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21.
D K Robie R H Pearl C Gonsales R D Restuccia M A Hoffman 《Journal of pediatric surgery》1991,26(8):971-3; discussion 973-4
A case is reported of recurrent laryngotracheoesophageal cleft following two attempted repairs. The anterior approach to the larynx and trachea provided excellent exposure for defining the extent of the recurrent cleft, and allowed precise anatomic repair. Neurovascular structures were easily avoided by this operative method. Of 170 clefts reported in the literature, 19 recurred necessitating reoperation. The anterior approach to the larynx and trachea is appropriate in recurrent clefts and may be preferable at the initial repair. 相似文献
22.
W. Pearl 《Pediatric cardiology》1996,17(3):135-136
The objective of this study was to determine if gender, age, and heart rate affect corrected QT intervals in children. Electrocardiograms
were obtained from 781 healthy children 10–18 years of age. Corrected QT intervals were significantly (p < 0.0005) greater for girls than for boys in the entire population and for each age group over 14 years. The corrected QT
interval varied inversely with age and directly with heart rate. Hence gender, age, and heart rate should be considered when
diagnosing long QT syndrome. 相似文献
23.
Kumar S Nagl S Kalsi JK Ravirajan CT Athwal D Latchman DS Pearl LH Isenberg DA 《Molecular immunology》2005,42(1):39-48
We have recently shown that the anti-cardiolipin activity of human anti-phospholipid antibody UK4 (lambda) resides on its heavy chain. We now show that UK4 possesses strong reactivity to the plasma-protein beta2-Glycoprotein I (beta2-GPI) also. Utilizing chain shuffling experiments involving an unrelated anti-p185 antibody 4D5 (kappa) with no reactivity to beta2-GPI, we now demonstrate that both the constructs possessing the auto-antibody-derived light chain exhibited significant binding to beta2-GPI. However, the construct possessing UK4 heavy chain in association with 4D5 light chain, exhibited no anti-beta2-GPI activity. Furthermore, there was a low increase (approximately 10%) in the binding of UK4 to cardiolipin in the presence of beta2-GPI. The results demonstrate that anti-beta2-GPI activity resides on UK4 light chain and, importantly, this activity could be transferred to a novel antibody construct via the light chain alone. Computer-generated models of the three-dimensional structures of UK4 and its hybrids, suggest predominant interaction of UK4 light chain with domain IV of beta2-GPI. Molecular docking experiments highlight a number of potential sites on beta2-GPI for interaction of UK4 and indicate as to how beta2-GPI recognition may occur primarily via the autoantibody light chain. The study provides first demonstration of the occurrence of anti-phospholipid and anti-beta2-GPI activities separately on heavy and light chains of an autoantibody. The possible mechanisms that such antibodies may employ to recognise their antigens, are discussed. 相似文献
24.
Amy H. Kim Paul M. Macev Ph.D. Mary A. Woo Pearl L. Yu Thomas G. Keens David Gozal Ronald M. Harper 《Somnologie - Schlafforschung und Schlafmedizin》2002,6(3):109-115
Summary Question of the Study Congenital central hypoventilation syndrome (CCHS) subjects exhibit diminished respiratory-related heart rate variation in addition to defining characteristics of CO2 insensitivity and reduced ventilatory drive during sleep. Loss of cardiovascular and breathing coupling may diminish blood pressure influences on breathing; such influences may be determined by evaluating cardiorespiratory responses to different pressor challenges.
Patients and Methods Ten children with CCHS and 10 age- and gender-matched controls were subjected to a forehead cold pressor challenge and to Valsalva maneuvers. Heart and respiratory rates and variability during 30-s baseline and 120-s challenge periods were assessed with scatterplot displays and by analysis of variance procedures.
Results Cold pressor challenges enhanced breathing efforts and increased respiratory-related heart rate variation in controls but not in CCHS patients, while lower frequency heart rate variability increased in both controls and CCHS subjects. Heart rate variation resulting from voluntary expiratory efforts was present but slightly reduced in CCHS. Respiratory and cardiac rate trends differed in control and CCHS cases.
