全文获取类型
收费全文 | 25422篇 |
免费 | 1671篇 |
国内免费 | 302篇 |
专业分类
耳鼻咽喉 | 523篇 |
儿科学 | 378篇 |
妇产科学 | 396篇 |
基础医学 | 4005篇 |
口腔科学 | 327篇 |
临床医学 | 2030篇 |
内科学 | 5382篇 |
皮肤病学 | 780篇 |
神经病学 | 1895篇 |
特种医学 | 1414篇 |
外科学 | 3576篇 |
综合类 | 139篇 |
现状与发展 | 1篇 |
一般理论 | 13篇 |
预防医学 | 1186篇 |
眼科学 | 860篇 |
药学 | 2208篇 |
中国医学 | 259篇 |
肿瘤学 | 2023篇 |
出版年
2023年 | 155篇 |
2022年 | 474篇 |
2021年 | 768篇 |
2020年 | 394篇 |
2019年 | 638篇 |
2018年 | 785篇 |
2017年 | 574篇 |
2016年 | 892篇 |
2015年 | 1147篇 |
2014年 | 1351篇 |
2013年 | 1498篇 |
2012年 | 2297篇 |
2011年 | 2237篇 |
2010年 | 1332篇 |
2009年 | 1137篇 |
2008年 | 1500篇 |
2007年 | 1482篇 |
2006年 | 1264篇 |
2005年 | 1233篇 |
2004年 | 1042篇 |
2003年 | 830篇 |
2002年 | 769篇 |
2001年 | 434篇 |
2000年 | 403篇 |
1999年 | 352篇 |
1998年 | 164篇 |
1997年 | 119篇 |
1996年 | 114篇 |
1995年 | 98篇 |
1994年 | 82篇 |
1993年 | 67篇 |
1992年 | 177篇 |
1991年 | 178篇 |
1990年 | 150篇 |
1989年 | 177篇 |
1988年 | 127篇 |
1987年 | 137篇 |
1986年 | 108篇 |
1985年 | 91篇 |
1984年 | 73篇 |
1983年 | 54篇 |
1982年 | 36篇 |
1981年 | 37篇 |
1980年 | 37篇 |
1979年 | 48篇 |
1978年 | 32篇 |
1977年 | 35篇 |
1975年 | 34篇 |
1974年 | 32篇 |
1973年 | 29篇 |
排序方式: 共有10000条查询结果,搜索用时 171 毫秒
21.
R. J. Bosma A. J. Kwakernaak J. J. Homan van der Heide P. E. de Jong G. J. Navis 《American journal of transplantation》2007,7(3):645-652
Obesity is a risk factor for renal graft loss. Higher body mass index (BMI) in native kidneys is associated with glomerular hyperfiltration. Whether higher BMI in renal transplants is associated with hyperfiltration is unknown. We investigated the impact of BMI on renal hemodynamics 1 year post-transplant. We analyzed glomerular filtration rate (GFR, (125)I-iothalamate) and effective renal plasma flow (ERPF, (131)I-hippurate) in 838 kidney transplants. Data were analyzed for all patients and for the subpopulation without diabetes. Long-term impact of BMI and renal hemodynamics were explored by Cox-regression. With higher BMI GFR and filtration fraction (FF) increased significantly. Multivariate analysis supported impact of BMI on GFR (adjusted r(2) of the model 0.275) and FF (adjusted r(2) of the model 0.158). This association was not explained by diabetes mellitus. On Cox-regression analysis, lower GFR and higher FF were independent determinants of overall graft loss and graft loss by patient mortality. Lower GFR and higher BMI were determinants of death-censored graft loss, with borderline contribution of higher FF. In renal transplants higher BMI is independently associated with higher GFR and FF one year posttransplant, suggesting glomerular hyperfiltration with altered afferent-efferent balance. Mechanisms underlying the long-term prognostic impact of hyperfiltration deserve further exploration. 相似文献
22.
