European journal of cardio-thoracic surgery》2004,25(1):105-110
OBJECTIVE: In our experimental study, we aimed to test the effect of FK506, azathioprine and L-carnitine on protection of spinal cord injury due to ischemia-reperfusion. METHODS: Twenty-seven Sprague-Dawley male rats were randomly divided into five groups. They were subjected to spinal cord ischemia by clamping the abdominal aorta for 45 min. Thirty minutes before the aortic clamping, group I received 0.5 mg/kg FK506, group II received 100 mg/kg L-carnitine, group III received 4 mg/kg azathioprine, the fourth group was the control group and received only normal saline injection intravenously and the last group was the sham group. Neurological status was scored by using the Tarlov scoring system. Sections of the lumbar cord were harvested for histopathological grades (1-4), having regard to percentage of the apoptotic cells. RESULTS: Hind-limb motor function had recovered normally 48 h after the operation in all rats which received FK506, azathioprine and L-carnitine prophylactically. In contrast, all rats in the control group had deteriorated to paraplegia by 48 h after the operation (P<0.05). Histopathologic sections in the involved spinal cord segment showed that a greater number of motor neuron cells were preserved and there were less apoptotic cells in the rats that received FK506, azathioprine and L-carnitine than those in control group. CONCLUSIONS: These results suggest that prophylactic use of FK506, azathioprine and L-carnitine protects motor neuron cells from ischemic spinal cord injury. 相似文献