Conclusions More-rapidly changing heart rate variation from spontaneous or reflexively-induced sources is diminished in CCHS but remains intact from voluntary expiratory efforts, as does slower variation. Loss of reflexive influences on breathing from blood pressure changes may attenuate a source of respiratory drive. 相似文献
Patients and Methods Ten children with CCHS and 10 age- and gender-matched controls were subjected to a forehead cold pressor challenge and to Valsalva maneuvers. Heart and respiratory rates and variability during 30-s baseline and 120-s challenge periods were assessed with scatterplot displays and by analysis of variance procedures.
Results Cold pressor challenges enhanced breathing efforts and increased respiratory-related heart rate variation in controls but not in CCHS patients, while lower frequency heart rate variability increased in both controls and CCHS subjects. Heart rate variation resulting from voluntary expiratory efforts was present but slightly reduced in CCHS. Respiratory and cardiac rate trends differed in control and CCHS cases.
Conclusions More-rapidly changing heart rate variation from spontaneous or reflexively-induced sources is diminished in CCHS but remains intact from voluntary expiratory efforts, as does slower variation. Loss of reflexive influences on breathing from blood pressure changes may attenuate a source of respiratory drive. 相似文献
25.
Wong WW Doyle TC Cheung P Olson TM Reisler E 《Journal of muscle research and cell motility》2001,22(8):665-674
The molecular mechanisms by which different mutations in actin lead to distinct cardiomyopathies are unknown. Here, actin
mutants corresponding to α-cardiac actin mutations causing hypertrophic cardiomyopathy [(HCM) P164A and A331P] and dilated
cardiomyopathy [(DCM) R312H and E361G] were expressed in yeast and purified for in vitro functional studies. While P164A appeared unaltered compared to wild-type (WT) actin, A331P function was impaired. A331P showed
reduced stability in circular dichroism melting experiments; its monomer unfolding transition was 10°C lower compared to WT
actin. Additionally, in vitro filament formation was hampered, and yeast cell cultures were temperature sensitive, implying perturbations in actin–actin
interactions. Filament instability of the A331P mutant actin could lead to actomyosin dysfunction observed in HCM. Yeast strains
harboring the R312H mutation did not grow well in culture, suggesting that cell viability is compromised. The E361G substitution
is located at an α-actinin binding region where the actin filament is anchored. The mutant actin, though unaltered in the
in vitro motility and standard actomyosin functions, had a threefold reduction in α-actinin binding. This could result in impairment
of force-transduction in muscle fibers, and a DCM phenotype.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
26.
本文在国内首次报道了纤维素固相RIA法测定甲胎蛋白。本法简便灵敏,快迅稳定,平均回收率95.7±8.08%,批间变异系数r=7.8±1.7%,批内变异系数r=5.8±2.6%,线性关系较好(r=0.999),灵敏度比液相RIA提高6倍,32份血样品用双位点夹心法和试剂盒的液相RIA进行比较,结果经统计学处理,相关系数分别为r=0.82,r=0.80,均具有显著相关性。 相似文献
27.
Mutation spectrum and genotype-phenotype analyses in Cowden disease and Bannayan-Zonana syndrome, two hamartoma syndromes with germline PTEN mutation 总被引:22,自引:1,他引:22
Marsh DJ; Coulon V; Lunetta KL; Rocca-Serra P; Dahia PL; Zheng Z; Liaw D; Caron S; Duboue B; Lin AY; Richardson AL; Bonnetblanc JM; Bressieux JM; Cabarrot-Moreau A; Chompret A; Demange L; Eeles RA; Yahanda AM; Fearon ER; Fricker JP; Gorlin RJ; Hodgson SV; Huson S; Lacombe D; Eng C 《Human molecular genetics》1998,7(3):507-515
The tumour suppressor gene PTEN , which maps to 10q23.3 and encodes a 403
amino acid dual specificity phosphatase (protein tyrosine phosphatase;
PTPase), was shown recently to play a broad role in human malignancy.
Somatic PTEN deletions and mutations were observed in sporadic breast,
brain, prostate and kidney cancer cell lines and in several primary tumours
such as endometrial carcinomas, malignant melanoma and thyroid tumours. In
addition, PTEN was identified as the susceptibility gene for two hamartoma
syndromes: Cowden disease (CD; MIM 158350) and Bannayan-Zonana (BZS) or
Ruvalcaba-Riley-Smith syndrome (MIM 153480). Constitutive DNA from 37 CD
families and seven BZS families was screened for germline PTEN mutations.
