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排序方式: 共有1906条查询结果,搜索用时 15 毫秒
41.
Serum magnesium concentrations in type 1 diabetic patients: relation to early atherosclerosis 总被引:1,自引:0,他引:1
Hypomagnesemia and sub-clinical atherosclerosis are common in type 1 diabetic patients, and are especially common in poorly controlled and chronically treated diabetics. The aim of this study was to evaluate the relationships between serum magnesium (Mg) and intima-media thickness (IMT), and functions of common carotid artery (CCA), accepted as markers of early carotid atherosclerosis in type 1 diabetic patients. Serum magnesium levels were measured in 51 diabetic patients (26 girls and 25 boys). Age, duration of diabetes as well as major cardiovascular risk factors, including anthropometric and metabolic parameters were matched between girls and boys. CCA structure and functions were measured by ultrasonography as IMT, cross-sectional compliance (CSC), cross-sectional distensibility (CSD), diastolic wall stress (DWS), and incremental elastic modulus (IEM). The difference for serum Mg was significant between diabetic girls and boys (0.75+/-0.09 mmol/l versus 0.86+/-0.14 mmol/l; p=0.02). Mg levels were correlated with IMT (r=-0.58, p=0.004) and DWS (r=-0.49, p=0.01) in girls and with IMT (r=-0.55, p=0.007) and DWS (r=-0.46, p=0.03) in boys. In a multivariate regression model, Mg, systolic blood pressure and waist-hip ratio emerged as independent correlates for mean IMT in girls with the total variance explained being 63%, and Mg and triglycerides emerged as independent correlates for mean IMT in boys with the total variance explained being 68%. Mg did not emerge as independent correlates for mean DWS in both girls and boys. Serum magnesium levels in children and adolescent patients with type 1 diabetes are associated with early atherosclerosis. 相似文献
42.
PURPOSE: To investigate the effects of alpha-1 adrenergic blockers on pupil diameter (PD) in rats. METHODS: Four groups, with 10 rats each, were designed to receive terazosin, tamsulosin, doxazosin, and no medication. Dilated pupil diameter (PD) measurements were performed 24 hr before, 24 hr after, and 30 days after the initiation of medication, and after 30 days of washout. The intergroup and intragroup differences in PD were evaluated using one-way ANOVA and Wilcoxon signed rank test, respectively. RESULTS: In day 1, PD decreased in both eyes significantly only in tamsulosin and doxazosin groups, but these effects became insignificant at 30 days of treatment (p > 0.05). The control group showed no significant difference in PD (p > 0.05). PD values returned to baseline after the washout period in all groups. CONCLUSIONS: A significant reduction in PD occurred in two of the three groups with alpha-1 adrenergic blockers (tamsulosin and doxazosin), but this effect was not sustained at 30 days. Further functional and structural studies of the iris are needed to determine the clinical significance of these findings. 相似文献
43.
Posterior iris fixation of the iris-claw intraocular lens implantation through a scleral tunnel incision 总被引:1,自引:0,他引:1
PURPOSE: To evaluate the technique, efficacy, and safety of posterior iris fixation of iris-claw intraocular lens (IOLs) implantation through a scleral tunnel incision for aphakia correction. DESIGN: Noncomparative, interventional case series. METHODS: A secondary posterior iris fixation of the Artisan iris-claw IOL (Ophthec BV, Groningen, The Netherlands) was implanted for aphakia correction in the authors' clinical practice. Uncorrected visual acuity, best spectacle-corrected visual acuity (BSCVA), astigmatism, manifest refraction, lens position, pigment dispersion, and intraocular pressure (IOP) were evaluated in 32 consecutive eyes of 32 patients. RESULTS: BSCVA was 20/40 or better in 28 eyes (87.50%) during the mean follow-up time (nine months). Mean postoperative spherical equivalent was -0.70 diopters (D; standard deviation [SD], 0.47 D) at six months after surgery. Mean prediction error was -0.13 D (SD, 0.28 D), and mean absolute prediction error was 0.26 D (SD, 0.15 D). Preoperative mean astigmatism was -1.08 D (SD, 0.55 D; range, 0.0 to -2.0 D). At six months after surgery, mean astigmatism was -2.1 D (SD, 0.81 D; range, -0.75 to -3.75 D). There was no significant postoperative IOP increase. Lens position, evaluated by Oculus Pentacam (Pentacam 70700: Oculus, Wetzlar, Germany) and ultrasound biomicroscopy [UBM] (Ophthalmic Technologies Inc, Toronto, Ontario, Canada), was parallel to the iris plane. CONCLUSIONS: Posterior iris fixation of the iris-claw IOL implantation through a scleral tunnel incision is a safe procedure and an effective option for aphakic eyes without capsule support. 相似文献
44.
