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21.
Bovine fetal lymphocytes were examined for their ability to respond to the mitogens phytohemagglutinin (PHA), Concanavalin A (ConA) and pokeweed mitogen (PWM) in the lymphocyte blastogenesis test (LBT). PHA-, Con A- and PWM-responsive lymphocytes appeared simultaneously at 75-80 days of gestation. The response increased with age of the fetus until, by 120 days of gestation, the response to PHA, Con A and PWM of many fetuses was in the range of values obtained with lymphocytes from normal adult cattle.  相似文献   
22.
It is still unclear whether i.v. immunoglobulins (Ig) can facilitate the reproductive prognosis of women who have suffered recurrent pregnancy loss. We report the results of a multicentre placebo- controlled study on the effect of Ig administration on pregnancy outcome in 46 women who had suffered at least three recurrent miscarriages. All were screened to exclude chromosomal or Mullerian abnormalities, the presence of antinuclear antibodies, lupus anticoagulant (LA) or elevated titres of anticardiolipin antibodies which may have revealed an underlying autoimmune problem. To avoid a selection bias towards ongoing pregnancies, i.v. Ig or placebo were administered between weeks 5 and 7 of gestation for 2 consecutive days as soon as each woman knew she was pregnant and before embryonic heart activity could be detected. A further infusion was administered at week 8 when ultrasonography confirmed an ongoing embryonic development. In all, 68% of the women who received Ig went to term versus 79% of those who received a placebo (not significant), with no significant differences in the pregnancy course or the perinatal outcome. These results suggest either that women with recurrent miscarriages who have no recognized cause of pregnancy loss have a good reproductive prognosis without any treatment or that the emotional care associated with the administration of a placebo can indirectly facilitate the progression of pregnancy.   相似文献   
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Mouse T lymphocytes sensitized to alloantigens were cloned by limiting dilution in the presence of interleukin 2. Clones were tested for surface markers Thy-1, Lyt-1 and Lyt-2, and for cytotoxic function. Production of interferon (IFN) by clones either (a) stimulated with allogeneic cells; (b) activated with concanavalin A (Con A); or (c) infected with Semliki Forest virus or Newcastle disease virus were assayed. All clones produced IFN upon Con A stimulation and most after virus infection. Analysis of the IFN produced by a single clone, using anti-IFN antisera, showed that while Con A stimulation induced production of type II IFN (IFN-gamma), the IFN produced after virus infection was type I IFN (IFN-alpha/beta).  相似文献   
26.
Recognizing that researchers and clinicians are increasingly faced with assessing, treating, and studying ethnically, racially, and culturally diverse populations, one question is whether the appropriate tools exist. This special section aspires to advance the available assessment strategies that are appropriate for the treatment, prevention, and research of diverse children and adolescents with anxiety symptoms and disorders. This introduction presents an overview of anxiety and its disorders among multiethnic youth and identifies emerging challenges and opportunities in the assessment and treatment of anxiety symptoms and disorders among Asian American and Pacific Islander, Hispanic/Latino, African American, and European American children and adolescents within a sociocultural context.  相似文献   
27.
The ileoanal J pouch: radiographic evaluation   总被引:1,自引:0,他引:1  
Hillard  AE; Mann  FA; Becker  JM; Nelson  JA 《Radiology》1985,155(3):591-594
Endorectal ileoanal pull-through offers an attractive alternative to proctocolectomy and ileostomy for patients with ulcerative colitis, Gardner syndrome, and familial polyposis. To our knowledge, a careful radiographic analysis of the ileum, ileal pouch, and ileoanal anastomosis after ileoanal pull-through has not been reported. Thirty-two patients with ulcerative colitis, Gardner syndrome, and familial polyposis underwent colectomy, mucosal proctectomy, and endorectal ileoanal pull-through of a 15-cm ileal "J" pouch and loop ileostomy. Twenty-five (78%) of 32 of all the pouches radiographically demonstrated spiral folds extending from the middle of the pouch to the pectinate line. Other radiographic features included a mesenteric mass effect, pseudopolyps, and a central lucency that indicated intrapouch sutures. Radiographs provide useful information in the postoperative management of the ileal pull-through.  相似文献   
28.
From 1962 to 1983, 117 patients between the ages of 16 and 72 years (mean, 25 years) underwent total correction of tetralogy of Fallot. All patients were operated on because of recent deterioration. Eighty (68%) had had previous surgical palliation. Complications occurred in 38 cases (32%) before total correction and were more frequent in older patients. The hospital mortality was 7.8% and was highest in older patients and those with a previous Potts shunt. Fifty-nine patients were followed up for as long as 23 years (mean, 9.2 years) after total correction. The probability of survival at 5, 10, and 15 years after total correction was 96%, 96%, and 84%, respectively. The actuarial freedom from any significant cardiovascular event at 5, 10, and 15 years was 84%, 73%, and 50%, respectively. Reoperation was required in ten cases (17%), in which there was one operative death. Late death occurred in four cases (6.8%). Left ventricular dysfunction was documented in ten patients (17%), three of whom had mural thrombi and two of whom had cerebrovascular accidents. A significant rhythm disorder was present in 13 patients. Fifty-four of the 55 surviving patients were in New York Heart Association (NYHA) functional class I or II at last follow-up. We conclude that 1) total correction of tetralogy of Fallot in adults is associated with a low operative mortality, similar to that in children, and offers symptomatic relief in most cases; 2) the long-term survival is excellent, but late sequelae become more frequent at late follow-up; 3) "corrective" reoperation can be done with a low risk; and 4) most of the survivors are in NYHA functional class I or II and lead normal, productive lives.  相似文献   
29.
A new technique is described for relief of diffuse obstruction in the left ventricular outflow tract without aortic valve replacement. Left ventricular septoplasty was performed, preserving the aortic valve. The supra-valve stenosis was repaired using a Y-shaped extension of the aortotomy proximally and a pantaloon-shaped patch of woven Dacron fabric. A 10-year-old girl with "tunnel" or diffuse stenosis obtained striking relief of left ventricular hypertension by this technique.  相似文献   
30.
This study evaluated the ability of five interim endodontic restorative materials to resist microleakage. Sixty extracted human molars were prepared for initial endodontic therapy via occlusal access preparations. After removal of the pulpal tissue, a cotton pellet was placed in the pulp chamber. The access preparations were sealed with one of the following materials or combinations: TERM, Cavit, IRM, Ketac-Silver, or a IRM-Cavit "sandwich" restoration. The specimens were thermocycled for 24 hours (800 cycles), immersed in methylene blue dye for 4 hours, sectioned, and evaluated under a microscope for microleakage. TERM, Cavit, and the IRM-Cavit "sandwich" had virtually no microleakage, while Ketac-Silver and IRM exhibited gross microleakage.  相似文献   
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