全文获取类型
收费全文 | 930篇 |
免费 | 39篇 |
国内免费 | 47篇 |
专业分类
耳鼻咽喉 | 33篇 |
儿科学 | 43篇 |
妇产科学 | 5篇 |
基础医学 | 114篇 |
口腔科学 | 50篇 |
临床医学 | 100篇 |
内科学 | 234篇 |
皮肤病学 | 26篇 |
神经病学 | 30篇 |
特种医学 | 161篇 |
外科学 | 53篇 |
综合类 | 24篇 |
一般理论 | 1篇 |
预防医学 | 11篇 |
眼科学 | 9篇 |
药学 | 60篇 |
中国医学 | 3篇 |
肿瘤学 | 59篇 |
出版年
2023年 | 2篇 |
2022年 | 2篇 |
2021年 | 7篇 |
2020年 | 3篇 |
2019年 | 4篇 |
2018年 | 7篇 |
2017年 | 10篇 |
2016年 | 10篇 |
2015年 | 23篇 |
2014年 | 22篇 |
2013年 | 31篇 |
2012年 | 17篇 |
2011年 | 22篇 |
2010年 | 39篇 |
2009年 | 38篇 |
2008年 | 18篇 |
2007年 | 60篇 |
2006年 | 21篇 |
2005年 | 25篇 |
2004年 | 30篇 |
2003年 | 18篇 |
2002年 | 31篇 |
2001年 | 29篇 |
2000年 | 20篇 |
1999年 | 17篇 |
1998年 | 50篇 |
1997年 | 50篇 |
1996年 | 57篇 |
1995年 | 32篇 |
1994年 | 34篇 |
1993年 | 20篇 |
1992年 | 13篇 |
1991年 | 12篇 |
1990年 | 9篇 |
1989年 | 33篇 |
1988年 | 32篇 |
1987年 | 21篇 |
1986年 | 22篇 |
1985年 | 15篇 |
1984年 | 17篇 |
1983年 | 11篇 |
1982年 | 15篇 |
1981年 | 11篇 |
1980年 | 14篇 |
1979年 | 5篇 |
1978年 | 6篇 |
1977年 | 7篇 |
1976年 | 6篇 |
1975年 | 8篇 |
1939年 | 2篇 |
排序方式: 共有1016条查询结果,搜索用时 296 毫秒
21.
22.
23.
24.
MUHAMMAD N RAZA MUHAMMAD HADID CHARLES E KEEN CORALIE BINGHAM ANDREW HJ SALMON 《Nephrology (Carlton, Vic.)》2012,17(8):748-753
Background: The use and timing of steroids in the management of acute tubulointerstitial nephritis (ATIN) remains debatable. Aims: To determine the incidence and aetiology of ATIN in our unit, and to examine trends in the use of steroids and their impact on renal outcomes. Methods: Patients with a histological diagnosis of ATIN over a 9‐year period were identified and divided into steroid‐treated (StG) and steroid‐naïve groups (SnG). Mean change in estimated glomerular filtration rate (eGFR) was determined. Results: Forty‐nine patients had ATIN as their main diagnosis, 67% of cases were drug‐induced, and proton pump inhibitors (PPI) were the second commonest implicated drug category. Majority (75%) of patients received steroids, and eGFR improved to a significantly greater degree in these steroid‐treated patients (3.4‐fold improvement vs 2.0‐fold in SnG; P < 0.05, unpaired t‐test). Despite comparable eGFR at presentation (StG: 11.7; SnG: 15.4), steroid‐treated patients were less likely to receive dialysis, although not significantly so (OR 0.27; 95% CI 0.06–1.15, P = 0.066, chi‐squared test). However, there was no significant relation between the degree of eGFR improvement and delay in starting steroids (Pearson r = ?0.25, P > 0.45), and no difference in eGFR at the time of last follow‐up (StG: 33 ± 3; SnG: 32 ± 7; P > 0.9, unpaired t‐test). Conclusion: StG patients had a greater degree of improvement in renal function, but with no correlation between degree of improvement in eGFR and delay in starting steroids, and similar eGFR values at final follow‐up. PPI were the second commonest drug category among drug‐induced cases. 相似文献
25.
26.
