全文获取类型
收费全文 | 441篇 |
免费 | 28篇 |
国内免费 | 9篇 |
专业分类
儿科学 | 20篇 |
妇产科学 | 5篇 |
基础医学 | 43篇 |
口腔科学 | 14篇 |
临床医学 | 50篇 |
内科学 | 121篇 |
皮肤病学 | 9篇 |
神经病学 | 8篇 |
特种医学 | 101篇 |
外科学 | 27篇 |
综合类 | 30篇 |
预防医学 | 11篇 |
眼科学 | 4篇 |
药学 | 3篇 |
肿瘤学 | 32篇 |
出版年
2023年 | 1篇 |
2021年 | 1篇 |
2020年 | 1篇 |
2019年 | 2篇 |
2018年 | 3篇 |
2017年 | 5篇 |
2016年 | 1篇 |
2015年 | 9篇 |
2014年 | 5篇 |
2013年 | 8篇 |
2012年 | 1篇 |
2011年 | 8篇 |
2010年 | 20篇 |
2009年 | 18篇 |
2008年 | 5篇 |
2007年 | 14篇 |
2006年 | 16篇 |
2005年 | 5篇 |
2004年 | 13篇 |
2003年 | 3篇 |
2002年 | 4篇 |
2001年 | 9篇 |
2000年 | 4篇 |
1999年 | 6篇 |
1998年 | 26篇 |
1997年 | 25篇 |
1996年 | 37篇 |
1995年 | 20篇 |
1994年 | 14篇 |
1993年 | 19篇 |
1992年 | 5篇 |
1991年 | 8篇 |
1990年 | 11篇 |
1989年 | 16篇 |
1988年 | 19篇 |
1987年 | 16篇 |
1986年 | 14篇 |
1985年 | 10篇 |
1984年 | 9篇 |
1983年 | 12篇 |
1982年 | 8篇 |
1981年 | 13篇 |
1980年 | 7篇 |
1979年 | 1篇 |
1978年 | 5篇 |
1977年 | 7篇 |
1976年 | 7篇 |
1975年 | 4篇 |
1973年 | 2篇 |
1972年 | 1篇 |
排序方式: 共有478条查询结果,搜索用时 31 毫秒
1.
2.
B Czerniak Z Darzynkiewicz F Herz R P Wersto L G Koss 《Materia medica Polona. Polish journal of medicine and pharmacy》1989,21(1):3-9
The basic principles of flow cytometry with special emphasis to cell cycle analysis and DNA ploidy measurements are described. The concept of separation of various subcompartments of cell cycle, distinguished by simultaneous determinations of DNA versus RNA and DNA versus protein contents is presented. Based on DNA ploidy patterns, human tumors were divided into two groups designated as diploid range and non-diploid (aneuploid). Since it has been proposed that diploid range tumors have generally better prognoses than non-diploid tumors, the value of DNA ploidy patterns as a prognostic factor is discussed in major groups of human cancers. 相似文献
3.
Repair of large midline incisional hernias with polypropylene mesh: Comparison of three operative techniques 总被引:9,自引:0,他引:9
de Vries Reilingh TS van Geldere D Langenhorst BLAM de Jong D van der Wilt GJ van Goor H Bleichrodt RP 《Hernia》2004,8(1):56-59
Polypropylene mesh is widely used for the reconstruction of incisional hernias that cannot be closed primarily. Several techniques have been advocated to implant the mesh. The objective of this study was to evaluate, retrospectively, early and late results of three different techniques, onlay, inlay, and underlay. The records of 53 consecutive patients with a large midline incisional hernia — 25 women and 28 men, mean age 60.4 (range 28–94) — were reviewed. Polypropylene mesh was implanted using the onlay technique in 13 patients, inlay in 23 patients, and underlay in 17 patients. Either the greater omentum or a polyglactin mesh was interponated between the mesh and the viscera. The records of these 53 patients were reviewed with respect to: size and cause of the hernia, pre- and postoperative mortality and morbidity, with special attention to wound complications. Patients were invited to attend the outpatient clinic at least 12 months after implantation of the mesh for physical examination of the abdominal wall. Postoperative complications occurred in 14 (26.4%) patients. The onlay technique had significantly more complications, as compared to both other techniques. Reherniation occurred in 15 (28.3%) patients. The reherniation rate of the inlay technique was significantly higher than after the underlay technique (44% vs 12%, P=0.03) and tended to be higher than the onlay technique (44% vs 23%, P=0.22). Repair of large midline incisional hernias with the use of a polypropylene mesh carries a high risk of complications and has a high reherniation rate. The underlay technique seems to be the better technique. 相似文献
4.
