全文获取类型
收费全文 | 4057篇 |
免费 | 234篇 |
国内免费 | 23篇 |
专业分类
耳鼻咽喉 | 40篇 |
儿科学 | 113篇 |
妇产科学 | 78篇 |
基础医学 | 473篇 |
口腔科学 | 153篇 |
临床医学 | 280篇 |
内科学 | 849篇 |
皮肤病学 | 58篇 |
神经病学 | 188篇 |
特种医学 | 159篇 |
外科学 | 677篇 |
综合类 | 151篇 |
一般理论 | 4篇 |
预防医学 | 239篇 |
眼科学 | 84篇 |
药学 | 445篇 |
中国医学 | 39篇 |
肿瘤学 | 284篇 |
出版年
2023年 | 30篇 |
2022年 | 77篇 |
2021年 | 187篇 |
2020年 | 77篇 |
2019年 | 128篇 |
2018年 | 147篇 |
2017年 | 107篇 |
2016年 | 97篇 |
2015年 | 116篇 |
2014年 | 173篇 |
2013年 | 234篇 |
2012年 | 323篇 |
2011年 | 316篇 |
2010年 | 191篇 |
2009年 | 158篇 |
2008年 | 213篇 |
2007年 | 209篇 |
2006年 | 204篇 |
2005年 | 180篇 |
2004年 | 169篇 |
2003年 | 136篇 |
2002年 | 132篇 |
2001年 | 65篇 |
2000年 | 67篇 |
1999年 | 43篇 |
1998年 | 17篇 |
1997年 | 15篇 |
1996年 | 21篇 |
1995年 | 13篇 |
1994年 | 10篇 |
1993年 | 14篇 |
1992年 | 34篇 |
1991年 | 22篇 |
1990年 | 29篇 |
1989年 | 36篇 |
1988年 | 19篇 |
1987年 | 27篇 |
1986年 | 29篇 |
1985年 | 21篇 |
1984年 | 30篇 |
1983年 | 25篇 |
1982年 | 20篇 |
1981年 | 15篇 |
1979年 | 19篇 |
1978年 | 26篇 |
1977年 | 13篇 |
1974年 | 7篇 |
1973年 | 9篇 |
1972年 | 12篇 |
1970年 | 10篇 |
排序方式: 共有4314条查询结果,搜索用时 15 毫秒
1.
Nirmanmoh Bhatia Buddhadeb Dawn Tariq S. Siddiqui Marcus F. Stoddard 《Texas Heart Institute journal / from the Texas Heart Institute of St. Luke's Episcopal Hospital, Texas Children's Hospital》2015,42(1):16-24
Determining aortic stenosis (AS) severity is clinically important. Calculating aortic valve (AV) area by means of the continuity equation assumes a circular left ventricular outflow tract (LVOT). The full impact of this assumption in calculating AV area is unknown. Predictors of noncircular LVOT shape in patients with AS are undefined.In 109 adult patients with AS who underwent multiplanar transesophageal echocardiography, we calculated AV area by means of the standard continuity method and by a modified method involving planimetric LVOT area.We found 54 circular, 37 horizontal-oval, 8 vertical-oval, and 10 irregular LVOTs. Area derived by direct planimetry correlated better with the modified than the standard continuity method (r=0.89 vs r=0.85; both P=0.0001). Valve areas of patients with mild, moderate, or severe AS by planimetry were more often mischaracterized with use of the standard than modified method (29 vs 18; P <0.0001). Horizontal-oval AV area derived by planimetry (1.28 ± 0.55 cm2) was underestimated by the standard method (1.05 ± 0.47 cm2; P=0.001), but not by the modified method. Congenital AV morphology and low cardiac index were the only multivariate predictors of horizontal-oval shape. Low cardiac index was the only predictor of noncircular shape.More than half our patients with AS had noncircular LVOTs. Using the modified method reduces mischaracterizations of AS severity. Congenital AV morphology and low cardiac index predict horizontal-oval or noncircular shape. These data suggest the value of direct LVOT measurement to calculate AS severity in patients who have congenital AV or a low cardiac index. 相似文献
2.
