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991.
The objective of this study was to evaluate the efficacy of various diagnostic modalities in the assessment of patients with massive lower gastrointestinal bleeding. The charts of all patients admitted to a McGill University affiliated teaching hospital with the diagnosis of lower gastrointestinal bleeding over a 25-year period were reviewed. There were 136 patients who underwent 202 admissions. The information documented included demographics on age, gender, co-morbid disease, prescribed medications, requirements for blood transfusions, orthostatic change in blood pressure, acute drop in hematocrit (to <30%), and exclusion of upper gastrointestinal bleeding. Among the 202 admitted patients there were 116 men and 86 women), with an average age of 70 years (range 16-95 years). At least one significant medical disease was found in 93% of these patients; and 20% were on aspirin and 5% on anticoagulants at the time of diagnosis. Rigid or flexible sigmoidoscopy was performed in 68 and 18 patients, respectively, with a definitive diagnosis made in 2.9% and 11.0%, respectively. Colonoscopy was performed in 152 cases, 20 of which were incomplete; a specific diagnosis was made for 59 admissions (45%). A red blood cell or colloid scan was performed on 53 patients, with extravasation noted in 13 (24.5%); a localized site of bleeding was identified in 9 cases (17%). Angiography was performed on 31 patients with bleeding sites localized in 6 (19%). Barium enemas were completed in 85 of 92 patients, and the presumptive cause of bleeding was identified in 72% of those with a complete examination. The most common causes identified were diverticulosis in 52 patients and angiodysplasia in 14. The cause of bleeding was not detected in 48 (35%). Bleeding stopped in most patients spontaneously, with only 7 requiring operation. The average number of units transfused was 3 (range 0-26). Scintigraphy and angiography were less efficacious than colonoscopy for localizing the site and etiology of the bleeding. Despite the combination of investigative modalities, a definitive diagnosis was not made in 35% of the admitted patients. The need for operative intervention in our study was lower than in most previous reports. 相似文献
992.
Al Shurafa H Wali S Chehab MS Al Shahed M Jawdat M Djurberg H Bassas A 《Clinical transplantation》2002,16(3):222-226
OBJECTIVE: To analyse the outcome of six children with Crigler-Najjar syndrome type I (CNS-I) and report the first three living-related liver transplants for this syndrome in Saudi Arabia and the Middle East. SETTINGS: To review the medical records of six children suffering from CNS-I, three of whom underwent living-related liver transplantation (LRLT) between 22 November 1998 and January 2001. MAIN RESULTS: Living-related liver transplantation was performed in three children with a pre-transplant unconjugated bilirubin level of 362, 381 and 502 micromol/L, respectively, despite daily phototherapy of >or= 12 h. Two of the transplanted children developed acute hepatocellular rejection, which was successfully treated with methylprednisolone pulse therapy. One tested cytomegalovirus positive (using the PP65 method), but showed no signs of clinical infection and was treated with ganciclovir. One patient had a biliary leak at the cut surface of the graft which was surgically repaired. Post-operative bilirubin levels returned to normal in all three transplanted children and no further phototherapy was required. One patient, who was not transplanted but received phototherapy, developed severe neurological damage prior to the start of our living-related liver transplant programme with a bilirubin level of 450 micromol/L, her sister is still awaiting transplantation. A 14-yr-old child with a bilirubin level of 420 micromol/L is presently undergoing phototherapy whilst awaiting orthotopic liver transplantation because of the lack of a suitable living-related donor. Six siblings of the six children in our series were reported dead by the families. CONCLUSION: Crigler-Najjar syndrome type I is a relatively common disease in Saudi Arabia for which LRLT is a curative treatment when performed at an early age before the development of kernicterus and neurological deficiency. In countries where there is a severe shortage of cadaveric organs, as is the case in Saudi Arabia, LRLT is the optimum treatment modality for this syndrome. 相似文献
993.