Nonheme iron in sickle erythrocyte membranes: association with phospholipids and potential role in lipid peroxidation 总被引:5,自引:0,他引:5
Previous studies documented the abnormal association of heme and heme proteins with the sickle RBC membrane. We have now examined RBC ghosts and inside-out membranes (IOM) for the presence of nonheme iron as detected by its formation of a colored complex with ferrozine. Sickle ghosts have 33.8 +/- 18.2 nmol nonheme iron/mg membrane protein, and sickle IOM have 4.3 +/- 3.0 nmol/mg. In contrast, normal RBC ghosts and IOM have no detectable nonheme iron. The combination of heme and nonheme iron in sickle IOM averages nine times the amount of membrane- associated iron in normal IOM. Kinetics of the ferrozine reaction show that some of this nonheme iron on IOM reacts slowly and is probably in the form of ferritin, but most (72% +/- 18%) reacts rapidly and is in the form of some other biologic chelate. The latter iron compartment is removed by deferoxamine and by treatment of IOM with phospholipase D, which suggests that it represents an abnormal association of iron with polar head groups of aminophospholipids. The biologic feasibility of such a chelate was demonstrated by using an admixture of iron with model liposomes. Even in the presence of tenfold excess adenosine diphosphate, iron partitions readily into phosphatidylserine liposomes; there is no detectable association with phosphatidylcholine liposomes. To examine the bioavailability of membrane iron, we admixed membranes and t-butylhydroperoxide and found that sickle membranes show a tenfold greater peroxidation response than do normal membranes. This is not due simply to a deficiency of vitamin E, and this is profoundly inhibited by deferoxamine. Thus, while thiol oxidation in sickle membranes previously was shown to correlate with heme iron, the present data suggest that lipid peroxidation is related to nonheme iron. In control studies, we did not find this pathologic association of nonferritin, nonheme iron with IOM prepared from sickle trait, high-reticulocyte, postsplenectomy, or iron-overloaded individuals. These data provide additional support for the concept that iron decompartmentalization is a characteristic of sickle RBCs. 相似文献
5.
6.
7.
Multiparameter flow cytometric measurements of the Ha-ras oncogene product, Ha-p21, versus DNA content were used to study the effect of prednisolone, sodium butyrate, and hyperosmolality on the expression of this gene during the cell cycle of HT-29, a human colonic carcinoma cell line. In control cells the expression of Ha-p21 was cell cycle dependent; it increased during G1 and remained approximately constant as cells traversed the S- and G2 + M phases. Two compartments of G1 cells, one expressing low (G1A) and the other (G1B) high levels of Ha-p21 could be identified. Cells grown with prednisolone (1.4-2.1 microM) expressed higher Ha-p21 levels than controls. Cell cycle analysis revealed that this effect was accompanied by a change in the distribution of cells in G1 phase: whereas the proportion of cells in G1A was reduced, that of cells in G1B was increased. The steroid had no detectable effect on cells in S and G2 + M. By contrast, sodium butyrate and hyperosmolality caused a marked decrease in Ha-p21 content. This reduction was not accompanied by any modification of the proportion of cells in the cell cycle compartments. These results would suggest that Ha-p21 is not likely to be a primary regulator of cell cycle progression in HT-29 cells. 相似文献
8.
9.
J S Coon A D Deitch R W de Vere White L G Koss M R Melamed J E Reeder R S Weinstein R P Wersto L L Wheeless 《Cancer》1989,63(8):1592-1599
The National Cancer Institute's Flow Cytometry Network (NCI-FCN) is attempting to facilitate the transfer of flow cytometry (FCM) of exfoliated bladder cells from the research laboratory to the clinical laboratory. Demonstrating interinstitutional consistency in FCM analysis of replicate specimens simulating clinical barbotage specimens, fixed to allow easy transportation and storage at room temperature was one specific objective. Simulated barbotage specimens were prepared by mixing cultured aneuploid bladder carcinoma cells with normal or mitogen-stimulated peripheral blood mononuclear cells in different ratios. The samples were fixed in 10% formalin for 30 minutes, stored in buffer, and enucleated with pepsin, pH 1.5, before staining with propidium iodide for FCM DNA analysis. Preservation in ethanol or other common DNA cytochemical reagents was found to be unsatisfactory. In contrast, the formalin-fixed samples showed excellent preservation of quantitative DNA fluorescence and coefficient of variation of histogram peaks for over 2 weeks. Exchange of eight fixed specimens among five network laboratories that analyzed them as "unknowns" showed good overall agreement on histogram data and interpretation, although some noteworthy interlaboratory differences were found. This technique could be used for self-assessment surveys of clinical laboratory performance in DNA FCM of bladder barbotage specimens. 相似文献
10.
This study analyses the influence of female and male patient age and human
menopausal gonadotrophin (HMG) requirements on clinical pregnancy rates and
live birth rates with ovulation stimulation using HMG in combination with
intrauterine insemination (IUI). In this study, 363 consecutive HMG/IUI
treatment cycles in 184 patients carried out at a university fertility
centre were analysed in a retrospective fashion. The main outcomes measured
were clinical pregnancy rates and live birth rates. Increased female
partner age (> or = 35) and male partner age (> or = 40) were found
to negatively influence pregnancy rates with HMG/ IUI therapy. In addition,
this study demonstrated a critical threshold of HMG requirements beyond
which pregnancy did not occur. No pregnancies occurred in treatment cycles
requiring > 25 ampoules (1875 IU) of menotrophins to achieve follicular
maturity, irrespective of patient age. In conclusion, female partner age,
male partner age, and HMG requirements all significantly influence
pregnancy rates with HMG/IUI therapy.
相似文献