Robert N. Page Lee Dittrich Roy King Fouad Boulos David L. Page 《Journal of cutaneous pathology》2009,36(11):1206-1209
Originally described by Rosen in 1983, syringomatous nipple adenoma (SAN) is a tumor of disputed histogenesis, which can be problematic both diagnostically and therapeutically. 1 It is a benign primary tumor of breast epithelium with histology similar to that of the syringoma. In the current case, we describe a 40-year-old female with this lesion occurring within a supernumerary breast. This case represents, to our knowledge, the first such reported case, and represents a significant finding as its presence could lend some confusion as to whether or not this represents a benign primary process of breast or a potentially infiltrative tumor of the skin. 相似文献
3.
Transabdominal sacrocolpopexy has been shown, in multiple long-term studies of its success and durability, to be the definitive
treatment option for post-hysterectomy vaginal vault prolapse. It is, however, associated with greater morbidity than vaginal
repair. We describe a minimally invasive technique for vaginal vault prolapse repair and present our experience with a minimum
of one-year follow-up. The surgical technique involves five laparoscopic ports—three for the da Vinci robot and two for the
assistant. After appropriate dissection a polypropylene mesh is attached to the sacral promontory and to the vaginal apex
by use of Gore-Tex sutures. The mesh material is then covered by the peritoneum. Patient analysis focused on complications,
urinary continence, patient satisfaction, and morbidity, with a minimum of 12 months follow-up. Forty-two patients with post-hysterectomy
vaginal vault prolapse underwent robot-assisted laparoscopic sacrocolpopexy at our institute and 35 have a minimum of 12 months
follow-up, with a mean follow-up of 36 months (range 12–48) in the group. Mean age was 67 (47–83) years and mean operating
time was 3.1 (2.15–4.75) h for the entire cohort. All but one patient were discharged home on postoperative day one; one patient
left on postoperative day two. One developed recurrent grade three rectocele, one had recurrent vault prolapse, and two suffered
from vaginal extrusion of mesh. All patients were satisfied with their outcome. The robot-assisted laparoscopic sacrocolpopexy
is a minimally invasive technique for vaginal vault prolapse repair, combining the advantages of open sacrocolpopexy with
the reduced morbidity of laparoscopy. We observed reduced hospital stay, low occurrence of complications, and high patient
satisfaction, with a minimum of 1-year follow-up. Most importantly, the long-term results of the robotic repair are similar
to those of open repair, but with significantly less morbidity. 相似文献
4.
R. Lazzara A. A. Siddiqui P. Binon S. A. Feldman R. Weiner R. Phillips A. Gonshor 《Clinical oral implants research》1996,7(1):73-83
Osseointegrated dental implants have now become an accepted form of treatment for patients with a fully or partially missing dentition. The purpose of this study was to evaluate the performance of 3i threaded and cylindrical implants. During a 5-year period, a total of 1969 3i endosseous implants were placed at 6 centers in the United States and 2 elsewhere in the edentulous and partially edentulous jaws of 653 consecutive patients ranging in age from 18 to 82 years. Of the total number of implants placed, 1341 were commercially pure titanium threaded implants and 628 were titanium plasma-sprayed implants with a cylindrical configuration. A total of 28 patients with 110 implants were lost to follow-up. Implants in these patients were considered neither a success nor a failure. Success was predicated on the osseointegration of each and every implant followed in this analysis rather than the persistence of prosthetic function. Confirmed bone anchorage was considered essential for success. A total of 625 patients with 1871 implants remain in the study with a follow-up period ranging from 6 to 60 months. A total of 93 implants (5.0% of the total implants followed) were considered as failures. A mean implant survival rate was 95.0% for both the threaded and the cylindrical implant was calculated. The success rate of threaded implants was 97.0% in the mandible and 93.8% in the maxilla. The success rate for the 3.3mm cylindrical implants was 96.0% in the mandible and 95.5% in the maxilla, and the success rate of 4.0mm diameter cylindrical implants was 95% in the mandible and 92.0% in the maxilla. Causes of failure consisted of loss of osseointegration 2.3%crestal bone loss requiring periodontal therapy after the first year of function 1.7% and mechanical problems associated with the prosthesis 0.9%. This retrospective analysis of the 3i endosseous implant system is comparable to previous reports on other implant systems in terms of implant survival and prosthesis stability. It is demonstrated that 3i implants are predictable and can provide lasting osseointegration leading to improvement of oral function if the recommended surgical and restorative protocol is followed. 相似文献
5.