45.
The risk of radiation-induced carcinogenesis after external beam radiotherapy of Graves' orbitopathy 总被引:3,自引:0,他引:3
PURPOSE: In order to estimate the risk of radiation-induced carcinogenesis after external beam radiotherapy of Graves' orbitopathy, we made dosimetric measurements with thermoluminescent dosimeters in a male Rando phantom using our treatment technique. METHODS: We produced dose-volume histograms from 5-mm CT slices using our treatment planning system. In this way we estimated the irradiation dose received by the main surrounding organs such as the brain, the bone and the eyeball. We use 6-MV X-ray for the treatment of Graves' orbitopathy and our total dose is 2,000 cGy, 200 cGy per fraction. Clinical target volume was limited to the retrobulbar orbital content and medial rectus muscle, sparing the lenses, lacrimal glands and the sella turcica. All dosimetric measurements with thermoluminescent dosimeters were made 3 times. RESULTS: We found that the dose to the right lens was 101.6 mGy and to left lens 103.4 mGy. Average absorbed doses to red bone marrow, thyroid, lung, esophagus, bone surface, skin and brain, respectively, were estimated to be 523, 21, 4, 5, 81, 29, 47 mGy. Then, using tissue weighting factors specified by the International Commission of Radiation Protection, the resulting total effective dose was calculated to be 66.8 mSv. CONCLUSION: The risk factor for fatal cancer development derived from human epidemiological data is presently assumed to be 10% per Gy. In patients treated by our method of retro-orbital external beam radiotherapy for Graves' orbitopathy, there is a 0.0067 (or 7 per 1,000 persons or 0.7%) risk of developing fatal radiation-induced cancer. 相似文献
46.
Cakan A Samancilar O Nart D Cagirici U 《Interactive Cardiovascular and Thoracic Surgery》2003,2(3):345-347
A 34-year-old woman presented with chest pain and a solitary pulmonary nodule on chest roentgenogram. She was diagnosed with a rare benign lung tumor, alveolar adenoma of the lung, through pathological examination of the surgical specimen resected from the left upper lobe. Clinicians should also keep this entity in mind when making the differential diagnosis of a solitary pulmonary nodule. 相似文献
47.
Yigit O Uslu Coskun B Coskun H Yilmaz B Alkan S Cinar U Dadas B 《The Laryngoscope》2004,114(9):1668-1673
HYPOTHESIS: This study was conducted to compare the effectiveness of two anti-adhesive barriers (Seprafilm and Interceed) for reducing adhesions after thyroidectomy in a rat model. The anti-adhesive barriers are suggested for use in repeated surgeries in general and the gynecologic fields in particular. STUDY DESIGN: Controlled, randomized study. METHODS: Twenty-eight male Wistar Albino rats that underwent right subtotal thyroidectomy were randomly assigned to three groups. One group received Seprafilm (n = 10), and the other received Interceed (n = 10) as anti-adhesive barriers. The third group was the control group (n = 8). At postoperative day 14, the rats were killed under general anesthesia, and the surgical fields were evaluated for the adhesion formation. The extent of the adhesion formation is scored from 0 (no adhesions) to 2 (fibrous adhesions that required sharp dissection). Histopathologically, chronic inflammation, histiocyte, fibroblast, fibrosis, collagen, vascularization, granuloma, giant cell, and fat necrosis were examined. RESULTS: All the subjects in the control group, 7 of 10 in the Interceed group, and 4 of 10 in the Seprafilm group needed to be dissected bluntly or sharply. There was significant difference between the Seprafilm and the control group (P < .05) whereas there was no significant difference between the Interceed group and the control group (P > .05). When examined histopathologically, the criteria showing adhesion, such as fibrosis, fibroblast, and collagen were higher in the control group compared with the Seprafilm and Interceed groups. There was no significant difference between the Seprafilm and Interceed groups, whereas a significant difference was found between these two groups and the control group. CONCLUSION: This study suggests that both Seprafilm and Interceed decrease the incidence of posthyroidectomy adhesions in a rat model. Both agents showed no foreign body reaction. 相似文献
48.
