全文获取类型
收费全文 | 460篇 |
免费 | 31篇 |
国内免费 | 15篇 |
专业分类
耳鼻咽喉 | 1篇 |
儿科学 | 31篇 |
妇产科学 | 6篇 |
基础医学 | 63篇 |
口腔科学 | 7篇 |
临床医学 | 62篇 |
内科学 | 81篇 |
皮肤病学 | 18篇 |
神经病学 | 17篇 |
特种医学 | 86篇 |
外科学 | 32篇 |
综合类 | 35篇 |
预防医学 | 18篇 |
眼科学 | 1篇 |
药学 | 20篇 |
肿瘤学 | 28篇 |
出版年
2023年 | 2篇 |
2022年 | 1篇 |
2021年 | 2篇 |
2020年 | 1篇 |
2019年 | 7篇 |
2018年 | 6篇 |
2017年 | 7篇 |
2016年 | 7篇 |
2015年 | 8篇 |
2014年 | 11篇 |
2013年 | 16篇 |
2012年 | 11篇 |
2011年 | 13篇 |
2010年 | 19篇 |
2009年 | 31篇 |
2008年 | 22篇 |
2007年 | 20篇 |
2006年 | 21篇 |
2005年 | 16篇 |
2004年 | 8篇 |
2003年 | 6篇 |
2002年 | 11篇 |
2001年 | 15篇 |
2000年 | 9篇 |
1999年 | 17篇 |
1998年 | 38篇 |
1997年 | 30篇 |
1996年 | 14篇 |
1995年 | 17篇 |
1994年 | 15篇 |
1993年 | 16篇 |
1992年 | 10篇 |
1991年 | 6篇 |
1990年 | 7篇 |
1989年 | 7篇 |
1988年 | 5篇 |
1987年 | 7篇 |
1986年 | 3篇 |
1985年 | 12篇 |
1984年 | 2篇 |
1983年 | 7篇 |
1982年 | 4篇 |
1981年 | 6篇 |
1980年 | 5篇 |
1978年 | 1篇 |
1977年 | 2篇 |
1976年 | 2篇 |
1975年 | 2篇 |
1955年 | 1篇 |
排序方式: 共有506条查询结果,搜索用时 15 毫秒
1.
Transfusion-related acute lung injury caused by an NB2 granulocyte- specific antibody in a patient with thrombotic thrombocytopenic purpura 总被引:3,自引:0,他引:3
HLA and granulocyte-specific antibodies have been implicated in the production of transfusion-related acute lung injury (TRALI). Reported here is a case that suggests that the patient's preexisting condition may play an important role in determining whether TRALI develops upon transfusion of blood products containing anti-white cell (WBC) antibodies. A 29-year-old woman with thrombotic thrombocytopenic purpura (TTP) underwent an uneventful 1.5-volume plasma exchange, which was followed by the transfusion of 2 red cell (RBC) units. At the end of the second RBC transfusion, the patient developed clinical signs and symptoms of noncardiogenic pulmonary edema. Serologic studies demonstrated that the serum from the second RBC donor had no HLA antibodies but did have a granulocyte-specific antibody (anti-NB2) that caused the agglutination of the recipient's granulocytes, which were NB2 positive. Serum from the donor of the first RBC unit and serum from the donors of units used in the exchange had no HLA or granulocyte-specific antibodies that reacted with the recipient's WBCs. Because the donor implicated in this reaction had a history of 21 blood donations, none of which had been associated with a transfusion reaction, we suggest that the patient's preexisting condition played a significant role in this episode of TRALI, owing to the granulocyte-specific antibody. 相似文献
2.
Sudden infant death syndrome and diphtheria-tetanus-pertussis-poliomyelitis vaccination status 总被引:1,自引:0,他引:1
Summary— Because diphtheria, tetanus, pertussis and poliomyelitis vaccine is routinely given during the period of highest incidence of sudden infant death syndrome (SIDS), we carried out a retrospective case-control study to assess whether such vaccination increased the risk of SIDS. The vaccination status of 118 SIDS and 332 control children, matched for sex, date of birth and age of the victims at death, was compared: the victims of SIDS were not significantly more often vaccinated than control children, the odds ratio was estimated at 1.9 with a 95% confidence interval from 0.9 to 3.9. There was a statistical difference between vaccination status of SIDS cases and controls aged less than three months. Nine percent of SIDS cases under 3 months had been vaccinated whereas the matched controls had not. In our study DTCP vaccination was not a risk factor for SIDS; although more of the SIDS infants less than 3 months of age had been vaccinated. This result however, concerns only one subgroup of the population studied and needs to be confirmed with another study of only SIDS infants less than 3 months of age, because DTCP vaccination was not a risk factor for SIDS when considering the total sample of the study. 相似文献
3.
