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排序方式: 共有428条查询结果,搜索用时 15 毫秒
1.
Correlation between penile angiography and duplex scanning of cavernous arteries in impotent men 总被引:1,自引:0,他引:1
During the diagnostic evaluation of patients with vasculogenic impotence duplex scanning has been proposed as a reliable noninvasive method to evaluate the cavernous arteries. However, the sensitivity and specificity of this test have never been elucidated. To provide insight into the clinical value of this test 25 men who presented with impotence and failed to respond to 60 mg. intracavernous papaverine were evaluated with duplex scanning and the results of this modality were compared to penile angiography. The cavernous arteries were considered normal by duplex scanning if the artery demonstrated either a 60% or greater increase in diameter and/or a peak flow velocity of greater than 25 cm. per second 5 minutes after papaverine injection. Penile angiography was considered normal if both cavernous arteries were visualized and appeared to be normal radiographically (after intracorporeal papaverine). In the 25 patients studied there was no significant difference in peak flow velocity between patients with normal or abnormal cavernous arteries by angiography. In addition, arterial dilatation (more than 60%) after papaverine injection did not correlate with the results of the angiogram. These data demonstrate that duplex scanning of the cavernous arteries does not correlate well with what is observed by penile angiography in a selected population of men with vasculogenic erectile dysfunction. Since penile angiography itself has limitations in the evaluation of the penile arteries, the reliability of duplex scanning to identify cavernous artery dysfunction needs additional confirmation. 相似文献
2.
Several weeks after porcine retinal pigment epithelial (RPE) cell cultures attain confluence, macroscopically visible brown foci appear. The cuboidal cells that form the foci contain numerous phase dark granules that do not exhibit the autofluorescence characteristic of lipofuscin. The data described here indicate that the granules are melanosomes. Electron microscopy revealed three types of electron-dense granules in these cells: simple spheres 0.3-0.5 microns in diameter, large spheres 1-2 microns in diameter, and lysosomal aggregations of the smaller spheres. The matrix of both spheres is composed of 40-nm microvesicles that were also found free in the cytoplasm and aggregated within vacuolar structures. Reversed-phase high-performance liquid chromatography of RPE cells and their media detected melanogens, i.e. intermediates of melanin biosynthesis, including several indole derivatives. The porcine RPE cultures therefore may be a useful system for studying melanogenic regulation. 相似文献
3.
M H Kody J M Kabo K L Markolf F J Dorey H C Amstutz 《Clinical orthopaedics and related research》1990,(257):146-153
This study was conducted to determine the effects of design on the initial fixation of several types of screw-ring acetabular components. The components were tested in polyurethane foam to assess relative screw fixation strengths with a consistent material. Embalmed pelves from anatomic specimens were used to conduct paired tests between designs that showed large differences in insertional torque to failure in foam. The quality of the initial fixation in foam was found to be dependent on the design features of the components. Components with widely spaced, deep threads, and minimal thread interruptions offered the strongest initial fixation in foam. Tests in bone revealed a wide range of fixation strengths reflecting the variability in bone quality. No differences in fixation strength attributable to component design were observed in bone. When the insertional failure torque was greater than 60 N.m, one-half of the pelves fractured, and these fractures occurred with all designs. At failure torques less than 60 N.m, failure was predominantly due to thread strippage of the screw, with only two of 20 specimens experiencing pelvic fracture. 相似文献
4.
L B Davlin H C Amstutz S M Tooke F J Dorey S Nasser 《The Journal of bone and joint surgery. American volume》1990,72(7):1035-1042
Seventy-four cemented conventional total hip arthroplasties (in fifty-five patients) and thirty-seven cemented surface replacements (in thirty-two patients) were done between 1971 and 1984 for treatment of osteoarthrosis secondary to congenital dislocation of the hip. The patients in the first group were older and had more severe dysplasia. In all patients, we tried to position the acetabular component at the level of the true acetabulum. In both groups, the operation relieved pain and improved the function of the hip in the short term. There were fewer and less severe early postoperative complications in the surface-replacement group, but the rate of long-term failure (revision or resection) was substantially higher. Survivorship analysis demonstrated that neither type of operation yielded durable results in younger patients; all revisions were in patients who were less than sixty years old. However, in older patients who had cemented conventional total hip arthroplasty, survivorship was excellent, regardless of the amount of dysplasia. 相似文献
5.