Eun Young Jung Hyung Joo Suh Wan Soo Hong Dong Geon Kim Yang Hee Hong In Sun Hong Un Jae Chang 《Nutrition Research》2009,29(7):457-461
Cooking processes that gelatinize granules or disrupt structure might increase the glucose and insulin responses because a disruption of the structure of starch by gelatinization increases its availability for digestion and absorption in the small intestine. We hypothesized that the uncooked form of rice, which has a relatively low degree of gelatinization even though in powder form, would result in lower metabolic glucose and insulin responses compared with cooked rice (CR). To assess the effects of the gelatinization of rice on metabolic response of glucose and insulin, we investigated the glucose and insulin responses to 3 rice meals of different gelatinization degree in female college students (n = 12): CR (76.9% gelatinized), uncooked rice powder (UP; 3.5% gelatinized), and uncooked freeze-dried rice powder (UFP; 5.4% gelatinized). Uncooked rice powders (UP and UFP) induced lower glucose and insulin responses compared with CR. The relatively low gelatinization degree of UPs resulted in low metabolic responses in terms of the glycemic index (CR: 72.4% vs UP: 49.7%, UFP: 59.8%) and insulin index (CR: 94.8% vs UP: 74.4%, UFP: 68.0%). In summary, UPs that were less gelatinized than CR induced low postprandial glucose and insulin responses. 相似文献
23.
Hilde Tobi Paul B. van den Berg Lolkje TW de Jong‐van den Berg 《Pharmacoepidemiology and drug safety》2006,15(3):211-211
The original article to which this Erratum refers was published in Pharmacoepidemiology and Drug Safety 2005; 14: 239–247. 相似文献
24.
BACKGROUND. A health risk appraisal (HRA) is a tool for health promotion. Conversational microcomputer-based HRAs may be more cost effective than other HRA formats. The acceptability of conversational HRAs, however, has not been demonstrated for older adults. METHODS. We studied the acceptability of a conversational microcomputer-based HRA in a sample of 247 adults at the Minnesota State Fair and the Senior Options Exposition. All users were offered the appraisal via mouse or keyboard interface. Acceptability was measured in terms of user-reported helpfulness, intent to change, time of use, and willingness to view HRA health recommendations. Data on completion time and willingness to view HRA recommendations were collected for Senior Exposition users only. Regression analyses were used to examine the combined impact of interface (mouse or keyboard), location (State Fair or Senior Exposition), age, and sex on user acceptability. Results. Interface and location had no effect on helpfulness or change ratings. Older users rated the appraisal more helpful (P less than .007). Both older and female users reported more intent to change behavior (P = .016, both). Time to use the appraisal was related to interface, age, and sex. Mouse users (P less than .0001), older users (P less than .0001) and female users (P less than .05) took significantly longer to use the appraisal. Significantly more mouse users declined to see recommendations (P less than .02). CONCLUSIONS. Older users can derive as much or more value from conversational health risk appraisals as younger users; however, a mouse interface may be less effective for this age group. 相似文献
25.
26.
Clinical pharmacokinetics of midazolam in intensive care patients, a wide interpatient variability? 总被引:7,自引:0,他引:7
H Oldenhof M de Jong A Steenhoek R Janknegt 《Clinical pharmacology and therapeutics》1988,43(3):263-269
The pharmacokinetics of midazolam and its metabolites were studied in 17 patients on mechanical ventilation in a general intensive care unit who were receiving a continuous intravenous infusion of midazolam, adjusted according to the level of induced sedation. Three patients were studied twice. Serum midazolam and alpha-hydroxymidazolamglucuronide levels were determined during and after infusion. The sedation level was scored on a four-point scale. Half of the observed patients were still drowsy or asleep 10 hours after termination of midazolam infusion. In only one patient was midazolam serum elimination half-life less than 2 hours and in six patients the half-life was greater than 10 hours. A wide range of midazolam serum levels was associated with adequate sedation, and similarly the midazolam levels at the moment of awakening were highly variable. The serum concentration ratio of midazolam/alpha-hydroxymidazolamglucuronide at the end of the infusion varied from 0.03 to 15.6. Renal function could account for only a part of this variation. 相似文献
27.