Mycobacterial Infections After Renal Transplantation 总被引:5,自引:0,他引:5
HIGGINS RM; CAHN AP; PORTER D; RICHARDSON AJ; MITCHELL RG; HOPKIN JM; MORRIS PJ 《QJM : monthly journal of the Association of Physicians》1991,78(2):145-153
Mycobacterial infections occurred in 11 of 633 (1.7 per cent)recipients of successful renal transplants. There were no casesof tuberculosis in patients receiving chemoprophylaxis, butamongst those who did not receive prophylaxis disease occurredin six of the 27 (22 per cent) high-risk patients. The majorcause of morbidity during treatment was renal allograft rejection,largely due to reduction in immunosuppressive drug therapy. 相似文献
4.
5.
Bone marrow transplantation for patients with Philadelphia chromosome- positive acute lymphoblastic leukemia 总被引:1,自引:2,他引:1
Forman SJ; O'Donnell MR; Nademanee AP; Snyder DS; Bierman PJ; Schmidt GM; Fahey JL; Stein AS; Parker PM; Blume KG 《Blood》1987,70(2):587-588
We report the treatment outcome of allogeneic bone marrow transplantation in ten patients with Philadelphia chromosome-positive acute lymphoblastic leukemia. Six patients are alive and well for 6 to 30 months (median 19 months) after transplantation. Four patients died with transplant related complications. In view of the poor prognosis associated with this disease, marrow ablation followed by allogeneic or syngeneic marrow grafting may be the preferred treatment modality if a suitable marrow donor is available. 相似文献
6.
Comparison of clinical and self-reported diagnoses for participants on a community-based arthritis self-management programme 总被引:2,自引:0,他引:2
OBJECTIVE: With the advent of community-based arthritis education
programmes, it is important to determine the accuracy of participants'
self-reported diagnoses. The purpose of this study was to determine the
level of agreement between general practitioner (GP)-recorded and self-
reported diagnoses of participants attending an Arthritis Self- Management
Programme (ASMP). METHODS: Participants enrolling on the ASMP were asked to
(a) identify their type of arthritis via a self- administered postal
questionnaire and (b) obtain a written confirmation of their diagnosis from
their GP. The sample (n = 613) comprised mainly women (83%) with a mean age
of 58.8 yr (S.D. 12.6) and a mean disease duration of 15.4 yr (S.D. 12.5).
RESULTS: Participants' self-reported diagnoses were confirmed by GPs in 534
cases [87.1%, 95% confidence interval (CI): 84.4 89.8%]. Confirmed
diagnoses were reported by 86.9% (95% CI: 83.1-90.7%) of those with
osteoarthritis (OA) and 96.1% (95% CI: 93.6 98.6%) of those with rheumatoid
arthritis (RA). The concordance rate for all other types of arthritis
combined was lower at 60.5% (95% CI: 49.5-71.5%). There were no significant
differences with respect to age, gender, education, physical functioning,
duration of disease and number of GP visits between those who correctly
identified their type of arthritis and those who did not. CONCLUSIONS: This
study suggests that the majority of RA and OA participants attending an
arthritis education programme can correctly identify their specific type of
arthritis.
相似文献
7.
8.
Hellmut Merkle Joseph Murphy‐Boesch Peter van Gelderen Shumin Wang Tie‐Qiang Li Alan P. Koretsky Josef H. Duyn 《Magnetic resonance in medicine》2011,66(3):901-910
When volume coils are used for 1H imaging of the human head at 7T, wavelength effects in tissue cause a variation in intensity, that is typically brighter at the center of the head and darker in the periphery. Much of this image nonuniformity can be attributed to variation in the effective transmit B1 field, which falls by ~ 50% to the left and right of center at mid‐elevation in the brain. Because most of this B1 loss occurs in the periphery of the brain, we have explored use of actively controlled, off‐resonant loop elements to locally enhance the transmit B1 field in these regions. When tuned to frequencies above the NMR frequency, these elements provide strong local enhancement of the B1 field of the transmit coil. Because they are tuned off‐resonance, some volume coil detuning results, but resistive loading of the coil mode remains dominated by the sample. By digitally controlling their frequency offsets, the field enhancement of each inner element can be placed under active control. Using an array of eight digitally controlled elements placed around a custom‐built head phantom, we demonstrate the feasibility of improving the B1 homogeneity of a transmit/receive volume coil without the need for multiple radio frequency transmit channels. Magn Reson Med, 2011. © 2011 Wiley‐Liss, Inc. 相似文献
9.
