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排序方式: 共有833条查询结果,搜索用时 15 毫秒
741.
Treatment of blunt hepatic injuries: role of CT 总被引:2,自引:0,他引:2
Foley WD; Cates JD; Kellman GM; Langdon T; Aprahamian C; Lawson TL; Middleton WD 《Radiology》1987,164(3):635-638
Serial dynamic upper abdominal computed tomography (CT) studies were performed on 20 patients as part of the conservative treatment of blunt hepatic injuries (hematoma, laceration, or fracture). Fourteen of these patients had either major or minor associated hemoperitoneum. In 13 patients, hemoperitoneum was either significantly reduced or absent by 1 week. A severe delayed hemorrhage occurred in one patient 7 1/2 days after admission; a large and unchanged volume of intraperitoneal fluid had been seen on a preceding abdominal CT scan. One other patient who had a satisfactory response underwent surgery for a pancreatic laceration. Serial abdominal CT studies are an integral part of the conservative treatment of blunt hepatic injuries and seem to be useful in monitoring resorption of hemoperitoneum and the pattern of healing of intrahepatic hematomas, lacerations, and fractures. 相似文献
742.
743.
744.
Prediction of obesity in children at 5 years: A cohort study 总被引:8,自引:0,他引:8
MJ O'CALLAGHAN GM WILLIAMS MJ ANDERSEN W BOR JM NAJMAN 《Journal of paediatrics and child health》1997,33(4):311-316
Objective: To examine determinants of moderate and severe obesity in children at 5 years of age.
Methodology: A prospective cohort of mothers were enrolled at first antenatal visit, and interviewed shortly after delivery, at 6 months and 5 years. Detailed health, psychological and social questionnaires were completed at each phase by mothers, and child health questionnaires at 6 months and 5 years. At 5 years 4062 children were assessed physically, the Peabody Picture Vocabulary Test administered and mothers completed a modified Child Behaviour Checklist. Moderate obesity was defined as BMI between 85th and 94th percentiles inclusively, and severe obesity as a BMI greater than the 94th percentile.
Results: Independent predictors of severe obesity at 5 years were birthweight, female gender, maternal BMI and paternal BMI. Moderate obesity at 5 years was predicted by birthweight, paternal BMI and sleeplessness at 6 months, while small for gestational age (SGA) status and feeding problems at 6 months were protective factors for moderate obesity. Obesity was not associated with problems of language comprehension or behaviour.
Conclusions: Findings of this study suggest that biological rather than psychosocial factors are the major determinants of obesity at 5 years. 相似文献
Methodology: A prospective cohort of mothers were enrolled at first antenatal visit, and interviewed shortly after delivery, at 6 months and 5 years. Detailed health, psychological and social questionnaires were completed at each phase by mothers, and child health questionnaires at 6 months and 5 years. At 5 years 4062 children were assessed physically, the Peabody Picture Vocabulary Test administered and mothers completed a modified Child Behaviour Checklist. Moderate obesity was defined as BMI between 85th and 94th percentiles inclusively, and severe obesity as a BMI greater than the 94th percentile.
Results: Independent predictors of severe obesity at 5 years were birthweight, female gender, maternal BMI and paternal BMI. Moderate obesity at 5 years was predicted by birthweight, paternal BMI and sleeplessness at 6 months, while small for gestational age (SGA) status and feeding problems at 6 months were protective factors for moderate obesity. Obesity was not associated with problems of language comprehension or behaviour.
Conclusions: Findings of this study suggest that biological rather than psychosocial factors are the major determinants of obesity at 5 years. 相似文献
745.
