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排序方式: 共有417条查询结果,搜索用时 15 毫秒
1.
Ittel TH; Steinhausen C; Kislinger G; Kinzel S; Nolte E; Sieberth HG 《Nephrology, dialysis, transplantation》1997,12(7):1369-1375
BACKGROUND: Developments in accelerator mass spectrometry (AMS) now permit
the determination of femtogram amounts of 26Al in blood and in various
tissues with good precision and free of external contamination. METHODS: In
the present study we used trace quantities of 26Al to investigate the
intestinal absorption and compartmentalization of aluminium in rats with
renal failure (Nx, 5/6 nephrectomy) and in pair- fed controls (C). Single
oral doses of 20 ng 26Al were administered to six animals in each group
and, subsequently, 24-h post-load 26Al was analysed in serum, urine, bone,
liver, and spleen by means of AMS. RESULTS: Serum concentrations of 26Al
were significantly lower in uraemic rats compared to controls, whereas
urinary excretion was comparable (Nx, 7.11 +/- 5.78 pg/day vs C, 9.46 +/-
6.10 pg/day), suggesting a higher fraction of ultrafiltrable serum 26Al in
uraemia. The target tissues of cellular transferrin-mediated 26Al uptake,
liver and spleen, tended to show a larger degree of aluminium accumulation
in controls (0.26 +/- 0.31 pg/g vs Nx, 0.14 +/- 0.10 pg/g and 0.37 +/- 0.27
pg/g vs Nx, 0.25 +/- 0.27 pg/g respectively). In contrast, in bone, a site
of extracellular aluminium deposition, 26Al concentrations were more
elevated in uraemia (1.22 +/- 0.59 pg/g vs C: 0.68 +/- 0.30 pg/g).
Estimated total 26Al accumulation in all measured target tissues was
significantly higher in uraemic rats (28.15 +/- 9.90 pg vs C: 17.03 +/-
7.03 pg) and total recovery of 26Al from tissue and urine was 26.58 +/-
6.74 pg in controls and 35.75 +/- 7.03 pg in uraemic animals, suggesting a
fractional absorption of 0.133% and 0.175% respectively. CONCLUSIONS: Our
data suggest that fractional absorption from a dietary level dose of 26Al
is about 0.13%. Compartmentalization occurs in transferrin-dependent target
tissues such as liver and spleen; however, in quantitative terms
extracellular deposition in bone is more important. Uraemia has a
significant effect on the intestinal absorption and compartmentalization of
aluminium. It enhances fractional absorption and increases subsequent
extracellular deposition of aluminium in bone. However, at the same time
uraemia does not increase transferrin-dependent cellular accumulation of
aluminium in liver and spleen.
相似文献
2.
Visual pigments from the red rods of adults of eight species of Australian anuran amphibians, from a variety of habitats, were analyzed by microspectrophotometry. The lambda max in all cases fell between 502 nm and 506 nm, and the absorption spectra were well fitted by an A1-based visual pigment template curve. Red rod pigments were also analyzed for a number of tadpoles. In some cases the data were best fitted with an A1-based visual pigment template, in other cases with an A2-based template, and finally some tadpoles appeared to have mixtures of the two pigments. 相似文献
3.
J Yasky MD M Verho MD TP Erasmus MMedSc HG Luus PhD M Angela MD L Grandin MD MA Akbary MD B Rangoonwala PhD 《International journal of clinical practice》1996,50(6):302-310
SUMMARY This double-blind, randomised, cross-over study investigated the antihypertensive efficacy of ramipril and enalapril was completed by 30 patients with mild-to-moderate essential hypertension. After a four-week placebo run-in phase, the patients received either 2.5mg ramipril or 10mg enalapril once daily for four weeks. The dosages were increased to 5mg ramipril and 20mg enalapril for a further four weeks. After a placebo washout phase of four weeks, the patients were crossed over to the alternative treatment. The decrease in average 24-hour ambulatory diastolic blood pressure from week 0 to week 8 was 1.6mmHg greater with ramipril than enalapril (90% confidence interval 0.6-2.7mmHg). The corresponding reduction in for systolic blood pressure was also greater with ramipril than enalapril by 2.4mmHg (90% confidence interval: 0.5-4.2mmHg). For the difference in the drop of 24-hour ambulatory diastolic blood pressure between ramipril and enalapril the lower level of the 90% confidence interval (CI) is above the clinically relevant difference of -3mmHg. This is an indication that ramipril (2.5 and 5mg dose) is at least as effective as enalapril (10 and 20mg dose) in decreasing blood pressure in patients with mild-to-moderate essential hypertension. The duration of adequate antihypertensive effect was relatively long for both ramipril and enalapril; however, ramipril tended to have a more prolonged antihypertensive effect. Ramipril had a higher diastolic and systolic trough/peak ratio than enalapril, resulting in a more uniform antihypertensive effect over the 24-hour treatment period. Both ramipril and enalapril were well tolerated and the two treatment groups had similar safety profiles. 相似文献
4.