PTEN mutations were identified in 30 of 37 (81%) CD families, including
missense and nonsense point mutations, deletions, insertions, a
deletion/insertion and splice site mutations. These mutations were
scattered over the entire length of PTEN , with the exception of the first,
fourth and last exons. A 'hot spot' for PTEN mutation in CD was identified
in exon 5 that contains the PTPase core motif, with 13 of 30 (43%) CD
mutations identified in this exon. Seven of 30 (23%) were within the core
motif, the majority (five of seven) of which were missense mutations,
possibly pointing to the functional significance of this region. Germline
PTEN mutations were identified in four of seven (57%) BZS families studied.
Interestingly, none of these mutations was observed in the PTPase core
motif. It is also worthy of note that a single nonsense point mutation,
R233X, was observed in the germline DNA from two unrelated CD families and
one BZS family. Genotype-phenotype studies were not performed on this small
group of BZS families. However, genotype-phenotype analysis inthe group of
CD families revealed two possible associations worthy of follow-up in
independent analyses. The first was an association noted in the group of CD
families with breast disease. A correlation was observed between the
presence/absence of a PTEN mutation and the type of breast involvement
(unaffected versus benign versus malignant). Specifically and more
directly, an association was also observed between the presence of a PTEN
mutation and malignant breast disease. Secondly, there appeared to be an
interdependent association between mutations upstream and within the PTPase
core motif, the core motif containing the majority of missense mutations,
and the involvement of all major organ systems (central nervous system,
thyroid, breast, skin and gastrointestinal tract). However, these
observations would need to be confirmed by studying a larger number of CD
families.
相似文献
28.
Reported complications rates for the construction of intestinal stomas are high. Many of these complications result from improper construction, improper location, or other technical errors. In order to sample the techniques of stoma construction currently in use, a survey was conducted at the 69th Annual Clinical Congress of the American College of Surgeons in Atlanta in conjunction with our scientific exhibit "Complications of Intestinal Stomas." A total of 245 surgeons completed the questionnaire with a mean age of 47.8 years. The routine use of fascial-seromuscular tacking sutures and primary maturation of a loop colostomy in the presence of distal obstruction were among the most controversial technical points considered. Many other subtle but important principles of stoma construction were also discussed. In addition, the authors contend that many of the techniques currently in use result from an underemphasis on the importance of proper stoma construction in many surgical training programs. 相似文献
29.
Dynamic CT features of hepatic abscesses 总被引:31,自引:0,他引:31
Forty hepatic abscesses were examined with dynamic computed tomography (CT). A "double target sign," consisting of a hypodense central area surrounded by first a hyperdense ring and then a hypodense zone, seems to be highly suggestive of abscess formation. In 12 cases, the hepatic parenchyma surrounding the lesion demonstrated transient hyperdensity after contrast injection, possibly due to localized hepatic venous obstruction secondary to acute hepatic inflammation. This is similar to the appearance of an arterioportal fistula. 相似文献
30.
Shilyansky J Navarro O Superina RA Babyn PS Filler RM Pearl RH 《Journal of pediatric surgery》1999,34(1):60-64
PURPOSE: Nonoperative management of blunt hepatic injury (BHI) has become widely accepted in hemodynamically stable children without ongoing transfusion requirements. However, late hemorrhage, especially after discharge from the hospital can be devastating. The authors report the occurrence of serious late hemorrhage and the sentinel signs and symptoms in children at risk for this complication. METHODS: Nonoperative management of hemodynamically stable children included computed tomography (CT) evaluation on admission and hospitalization with bed rest for 7 days, regardless of injury grade. Activity was restricted for 3 months after discharge. Hepatic injuries were classified according to grade, amount of hemoperitoneum, and periportal hypoattenuation. RESULTS: Over 5 years, nonoperative management was successful in 74 of 75 children. One child returned to the hospital 3 days after discharge with recurrent hemorrhage necessitating surgical control. Review of the CT findings demonstrated that he was the only child with severe liver injury in all four classifications. A second child, initially treated at an outside hospital, presented 10 days after injury with ongoing bleeding and died despite surgical intervention. Only the two children with delayed bleeding had persistent right abdominal and shoulder discomfort in the week after BHI. CONCLUSIONS: Our findings support nonoperative management of BHI. However, late hemorrhage heralded by persistence of right abdominal and shoulder pain may occur in children with severe hepatic trauma and high injury severity scores in multiple classifications. 相似文献