OBJECTIVE: Meconium aspiration syndrome remains a common cause of respiratory failure in neonates. The acute effects of meconium aspiration are inactivation of lung surfactant in vivo and in vitro. This study investigated the delayed effects of meconium on alveolar surfactant phospholipids and protein levels in spontaneously breathing animals. METHODS: Twenty-two adult rats were given 4.3 mg of dry weight human meconium after endotracheal intubation. Rats were briefly mechanically ventilated in room air, extubated, then killed after 16 (n = 6), 24 (n = 6), 48 (n = 6), and 72 hours (n = 4). Control animals received the same volume of normal saline (n = 7) or no meconium (n = 7). Bronchoalveolar lavage and tissue specimens were evaluated for inflammatory cells, total proteins, surfactant phospholipids, and surfactant proteins. RESULTS: Meconium caused exudative lung injury that was reflected in increased cell counts and proteins in alveolar lavage fluid. The peak injury occurred at 16 hours after instillation, whereas recovery occurred by 72 hours. Although total lavage fluid phospholipids did not change over time, phospholipid and dipalmitoyl phosphatidylcholine in large aggregates tended to decrease at 24 hours. Western blot analysis demonstrated time-dependent qualitative decreases in surfactant proteins A and B (SP-A, SP-B) in meconium-instilled animals compared with the controls. ELISA for SP-B confirmed the Western blot findings with total SP-B in large aggregate decreasing from 25 +/- 4 microg in controls to 6.6 +/- 0.8 microg at 24 hours of injury. CONCLUSIONS: Our study suggests that the exudative lung injury with meconium instillation is associated with decreased levels of SP-A and SP-B in the large aggregate fraction of lung surfactant. We speculate that decreased secretion and/or increased degradation accounts for lower levels of SP-B in bronchoalveolar lavage fluid. 相似文献
746.
Ruud Oudega Karel GM Moons H Karel Nieuwenhuis Fred L van Nierop Arno W Hoes 《The British journal of general practice》2006,56(530):693-696
BACKGROUND: The increased prevalence of unrecognised malignancy in patients with deep vein thrombosis (DVT) has been well established in secondary care settings. However, data from primary care settings, needed to tailor the diagnostic workup, are lacking. AIM: To quantify the prevalence of unrecognised malignancy in primary care patients who have been diagnosed with DVT. DESIGN: Prospective follow-up study. SETTING: All primary care physicians affiliated/associated with a non-teaching hospital in a geographically circumscribed region participated in the study. METHOD: A total of 430 consecutive patients without known malignancy, but with proven DVT were included in the study and compared with a control group of 442 primary care patients, matched according to age and sex. Previously unrecognised, occult malignancy was considered present if a new malignancy was diagnosed within 2 years following DVT diagnosis (DVT group) or inclusion in the control group. Patients with DVT were categorised in to those with unprovoked idiopathic DVT and those with risk factors for DVT (that is, secondary DVT). RESULTS: During the 2-year follow-up period, a new malignancy was diagnosed 3.6 times more often in patients with idiopathic DVT than in the control group (2-year incidence: 7.4% and 2.0%, respectively). The incidence in patients with secondary DVT was 2.6%; only slightly higher than in control patients. CONCLUSION: Unrecognised malignancies are more common in both primary and secondary care patients with DVT than in the general population. In particular, patients with idiopathic DVT are at risk and they could benefit from individualised case-finding to detect malignancy. 相似文献
747.
We studied the diagnostic predictive power of transrectal ultrasonography
(TRUS) coupled with semen volume in cases of distal seminal tract
sub-obstruction. As a gold standard for diagnosis we used seminal tract
washout (STW). Non-azoospermic subjects (n = 112) were submitted to
transrectal ultrasonography because of suspected excretory infertility or
other andrological pathologies, before performing STW. STW indicated
ejaculatory duct sub-obstruction in 36.6% of the patients. Seminal vesicle
enlargement (anterior-posterior diameter > or = 15 mm) and seminal
vesicle roundish anechoic areas (stasis) were the ultrasonographic
anomalies more often associated with ejaculatory duct sub-obstruction.
Stepwise logistic regression (SLR) analysis revealed that the
ultrasonographic evidence of stasis was highly diagnostic only in the
presence of a low semen volume (< or = 1.5 ml) and that ejaculatory duct
sub-obstructions may be present but with no evidence of ultrasonographic
anomalies. Therefore, TRUS is a useful approach for the treatment of
suspected ejaculatory duct sub-obstruction, but is not a reliable
diagnostic tool and, before performing transurethral surgery, STW should be
mandatory.