Pre-B cells and other possible precursor lymphoid cell lines derived from patients with X-linked agammaglobulinemia 总被引:14,自引:6,他引:14 下载免费PDF全文
SM Fu JN Hurley JM McCune HG Kunkel RA Good 《The Journal of experimental medicine》1980,152(6):1519-1526
A group of unique Epstein-Barr virus-containing cell lines was derived from the bone marrow of three patients with X-linked agammaglobulinemia. Efforts to obtain cell lines from the peripheral blood of these patients were uniformly unsuccessful. Immunofluorescence analyses as well as biosynthetic studies with [(35)S]methionine indicated unusual patterns of Ig synthesis in many of these bone marrow derived lines. Seven of the lines were of particular interest in that two produced no Ig of any type; two others showed no Ig by fluorescence but small amounts by [(35)S]methionine labeling; one expressed only cytoplasmic μ chains without any evidence of light chain synthesis, and two produced primarily μ chains with only slight amounts of light chains. One of the lines without membrane or cytoplasmic Ig studied in detail grew like a typical lymphoid line and was carried in intermittent culture over a period of 2 yr without Ig expression. One line grew quite differently and resembled the round cell type described previously, which has been obtained from a variety of sources. The cell line with cytoplasmic μ chains and no light-chain expression had the characteristic properties of pre-B cells. Three normal type Ig-producing cell lines also were obtained from the patients. The accumulated evidence obtained in the present study indicates that these unusual cell lines represent normal precursor cells of the B-cell lineage; these grew out in these cases because of the virtual absence of mature B cells that ordinarily overgrow the culture system. However, the possibility that in certain instances they reflect abnormal Ig synthesis characteristic of the disease has not been ruled out. 相似文献
5.
目的:制备大鼠在体缺血再灌注模型,观察缺血预处理程序中心肌环磷酸腺苷含量及环磷酸腺苷依赖蛋白激酶活性的变化。方法:实验于2005-03/2006-10在解放军沈阳军区总医院医学实验动物中心和全军心血管研究所实验室完成。实验分组:选用健康雌性SD大鼠36只,根据预适应程序分为第1,2,3次缺血,第1,2,3次再灌注,每一时间点6只大鼠。实验过程:用手术套管法造成左冠状动脉主干缺血及再灌注。所有实验动物在实验程序结束后,取出心脏迅速置液氮保存备用。实验评估:用放射免疫法测环磷酸腺苷水平,生化法测环磷酸腺苷依赖蛋白激酶活性变化。结果:36只大鼠均进入结果分析。①环磷酸腺苷含量:第1次再灌注组低于第1次缺血组[(0.325±0.015),(0.395±0.024)pmol/g,t=6.06,P<0.001],第2次再灌注组低于第2次缺血组[(0.523±0.017),(0.708±0.067)pmol/g,t=6.56,P<0.001],第3次再灌注组低于第3次缺血组[(0.567±0.031),(0.712±0.038)pmol/g,t=7.24,P<0.001]。②环磷酸腺苷依赖蛋白激酶活性:第1次再灌注组低于第1次缺血组[(10.115±1.000),(16.351±0.849)pkat/g,t=11.12,P<0.001],第2次再灌注组低于第2次缺血组[(11.877±2.213),(14.869±0.619)pkat/g,t=3.31,P<0.01],第3次再灌注组低于第3次缺血组[(11.745±0.987),(14.766±0.329)pkat/g,t=7.09,P<0.001]。③缺血预处理程序中心肌环磷酸腺苷含量及环磷酸腺苷依赖蛋白激酶活性随缺血及再灌注呈周期性波动。在5min缺血预处理时表现为明显增高,而在间隔的再灌注程序中恰呈相反改变,有明显下降的趋势。结论:环磷酸腺苷及环磷酸腺苷依赖蛋白激酶的周期性波动变化可能是激发心肌缺血预处理的机制之一,环磷酸腺苷可能在预处理保护作用中起一些作用。 相似文献
6.
