全文获取类型
收费全文 | 9272篇 |
免费 | 694篇 |
国内免费 | 44篇 |
专业分类
耳鼻咽喉 | 78篇 |
儿科学 | 253篇 |
妇产科学 | 56篇 |
基础医学 | 1197篇 |
口腔科学 | 186篇 |
临床医学 | 959篇 |
内科学 | 1933篇 |
皮肤病学 | 150篇 |
神经病学 | 1214篇 |
特种医学 | 689篇 |
外科学 | 1614篇 |
综合类 | 49篇 |
一般理论 | 4篇 |
预防医学 | 448篇 |
眼科学 | 159篇 |
药学 | 425篇 |
中国医学 | 6篇 |
肿瘤学 | 590篇 |
出版年
2024年 | 62篇 |
2023年 | 145篇 |
2022年 | 212篇 |
2021年 | 397篇 |
2020年 | 265篇 |
2019年 | 290篇 |
2018年 | 333篇 |
2017年 | 293篇 |
2016年 | 364篇 |
2015年 | 353篇 |
2014年 | 470篇 |
2013年 | 556篇 |
2012年 | 847篇 |
2011年 | 831篇 |
2010年 | 469篇 |
2009年 | 392篇 |
2008年 | 594篇 |
2007年 | 589篇 |
2006年 | 491篇 |
2005年 | 369篇 |
2004年 | 343篇 |
2003年 | 293篇 |
2002年 | 284篇 |
2001年 | 88篇 |
2000年 | 61篇 |
1999年 | 67篇 |
1998年 | 47篇 |
1997年 | 22篇 |
1996年 | 24篇 |
1995年 | 19篇 |
1994年 | 17篇 |
1993年 | 18篇 |
1992年 | 40篇 |
1991年 | 29篇 |
1990年 | 32篇 |
1989年 | 27篇 |
1988年 | 26篇 |
1987年 | 26篇 |
1986年 | 15篇 |
1985年 | 20篇 |
1984年 | 9篇 |
1983年 | 12篇 |
1982年 | 11篇 |
1979年 | 13篇 |
1978年 | 15篇 |
1976年 | 11篇 |
1973年 | 12篇 |
1972年 | 12篇 |
1968年 | 8篇 |
1922年 | 14篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
51.
Carolin Schmidt Ulf Liljenqvist Thomas Lerner Tobias L. Schulte Viola Bullmann 《European spine journal》2011,20(7):1118-1126
Posterior pedicle screw fixation is now the standard treatment for surgical correction of idiopathic scoliosis and has largely
replaced anterior techniques, but there have been reports describing a lordogenic effect of segmental pedicle screw instrumentation
in the thoracic spine. This clinical study compared anterior dual rod instrumentation with posterior pedicle screw fixation
for idiopathic thoracic lordoscoliosis, including 42 patients (7 male, 35 female; average age 16 years, range 12–34) who underwent
posterior pedicle screw fixation (n = 20) or anterior dual rod instrumentation (n = 22) at two centers. The average follow-up period was 33 months (24–108 months). Inclusion criteria were a diagnosis of
adolescent idiopathic scoliosis with a structural thoracic curve (Lenke 1–3) and thoracic hypokyphosis (T4–T12 < 20°). The
main thoracic curve magnitude and sagittal profile on standing radiographs were evaluated. Thoracic kyphosis was significantly
restored from preoperatively 10.2° to 23.4° postoperatively in the anterior group and from 7.6° to 12.9° in the posterior
group (P < 0.005). Kyphosis improved significantly better in the anterior group than in the posterior group (P < 0.005). The preoperative and postoperative main thoracic curve values were 63° (48–80°) and 25.2° in the anterior group
and 60.6° (50–88°) and 23.6° in the posterior group, with no significant differences between the groups. No neurological or
other severe complications were observed. Anterior dual rod instrumentation in patients with thoracic lordoscoliosis allows
significantly better restoration of thoracic kyphosis than posterior pedicle screw instrumentation. 相似文献
52.
