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Journal of Interventional Cardiac Electrophysiology - Advanced non-fluoroscopic mapping systems for radiofrequency ablation (RFA) have shown to be an effective treatment of atrial fibrillation....  相似文献   
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Purpose  This study was designed to assess the long-term results of stapled hemorrhoidopexy in 291 patients with Grade III and Grade IV hemorrhoids after a minimum follow-up of five years. Methods  Records of patients submitted to stapled hemorrhoidopexy for Grade III and Grade IV hemorrhoids between January 1999 and December 2002 were retrospectively analyzed. Long-term outcome was evaluated with a standardized questionnaire and an office visit, including anorectal examination and rigid proctoscopy. Results  A total of 291 patients with Grade III (57.4 percent) and Grade IV (42.6 percent) hemorrhoids were evaluated. Intraoperative (20.3 percent) and postoperative (4.8 percent) bleeding was the most frequent complication. The questionnaire was submitted to all patients at a median follow-up of 73 (range 60–93) months. There were no symptoms related to hemorrhoids in 65.3 percent of patients, moderate symptoms in 25.4 percent of patients, and severe symptoms in 9.3 percent of patients. Fifty-three (18.2 percent) patients had recurrence. Reoperation was necessary in 21 (7.2 percent) patients (4 in Grade III hemorrhoids and 17 in Grade IV hemorrhoids; P < 0.001), with no recurrent symptoms and/or prolapse. Patient satisfaction for operation was 89.7 percent. Conclusions  Stapled hemorrhoidopexy is a safe and effective treatment for Grade III and Grade IV hemorrhoids. Recurrence requiring reoperation was higher in Grade IV hemorrhoids than in Grade III hemorrhoids. Reprints are not available.  相似文献   
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Background: Ultrasound (US) examination of gallbladder is considered to be reliable, both in morphological and functional evaluation. We used US to study the gallbladder of a series of centenarians in order to show the characteristics of this organ in these subjects. We then compared the data obtained with two control populations omposed of elderly and adult subjects, respectively. Methods: US examination was done after an overnight fast and after emptying the gallbladder at 15-min intervals for a period of 90 min. To induce emptying of the gallbladder, we chose a semisolid meal with a small caloric value (370 kcal). The following parameters were evaluated: fasting gallbladder volume (in milliliters) before administration of the meal (considered to be 100%); gallbladder emptying (according to the formula: fasting gallbladder volume minus post-meal gallbladder volume at 10-min intervals divided by fasting gallbladder volume: the result of this operation was multiplied by 100); gallbladder motor functions, such as ejection volume (ml), is considered as the difference between fasting gallbladder volume and residual volume; ejection fraction (%), considered as the difference between fasting gallbladder volume and residual volume, is expressed as percentage fasting volume; and ejection rate (%/min) is calculated by dividing ejection fraction by time requested to reach the residual volume. Results: We found a common bile duct diameter that was significantly higher in centenarians than in the elderly and adults. Gallbladder wall thickness was significantly higher in centenarians than in adults. We also found substantially significant differences between centenarians with and without gallstones and elderly and adult subjects in the following parameters: mean gallbladder volume (reduced), residual volume (reduced), ejection volume (reduced) and ejection rate (reduced). The differences were not significant for the ejection fraction, and they were slightly reduced in centenarians compared to the other groups. There was a negative correlation between age and axial length (transverse diameter), age and width and age and common bile duct (CBD) diameter in the elderly group only. Conclusions: The study of gallbladder function in elderly people and centenarians is important because this parameter is related to the quality of digestion and absorption of many alimentary substances as well as to the formation of cholesterol gallstones. We found that gallbladder functions in centenarians are almost normal with respect to the elderly and adults. Contractility was higher than in our elderly sample. This fact ensures a correct concentration of bile salts and a good intestinal transit rate. It may represent one of the factors allowing for good digestive function in these subjects, which contributes to their health status.  相似文献   