股方肌肌骨瓣植入治疗成人股骨头缺血性坏死 总被引:1,自引:0,他引:1
目的:目前成人股骨头缺血性坏死的手术方法较多,但远期疗效大多不肯定。股方肌肌骨瓣植入术可以治疗成人股骨头缺血性坏死,但需验证其近远期疗效。方法:选择2001-01/2007-01铜川市矿务局中心医院骨科收治的股方肌肌骨瓣植入治疗股骨头坏死患者15例(18髋),均知情同意。术中暴露股方肌及其在股骨近端的附着点,于附着点处凿取骨瓣,骨瓣为4cm×1.5cm×1.0cm的长方形,将骨瓣插入股骨头内,远端用可吸收骨钉固定。术后3,6,12,24个月门诊复查拍患髋正位和蛙式位X射线片,根据临床查体和X射线片表现将手术效果分为优、良、差3级。结果:全部患者均获随访,随访时间4~36个月。近期疗效满意,出院时疼痛症状均缓解,未见手术相关并发症。中远期随访结果优10髋,良6髋,差2髋,优良率88.9%。结论:股方肌肌骨瓣植入术治疗成人股骨头缺血性坏死近远期疗效确切,手术操作相对简单。 相似文献
7.
Mandy B Belfort John AF Zupancic Katherine M Riera Jane HG Turner Lisa A Prosser 《BMC pediatrics》2011,11(1):12
Background
Childhood obesity is a substantial public health problem. The extent to which health state preferences (utilities) are related to a child's weight status has not been reported. The aims of this study were (1) to use a generic health state classification system to measure health related quality of life and calculate health utilities in a convenience sample of children and adolescents and (2) to determine the extent to which these measures are associated with weight status and body mass index (BMI). 相似文献8.
9.
Barbara A. Goff Ricardo Sainz de la Cuesta Howard G. Muntz Deborah Fleischhacker Marit Ek Laurel W. Rice Najmosama Nikrui Hisham K. Tamimi Joanna M. Cain Benjamin E. Greer Arlan F. Fuller Jr. 《Gynecologic oncology》1996,60(3):412-417
Between 1982 and 1992, 24 women with Stage III clear cell ovarian cancer were identified from the tumor registry. Thirty-four women with Stage III papillary serous tumors treated between 1987 and 1989 were used as a comparison. All patients underwent cytoreductive surgery followed by conventional platinum-based chemotherapy. In the women with clear cell histology, nine (37.5%) had endometriosis in the surgical specimen compared with one (3%) in the papillary serous group (P= 0.002). Ten women (42%) with clear cell histology experienced a thromboembolic event during the course of treatment, compared to six (18%) in the papillary serous group (P= 0.05). In the group with clear cell histology, overall, 70% of women had progressive disease. Fifty-two percent experienced clinical progression while receiving platinum-based chemotherapy. In addition, four patients were found to have progressive disease at second-look laparotomy. Only two patients had a pathologic complete response. In the group with papillary serous histology, 29% overall had progressive disease while on chemotherapy (P= 0.005). The median survival for the women with clear cell histology was 12 months compared to 22 months for those with papillary serous (P= 0.02). For women with clear cell histology, univariate analysis was used to evaluate prognostic factors. Age less than 50 was a poor prognostic factor (P= 0.045). The presence of endometriosis, thromboembolic event, or optimal cytoreduction were not prognostic factors (P= 0.67,P= 0.34,P= 0.39). Patients with advanced clear cell ovarian cancer have a poor response to conventional platinum-based chemotherapy and overall prognosis is poor. 相似文献
10.
H G Muntz 《Gynecologic oncology》1999,74(3):456-459
OBJECTIVE: The aim of this article is to evaluate the nature and frequency of informal "curbside" consultations in a gynecologic oncology practice. METHODS: A log of all curbside consultations requested from a gynecologic oncologist in a tertiary multispecialty group practice was kept for 2 years (July 1996 to June 1998). New referrals or calls concerning mutual patients were excluded. RESULTS: Three hundred thirty-three requests for advice were received from 87 different physicians. Most (81%) of the calls were from 51 obstetrician/gynecologists (Ob/Gyns); 13% of the calls were from family practitioners or general internists. The four most common topics discussed were lower genital tract dysplasia (18%), endometrial hyperplasia (17%), adnexal masses (11%), and endometrial cancer (10%). Overall, 29% of questions pertained to the management of an invasive gynecologic malignancy. Twenty-four percent of the questions were answered in less than 5 min, 43% in 5-10 min, 29% in 11-20 min, and 4% in over 20 min. The issues discussed were considered simple in 26%, of moderate complexity in 49%, very complex in 22%, and ultracomplex in 3%. One hundred nine questions (33%) were of sufficient complexity to warrant referral to a specialist, which occurred in 52 cases (48%); physicians employed by a staff-model health maintenance organization were less likely to request a formal consultation (14%, chi(2) = 0.001). CONCLUSIONS: Curbside consultations are a frequent occurrence in the practice of a gynecologic oncologist, with most questions posed by general Ob/Gyns. Approximately one-third of the questions were of minimal complexity and involved topics covered in standard textbooks or residency training programs. In contrast, approximately one-third were of sufficient complexity that a casual discussion between colleagues may not yield optimal medical care. 相似文献