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31.
PURPOSE: The aim of this study was to determine the optimal dose and dosing interval of nitroglycerin ointment to heal chronic anal fissures. METHOD: A randomized, double-blind study of intra-anally applied nitroglycerin ointment (Anogesic) was conducted in 17 centers in 304 patients with chronic anal fissures. The patients were randomly assigned to one of eight treatment regimens (0.0, 0.1, 0.2, 0.4 percent nitroglycerin ointment applied twice or three times per day), for up to eight weeks. A dose-measuring device standardized the delivery of 374 mg ointment. Healing of fissures (complete reepithelialization) was assessed by physical examination using an observer unaware of treatment allocation. The subjects assessed pain intensity daily by completing a diary containing a visual analog scale for average pain intensity for the day, the worst pain intensity for the day, and pain intensity at the last defecation. RESULTS: There were no significant differences in fissure healing among any of the treatment groups; all groups, including placebo had a healing rate of approximately 50 percent. This rate of placebo response was inexplicably higher than previously reported in the literature. Treatment with 0.4 percent (1.5 mg) nitroglycerin ointment was associated with a significant (P < 0.0002) decrease in average pain intensity compared with vehicle as assessed by patients with a visual analog scale. The decreases were observed by Day 4 of treatment. At 8 weeks the magnitude of the difference between 0.4 percent nitroglycerin and control was a 21 percent reduction in average pain. Treatment was well tolerated, with only 3.29 percent of patients discontinuing treatment because of headache. Headaches were the primary adverse event and were dose related. CONCLUSION: Nitroglycerin ointment did not alter healing but significantly and rapidly reduced the pain associated with chronic anal fissures.  相似文献   
32.
To determine whether clinical parameters alone can differentiate normal versus decreased systolic left ventricular function in patients with heart failure.Detailed clinical data were collected prospectively from 225 consecutive patients who were hospitalized with heart failure. Findings in patients with normal (ejection fraction > or =45%) or decreased (ejection fraction <45%) left ventricular function were compared.Systolic function was normal in 104 patients (46%) and decreased in 121 patients (54%). Patients with normal function were older (mean [+/- SD] age, 59 +/- 13 years vs. 54 +/- 13 years, P = 0.007) and more likely to be female (56% vs. 35%, P = 0.001), obese (body mass index > or =30 kg/m(2), 62% vs. 48%, P = 0.04), have marked systolic (> or =160 mm Hg, 50% vs. 27%, P <0.001) and diastolic (> or =110 mm Hg, 25% vs. 13%, P = 0.02) hypertension, and use calcium antagonists (34% vs. 14%, P = 0.001). Patients with decreased function were more likely to use alcohol (37% vs. 20%, P = 0.007), angiotensin-converting enzyme (ACE) inhibitors (85% vs. 62%, P <0.001), and digoxin (57% vs. 27%, P <0.001); and more likely to have tachycardia (51% vs. 32%, P = 0.004), rales (89% vs. 80%, P = 0.05), electrocardiographic left ventricular hypertrophy (42% vs. 22%, P = 0.002), left atrial abnormality (52% vs. 22%, P <0.001), or flow cephalization on chest radiograph (91% vs. 79%, P = 0.02). Only sex, tachycardia, and use of digoxin and ACE inhibitors were associated with ventricular function in multivariable analysis. However, the sensitivity, specificity, and predictive values for all clinical variables were low. Differences in clinical parameters in heart failure patients with decreased versus normal systolic function cannot predict systolic function in these patients, supporting recommendations that heart failure patients should undergo specialized testing to measure ventricular function.  相似文献   
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De novo malignancies after intestinal and multivisceral transplantation   总被引:3,自引:0,他引:3  
BACKGROUND: Maintenance immunosuppression required after organ transplantation creates a permissive environment in which cancer cells can proliferate because of lack of natural immunologic surveillance. With more than a decade of clinical experience, this report is the first to address the risk of de novo cancer after intestinal transplantation. METHODS: A total of 168 consecutive intestinal transplant recipients (86 children and 82 adults) were studied, of whom 52% were male and 91% were white. Surveillance, Epidemiology, and End Results data was used to count expected rates of de novo cancers in the general population matched for age, sex, and length of follow-up. RESULTS: With a mean follow-up of 47+/-41 months, 7 (4.2%) patients developed nonlymphoid de novo cancer, with a cumulative risk of 3% at 5 years and 28% at 10 years. Of these malignancies, one was donor-driven adenocarcinoma. With 0.58 being the expected rate of malignancy for the general population, the risk among intestinal recipients was 8.7 times higher (P =0.01). Such morbidity was significantly higher (50 times) among younger patients (<25 years), with a slight male preponderance. Induction immunosuppression was associated with early onset of de novo cancer. Patient survival after diagnosis of de novo cancer was 72% at 1 year, 57% at 2 years, and 29% at 5 years. CONCLUSION: With conventional immunosuppression, intestinal recipients are at a significantly higher risk of developing de novo cancer when compared with the general population. Thus, a novel tolerogenic immunosuppressive strategy has been recently implemented to reduce the lifelong need for immunosuppression.  相似文献   
35.