Dopa and oxygen inhibit proliferation of retinal pigment epithelial cells, fibroblasts and endothelial cells in vitro 总被引:1,自引:0,他引:1
Some quinones catalyze superoxide formation in a futile cycle involving electron transfer to molecular oxygen. If the quinolic precursors of melanin participated in the futile cycle, the high ambient oxygen surrounding postnatal RPE would make continued melanogenesis risk for the retina. To probe the possibility that arrest of melanogenesis in postnatal RPE is a protective mechanism, we assayed the growth rates of RPE cells, aortic endothelial cells and skin fibroblasts exposed to 0, 10, 50, 100 and 250 microM dopa. To assess the contribution of the futile cycle, we studied the effects of oxygen concentration and the antioxidants, superoxide dismutase and catalase. We found that all three cell types were significantly and dose-dependently inhibited by dopa and that the effects of dopa were oxygen dependent. The powerful inhibition of RPE cells by dopa was counteracted by inclusion of superoxide dismutase and catalase, but not by an inhibitor of dopa oxidase (phenylthiourea), indicating that the mechanism of growth suppression did not involve melanogenesis but, rather, dopa-dependent formation of superoxide in the media. Endothelial cells were more sensitive to the dopa-mediated oxidative damage than were RPE cells or fibroblasts. Fibroblasts were most affected by oxygen alone, and least affected by dopa. These data suggest that suppression of melanogenesis in the postnatal RPE may be an important mechanism for preventing oxidative damage to the retina and the choriocapillaris We propose that the generation of oxygen radicals by the quinone futile cycle is a viable model of the damage of cells in culture by dopa. 相似文献
6.
Randomised controlled trial of pelvic floor muscle exercises and manometric biofeedback for erectile dysfunction. 总被引:1,自引:0,他引:1 下载免费PDF全文
Grace Dorey Mark Speakman Roger Feneley Annette Swinkels Christopher Dunn Paul Ewings 《The British journal of general practice》2004,54(508):819-825
BACKGROUND: The pelvic floor muscles are active in normal erectile function. Therefore, it was hypothesised that weak pelvic floor muscles could be a cause of erectile dysfunction.AIMS: To compare the efficacy of pelvic floor muscle exercises and manometric biofeedback with lifestyle changes for men with erectile dysfunction.Design of study: Randomised controlled trial.SETTING: The Somerset Nuffield Hospital, Taunton, United Kingdom.METHOD: Fifty-five men with erectile dysfunction (median age 59.2 years; range 22-78 years) were enrolled from a local urology clinic. Of these, 28 participants were randomised to an intervention group and engaged in pelvic floor exercises, as well as receiving biofeedback and suggestions for lifestyle changes. Twenty-seven controls were solely advised on lifestyle changes. Baseline, 3- and 6-month assessments were: erectile function domain of International Index of Erectile Function (IIEF), Partner's International Index of Erectile Function (PIIEF), Erectile Dysfunction-Effect on Quality of Life (ED-EQoL), anal manometry, digital anal measurements, and clinical assessment by an assessor blind to treatment allocation. After 3 months, the control group were transferred to the active arm.RESULTS: At 3 months, compared with controls, men in the intervention group showed significant mean increases in the erectile function domain of the IIEF (6.74 points, P = 0.004); anal pressure (44.16 cmH(2)O, P <0.001); and digital anal grades (1.5 grades, P <0.001). All showed further improvement in these outcomes at 6 months. Similar benefits were seen in men of the control arm after transfer to active treatment. A total of 22 (40.0%) participants attained normal function, 19 (34.5%) participants had improved erectile function, and 14 (25.5%) participants failed to improve.CONCLUSION: Pelvic floor muscle exercises and biofeedback are an effective treatment for men with erectile dysfunction. 相似文献
7.
Long-term effects of finasteride on prostate tissue composition 总被引:11,自引:0,他引:11
Marks LS Partin AW Dorey FJ Gormley GJ Epstein JI Garris JB Macairan ML Shery ED Santos PB Stoner E deKernion JB 《Urology》1999,53(3):574-580
OBJECTIVES: To determine the long-term effects of finasteride treatment on prostate tissue composition; to relate these effects to clinical outcomes; and to test the hypothesis that finasteride exerts a selective or preferential action on the transition zone. METHODS: Nineteen men with symptomatic benign prostatic hyperplasia (BPH) who completed a 6-month double-blind trial of finasteride were enrolled in a 24-month open-label extension study of drug responders. Magnetic resonance imaging and prostate biopsy for morphometric analysis were performed together 70 times: at baseline (n = 19), after treatment periods of intermediate duration (6 to 18 months, n = 32), and after long-term drug treatment (24 to 30 months, n = 19). At baseline, prostate volume averaged 51 cc, of which 57% was transition zone. RESULTS: Decreases in symptom score, dihydrotestosterone and prostate-specific antigen levels, and prostate volume occurred at 6 months (P <0.01), stabilized, and were maintained without further long-term decreases. Prostate epithelium contracted progressively from baseline (19.2% tissue composition; 6.0-cc volume; 3.2 stroma/epithelial ratio) to intermediate (12.5%, 3.3 cc, and 5.6, respectively) to long-term treatment (6.4%, 2.0 cc, and 17.4, respectively, P <0.01 for all). Percent epithelial contraction was similar in the peripheral and transition zones (P = NS). The transition zone remained a relatively constant proportion (53% to 58%) of whole-prostate volume from baseline to long-term observation. CONCLUSIONS: Long-term finasteride treatment (24 to 30 months) results in a marked involution of the prostate epithelium, which continues to progress for many months after clinical effects stabilize. The effect on the epithelium is similar in the peripheral and transition zones for both morphometric and volumetric changes. Progressive contraction of the prostate epithelium appears to constitute the underlying mechanism for sustained action of finasteride. 相似文献
8.