Limbal versus conjunctival autograft transplantation for advanced and recurrent pterygium 总被引:8,自引:0,他引:8
Al Fayez MF 《Ophthalmology》2002,109(9):1752-1755
PURPOSE: To compare the safety and efficacy of limbal versus conjunctival autograft transplantation for treating advanced and recurrent pterygia. DESIGN: Randomized, prospective clinical trial. PARTICIPANTS: Seventy-nine patients with advanced primary or recurrent pterygia treated by conjunctival (n = 36) or limbal-conjunctival (n = 43) autograft transplantation. INTERVENTION: Twenty four eyes with primary and 12 eyes with recurrent pterygia underwent free conjunctival autograft transplantation (group A), and 28 eyes with primary and 15 eyes with recurrent pterygia underwent limbal-conjunctival autograft transplantation (group B). MAIN OUTCOME MEASURES: Recurrence of pterygium and complications. RESULTS: With a 3-year minimum of follow-up, 2 cases of primary (8.3%) and 4 cases of recurrent (33.3%) pterygia in group A showed recurrence. No patients in group B developed recurrence. CONCLUSIONS: In this study both techniques were effective in cases of advanced primary pterygia with no statistically significant difference. Limbal transplantation appeared more effective than free conjunctival transplantation for treatment of recurrent pterygia (P < 0.05). 相似文献
994.
PURPOSE: To evaluate the efficacy of preemptive analgesia in surgical repair of retinal detachment (RD) using scleral buckle and cryopexy under general anesthesia. METHODS: Thirty patients who were scheduled for rhegmatogenous RD surgical repair using scleral buckle and cryopexy and who were American Society of Anesthesiologists physical status I, II, or III were included in this study. The patients were randomly divided into two equal groups. The surgery was done under general anesthesia in both groups, but in Group 2, sub-Tenon anesthesia was given as preemptive analgesia after induction anesthesia and before start of surgery. Both groups were statistically comparable as regards patient age and weight and duration of anesthesia and surgery. RESULTS: The incidences of intraoperative oculocardiac reflex and postoperative vomiting were significantly lower in Group 2 compared with Group 1 (P < 0.001 and 0.0113, respectively). The time of first postoperative analgesic dose was significantly shorter in Group 1 (46.67 +/- 18.84 minutes) compared with Group 2 (162.67 +/- 29.391 minutes) (P < 0.001). The total analgesic consumption per 24 hours was significantly higher in Group 1 compared with Group 2 (P < 0.001). The time of discharge from the hospital was significantly shorter in Group 2 (8.8 +/- 2.704 hours) compared with Group 1 (12.4 +/- 3.481 hours) (P = 0.0018). CONCLUSION: The use of sub-Tenon block as preemptive analgesia after induction of general anesthesia and before the start of rhegmatogenous RD surgical repair was effective in reducing postoperative pain and analgesic requirements compared with an unblocked group. The use of sub-Tenon block was also effective in reducing intraoperative incidence of oculocardiac reflex and postoperative incidence of vomiting. 相似文献
995.
Effect of squalamine on iris neovascularization in monkeys 总被引:3,自引:0,他引:3
Genaidy M Kazi AA Peyman GA Passos-Machado E Farahat HG Williams JI Holroyd KJ Blake DA 《Retina (Philadelphia, Pa.)》2002,22(6):772-778
PURPOSE: To investigate the effect of squalamine, an antiangiogenic aminosterol, in an experimental model of iris neovascularization. METHODS: Iris neovascularization was created in cynomolgus monkeys by occluding retinal veins with an argon laser and inducing persistent hypotony with a central corneal suture. Twenty-four eyes were treated in three groups. In Group 1, four eyes were injected intravitreally with 3 microg/0.1 mL squalamine and four eyes with balanced saline solution (controls) immediately after vein occlusion (day 1); injections were repeated every 3 days for 3 weeks. In Group 2, 1 mg/kg squalamine was administered with intravenous infusion in dextrose 5% in four animals; four control animals received only dextrose. Infusions began on day 1 and were repeated every 3 days for 3 weeks. In Group 3, after development of iris neovascularization on day 7, 1 mg/kg squalamine was injected systemically in four animals; four control animals received dextrose 5%. Monkeys were examined by slit-lamp biomicroscopy and underwent color photography and fluorescein angiography. RESULTS: Group 1: All eyes, treated and control, developed intense and persistent rubeosis iridis. Group 2: Two of the four treated eyes in this group developed minimal iris neovascularization; the other two had no iris neovascularization. All four control eyes developed intense, persistent iris neovascularization. Group 3: All eyes developed extensive rubeosis iridis; iris neovascularization regressed in all four treated eyes after squalamine injections. Two of four treated eyes retained minimal iris neovascularization; two showed complete regression of rubeosis iridis. Rubeosis iridis completely regressed in two of the four control eyes; the remaining two control eyes had intense, persistent iris neovascularization. CONCLUSIONS: Intravitreally injected squalamine did not affect the development of iris neovascularization; however, systemic squalamine injection inhibited the development of iris neovascularization and caused partial regression of new vessels in a primate model. 相似文献
996.
