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排序方式: 共有439条查询结果,搜索用时 15 毫秒
121.
Comparison of pulmonary and pleural responses of rats and hamsters to inhaled refractory ceramic fibers 总被引:1,自引:1,他引:0
Gelzleichter TR; Bermudez E; Mangum JB; Wong BA; Janszen DB; Moss OR; Everitt JI 《Toxicological sciences》1999,49(1):93-101
The present study was designed to determine whether pleural fiber burdens
or subchronic pleural fibroproliferative and inflammatory changes can help
explain the marked interspecies differences in pleural fibrosis and
mesothelioma that are observed following long-term inhalation of RCF-1
ceramic fibers by rats and hamsters. Fischer 344 rats and Syrian golden
hamsters were exposed to RCF-1 for 4 h per day, 5 days per week, for 12
consecutive weeks. Lung and pleural fiber burdens were characterized during
and after exposure. For all time points, approximately 67% of fibers
associated with lung tissues from both rats and hamsters were longer than 5
microns in length. In comparison, fibers longer than 5 microns recovered
from the pleural compartment, following a 12-week exposure and 12 weeks of
recovery, accounted for 13% (hamsters) and 4% (rats) of the distribution.
In the 12 weeks after the cessation of exposure, the number of fibers
longer than 5 microns in length remained constant in the hamster at
approximately 150 fibers per cm2 pleura. This was 2 to 3 times the
corresponding fiber surface density in the rat. Significant pulmonary and
pleural inflammation was detected at all time points and for both species.
DNA synthesis by pleural mesothelial cells was quantified by
bromodeoxyuridine uptake following 3 days of labeling. Labeling indices
were higher in hamsters than in rats, both for RCF-1-exposed and filtered
air-control animals and was highest for the parietal surface of the pleura.
Significantly greater collagen deposition was measured in the visceral
pleura of hamsters 12 weeks post-exposure but was not significantly
elevated in rats. These findings demonstrate that subchronic inhalation
exposure to RCF-1 induces pleural inflammation, mesothelial-cell turnover,
pleural fibrosis, and an accumulation of fibers with a length greater than
5 microns in the hamster. The accumulation of long fibers in the pleural
space may contribute to the pathology observed in the hamster following
chronic inhalation of RCF- 1, whereas the presence of short, thin fibers
may play a role in the acute-phase biological response seen in both
species.
相似文献
122.
Adult height in women with early-treated congenital adrenal hyperplasia (21-hydroxylase type): relation to body mass index in earlier childhood 总被引:1,自引:0,他引:1
To investigate if obesity, as judged by increased body mass index (BMI), during childhood is associated with impaired adult stature in patients with 21-hydroxylase-type congenital adrenal hyperplasia (CAH), a retrospective analysis was carried out on outpatient records of 30 girls with CAH who had reached adult height. Height SD score for age (HtSDS(ca)), HtSDS for bone age (HtSDS(ba)), BMI and steroid dosage in early childhood (3.2-4.6 years) and later childhood (7.2-9.1 years), were compared with adult HtSDS (HtSDS(adlt)), adult HtSDS less mid-parental HtSDS (HtSDS(adlt) - HtSDS(mp)), predicted adult height SDS (HtSDS(pdct)), adult height SDS less predicted adult HtSDS (HtSDS(adlt) - HtSDS(pdct)) and age at menarche. Mean (SD) for HtSDS(adlt) was -1.13 (1.05), mean HtSDS(pdct) -0.12 (0.9) and mean age at menarche 13.5 (1.9) years. BMI in childhood was not correlated with HtSDS(adlt) but showed negative correlations with HtSDS(adlt) - HtSDS(mp) (r = -0.43; p < 0.02) and HtSDS(adlt) - HtSDS(pdct) (r - 0.45; p < 0.02). BMI in later childhood showed negative correlations with HtSDS(adlt) - HtSDS(pdct) (r = -0.61; p < 0.001) and age at menarche (r = -0.63; p < 0.001). We conclude that in girls with early-treated CAH, a high BMI during early childhood is associated with loss of genetic height potential, and in later childhood with over-prediction of adult height and early menarche. Adult stature, body mass index, congenital adrenal hyperplasia (21-hydroxylase type), predicted adult height
DB Grant, Medical Unit, Institute of Child Health, Guilford Street, London WC1N 1EH, UK 相似文献
DB Grant, Medical Unit, Institute of Child Health, Guilford Street, London WC1N 1EH, UK 相似文献
123.
124.