Expression of fibrinogen receptors during activation and subsequent desensitization of human platelets by epinephrine 总被引:2,自引:0,他引:2
Epinephrine causes platelet aggregation and secretion by interacting with alpha 2-adrenergic receptors on the platelet surface. Platelet aggregation requires the binding of fibrinogen to a specific receptor on the membrane glycoprotein IIb-IIIa complex. Although the IIb-IIIa complex is identifiable on the surface of resting platelets, the fibrinogen receptor is expressed only after platelet activation. The current studies were designed to examine the effect of occupancy of platelet alpha 2-adrenergic receptors by epinephrine on the expression of fibrinogen receptors and on the aggregation of platelets. The ability of epinephrine to induce the expression of fibrinogen receptors was studied under two different conditions: acute stimulation (less than 1 min) and prolonged stimulation (50 to 90 min), the latter of which is associated with a reduction or "desensitization" of the platelet aggregation response. Expression of the fibrinogen receptor was monitored with 125I-fibrinogen as well as with 125I-PAC-1 (PAC-1), a monoclonal antibody that binds to the glycoprotein IIb-IIIa complex only after platelets are activated. Epinephrine caused an immediate increase in PAC-1 and fibrinogen binding that was dependent on occupancy of the alpha 2-receptor by epinephrine and on the presence of extracellular free Ca (KCa = 30 mumol/L). By itself, 1 mmol/L Mg was unable to support induction of the fibrinogen receptor by epinephrine. However, it did decrease the Ca requirement by about two orders of magnitude. Prolonged stimulation of unstirred platelets by epinephrine led to a 70% decrease in the aggregation response when the platelets were subsequently stirred. Despite their decreased aggregation response, desensitized platelets bound PAC-1 and fibrinogen normally, indicating that the loss of aggregation was not due simply to a decrease in fibrinogen receptor expression. Although desensitization was not affected by pretreatment of the platelets with aspirin, it was partially prevented when extracellular Ca was chelated by EDTA during the long incubation with epinephrine. These studies demonstrate that once platelet alpha 2-adrenergic receptors are occupied by epinephrine, extracellular Ca is involved in initiating the aggregation response by supporting the induction of the fibrinogen receptor and the binding of fibrinogen. Furthermore. Ca-dependent reactions subsequent to fibrinogen binding may be necessary for maximal platelet aggregation and are impaired when platelets become desensitized to epinephrine. 相似文献
27.
Engraftment of dogs with Ia-positive marrow cells isolated by avidin- biotin immunoadsorption 总被引:3,自引:0,他引:3
Berenson RJ; Bensinger WI; Kalamasz D; Schuening F; Deeg HJ; Graham T; Storb R 《Blood》1987,69(5):1363-1367
Previous work has shown failure of engraftment in lethally irradiated dogs when autologous marrow was depleted of Ia-positive cells with an anti-Ia antibody and complement before infusion. In the current study, we have utilized an avidin-biotin immunoadsorption procedure to obtain a population of highly enriched Ia-positive cells for autologous bone marrow transplantation in dogs given lethal irradiation. Dog marrow cells (2.4 to 7.0 X 10(9) cells) that contained 8.6% to 19.9% Ia- positive cells were treated successively with monoclonal antibody 7.2, which reacts with a framework determinant of Ia-antigen, and biotin- conjugated goat antimouse immunoglobulin. These treated cells were passed over a column of avidin-Biogel (polyacrylamide) and the adherent cells removed by mechanical agitation. Seven lethally irradiated dogs were transplanted with 5.9 to 33.4 X 10(6) recovered adherent cells per kilogram of which 69.0% to 88.0% were Ia-positive. All dogs had hematologic recovery; six are alive and well with durable engraftment and one died on day 15 posttransplant. They are immunologically normal as determined by lymph node and bone marrow biopsies, lymphocyte function, and immunophenotyping of peripheral blood and bone marrow cells. These data provide further evidence that canine hematopoietic stem cells express Ia-like antigens and that these cells are capable of complete hematopoietic and immunologic reconstitution in an autologous model. 相似文献
28.
