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81.
Long-term bone marrow cultures (LTBMC) from patients with multiple myeloma (MM) and normal donors were analyzed for immunophenotype and cytokine production. Both LTBMC adherent cells from myeloma and normal donor origin expressed CD10, CD13, the adhesion molecules CD44, CD54, vascular cell adhesion molecule 1, very late antigen 2 (VLA-2), and VLA- 5, and were positive for extracellular matrix components fibronectin, laminin, and collagen types 3 and 4. LTBMC from myeloma patients and normal donors spontaneously secreted interleukin-6 (IL-6). However, levels of IL-6 correlated with the stage of disease; highest levels of IL-6 were found in LTBMC from patients with active myeloma. To identify the origin of IL-6 production, LTBMC from MM patients and normal donors were cocultured with BM-derived myeloma cells and cells from myeloma cell lines. IL-6 was induced by plasma cell lines that adhered to LTBMC such as ARH-77 and RPMI-8226, but not by nonadhering cell lines U266 and FRAVEL. Myeloma cells strongly stimulated IL-6 secretion in cocultures with LTBMC adherent cells from normal donors and myeloma patients. When direct cellular contact between LTBMC and plasma cells was prevented by tissue-culture inserts, no IL-6 production was induced. This implies that intimate cell-cell contact is a prerequisite for IL-6 induction. Binding of purified myeloma cells to LTBMC adherent cells was partly inhibited by monoclonal antibodies against adhesion molecules VLA-4, CD44, and lymphocyte function-associated antigen 1 (LFA-1) present on the plasma cell. Antibodies against VLA-4, CD29, and LFA-1 also inhibited the induced IL-6 secretion in plasma cell-LTBMC cocultures. In situ hybridization studies performed before and after coculture with plasma cells indicated that LTBMC adherent cells produce the IL-6. These results suggest that the high levels of IL-6 found in LTBMC of MM patients with active disease are a reflection of their previous contact with tumor cells in vivo. These results provide a new perspective on tumor growth in MM and emphasize the importance of plasma cell-LTBMC interaction in the pathophysiology of MM.  相似文献   
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Evaluation of structural bone grafts risk of failure requires noninvasive quantitative predictors of functional strength. We hypothesized that a quantitative graft‐to‐host union biometric would correlate significantly with biomechanical properties as a surrogate for the risk of fracture. To test this, we developed a novel algorithm to compute the union between host callus and graft, which was termed the union ratio. We compared the union ratio of live autografts to devitalized allografts implanted into the mid‐diaphysis of mouse femurs for 6 and 9 wk. Surprisingly, the autograft union ratio decreased from 0.228 ± 0.029 at 6 wk to 0.15 ± 0.011 at 9 wk (p < 0.05) and did not correlate with the torsional properties of the autografts. The allograft union ratio was 0.105 ± 0.023 at 6 wk but increased to 0.224 ± 0.029 at 9 wk (p < 0.05). As a single variable, the union ratio correlated significantly with ultimate torque (R2 = 0.58) and torsional rigidity (R2 = 0.51) of the allografts. Multivariable regression analyses of allografts that included the union ratio, the graft bone volume, the maximum and minimum polar moment of inertia, and their first‐order interaction terms with the union ratio as independent variables resulted in significant correlations with the ultimate torque and torsional rigidity (adjusted R2 = 0.80 and 0.89, respectively). These results suggest that, unlike live autografts, the union between the devitalized allograft and host contributes significantly to the strength of grafted bone. The union ratio has important clinical implications as a novel biometric for noninvasive assessment of functional strength and failure risk.  相似文献   
84.
Accurate pregnancy dating is vital to obstetric management. However, first trimester fetal charts commonly used in Australia rely on data reported more than three decades ago. This study reports first trimester dating and growth charts for crown‐rump length between 5 and 14 weeks of gestation and biparietal diameter between 9 and 14 weeks of gestation on an Australia population using modern real‐time ultrasound equipment. All consenting eligible women attending a large Sydney clinic for first trimester ultrasound between March 2005 and December 2006 were recruited. Measurements were carried out to Australasian Society for Ultrasound in Medicine standard protocols. Statistical analyses were undertaken using polynomial regression models and thorough diagnostic checks made. Overall 396 eligible women consented to the study, with 268 between 9 and 14 weeks of gestation. The average participant age was 34 years (range 22–45 years), 371 and all yielded valid biometry measurements. Equations, means and 90% reference intervals for crown‐rump length measurements and biparietal diameter measurements were derived using polynomial regression models. Thorough residual and diagnostic checks were made. Once validated by others, we believe they will warrant consideration for use by Australasian Society for Ultrasound in Medicine.  相似文献   
85.