Macular serpiginous choroiditis 总被引:1,自引:0,他引:1
PURPOSE: To report a variant form of serpiginous choroiditis, that initially or predominantly involved the macular area. METHODS: Nine eyes of 6 patients with the macular form of serpiginous choroiditis were evaluated clinically and angiographically in a longitudinal fashion for a period of 12-36 months. The active stage and the recurrences were treated by oral and periocular cortico steroids; and two patients were supplemented with oral azathioprine. Most of these patients were referred to our center with varied diagnoses. RESULTS: In this group, 4 were male and 2 were female with an average age of 30.5 years. Three patients had bilateral macular lesions, two had typical serpiginous choroiditis in the fellow eye and the remaining one had unilateral macular involvement alone. The initial visual acuity was 6/60 or less in 60% eyes whereas the final visual acuity was 6/18 or better in 66% eyes. Angiographic findings were typical of serpiginous choroiditis characterised by early hypofluorescence followed by leakage and staining of the borders and the lesion itself without any evidence of choroidal ischaemia or retinal vascular abnormalities. CONCLUSION: The macular variant of serpiginous choroiditis can mimic many other macular pathologic lesions, thus posing a diagnostic dilemma. Because of its relentless destructive course, early diagnosis and prompt treatment is required to prevent sight-threatening complications. 相似文献
997.
Environmental influences on brain neurotrophins in rats 总被引:11,自引:0,他引:11
Pham TM Winblad B Granholm AC Mohammed AH 《Pharmacology, biochemistry, and behavior》2002,73(1):167-175
Environmental factors can have profound influences on the brain. Enriching environments with physical, social and sensory stimuli are now established to be beneficial to brain development and ageing. A multitude of responses from cellular and molecular mechanisms to macroscopic changes in neural morphology and neurogenesis have been considered in the context for evidences that environmental inputs can regulate brain plasticity in the rat at all stages of life. Data from our laboratory have revealed that enriched environment increased nerve growth factor (NGF) gene expression and protein levels in the hippocampus, and this may contribute to events underlying environmentally induced neural plasticity. Because neurotrophic factors are essential for neural development and survival, they are likely to be involved in the cerebral consequences modified by enriched experiences. 相似文献
998.
Effects of Sucrose and Trehalose on the Preservation of the Native Structure of Spray-Dried Lysozyme 总被引:2,自引:0,他引:2
Purpose. To investigate the effects of sucrose, trehalose, sucrose/dextran mixtures, and sucrose/trehalose mixtures on the preservation of the native structure of spray-dried lysozyme in the solid state.
Methods. The intensity of the -helical band and the melting enthalpies (Hm ) of spray-dried lysozyme in the dried form and in aqueous solution were obtained using second derivative FTIR and differential scanning calorimetry (DSC) respectively.
Results. The intensity of the -helical band and the H m of spray-dried lysozyme obtained were linearly correlated and both suggest that the stabilization of lysozyme in the dried form was excipient concentration-dependent with a close to maximum stabilization being conferred by sucrose or trehalose at a mass ratio 1–2 (sugar:enzyme). Sucrose appeared to be more effective than trehalose on a weight by weight basis whilst stabilizing effects of dextran/sucrose or trehalose/sucrose mixtures were found to be additive.
Conclusion. Dehydration during spray drying was considered the main stress to the denaturation of lysozyme. A major effect of the sugars in protecting lysozyme against dehydration was attributable to hydrogen bonding between the sugar and protein molecules, which lead to an increase in the change in the negative value of the free energy between native and denatured states. 相似文献
999.
1000.
Saleheen D Ali SA Ashfaq K Siddiqui AA Agha A Yasinzai MM 《Biological & pharmaceutical bulletin》2002,25(3):386-389
In this study the anti-proliferative effect of curcumin (curcuma longa) that is the active ingredient of ground dried rhizome has been studied against three local and three reference leishmanial strains, Leishmania major, Leishmania tropica and Leishmania infantum (Pakistani isolate). Curcumin has shown an average IC50 of 5.3 microM against promastigotes of various leishmanial strains which is much lower as compared with pentamidine that is one of the basic treatments against leishmaniasis. The main draw back attributed to these assays performed on promastigotes is the heterogeneity of results compared with those obtained with intracellular amastigotes or with in vivo effect. We also tested activity of curcumin against axenic amastigote like cells (AALC) of L. major strain (MHOM/PK/88/DESTO). Curcumin proves to be far more potent then pentamidine against AALC which further strengthens the fact about its leishmaniacidal activity. 相似文献