The Kheda project experience has shown that bio-environmentalcontrol of malaria is feasible, cost effective and ecologicallysound. It clearly brings out the need to consider health issuesat the planning stage of all developments. Bio-environmentalcontrol of malaria is suggested as the first line of attackfor the control of mosquitoes, malaria and other mosquito-bornediseases. Insecticides may be reserved for short-term use. Thiswill enable judicious and selective use of insecticides in solelyepidemic situations. The growing problem of resistance to insecticidesin mosquitoes as well as environmental pollution, can then besolved on a long term basis.  相似文献   
36.
研究背景和目的   在急诊救治的过程中最重要的就是快速建立静脉通道,以补充体液、给药以及输血等.但是,由于皮下结构(如血管深度、脂肪组织、皮肤色素、血管内血容量)的复杂性,往往阻碍了肉眼下静脉穿刺过程的实施.血管超声可以辅助寻找相对较粗的静脉,但是此设备和技术的要求较高,影响了其在临床的广泛应用;可见光透射法所得结果不甚可靠,且容易造成灼伤.红外成像时由于其穿透深度较可见光深,而且血液对红外光能量的吸收明显高于脂肪和黑色素等血管周围组织,因而可以得到对比度清晰的图像.……  相似文献   
37.
Abstract. The susceptibility of cultured rat kidney parenchymal components to natural killer (NK) cell and lymphokine-activated killer (LAK) cell-mediated lysis in a 4-h in vitro 51chromium assay was investigated. Large granular lymphocytes (LGL) in the spleen and in the kidney allograft were able to lyse YAC cells during rejection, but they did not damage target endothelial, glomerular mesangial, glomerular epithelial, or tubular cells in resting state. Stimulation of the target cells with gamma-interferon - known to induce MHC (class II) antigens on the target cell surface - did not make the target cells susceptible to NK-mediated lysis. LAK cells generated by a 3-day incubation with interleukin-2 (IL-2) effectively lysed both YAC and P815 target cell lines. LAK cells were also slightly cytotoxic to all tested parenchymal target components in resting state. Gamma-interferon treatment of the cultured parenchymal cells prior to the chromium release assay, however, reduced LAK-mediated parenchymal cell cytotoxicity to nearly nondetectable levels. Obviously, many lymphokines, including IL-2 and gamma-interferon, are produced during rejection at the site of inflammation. This might induce the generation of LAK cells in situ as the lymphokines induce the production of MHC antigens in the graft. We interpret these findings as indicating that regardless of the generation of LAK, the protective effect of gamma-interferon neutralizes the LAK effect, and we suggest that neither LGL nor LAK cells play any essential role in rat kidney allograft rejection.  相似文献   
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CD3delta-deficient (delta degrees) mice are defective in alphabeta T cell development. Here we explore the capacity of TCR-CD3 signaling complexes expressed on delta degrees thymocytes to mediate the following functional outcomes in response to antibody cross-linking: (i) the transition from the CD4-CD8- to CD4+CD8+ stage, (ii) the transition from the CD4+CD8+ to CD4+CD8- or CD4-CD8+ stages and (iii) the induction of apoptosis. We provide evidence that CD3deltaepsilon complexes are dispensable for mediating the anti-CD3-mediated CD4-CD8- to CD4+CD8+ transition. On the other hand, CD3delta is critical at the CD4+CD8+ stage. We demonstrate that CD4+CD8+ thymocytes from delta degrees mice, unlike delta degrees CD4-CD8- thymocytes and wild-type CD4+CD8+ thymocytes, require prolonged or consecutive stimuli to elicit functional responses. Depending on the nature of the secondary stimulus, delta degrees thymocytes can be induced to undergo apoptosis or preferential maturation to the CD4-CD8+ stage. Taken together these results indicate that the signaling capacity of the TCR-CD3 complex is noticeably altered in the absence of CD3delta. The essential role of CD3delta at the CD4+CD8+ stage of development correlates with the onset of TCRalpha rearrangement, consistent with a critical structural and/or functional relationship between CD3delta and TCRalpha.   相似文献   
40.
Chuang  VP; Wallace  S 《Radiology》1980,135(2):295
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