A cross sectional study assessed the bone mineral density (BMD) of 20 young adult patients who received a renal transplantation in childhood. The BMD of the lumbar spine, mainly trabecular bone, and of the total body, mainly cortical bone, were measured and expressed as an SD score. Fourteen patients (70%) had a BMD SD score of the lumbar spine below -1, of whom six patients were below -2. Fifteen patients (75%) had a BMD SD score of the total body below -1, of whom seven patients were below -2, Both trabecular and cortical bone appeared to be involved in the osteopenic process. The cumulative dose of prednisone was inversely correlated to both lumbar spine and total body BMD SD score. In a multiple regression analysis the cumulative dose of prednisone appeared to be the only factor with a significant effect on BMD SD score. Most young adult patients who had received a renal transplantation in childhood had moderate to severe osteopenia. Corticosteroid treatment played a major part in the development of osteopenia in these patients.  相似文献   
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87.
Synthesis and antimicrobial activities of N-substituted imides   总被引:1,自引:0,他引:1  
In the field of our research programs concerning novel antimicrobial agents, a series of N-substituted imides was synthesized. These compounds were obtained by cyclization of amido-acids in acetic anhydride/sodium acetate or hexamethyldisilazane/zinc bromide for the hydroxy-aromatic derivatives. The hydroxy-alkyl maleimides were directly prepared by condensation of the corresponding amino-alcohol with maleic anhydride in boiling toluene. Most of N-substituted maleimides showed an interesting antimicrobial activity towards bacteria from the ATCC collection (Staphylococcus aureus ATCC 25923, Enterococcus faecalis ATCC 29212, Escherichia coli ATCC 25922 and Pseudomonas aeruginosa ATCC 27853) but the MIC values for P. aeruginosa were always high (128 microg/ml). The imides with alkyl substituents showed higher activities than aromatic analogues with MIC values in the range of 8-32 microg/ml. Comparatively, succinimides were practically inactive.  相似文献   
88.
PURPOSE: Intravesical morphine was recently recommended to reduce postoperative pain after reimplantation surgery for vesicoureteral reflux in children. The efficacy of such treatment, so far solely evaluated by open study, needed to be confirmed. MATERIALS AND METHODS: After parental informed consent was obtained, 80 children requiring Cohen cross-trigonal reimplantation were considered for inclusion in a double-blind study. On the day of surgery patients were randomly assigned to receive either 0.04 mg./kg. morphine per hour or placebo (normal saline) at a constant intravesical infusion rate of 0.08 ml./kg. per hour. Postoperative pain was assessed every 3 hours using a pain score adapted to patient age. If the score was above a predefined limit, patients received intravenous acetaminophen and nalbuphine alternately every 3 hours. Bladder infusion was discontinued after 48 hours. RESULTS: Mean and maximum pain scores as well as the number of scores above the limit were not statistically different when comparing the morphine and placebo groups. There was no difference in the number of doses of analgesics administered. Urine output, voiding frequency and the number of painful voiding episodes were not significantly different between the 2 groups. Plasma morphine concentrations were 3.0 +/- 2.7 and 1.9 +/- 1.9 ng./ml. at 24 and 48 hours in the morphine group and undetectable in the placebo group. CONCLUSIONS: Intravesical administration of morphine is not effective for relieving postoperative pain during the first 48 hours after intravesical ureteral reimplantation. This study emphasizes the importance of controlled studies in evaluating the effectiveness of a new drug or procedure before recommending its use for all patients.  相似文献   
89.
We have demonstrated previously the ability of apoptotic cells to prime a functional immune response using an i.p. vaccination protocol with apoptotic cells and interleukin 2, before injecting a lethal dose of tumor cells into syngeneic rats. This protocol resulted in a survival rate of 33%. To elucidate the nature and the activity of the phagocytes involved in the clearance of apoptotic cells in vivo, we modulated the peritoneal cavity environment by administrating either thioglycollate or silica i.p. before injecting the apoptotic cells. Our results showed that thioglycollate abrogated vaccination efficiency, because none of the rats survived under these conditions. In fact, thioglycollate treatment induced a massive recruitment and activation of inflammatory macrophages that efficiently engulfed apoptotic cells, bypassing induction of specific immune responses. In contrast, silica treatment enhanced the vaccination efficiency of apoptotic cells plus interleukin 2 up to 66%. We distinguished a population of dendrite-like cells among the cells derived from the silica-treated peritoneal cavity both by their phenotype (MHC II(+)/CD80(+)/CD86(+)) and by their ability to induce the proliferation of allogeneic T cells in a mixed leukocyte reaction. Our results demonstrate the different roles of macrophages and dendritic-like cells in the physiological clearance of dead tumor cells and their implication in the design of immunomodulating vaccines.  相似文献   
90.
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