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排序方式: 共有906条查询结果,搜索用时 15 毫秒
1.
Uptake of iodine-123 MIBG by pheochromocytomas, paragangliomas, and neuroblastomas: a histopathological comparison 总被引:2,自引:0,他引:2
J Bomanji D A Levison W D Flatman T Horne P M Bouloux G Ross K E Britton G M Besser 《Journal of nuclear medicine》1987,28(6):973-978
The percentage uptake of [123I]metaiodobenzylguanidine (MIBG) by tumors of the paraganglion system is compared with the number of neurosecretory granules (assessed by both light and electron microscopy) in the subsequently resected tumors in six patients. Iodine-123 MIBG was injected intravenously; the tumor uptake of [123I]MIBG varied between 0.001% and 0.14% of the injected dose per gram of tumor tissue at 22 hr. The number of neurosecretory granules in tissue sections was scored on a scale of I-III. A direct proportional correlation was found between the percentage uptake of [123I]MIBG by the tumor and the number of neurosecretory granules in the tissue sections but not with plasma or urinary catecholamines. This technique for imaging reflects the storage status of the tumor better than plasma and urinary catecholamine measurements. 相似文献
2.
M A Levison D D Thomas R G Wiencek R F Wilson 《The Journal of trauma》1990,30(3):247-51; discussion 251-3
The records of 239 patients surviving more than 24 hours with full-thickness intraperitoneal colonic injuries over a 7-year period were reviewed. During the first 3 years, 29% (31/106) of the patients were managed by primary repair without colostomy. In the next 4 years, almost twice as many patients, 56% (75/133), with similar colonic trauma were treated without fecal diversion (p less than 0.05). Although there was no difference in the mean Trauma Score in the patients with primary repair in the two time periods, the Injury Severity Score (mean +/- sd) in the patients without colostomy in the later periods was significantly higher (17.8 +/- 2.1 vs. 20.2 +/- 5.1) (p less than 0.001). No patient suffered because of the increased incidence of primary repairs. These patients had five abdominal abscesses and only one leak, whereas the patients with colostomy had 15 intraperitoneal abscesses. Because of the safety when primary repair is performed, more liberal use of primary colonic repair following penetrating trauma is warranted. 相似文献
3.
Sorin Blendea Kort Eckman Branislav Jaramaz Timothy J Levison Anthony M Digioia 《Computer aided surgery》2005,10(1):37-43
This study presents a clinical validation of postoperative measurements of acetabular cup alignment following total hip arthroplasty (THA). The methodology was based on concurrent anatomic three-dimensional (3D) measurements of both the acetabular cup alignment and pelvic orientation, using an original CT/X-ray matching algorithm named Xalign. The subjects were 19 patients who had undergone bilateral THA using CT-based surgical navigation. All patients had postoperative pelvic CT scans and multiple antero-posterior (AP) pelvic X-rays. Using a proprietary software algorithm, the X-rays included in the study were matched with the corresponding postoperative CT scans. The goal of this method was to allow 3D anatomic pelvic and acetabular measurements on two-dimensional AP X-rays. The postoperative cup abduction, version and pelvic flexion angles were determined in three different ways: using CT images directly, applying the Xalign method, and finally by performing conventional (abduction only) measurements on AP pelvic X-rays. The cup orientation measured on CT images was taken as the ground truth. The Xalign measurement errors were defined as the difference between the CT cup values and those obtained by applying the matching method. The mean cup abduction error was 0.85 degrees +/- 1.3 degrees (+/- standard deviation) and the mean version error was 0.01 degrees +/- 1.99 degrees . Conventionally measured cup abduction ranged from 44 degrees to 62 degrees and correlated significantly (p = 0.001, r = -0.5) with pelvic flexion angle, proving the linear negative correlation between pelvic flexion and the error in conventional radiographic cup measurements. The Xalign method offered reasonable accuracy for cup orientation, and allowed cup and pelvic 3D anatomic measurements at different times. 相似文献
4.
Anulus fibrosus in bulging intervertebral disks 总被引:1,自引:0,他引:1
In this investigation the association of radial tears of the anulus fibrosus and bulging of the intervertebral disk was studied. An index of disk bulging was measured in sagittal anatomic sections in 149 lumbar disks from 31 cadavers. The indexes of disk bulging were correlated with stages of disk development and the presence of an annular tear. The largest disk-bulging indexes were always associated with radial tears of the anulus. Eighty-four percent of the disks with radial tears had disk-bulging indexes greater than 2.5 mm. Most normal adult disks had an index of less than 2.5 mm. The results challenge the concept that the anulus fibrosus is intact in bulging disks, although ruptured in herniated disks. 相似文献
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Emphysema of early onset associated with a complete deficiency of alpha-1-antitrypsin (null homozygotes) 总被引:6,自引:0,他引:6
We have compared lung function in 3 subjects with no alpha 1-antitrypsin (alpha 1-protease inhibitor) (null homozygotes) with subjects having the typical deficiency, PIZZ. We identified a 31-yr-old woman, presenting with severe obstructive lung disease, who had no detectable plasma alpha 1-antitrypsin, indicating homozygosity for a "null" (or PI*QO) allele of alpha 1-antitrypsin. Two of her sisters have a similar deficiency, one with an onset of symptoms at 17 yr of age. Because of the likelihood that there are a number of different PI*QO alleles, the type in this family has been named null Mattawa (QOmattawa). All 3 homozygotes have shown a marked deterioration of lung function over a 7-yr period of follow-up. In contrast, lung function tests of 6 age-matched nonsmoking subjects with alpha 1-antitrypsin deficiency, PI type ZZ, showed no abnormalities of lung function. The 15 to 20% of the normal plasma concentration of alpha 1-antitrypsin associated with the PI*Z allele appears to provide some protection to the lung in comparison with a complete deficiency state. 相似文献
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10.
Frequent administration by inhalation of salbutamol and ipratropium bromide in the initial management of severe acute asthma in children 总被引:1,自引:0,他引:1
J Reisman M Galdes-Sebalt F Kazim G Canny H Levison 《The Journal of allergy and clinical immunology》1988,81(1):16-20
A study was performed to compare the efficacy and safety of two therapeutic regimens for the treatment of children presenting to the emergency department with acute asthma. A regimen of inhaled salbutamol alone was compared to inhaled salbutamol combined with ipratropium bromide. Twenty-five children ranging in age from 5 to 15 years were enrolled in the study. Children with FEV1 less than or equal to 55% predicted were eligible to participate in the study. Subjects were randomized in a double-blind fashion into one of two treatment groups. Both groups received an initial dose of salbutamol by nebulizer of 150 micrograms/kg (0.03 cc/kg), followed by six consecutive doses of 50 micrograms/kg (0.01 cc/kg) at 20-minute intervals. In one group of subjects, 250 micrograms (1.0 ml) of ipratropium bromide respirator solution was added to the salbutamol administered at the time of the initial inhalation, and at 40 and 80 minutes, whereas the remaining subjects received a placebo with salbutamol at those times. Formal one-way statistical ANOVA with change in percent predicted FEV1 as a response variable confirmed there was a statistically significant difference at all time points caused by drug regimen during the 150-minute observation period. There was no significant difference in side effects reported in the two groups. Significant additional bronchodilation achieved with salbutamol and ipratropium bromide together indicates that there is likely a substantial cholinergic element to the bronchospasm observed in acute exacerbations of asthma in the pediatric age group. 相似文献