OBJECTIVE: The purpose of this study was to evaluate the risk factors involved in failed vaginal hysterectomies. METHODS: Data on all vaginal hysterectomies performed by a single gynecologic surgeon were collected prospectively. Patients requiring pelvic floor repair were excluded. Any procedure converted to the abdominal approach was classified as a failed vaginal hysterectomy and comprised the study group. For every woman who had a failed vaginal hysterectomy, the next 2 women who had successful vaginal hysterectomies immediately after the failed vaginal hysterectomy were taken as controls. Risk factors such as age, parity, body weight, surgical indication, uterine size, presence of leiomyomata in the anterior lower uterine segment, previous pelvic surgeries, abdominopelvic adhesions, location and length of cervix, narrow pubic arch, intraoperative complications such as bleeding requiring transfusion, visceral injury, nulliparity, and adnexal removal were compared between groups. RESULTS: We compared 25 failed vaginal hysterectomies with 50 controls whose procedures were completed successfully through the vagina. Among all the factors gynecologists can assess preoperatively, only the presence of a narrow pubic arch increased the risk of failure for vaginal hysterectomy (odds ratio [OR] 4.1; 95% confidence interval 1.32-12.69). Intraoperative bleeding with transfusion was also found as an independent cause for conversion to laparotomy (OR 7.37; 95% confidence interval 1.75-31.06). CONCLUSION: Women with a narrow pubic arch are not good candidates for vaginal hysterectomy. The most common unpredictable cause for conversion to laparotomy from the vaginal approach is intraoperative bleeding requiring transfusion. LEVEL OF EVIDENCE: II-2 相似文献
49.
Ozen S Anton J Arisoy N Bakkaloglu A Besbas N Brogan P García-Consuegra J Dolezalova P Dressler F Duzova A Ferriani VP Hilário MO Ibáñez-Rubio M Kasapcopur O Kuis W Lehman TJ Nemcova D Nielsen S Oliveira SK Schikler K Sztajnbok F Terreri MT Zulian F Woo P 《The Journal of pediatrics》2004,145(4):517-522
OBJECTIVE: To characterize pediatric patients who had been diagnosed with polyarteritis nodosa (PAN) through necrotizing vasculitis of the small and mid-size arteries or those with characteristic findings on angiograms data were collected. STUDY DESIGN: Pediatricians were asked to classify their patients into one of the four suggested groups for juvenile PAN. Twenty-one pediatric centers worldwide participated with 110 patients. RESULTS: The girl:boy ratio was 56:54, with a mean age of 9.05 +/- 3.57 years. The cases were classified as: 33 (30%) cutaneous PAN; 5 (4.6%) classic PAN associated with hepatitis B surface antigen (HBs Ag); 9 (8.1%) microscopic polyarteritis of adults associated with antineutrophil cytoplasmic antibodies (ANCA); and 63 (57.2%) systemic PAN. Cutaneous PAN was disease confined to the skin and musculoskeletal system. All patients with HBs Ag-associated classic PAN were diagnosed with renal angiograms. Antiviral treatment was administered in most cases. Microscopic PAN patients had pulmonary-renal disease, in combination or separately. ANCA was present in 87%, and 2 patients progressed to end-stage renal failure. Patients classified with systemic PAN had multiple system involvement, almost all had constitutional symptoms, and all had elevated acute phase reactants. Corticosteroids and cyclophosphamide were the first choices of immunosuppressive treatment. The overall mortality was 1.1%. CONCLUSIONS: There were remarkable differences among pediatric patients with PAN, with different clinical manifestations and overall better survival and lower relapse rates when compared with adults. 相似文献
50.
Morphometry of the anterior third ventricle region as a guide for the transcallosal-interforniceal approach 总被引:1,自引:0,他引:1
Erturk M Kayalioglu G Ozer MA Ozgur T 《Neurologia medico-chirurgica》2004,44(6):288-92; discussion 292-3
The transcallosal-interforniceal approach is the most appropriate approach to localize and totally remove space-occupying lesions around the anterior third ventricle region such as craniopharyngiomas and gliomas. This study examined the microsurgical anatomy of the normal anterior third ventricle region in 81 adult cadaver hemispheres. The central sulcus was identified and surface landmarks determined as the points 5 cm (P5) and 7 cm anterior to the central sulcus (P7). The distances between P5 and P7 and the upper margin of the interventricular foramen, which delineate the surgical corridor chosen to avoid disturbance of important neural structures, were 46.26-60.96 (54.09 +/- 3.35) mm and 48.00-62.00 (54.94 +/- 3.09) mm, respectively. The distances between the upper margin of the hemisphere and the cingulate sulcus, especially important for avoiding damage to the cingulate gyrus and other mesiolimbic structures, were 13.54-30.00 (21.28 +/- 3.89) mm and 12.22-29.52 (21.12 +/- 3.90) mm at the level of P5 and P7. The distances between the upper margin of the hemisphere and the callosal cistern containing the pericallosal artery were 28.34-40.50 (33.94 +/- 2.84) mm and 28.16-40.26 (33.50 +/- 2.61) mm, respectively. Normative morphometric data of the structures involved in the surgical procedure are necessary for planning and performance of the transcallosal-interforniceal approaches. This study of a large series of specimens shows that these measurements have large individual variations. 相似文献