Tobias Kleinjung Peter Eichhammer Michael Landgrebe Philipp Sand Goeran Hajak Thomas Steffens Juergen Strutz Berthold Langguth 《Otolaryngology--head and neck surgery》2008,138(4):497-501
OBJECTIVES: Low-frequency repetitive transcranial magnetic stimulation (rTMS) of the temporal cortex has been proposed as a new treatment strategy for patients with chronic tinnitus. However, functional abnormalities in tinnitus patients also involve brain structures used for attentional and emotional processing, such as the dorsolateral prefrontal cortex. Therefore, we have developed a new rTMS treatment strategy for tinnitus patients that consists of a combination of high-frequency prefrontal and low-frequency temporal rTMS. STUDY DESIGN: A total of 32 patients received either low-frequency temporal rTMS or a combination of high-frequency prefrontal and low-frequency temporal rTMS. Treatment effects were assessed with a standardized tinnitus questionnaire (TQ). RESULTS: Directly after therapy there was an improvement of the TQ-score for both groups, but no differences between groups. An evaluation after 3 months revealed a remarkable benefit from the use of combined prefrontal and temporal rTMS treatment. CONCLUSION: These results support recent data that suggest that auditory and nonauditory brain areas are involved in tinnitus pathophysiology. 相似文献
53.
Deuse T Schrepfer S Reichenspurner H Hoyt G Fischbein MP Robbins RC Pelletier MP 《Transplant immunology》2007,17(4):255-261
BACKGROUND: Different animal models have been developed to study the pathogenesis and treatment of obliterative airway disease (OAD). Here we describe the techniques of heterotopic and orthotopic tracheal transplantations in the rat, comparing the kinetics of systemic host immune response and of histopathologic OAD development. METHODS: Heterotopic and orthotopic tracheal transplantations were performed in both allogeneic (Brown Norway-to-Lewis) and syngeneic (Lewis-to-Lewis) models. Grafts were harvested after 7, 30, and 60 days post-transplant for histologic evaluation and analysis of host cellular and humoral response. RESULTS: Syngeneic tracheal grafts did not develop luminal obliteration and were morphologically indistinguishable from native tracheas. In heterotopic allografts, airway epithelium was rapidly destroyed and OAD progressed with complete luminal occlusion by 30 days. Orthotopic allografts showed enhanced early infiltration (1298+/-45 vs. 674+/-75 cells/high power field, p<0.001) with concomitant greater day 7 luminal narrowing (45+/-6% vs. 14+/-3%, p<0.001). In this model, donor-type BN epithelium (62+/-17%, 21+/-19%, and 1+/-1% on days 7, 30, and 60) was gradually replaced by recipient-type epithelial cells (2+/-4%, 70+/-22%, and 98+/-2%). OAD developed with circular orientation of cells and connective tissue fibers to 45+/-6% obliteration by day 60. Cellular host response, as determined by IFN-gamma-ELISPOT assay (548+/-132 vs. 402+/-197 spots, p=0.046) and anti-donor alloreactive IgM antibody production (2827+/-148 vs. 1565+/-393 mean channel fluorescence, p<0.001) were significantly stronger in rats bearing orthotopic vs. heterotopic allografts. CONCLUSIONS: The orthotopic tracheal transplantation model may be more representative of OAD found in human lung transplant recipients and we therefore encourage the wider use of this model. 相似文献
54.
The anesthesia care of a 14-year-old female patient with an acute exacerbation of myasthenia gravis (MG) and a full stomach who required emergency surgery for placement of a hemodialysis catheter is described. A nonventilated rapid sequence induction was successful with the use of propofol, lidocaine, remifentanil, cricoid pressure and no neuromuscular blocking agent. Although the use of combinations of i.v. anesthetic agents have been suggested for tracheal intubation without the need for neuromuscular blocking agents, none of these techniques has been advocated for rapid sequence intubation. We review existing literature on the topic of tracheal intubation using remifentanil and propofol without a neuromuscular blocking agent and on the topic of tracheal intubation of patients with MG using i.v. anesthesia and no neuromuscular blocking agents. 相似文献
55.