F. Fouad K. Johny. S. Kaaba T. O. Alkarmi P. SHARMA S. Al-Harbi 《International journal of immunogenetics》1994,21(1):11-14
HLA alleles were studied in Kuwaiti patients with Systemic lupus erythematosus (SLE). Although significant association of B5, B8, and DR3 has been reported in the literature, the most common phenotype for our patients is A3, DR2 as susceptible alleles and DQ1 as a protective gene. 相似文献
6.
F M Fouad P G Farrell W D Marshall R Scherer G Ruhenstroth-Bauer 《Journal of toxicology and environmental health》1992,36(1):43-57
A useful framework is proposed for unifying the synthesis of plasma proteins and their degradation by, or release from, liver cells of intact and partially hepatectomized rats, in which synthesis and release of acute-phase plasma proteins occur in synchrony with the internalization and catabolism of plasma and extracellular proteins. The catabolism of proteins and other hepato-intracellular glycoproteins during sepsis or trauma is essential to provide constituent amino acids and carbohydrates for the synthesis of acute-phase plasma proteins. Increases in the plasma levels of acute-phase response proteins in sham-operated rats reached a maximum between 1 and 2 d after mock surgery, and had returned virtually to control levels within 6 d. By contrast, acute-phase proteins in the plasma of partially hepatectomized rats were decreased by 10-20% of their initial values after 24 h. A maximum acute-phase response on d 7 after the operation was characterized by an increase of 181, 445, and 19% for alpha-1-acid glycoprotein, hepatoglobin, and hemopexin, whereas other acute-phase proteins remained below control levels, for example, by 11, 25, and 38% for albumin, transferrin, and prealbumin, respectively. This delayed response suggests that the nascent liver cells had inherited the capacity of the parent cells to respond to inflammatory signal and had synthesized acute-phase plasma proteins. Accordingly, a time frame for the application of toxin to nascent hepatocytes is suggested. An increased activity (300 +/- 50%) for both bound and free neuraminidase in remnant liver tissue 19 h post partial hepatectomy suggested that hepatic regenerating factor(s) were produced in liver tissue via the hepatic bound and/or free neuraminidase-mediated desialylation of humoral substrates. By contrast, circulating levels of lysosomal enzymes alpha-fucosidase and beta-N-acetyl-D-glucosaminidase were increased marginally after 24 h but had returned nearly to control levels after 7 d, suggesting that lysosomal acid hydrolases do not play a major role in regenerative DNA synthesis, mitosis, or in the synthesis of acute-phase plasma proteins. 相似文献
7.
8.