Jung Han Kim Sang Jun Lee Young Bok Han Jung Jo Moon Jong Bae Kim 《Archives of pharmacal research》1994,17(2):115-118
This paper describes the isolation of isoguanosine from Croton tiglium L. and its cytotoxic effect against several tumor cell lines in culture and newly reports that isoguanosine has an antitumor activity against implanted S-180 ascitic tumor mice. Isoguanosine is effective at the dose of 24 mg/kg/day x 5, with T/C value of 168%. Isoguanosine inhibits the growth of S-180 and Ehrlich solid tumor in mice at the optimal doses of 96 mg/kg/day x 12 and 48 mg/kg/day x 12, with 1-T/C values of 65% and 60%, respectively. 相似文献
28.
29.
Navis G. J.; Dullaart R. P. F.; Vellenga E.; Elema J. D.; de Jong P. E 《Nephrology, dialysis, transplantation》1994,9(10):1477-1481
POEMS syndrome is a multisystem disorder associated with plasmacell dyscrasias. This report describes a patient with POEMS-associatedrenal disease and reviews the literature on biopsy-proven renalinvolvement in POEMS syndrome. Our patient had glomerulonephritiswith membranoproliferative features on light-microscopy withoutcharacteristic findings on immunofluorescence, and with ultra-structural evidence of glomerular microangiopathy. Ultrastructuralevidence of microangiopathy was also found in vasa nervorum.In 20 other cases of POEMS- associated renal disease, 16 hadglomerular disease. Light-microscopy showed membranoproliferative-likeglomerulopathy in 14 patients and glomerular microan giopathyin two. Ultrastructural evidence of microangi opathy was presentin all 15 patients in whom electron- microscopy was done. Thus,in most patients with POEMS-associated glomerular disease acharacteristic lesion is present with evidence of endothelialinjury. As endothelial damage is also found in endoneural vessels,generalized endothelial injury may play a role in non-renalmanifestations of POEMS syndrome. In previous reviews manifestationsof the POEMS syndrome were similar for patients with or withoutmyeloma. Among patients with biopsy-proven glomerular disease,however, myeloma patients are underrepres ented. Whether thisrepresents a sampling error or has true pathophysiological significanceremains to be established. 相似文献
30.
Kyung Bok Lee Jong Sig Kim Sang Tae Kwak Wonbo Sim Jong Hwan Kwak Yeong Shik Kim 《Archives of pharmacal research》1998,21(5):555-558
Chondroitin sulfates were isolated from the mud snail. For the quantitative analysis of enzymatic digestion products of isolated
chondroitin sulfates, strong anion exchange-high performance liquid chromatography (SAX-HPLC) was performed. By the action
of chondroitinase ABC, three unsaturated disaccharides 2-acetamide-2-deoxy-3-O-(β-D-gluco-4-enepyranosyluronic acid)-D-galactose (ΔDi-OS), 2-acetamide-2-deoxy-3-O-(β-D-gluco-4-enepyranosyluronic acid)-6-O-sulfo-D-galactose (ΔDi-6S) and 2-acetamide-2-deoxy-3-O-(β-D-gluco-4-enepyranosyluronic acid)-4-O-sulfo-D-galactose (ΔDi-4S) were produced from the mud snail chondroitin sulfates. The analysis showed that relative proportion
of ΔDi-OS/ΔDi-6S/ΔDi-4S was 58.7/3.1/38.2. The immunomodulating activity of chondroitin sulfate was examined by cell proliferation
assay and these results suggest that it might be a immunosuppressant. 相似文献