Per-Anton Westerberg Torbj?rn Linde Bj?rn Wikstr?m Osten Ljunggren Mats Stridsberg Tobias E Larsson 《Nephrology, dialysis, transplantation》2007,22(11):3202-3207
BACKGROUND: Fibroblast growth factor-23 (FGF23) is a circulating factor that regulates the renal reabsorption of inorganic phosphate (Pi) and is increased in chronic kidney disease (CKD). The aim of the current investigation was to study the regulation of FGF23 in CKD subjects with various degree of renal function. As such, we analysed the relationship between FGF23, Pi, calcium, parathyriod hormone (PTH), 25(OH) vitamin D3(25(OH)D3), 1,25(OH)2 vitamin D3(1,25(OH)2D3) and estimated glomerular filtration rate (eGFR). METHODS: Intact FGF23 and other biochemical variables were analysed in 72 consecutive adult out-patients with various stages of CKD (eGFR ranging from 4-96 ml/min.) Association studies were performed using linear univariate and multivariate analysis. RESULTS: FGF23 was significantly elevated at CKD stage 4 (266 +/- 315 pg/ml, P < 0.001) and 5 (702 +/- 489 pg/ml, P < 0.001) compared with CKD 1-2 (46 +/- 43 pg/ml). In CKD 4-5 an independent association between log FGF23 and Pi (P < 0.001), 25(OH)D3 (P < 0.05) as well as eGFR (P < 0.01) was observed. In contrast, in CKD 1-3 log PTH (P < 0.05) was the only independent predictor of log FGF23 in multivariate analysis. In CKD 1-5, Pi (P < 0.00001) and log PTH (P < 0.01) were explanatory variables for log FGF23 in multivariate analysis. CONCLUSIONS: We conclude that serum FGF23 increases in CKD 4-5, in parallel with the emerging hyperphosphataemia. Serum Pi is the most important predictor of FGF23 when GFR is less than 30 ml/min. In contrast, our data suggest that Pi may not be an important determinant of FGF23 in normophosphataemic CKD subjects. Finally, the association between FGF23 and PTH in CKD may suggest a co-regulation that remains to be further elucidated. 相似文献
56.
Lerner T Frobin W Bullmann V Schulte T Brinckmann P Liljenqvist U 《Journal of spinal disorders & techniques》2007,20(3):195-202
INTRODUCTION: In scoliosis patients treated with long segment spinal fusion, degenerative changes like retrolisthesis and disc space narrowing below fusion have been observed. However, there is disagreement concerning their incidence and dependency on the location of the lowest instrumented vertebra. MATERIALS AND METHODS: To evaluate temporal changes in disc height and posteroanterior displacement (indicating listhesis) below fusion, 40 patients with adolescent idiopathic scoliosis, mainly treated with Cotrel-Dubousset instrumentation, were retrospectively investigated in this longitudinal study with a follow-up of on average 9.2 years (median 9.4 y) after surgery. Disc height and displacement were measured from lateral radiographs by means of distortion-compensated roentgen analysis (DCRA). Additionally, a mathematical model was developed to determine the influence of vertebral tilt in scoliosis on disc height and displacement. RESULTS: Overall, no significant decrease in disc height was observed during follow-up. Concerning listhesis a small but significant retrolisthesis was found in segments L2/L3 and L3/L4. Compared with normative data, there was no significant listhesis for the L5/S1 segment. Nevertheless, separating the study group into subsamples of identical distal fusion level revealed a significant correlation between the amount of posteroanterior displacement at L5/S1 and the location of the lowest instrumented vertebra. With a reduction of free motion segments, listhesis increased into posterior direction. Taking the tilt correction into account led to considerably increased values of disc height whereas displacement was affected only to a minor degree. CONCLUSIONS: Long segment spinal fusion in young patients with idiopathic scoliosis did not lead to disc space narrowing during 9.2 years follow-up. However, the observed increase in retrolisthesis potentially indicates the initiation of a degenerative process. These only minimal changes might be referred to the preservation of a physiologic lumbar lordosis. Without correction for vertebral tilt disc space narrowing is overestimated. 相似文献
57.