A short period of maxillomandibular fixation for treatment of fractures of the mandibular tooth-bearing area. 总被引:1,自引:0,他引:1
Fouad A Al-Belasy 《Journal of oral and maxillofacial surgery》2005,63(7):953-956
PURPOSE: This study was aimed to determine whether a short period of maxillomandibular fixation (MMF) followed by an arch bar splint wired to the lower jaw is a suitable alternative to conventional MMF for treatment of fractures of the mandibular tooth-bearing area. PATIENTS AND METHODS: Thirty patients with mandibular fractures associated with no other facial fractures were selected. They were randomly assigned into 2 groups for treatment with conventional MMF (group A) and MMF for a short period of 2 weeks followed by an arch bar splint wired to the lower jaw (group B). Complications were recorded and post-treatment maximum interincisal mouth opening was measured at 1 week and 3 and 6 months. Age and gender-matched control groups were randomly selected. Groups were then compared for significant differences. A value of P < .05 was considered significant. RESULTS: The 2 patient groups were not significantly different in relation to site and cause of fracture (P =.995 and P = .682, respectively), the mean time from injury to MMF (P = .234), and the mean time required for fracture healing (P = .315). Delayed union and nonunion were not encountered, and there were no significant differences in relation to postoperative infection ( P = 1) and malocclusion (P = .598). When compared with group A patients, group B patients had an early significantly greater degree in mouth opening (P = .001); at no time was there a significant difference in the degree of mouth opening between group B patients and the control group (1 week, P = .079; 3 months, P = .166; 6 months, P = .378). CONCLUSION: In selected cases, a short period of MMF followed by an arch bar splint wired to the lower jaw is a suitable alternative to conventional MMF for treatment of fractures of the mandibular tooth-bearing area. The method is effective and significantly reduces the potential adverse effects of long-term MMF. 相似文献
9.
We have previously reported the purification of a 37 kDa platelet agglutinating protein (PAP p37) from the plasma of a patient with thrombotic thrombocytopenic purpura (TTP) that was shown to be present in a subset of TTP patients. To gain further insight into the interaction between PAP p37 and platelets, we have studied the properties of PAP p37 binding to platelets. Washed human platelets from two normal donors and two TTP patients after recovery were used for the experiments. The PAP p37 binding to platelets was specific, concentration dependent and saturable. Scatchard analysis demonstrated about 20,564-27,090 PAP p37 binding sites per platelet. Stimulation of platelets with thrombin or ADP did not have any significant effect on its binding. Thiol- and serine-specific protease inhibitors did not inhibit PAP p37 binding to the platelets. Sugars such as glucose, fructose, mannose, and sialic acid, at 40 mM, inhibited its binding to platelets by 44%, 73%, 79%, and 91% respectively, but galactose and amino sugars did not have any significant effect. At 250 micrograms/ml, Concanavalin-A inhibited 42% of binding, but other lectins, such as phytohemagglutinin-P, potato lectin and helix pomatia lectin (snail), did not. Pre-incubation of 125I-PAP p37 with the adult human IgG, decreased its binding to the platelets. The monoclonal antibodies to GP Ib (6D1) and GP IIb-IIIa complex (10E5) did not inhibit the binding of 125I-PAP p37 to platelets. Fibrinogen and von Willebrand factor did not affect the binding either. These results suggest that PAP p37 binds to platelets on the sites other than GP Ib or GP IIb-IIIa complex. 相似文献
10.
Wang S Saboorian MH Frenkel EP Haley BB Siddiqui MT Gokaslan S Wians FH Hynan L Ashfaq R 《American journal of clinical pathology》2001,116(4):495-503
This retrospective study of formalin-fixed infiltrating breast cancer specimens compared manual immunohistochemical assay with a new image analyzer-assisted immunohistochemical quantitation method, using fluorescence in situ hybridization assay (FISH) as the standard. Following the manual immunohistochemical assay, 189 cases, including most manual immunohistochemically positive and some random negative cases, were analyzed by FISH assay for Her-2/neu gene amplification and by the Automated Cellular Imaging System (ACIS) for immunohistochemical staining. Using the FISH standard, the ACIS immunohistochemical assay attained a higher concordance rate and sensitivity than the manual immunohistochemical assay (91.0% and 88% vs 85.7% and 71%, respectively), with only a slight decrease in specificity (93% vs 96%, respectively). In particular, the ACIS immunohistochemical assay resulted in a higher correlation with the FISH assay in the manual immunohistochemical assay 2+ cases. The ACIS immunohistochemical assay achieved higher accuracy than the manual method according to receiver operating characteristic curve analysis. The ACIS method represents a substantial improvement over the manual method for objective evaluation of the HER-2/neu status. 相似文献