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61.
Experimental liver metastasis was studied in 4-5 week old athymic nude mice that were injected intrasplenically with a human colorectal tumor cell line (LoVo). A treatment schedule combining 5-fluorouracil and interferon (IFN) was previously shown to inhibit liver metastases. When this treatment was delayed until after splenectomy at 1, 2 and 3 weeks after tumor cell injections, liver metastases were not inhibited. However, when IFN was given during the interval between tumor cell injections and splenectomy (as neoadjuvant therapy), liver metastases were inhibited in the 2 and 3 week groups, but not in the 1 week group.  相似文献   
62.
We retrospectively evaluated 401 selected patients who had estrogen receptor (ER) assays both at primary surgery and at relapse in an accessible site to determine the clinical relevance of the subsequent ER determination. The median time between ER assessments was 27 months (range: 2-122 months). The median follow-up time from diagnosis was 6 years (range: 2-12 years). For patients with ER+ tumors at primary diagnosis, 29% (76/261) had ER- tumors at relapse, while for ER- primaries, the conversion rate was 33% (46/140). Conversions from ER+ to ER- occurred more often when the time interval between assays was less than one year (p = 0.004), while conversions from ER- to ER+ tended to occur late (beyond three years; p = 0.0003). Treatments received between assays (usually adjuvant therapy) had only a slight influence on ER status conversion. Post-relapse survival was poor for patients who had the biopsy accessible recurrence within one year; an expression of the aggressive nature of the disease. Among patients whose accessible relapse was beyond one year, those with ER- primaries who converted to ER+ had a longer survival than those whose recurrence was classified again as ER- (p = 0.006). This group of patients with ER- primaries who recurred beyond one year with an ER+ tumor in an accessible site represented 29% (40/140) of all patients with ER- primaries and had an estimated overall survival rate of more than 60% at 6 years from the accessible relapse. ER determination upon relapse within one year has very little clinical relevance.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
63.
Vertical banded gastroplasty is an accepted surgical treatment for morbid obesity. The aim of this study was to evaluate its effect on the natural history of gastritis, as the occurrence of gastritis and dysplasia have been reported after gastric bypass, another type of bariatric surgery. Thirty-four patients who underwent vertical banded gastroplasty between 1983 and 1987 were studied, and the follow-up varied from 1 to 47 months (mean 22 months). We found no increase of gastritis and intestinal metaplasia after surgery, and we did not observe any case of gastric dysplasia. Only one patient with pre- and postoperative specimens showed a deterioration in gastric histology after surgery, and this was of a minor degree. These initial results are encouraging for surgeons interested in the treatment of morbid obesity.  相似文献   
64.
BACKGROUND: Quality of life has increased in popularity as an outcome measure in health research. However, the measurement of quality of life has been questioned on methodologic grounds, as it often shows little association with objective measures of disease status. OBJECTIVE: For this report we studied the determinants of pediatric asthma caregiver report of quality of life and its relationship to disease burden. METHOD: Ninety-eight children who were admitted to a Pediatric Day Program for an asthma evaluation were enrolled in an outcome study. A complete set of medical records for the 2-year period before and after the admission was collected and systematically coded for health care utilization. Using the Pediatric Asthma Caregiver's Quality of Life Questionnaire, data were collected at baseline, discharge, and year after the admission. Caregiver negative affect (anxiety and depression), measured with the Brief Symptom Inventory, was also collected at baseline and discharge. RESULTS: Caregiver report of quality of life was unrelated to health care utilization at baseline but instead was significantly related to baseline caregiver negative affect. A significant relationship between health care utilization and quality of life was present at followup. The Emotional Function scale from the quality of life measure can account for most of the relationship between quality of life and negative affect. CONCLUSIONS: Caregiver affect may have a considerable influence on report of quality of life. Understanding the individual characteristics of the respondent is important when using a quality of life instrument as an outcome measure.  相似文献   
65.
We are interested in the mechanisms that generate the mature cerebral cortex. We used bromodeoxyuridine (BrdU) to label cortical cells as they were being born. We followed the fates of specific sets of cortical precursors in normal mice and in mice in which other groups of cortical progenitors had been destroyed with the antimitotic agent methylazoxymethanol acetate (MAM Ac). In normal mice, most cells destined for the cerebral cortex were produced from embryonic day 12 (E12) to E16 in the expected inside-to-outside sequence (deep layers first, superficial layers last). Injection of MAM Ac at E13 killed cells that would normally have contributed to the deep cortical layers. As a consequence, the cortex was thinned by ∼25% at postnatal day 21 (P21). However, all laminae were present and had normal connections with subcortical structures, although all were proportionately thinner. BrdU injected on E16 labelled a normally sized complement of cells that spanned a larger proportion of the depth of the thinned cortex. Thus, the deep cortical layers comprised many cells that were born several days later than normal. At embryonic ages prior to E12, a transient set of cells is produced in the early telencephalon. After injection with MAM Ac at E10, the cortex appeared histologically and histochemically normal at P21. However, many cells that would normally have contributed to superficial cortex (born on E15) were significantly deeper than normal. These results suggest that, during the early stages of cortical development, the nervous system is sufficiently plastic to compensate to some extent for the destruction of specific precursor cells by altering the fates of neurons born later. They indicate that the embryonic date on which a cortical cell is born does not necessarily determine its eventual phenotype.  相似文献   
66.
67.
We examined distribution characteristics of the body mass index (BMI; weight/height; kg/m2) in a sample of 1128 male and 1372 female Pima Indians aged 15-65 years. We found that women had a higher mean and variance of BMI than men. From commingling analyses, we determined that the distribution of BMI could be accounted for either by a single skewed distribution or by a mixture of multiple normal components. These component distributions may be used to define provisional thresholds in selecting families for genetic studies. To ensure genetic segregation of obesity predisposing genes in Pima families will require that some members have BMIs > or = 40 kg/m2.  相似文献   
68.
A Greenough  J Pool  J G Gleeson    J F Price 《Thorax》1988,43(11):937-938
In 19 asthmatic children, aged 2-6 years, the effect of six weeks' treatment with inhaled budesonide or placebo on functional residual capacity (FRC--helium dilution) and bronchodilator responsiveness was assessed in a double blind, randomised crossover trial. FRC was increased in most children at the start of treatment. Treatment with budesonide was associated with a reduction in FRC by comparison with placebo (median change 9% v 0%; p less than 0.05). There was a trend towards a greater response to a bronchodilator after budesonide. The results suggest that inhaled corticosteroids reduce hyperinflation in young asthmatic children.  相似文献   
69.
C T Price  D S Scott  F E Reed  M F Riddick 《Spine》1990,15(12):1294-1299
The authors report their preliminary experience with the Charleston bending brace for the treatment of adolescent idiopathic scoliosis. This brace holds the patient in the position of maximum side bend correction and is worn only at night. Patients in this prospective multicentered study met all the following criteria: skeletal immaturity (Risser 0, 1+, or 2+), curvature greater than 25 degrees before bracing, no prior treatment, and greater than 1-year follow-up since initiation of treatment. There were 191 structural curves in the 139 patients. One hundred fifteen patients (83%) showed improvement or less than 5 degree change in curvature. Twenty-four patients (17%) demonstrated an increase in curvature greater than 5 degrees. Based on these preliminary results, continued use of bending brace treatment at nighttime only is justified for adolescent idiopathic scoliosis. Patients with double curves should be observed closely for increase in compensatory curves.  相似文献   
70.
In this admittedly preliminary view of the future, the authors present a number of new concepts in MR imaging and consider their possible advantages and limitations.  相似文献   
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