Influence of different approaches to the cerebellopontine angle on the function of the intermediate nerve 总被引:1,自引:0,他引:1
Stripf T Braun K Gouveris H Stripf EA Mann WJ Amedee RG 《Journal of neurosurgery》2007,107(5):927-931
OBJECT: Surgery in the cerebellopontine angle (CPA) is a standard procedure at many centers. Outcome is focused mainly on preservation of hearing and facial function postoperatively. The nonmotor part of the facial nerve, the intermediate nerve, is nearly neglected nowadays. METHODS: A retrospective study was designed, including a questionnaire that was sent to 178 patients who had undergone surgery between 2000 and 2004. Data were obtained in 156 cases. The questionnaire was divided into five parts assessing the presence of increased tearing, reduced tearing, salivation disturbances, increased nasal secretions, and abnormalities in taste. Finally, a self-assessment of patient symptoms was analyzed. RESULTS: Postoperatively, 70 patients (45%) experienced crocodile tears, whereas 62 (40%) had dry eyes. Disturbances in taste were noted in six patients (4%) preoperatively and in 52 patients (33%) after surgery. Increased nasal secretion was noted in 68 patients (44%) postoperatively. An analysis of the correlation between the surgical approach used and disturbances in the intermediate nerve revealed a strong tendency to a higher rate of symptoms following the middle fossa approach (p = 0.071, chi-square test). CONCLUSIONS: Data in this study demonstrate the clinical importance of nonmotor defects associated with CPA tumor removal. More than 50% of the patients in this study reported postoperative crocodile tears, dry eyes, nasal secretions, and/or taste disturbances. These sequelae may affect both short- and long-term postoperative quality of life to the same extent as deafness or transient facial paresis. The risk of injury seems to be higher after the middle fossa approach. 相似文献
58.
Kathrin?Markert Tobias?Haltmeier Tatsiana?Khatsilouskaya Marius?J.?Keel Daniel?Candinas Beat?SchnürigerEmail author 《World journal of surgery》2018,42(12):3947-3953
Background
In patients undergoing non-operative management (NOM) of blunt splenic and/or liver injuries, no data exist on the safety of same-admission surgery in prone position for concomitant injuries.Methods
Retrospective study including adult trauma patients with blunt splenic/liver injuries and attempted NOM from 01/2009 to 06/2015 was conducted. Patient and injury characteristics as well as outcomes [failed (f)NOM, mortality] of patients with/without surgery in prone position were compared (‘prone’ vs. ‘non-prone’ group).Results
A total of 244 patients with blunt splenic/liver injury and attempted NOM were included. Forty patients (16.4%) underwent surgery in prone position on median post-injury day 2.0 [interquartile range (IQR) 3.0]. Surgery in prone position was mostly performed for associated spinal or pelvic injuries. The ISS was significantly higher, and the proportion of patients with high-grade injuries (OIS?≥?3) was significantly less frequent in the ‘prone? group (30.0?±?14.5 vs. 23.9?±?13.2, p?=?0.009 and 27.5 vs. 53.9%, p?=?0.002). In-hospital mortality as well as NOM failure rates were not significantly different between the ‘prone’ and ‘non-prone? group (2.5 vs. 2.9%, p?=?1.000; 0.0 vs. 4.4%, p?=?0.362). Eleven patients with high-grade injuries were operated in prone position at median day 3 (IQR 3.0). None of these patients failed NOM. However, one patient with a grade IV splenic injury required immediate splenectomy after being operated in right-sided position on the day of admission.Conclusion
In this single-center analysis, surgery in prone position was performed in a substantial number of patients with splenic/liver injuries without increasing the fNOM rate. However, caution should be used in patients with grade IV/V splenic injuries.59.