相似文献
748.
van den Berg JM Mul FP Schippers E Weening JJ Roos D Kuijpers TW 《European journal of immunology》2001,31(1):276-284
Although the importance of beta1 integrin-mediated binding to adhesion molecules and extracellular matrix (ECM) molecules is well established for most types of leukocytes, the expression patterns and functional importance of beta1 integrins on neutrophils have remained controversial. Using flow cytometry, we found that human neutrophils express the alpha4, alpha5, alpha9 and beta1 integrin subunits. To examine whether the integrins VLA-4 (alpha4/beta1) and VLA-5 (alpha5/beta1) have a functional role on neutrophils, we studied adhesion to their ligand fibronectin. Treatment of neutrophils with antibody 8A2, which specifically binds and activates beta1 integrins, resulted in increased binding to fibronectin. However, addition of blocking mAb revealed that 8A2-induced adhesion did not depend on beta1 integrins, but on the beta2 integrin CD11b/CD18. Similarly, activation of beta1 integrins by 8A2 resulted in CD11b-dependent binding of neutrophils to fibrinogen. 8A2 treatment increased expression of an activation epitope of CD11b/CD18, which depended on phosphoinositide 3-OH kinase activity and an adequate concentration of intracellular free Ca2+. These data suggest that engagement of beta1 integrins on neutrophils results in a cross-talk signal that leads to activation of the beta2 integrin CD11b/CD18, followed by CD11b-mediated adhesion. As transmigrated neutrophils are surrounded by both beta1 and beta2 ligands in the ECM, this integrin cross-talk could play a role in modifying migration and cellular activation in inflamed tissues. 相似文献
749.
Dell'Aquila ME; Cho YS; Minoia P; Traina V; Lacalandra GM; Maritato F 《Human reproduction (Oxford, England)》1997,12(12):2766-2772
The aim of this study was to compare the effect of the addition of
follicular fluid (FF) collected from preovulatory follicles with that of
oestrous mare serum (EMS) (acting as the control) to TCM-199 medium on the
in-vitro maturation, fertilization and development of equine
cumulus-enclosed oocytes. Oocytes (<30 mm in diameter) were obtained
from the ovaries of slaughtered mares. After in-vitro maturation in the
presence of the two supplements, their fertilization, cleavage and
developmental potential were compared after conventional in-vitro
fertilization (IVF) or intracytoplasmic sperm injection (ICSI) using
frozen-thawed spermatozoa. Follicular fluid did not increase the maturation
of oocytes to metaphase II stage compared to control. After IVF, there was
no difference in fertilization rates between FF- supplemented oocytes and
controls (7/87, 8.4% of oocytes showing two pronuclei with FF versus 7/116,
6% with EMS; not significant). However, after ICSI, FF-supplemented oocytes
showed significantly increased normal fertilization (32/85, 37.6% of
two-pronuclear oocytes) and developmental potential (15/31, 48% cleavage)
compared to the control oocytes (7/47, 14.9%, P < 0.01; and 2/48, 4%, P
< 0.01, respectively). Overall, ICSI resulted in increased fertilization
rates compared to IVF, regardless of the presence or absence of FF (39/132,
29.5% with ICSI versus 14/203, 6.9%). These results suggest that follicular
fluid supplementation may improve the maturity of equine cumulus-enclosed
oocytes sufficiently for the successful use of ICSI, but not sufficiently
for normal sperm-egg interaction occurring during IVF.
相似文献
750.
Genetic susceptibility for human familial essential hypertension in a region of homology with blood pressure linkage on rat chromosome 10 总被引:9,自引:3,他引:9
Julier C; Delepine M; Keavney B; Terwilliger J; Davis S; Weeks DE; Bui T; Jeunemaitre X; Velho G; Froguel P; Ratcliffe P; Corvol P; Soubrier F; Lathrop GM 《Human molecular genetics》1997,6(12):2077-2085
Hypertension is a significant risk factor for heart attack and stroke and
represents a major public health burden because of its high prevalence
(e.g. 15-20% of the European and American populations). Although blood
pressure is known to have a strong genetic determination, the genes
responsible for susceptibility to essential hypertension are mostly
unknown. Loci involved in blood pressure regulation have been found by
linkage in experimental hereditary hypertensive rat strains, but their
relationship to human hypertension has not been extensively investigated.
One of the principal blood pressure loci has been mapped to rat chromosome
10 and we have undertaken an investigation of the homologous region on
human chromosome 17 in familial essential hypertension. Affected sib-pair
analysis and parametric analysis with ascertainment correction gave
significant evidence of linkage ( P <0.0001 in some analyses) near two
closely linked microsatellite markers, D17S183 and D17S934, that reside 18
cM proximal to the ACE locus in the homology region. Our results indicate
that chromosome 17q could contain a susceptibility locus for human
hypertension and show that comparative mapping may be a useful approach for
identification of such loci in humans.
相似文献