STUDY DESIGN: An outcomes assessment of 14 elite college athletes who had undergone lumbar disc surgery was performed using the SF-36, a validated questionnaire that assesses quality of life. OBJECTIVES: To determine the outcomes and results of lumbar disc surgery in an elite group of athletes and compare the results with those in the general population and in age-matched control subjects. SUMMARY OF BACKGROUND DATA: Lumbar disc surgery is reported to be a highly successful procedure with excellent results. The outcome in elite athletes has not been assessed and compared with population norms and age-matched control subjects. METHODS: Fourteen athletes from schools in the National Collegiate Athletic Association with a mean age of 20.7, underwent lumbar discectomy for radiculopathy refractory to conservative treatment. Ten had a single-level microdiscectomy, three a two-level microdiscectomy, and one a percutaneous discectomy. Patients were evaluated at a mean follow-up of 3.1 years, underwent a detailed clinical evaluation, and filled out the SF-36 questionnaire. RESULTS: All 14 patients had improvement of pain with elimination of the radicular component, took less medication than before surgery, and returned to recreational sports. Nine patients, all with a single level microdiscectomy, returned to varsity sports. Five athletes prematurely retired from competitive sports because of continued symptoms. Three of the athletes who retired underwent two-level procedures, and one had a percutaneous discectomy. SF-36 scores for bodily pain, physical role, and social and mental health roles were significantly lower in those athletes who retired. Patient scores were also compared with those in a group of noninjured age-and sport-matched college athletes. There were no differences between injured and noninjured athletes, but both groups had scores significantly lower than normal values in an age-matched group for bodily pain, physical role, general health, and social function. CONCLUSIONS: All patients were satisfied with their surgeries, were greatly improved, and were pain free in activities of daily living. For a single-level microdiscectomy, the success rate in elite athletes is excellent, with 90% of athletes able to return to a high level of competition. Two-level disease may be associated with a less favorable outcome. 相似文献
9.
Double-stem silicone implants have been used to reconstruct destroyed hallux metatarsophalangeal joints (MTPJ) for many years. When smaller implants became available, they were used to reconstruct the lateral four MTPJ. An arthroplasty of all MTPJ was performed using these implants in 44 patients (72 feet) with rheumatoid arthritis (RA). The mean age of patients was 46 years (range, 21 to 66) and 84% were female. Previous surgery had been performed on 28% of the feet. All patients were followed prospectively for an average of 67 months (range, 36 to 111). The patients were evaluated clinically and radiographically; results were recorded on a standardized foot form that allowed computer analysis of the data. The results showed improvement in the hallux valgus angle from 41.6 degrees to 16.1 degrees postoperatively, with no loss of correction over time. Similarly, other forefoot deformities, such as plantar callus and lateral toe abnormalities, all improved both clinically and radiographically. The pain, walking, and function scores all improved, with the greatest improvement being pain relief. Radiographic analysis showed some evidence of fracture in seven hallux (9.7%) and nine lateral toe (3%) implants. Only three toes with implant fracture had some pain at follow-up examination. Three other lateral toe implants were removed for pain. There was no evidence of deep infection or silicone synovitis. Other complications included superficial infection, delayed wound healing, and second surgery for heterotopic bone excision.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
10.
Pulmonary responses to exercise in pregnancy 总被引:1,自引:0,他引:1
R Artal R Wiswell Y Romem F Dorey 《American journal of obstetrics and gynecology》1986,154(2):378-383
The pulmonary responses of 88 pregnant women were compared to those of 39 nonpregnant control subjects during different exercise intensities. At rest the pregnant women had higher tidal volumes, oxygen consumption, carbon dioxide production, and respiratory exchange ratio. With increased work loads the pregnant volunteers have consistently lagged behind the nonpregnant control subjects for every parameter, which indicates a decrease in pulmonary reserve and inability to exercise anaerobically. 相似文献