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In diabetic patients, the pathophysiologic mechanisms of exercise-induced left ventricular (LV) dysfunction remain controversial. In this study, the role of myocardial contractility recruitment in determining an abnormal LV response to isometric or dynamic exercise has been investigated in 14 diabetic patients with autonomic dysfunction. Ischemic heat disease was excluded by the absence of LV wall motion abnormalities induced by isotonic and isometric exercise and by coronary angiography. Left ventricular and myocardial function were studied at rest, and during isometric and isotonic exercise, by two-dimensional echocardiography; moreover, recruitment of an inotropic reserve was assessed by postextra-systolic potentiation at rest and at peak handgrip. An abnormal response of LV ejection fraction to isometric (9/14) or to dynamic (8/14) exercise was frequent in study patients. In these patients, baseline myocardial contractility was normal, and the significant increase in ejection fraction by postextrasystolic potentiation indicated a normal contractile reserve (65 ± 7% vs. 74 ± 6%, p=0.001). Nevertheless, the downward displacement of LV ejection fraction-systolic wall stress relationships during exercise suggests an inadequate increase in myocardial contractility. However, the abnormal ejection fraction at peak handgrip was completely reversed by postextrasystolic potentiation (67 ± 6% vs. 58.1 ± 10%, p=0.008), a potent inotropic stimulation independent of the integrity of adrenergic cardiac receptors. A defective inotropic recruitment, despite the presence of a normal LV contractile reserve, plays an important role in deexercise LV dysfunction in diabetic patients with autonomic neuropathy.  相似文献   
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HIV-1 protease inhibitors (PIs) may improve hematopoietic functions owing to their direct effects on bone marrow (BM) progenitor cells. In this study we investigated this hypothesis evaluating the effect of adding ritonavir (RTV) and indinavir (IND) on hematopoietic colony formation assays by colony-forming cell (CFC) and long-term culture-initiating cell (LTC-IC) assays, on apoptosis, on cytokine production and stromal cells, in subjects with HIV-1 infection, and in seronegative controls. After PI addition, CFC and LTC-IC assays in HIV-1-infected patients showed levels of colony growth significantly higher than those observed at baseline; the same PI activity on colony formation was observed in healthy subjects. No significant modifications on Fas, the membrane form of Fas (mFas) and Fas-ligand (FasL) expression, and on cytokine production were observed at BM level after the addition of PIs. At baseline, in HIV-1-infected patients, the majority of the stromal cells appeared as large and rounded, whereas after the addition of RTV or IND the stromal cells exhibited a "fibroblast-like" morphology and produced higher stem cell factor (SCF) and lower MIP-1alpha levels when compared with the stromal production without the addition of IND. RTV and IND increased colony growth of BM obtained either from HIV-1-infected patients or from normal individuals, in parallel with the normalization of functional and morphological characteristics of stromal cells.  相似文献   
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Experiments were undertaken to assess the role of amifostine in the activation of latent TGFbeta1 and in the smad proteins cascade (smad 2/3, smad4, smad7), focusing on megakaryocytes, in the bone marrow irradiated in vivo. Non-irradiated megakaryocytes were negative for active TGFbeta1. Immunopositivity to active TGFbeta1 was detected in megakaryocytes 10 days after irradiation in amifostine- treated and untreated marrows. Smad 2/3 and smad 4 were strongly positive in the nucleus of megakaryocytes 10 days after irradiation. At the same time, a predominant hypocellular bone marrow with foci of hematopoiesis was observed with few megakaryocytes. An increase in the number of reticulin fibers was also seen. In amifostine-treated marrows, smad 2/3 and smad4 were not detected in the nucleus but were positive in the cytoplasm of megakaryocytes 10 days after irradiation. Coincidentally, bone marrows were cellular with megakaryocytes. Smad7 immunoexpression was detected in the cytoplasm of megakaryocytes in the non-irradiated, amifostine-treated and in the irradiated, amifostine-treated marrows. Data indicate that amifostine does not prevent latent TGFbeta1 activation in irradiated megakaryocytes. While TGFbeta1 signal transduction occurs in megakaryocytes in untreated bone marrows, it is inhibited in megakaryocytes in amifostine-treated marrows due to the induction of smad 7 activation. This is the first report showing smad 7 activation by amifostine. Our results also suggest a role for TGFbeta1 as an inhibitor of megakaryocytes in vivo.  相似文献   
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