Thomas Alserius Russell E. Anderson Niklas Hammar Tobias Nordqvist 《Scandinavian cardiovascular journal : SCJ》2013,47(6):392-398
Objective. To evaluate if glycosylated haemoglobin 1 (HbA1c) was associated with increased risk of infection and mortality after coronary artery bypass grafting (CABG). Design. Prospective observational study. Preoperative HbA1c concentrations were correlated to outcome in patients followed for an average of 3.5 years after CABG. Results. HbA1c was ≥6% in 68% of 161 patients with diabetes mellitus (DM) and in 3% of 444 patients without DM. Superficial sternal wound infection was observed in 13.9% if HbA1c ≥6% versus in 5.5% if <6% (p=0.007). Mediastinitis occurred in 4.9% if HbA1c≥6% and in 2.1% if HbA1c<6% (p=0.20) (Hazard ratio (HR) 1.9, 95% CI 0.6-5.9). Follow-up mortality was 18.9% in patients with HbA1c≥6% compared to 4.1% if HbA1c<6% (p<0.001) with HR 5.4, (95% CI 3.0-10.0) after multivariable adjustment. The risk of death was similar regardless of DM diagnosis. Conclusions. HbA1c ≥6% was associated with an increased risk of postoperative superficial sternal wound infections and a trend for higher mediastinitis rate and significantly higher mortality three years after CABG. 相似文献
60.
Cantz T Sharma AD Jochheim-Richter A Arseniev L Klein C Manns MP Ott M 《Cell transplantation》2004,13(6):659-666
We have investigated the contribution of intrasplenic bone marrow transplants or in vivo mobilized hematopoietic stem cells to the formation of hepatocytes in normal and injured liver. Direct intrasplenic injections of bone marrow mononuclear cells (5 x 10(5) cells), Scal+/lin- hematopoietic stem cells (5 x 10(3)) cells, and highly purified "side population" hematopoietic stem cells (5 x 10(3)) derived from enhanced green fluorescent protein (EGFP)-transgenic mice [C57Bl/6-TgN(ActbEGFP)1Osb] were performed in normal C57Bl/6 mice (n = 6) and in C57Bl/6 mice following two thirds hepatectomy (n = 8). To test the effect of mobilized stem cells on transdifferentiation, C57Bl/6 mice (n = 12) were lethally irradiated and reconstituted with EGFP-positive bone marrow mononuclear cells in a second series of experiments. Eight to 12 weeks after bone marrow transplantation a subset of mice (n = 3 in each group) received either rhG-CSF for hematopoietic stem cell mobilization, rhG-CSF combined with an intraperitoneal application of carbon tetrachloride (CCl4) as hepatocyte regeneration stimulus, or CCl4 alone. All mice were completely perfused with PBS to remove circulating nonorgan cells for analyses 4 weeks later. Liver as well as heart, intestine, spleen, and kidney tissue was analyzed for the presence of EGFP-transgenic cells. In 100 sections (2.3 x 10(7) cells) of any recipient mouse no EGFP-positive hepatocytes were detected either by analysis of native EGFP fluorescence or by immunofluorescence analysis with anti-EGFP and antidipeptidyl peptidase (DPP) IV antibodies. EGFP-transgenic cells resembling heart, kidney, or intestinal cells could also not be proven. The results demonstrate that there is little or no contribution of bone marrow-derived cells to the regeneration of normal and injured liver in the animal models used. Thus, potential therapeutic prospects of hematopoietic stem cell therapy for liver disease have to be critically reassessed. 相似文献