Fittkau M Voigt W Holzhausen HJ Schmoll HJ 《Journal of cancer research and clinical oncology》2004,130(7):388-394
Purpose To evaluate the ability of D-saccharic acid 1.4-lactone (SAL), a -glucuronidase inhibitor, to prevent irinotecan hydrochloride (CPT-11) from inducing mucosal damage as a cause of diarrhea in rats.Methods Wistar rats were divided into six groups of three animals each, administered 1.0 ml isotonic solution intraperitoneally once daily for up to three consecutive days, respectively for up to six days. The series were as follows: (1) On days 1–3: saline; (2). On days 1–3: 200 mg CPT-11/m2; (3) On days –3 to –1 relative to the first administration of CPT-11: 10 mg/ml SAL; on days 1–3: 200 mg CPT-11/m2; (4) On days –3 to +3 relative to the first administration of CPT-11: 10 mg/ml SAL, and on days 1–3: additional 200 mg CPT-11/m2; (5) On days 1–3: 200 mg CPT-11/m2 (0.5 ml) + 10 mg/0.5 ml SAL; (6) On days –3 to –1 relative to the first administration of CPT-11: 3 mg/ml SAL, and on days 1–3: 200 mg CPT-11/m2. Luminal mucosa damage of the small intestine was detected by histology 24 h after the last intraperitoneal application. Peptidase activities of the proximal jejunum were measured by using an in situ perfusion model.Results Following intraperitoneal CPT-11 treatment, using conventional histology of paraffin sections, we observed severe mucosal damage. This was reflected by a decrease of the villi/crypt ratio, an increase of apoptotic cells, as well as an increase of mitotic figures in the crypt region. There was a concomitant increased lymphatic infiltration in mucosa of CPT-11 treated rats. This damage pattern could be clearly reduced by co-treatment with the -glucuronidase inhibitor, SAL, independent of the treatment schedule. In contrast to our expectations based on previous reports, the intraperitoneal application of CPT-11 alone or in combination with SAL did not cause significant differences in luminal enzyme liberation in comparison with controls in the in situ perfusion assay.Conclusions The -glucuronidase inhibitor SAL is able to significantly reduce CPT-11-induced mucosal damage in the small intestine of rats. This observation might soon have a clinical impact for the treatment of patients with CPT-11. 相似文献
29.
Deeg HJ; Storb R; Thomas ED; Flournoy N; Kennedy MS; Banaji M; Appelbaum FR; Bensinger WI; Buckner CD; Clift RA 《Blood》1985,65(6):1325-1334
Seventy-five patients, 13 to 49 years of age, with acute nonlymphoblastic leukemia in first remission were treated with cyclophosphamide, fractionated total body irradiation, and marrow transplantation from an HLA-identical sibling and randomized to receive either cyclosporine (CSP) (n = 36) or methotrexate (MTX) (n = 39) as prophylaxis for graft-v-host disease (GVHD). All patients engrafted, and 22 who were given CSP and 21 who were given MTX, are alive at 20 to 47 (median, 35) months (P = .5). Engraftment as assessed by granulocyte recovery (P less than .0005) and platelet transfusion requirement (P = .01) was faster in patients on CSP. Twelve patients (33%) on CSP and 22 (56%) on MTX developed acute GVHD of grades II through IV (P = .07) and 15 of 30 on CSP and 14 of 32 on MTX that were at risk developed chronic GVHD. The most frequent causes of death were interstitial pneumonitis and marrow relapse of leukemia, which occurred with similar frequency in both groups. Beneficial effects observed in patients on CSP included less severe mucositis and shorter duration of hospitalization; adverse effects included renal function impairment and hypertension. These data confirm that CSP is a useful immunosuppressant in patients undergoing marrow transplantation but fail to show a significant improvement in survival as compared with the standard regimen of MTX. 相似文献
30.
Marrow transplantation with or without donor buffy coat cells for 65 transfused aplastic anemia patients 总被引:4,自引:3,他引:4
Storb R; Doney KC; Thomas ED; Appelbaum F; Buckner CD; Clift RA; Deeg HJ; Goodell BW; Hackman R; Hansen JA; Sanders J; Sullivan K; Weiden PL; Witherspoon RP 《Blood》1982,59(2):236-246
Sixty-five multiply transfused patients with severe aplastic anemia were given cyclophosphamide followed by grafts anemia were given cyclophosphamide followed by grafts from HLA-identical siblings. The effect of the administration of viable donor buffy coat cells following the marrow inoculum was evaluated with regard to graft rejection and survival. Results in 43 patients so treated are presented along with those in 22 concurrent patients given marrow alone. Most patients given buffy coat had positive in vitro tests of sensitization indicating a high risk for graft rejection, while all but one of the patients given marrow alone had negative tests. Thirty of the 43 (70%) patients given marrow and buffy coat are alive between 10 and 61 mo (median 36) after grafting; 4 died after graft rejection and 6 with acute or chronic graft-versus-host disease (GVHD). Eleven of the 22 (50%) patients given marrow alone are alive between 29 and 65 mo (median 52); 7 died after graft rejection and 3 with GVHD. The addition of buffy coat cell infusions to the marrow inoculum reduced the risk of rejection and increased survival in the currently reported transfused patients when compared to patients grafted before 1976. However, there was an increased risk of chronic GVHD. Recipients of marrow from female donors survived slightly better (73%) than recipients of male marrow (58%). 相似文献