Thornton MH; Johns DB; Campeau JD; Hoehler F; DiZerega GS 《Human reproduction (Oxford, England)》1998,13(6):1480-1485
The objective of this study was to assess the safety and to make a
preliminary assessment of the efficacy of 0.5% ferric hyaluronate adhesion
prevention gel in reducing adhesions in patients undergoing peritoneal
cavity surgery by laparotomy, with a planned 'second-look' laparoscopy. The
study was a randomized, open-label, placebo- controlled, parallel-group
design in patients desirous of fertility at the Women's and Children's
Hospital, Department of Obstetrics and Gynecology, University of Southern
California School of Medicine, Los Angeles, California. Female patients
aged 24 to 41 years received 300 ml 0.5% ferric hyaluronate adhesion
prevention gel or lactated Ringer's solution as an intraperitoneal
instillate at the completion of the laparotomy procedure. At second-look
laparoscopy 4-12 weeks after the laparotomy, the presence of adhesions was
evaluated. Haematology and serum chemistry were determined throughout the
study interval. All patients tolerated the procedures well and did not
manifest any serious adverse events. At second-look laparoscopy, patients
treated with 0.5% ferric hyaluronate adhesion prevention gel had
significantly fewer adhesions than control patients. When adhesions did
form, they were significantly less extensive and less severe in patients
who received 0.5% ferric hyaluronate adhesion prevention gel. In
conclusion, 0.5% ferric hyaluronate adhesion prevention gel was safe and
highly efficacious in the reduction of the number, severity and extent of
adhesions throughout the entire abdomen following peritoneal cavity
surgery.
相似文献
125.
Layman LC; Edwards JL; Osborne WE; Peak DB; Gallup DG; Tho SP; Reindollar RH; Roach DJ; McDonough PG; Lanclos KD 《Molecular human reproduction》1997,3(4):315-320
Women with recurrent abortion, primary unexplained infertility, and
gestational trophoblastic neoplasia (GTN) manifest disordered human
chorionic gonadotrophin (HCG) secretion. Mutations in the HCG
beta/luteinizing hormone (LH) beta gene complex could cause aberrant HCG
production in these disorders. The purpose of this study was to determine
whether HCG beta gene deletions occur in women with recurrent abortion or
primary unexplained infertility, and whether HCG beta gene duplications are
present in women with GTN. DNA was extracted from 10 patients with
unexplained recurrent abortion, 10 patients with unexplained primary
infertility, 12 patients with GTN, three partners of women with GTN, and 30
controls. Southern blots were constructed and hybridized with DNA probes
for HCG beta-5 and the LH beta gene. No gene deletions were identified in
patients with recurrent abortion or primary unexplained infertility.
Likewise, no gene duplications were identified in women with GTN. A
previously described Mbol restriction fragment length polymorphism (RFLP)
was identified in both patients and controls. A new Pstl RFLP was also
characterized, but was present in patients and controls.
Deletion/duplication mutations in the HCG beta/LH beta gene complex do not
appear to be common causes of aberrant HCG production in humans with these
disorders.
相似文献
126.
Structure and sequence variation at the human leptin receptor gene in lean and obese Pima Indians 总被引:14,自引:0,他引:14
The cloning of human and mouse cDNAs from brain that encode high affinity
leptin receptors was recently reported. We have physically localized the
human leptin receptor gene (LEPR) to a region at 1p31, between the
anonymous microsatellite markers D1S515 and D1S198. The genomic structure
of the human leptin receptor gene, corresponding to the published human
brain cDNA sequence, spans over 70 kb and includes 20 exons. Since the
leptin receptor gene is a candidate gene for obesity, and because of its
proximity to D1S198, a marker previously linked to insulin secretion, the
LEPR gene was sequenced in 20 non- diabetic Pima Indians chosen for
extremes in percent body fat and in their acute insulin response to
intravenous glucose. Seven polymorphic sites were identified. Two of these
polymorphisms, Lys109Arg and Gln223Arg, are amino acid substitutions in the
extracellular domain of the leptin receptor, one polymorphism is a silent
substitution, and four occur in non-coding regions of the leptin receptor.
Four of these sites are in linkage disequilibrium with one another.
Nucleotides at three noncoding polymorphic sites were found exclusively in
obese Pima Indians. This demonstrates an association between variation at
the leptin receptor gene and obesity in humans.
相似文献
127.
128.
129.
130.
Ryan H. Moy Gustavo Dos Santos Fernandes Philip Jonsson Joanne F. Chou Azfar Basunia Geoffrey Y. Ku Sree B. Chalasani Michelle S. Boyar Zoe Goldberg Avni M. Desai Amelia Gabler Michael F. Berger Laura H. Tang Jaclyn F. Hechtman David P. Kelsen Mark Schattner David H. Ilson David B. Solit Barry S. Taylor Nikolaus Schultz Marinela Capanu Yelena Y. Janjigian 《The oncologist》2020,25(1):e68-e74