Duyn JH van Gelderen P Li TQ de Zwart JA Koretsky AP Fukunaga M 《Proceedings of the National Academy of Sciences of the United States of America》2007,104(28):11796-11801
The ability to detect brain anatomy and pathophysiology with MRI is limited by the contrast-to-noise ratio (CNR), which depends on the contrast mechanism used and the spatial resolution. In this work, we show that in MRI of the human brain, large improvements in contrast to noise in high-resolution images are possible by exploiting the MRI signal phase at high magnetic field strength. Using gradient-echo MRI at 7.0 tesla and a multichannel detector, a nominal voxel size of 0.24 x 0.24 x 1.0 mm3 (58 nl) was achieved. At this resolution, a strong phase contrast was observed both between as well as within gray matter (GM) and white matter (WM). In gradient-echo phase images obtained on normal volunteers at this high resolution, the CNR between GM and WM ranged from 3:1 to 20:1 over the cortex. This CNR is an almost 10-fold improvement over conventional MRI techniques that do not use image phase, and it is an approximately 100-fold improvement when including the gains in resolution from high-field and multichannel detection. Within WM, phase contrast appeared to be associated with the major fiber bundles, whereas contrast within GM was suggestive of the underlying layer structure. The observed phase contrast is attributed to local variations in magnetic susceptibility, which, at least in part, appeared to originate from iron stores. The ability to detect cortical substructure from MRI phase contrast at high field is expected to greatly enhance the study of human brain anatomy in vivo. 相似文献
10.
Grigg AP; Roberts AW; Raunow H; Houghton S; Layton JE; Boyd AW; McGrath KM; Maher D 《Blood》1995,86(12):4437-4445
To define an optimal regimen for mobilizing and collecting peripheral blood progenitor cells (PBPC) for use in allogeneic transplantation, we evaluated the kinetics of mobilization by filgrastim (recombinant met- human granulocyte colony-stimulating factor [r-metHuG-CSF]) in normal volunteers. Filgrastim was injected subcutaneously for up to 10 days at a dose of 3 (n = 10), 5 (n = 5), or 10 micrograms/kg/d (n = 15). A subset of volunteers from each dose cohort underwent a 7L leukapheresis on study day 6 (after 5 days of filgrastim). Granulocyte-macrophage colony-forming cell (GM-CFC) numbers in the blood were maximal after 5 days of filgrastim; a broader peak was evident for CD34+ cells between days 4 and 6. The 95% confidence intervals (CI) for mean number of PBPC per milliliter of blood in the three dose cohorts overlapped on each study day. However, on the peak day, CD34+ cells were significantly higher in the 10 micrograms/kg/d cohort than in a pool of the 3 and 5 micrograms/kg/d cohorts. Mobilization was not significantly influenced by volunteer age or sex. Leukapheresis products obtained at the 10 micrograms/kg/d dose level contained a median GM-CFC number of 93 x 10(4)/kg (range, 50 x 10(4)/kg to 172 x 10(4)/kg). Collections from volunteers receiving lower doses of filgrastim contained a median GM- CFC number of 36 x 10(4)/kg (range, 5 x 10(4)/kg to 204 x 10(4)/kg). The measurement of CD34+ cells per milliliter of blood on the day of leukapheresis predicted the total yield of PBPC in the leukapheresis product (r = .87, P < .0001). Assuming a minimum GM-CFC requirement of 50 x 10(4)/kg (based on our experience with autologous PBPC transplantation), all seven leukapheresis products obtained at the 10 micrograms/kg/d dose level were potentially sufficient for allogeneic transplantation purposes. We conclude that in normal donors, filgrastim 10 micrograms/kg/d for 5 days with a single leukapheresis on the following day is a highly effective regimen for PBPC mobilization and collection. Further studies are required to determine whether PBPC collected with this regimen reliably produce rapid and sustained engraftment in allogeneic recipients. 相似文献