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排序方式: 共有479条查询结果,搜索用时 15 毫秒
21.
KA Hodgkinson SP Connors N Merner A Haywood T‐L Young WJ McKenna B Gallagher F Curtis AS Bassett PS Parfrey 《Clinical genetics》2013,83(4):321-331
To determine the phenotype and natural history of a founder genetic subtype of autosomal dominant arrhythmogenic right ventricular cardiomyopathy (ARVC) caused by a p.S358L mutation in TMEM43. The age of onset of cardiac symptoms, clinical events and test abnormalities were studied in 412 subjects (258 affected and 154 unaffected), all of which occurred in affected males significantly earlier and more often than unaffected males. Affected males were hospitalized four times more often than affected females (p ≤ 0.0001) and died younger (p ≤ 0.001). The temporal sequence from symptoms onset to death was prolonged in affected females by 1–2 decades. The most prevalent electrocardiogram (ECG) manifestation was poor R wave progression (PRWP), with affected males twice as likely to develop PRWP as affected females (p ≤ 0.05). Left ventricular enlargement (LVE) occurred in 43% of affected subjects, with 11% fulfilling criteria for dilated cardiomyopathy. Ventricular ectopy on Holter monitor was common and occurred early: the most diagnostically useful clinical test. No symptom or test could rule out diagnosis. This ARVC subtype is a sex‐influenced lethal arrhythmogenic cardiomyopathy, with a unique ECG finding, LV dilatation, heart failure and early death, where molecular pre‐symptomatic diagnosis has the greatest clinical utility. 相似文献
22.
PS Spencer K Vandemaele M Richer VS Palmer S Chungong M Anker Y Ayana ML Opoka BN Klaucke A Quarello JK Tumwine 《African health sciences》2013,13(2):183-204
Background
Nodding Syndrome is a seizure disorder of children in Mundri County, Western Equatoria, South Sudan. The disorder is reported to be spreading in South Sudan and northern Uganda.Objective
To describe environmental, nutritional, infectious, and other factors that existed before and during the de novo 1991 appearance and subsequent increase in cases through 2001.Methods
Household surveys, informant interviews, and case-control studies conducted in Lui town and Amadi village in 2001–2002 were supplemented in 2012 by informant interviews in Lui and Juba, South Sudan.Results
Nodding Syndrome was associated with Onchocerca volvulus and Mansonella perstans infections, with food use of a variety of sorghum (serena) introduced as part of an emergency relief program, and was inversely associated with a history of measles infection. There was no evidence to suggest exposure to a manmade neurotoxic pollutant or chemical agent, other than chemically dressed seed intended for planting but used for food. Food use of cyanogenic plants was documented, and exposure to fungal contaminants could not be excluded.Conclusion
Nodding Syndrome in South Sudan has an unknown etiology. Further research is recommended on the association of Nodding Syndrome with onchocerciasis/mansonelliasis and neurotoxins in plant materials used for food. 相似文献23.
Cu2+-tolerant/resistant (Cur) strain of the cyanobacterium Nostoc calcicola BRÉB ., developed in the laboratory, showed remarkable growth in ambient medium containing 40 μM Cu2+ (5 μM Cu2+ being lethal for wild type strain). It showed 22% less Cu2+ uptake compared to Cus (Cu-sensitive) cells. Cur cyanobacterial cells were characterized by a time-dependent Cu2+ efflux in contrast to no cation efflux by Cus cells. Cu2+ efflux pattern in Cur cells consisted of two distinct phases: First rapid efflux (10 min) followed by slower second one at least up to 1 h. Cu2+ efflux depended to a major extent on light generated ATP1), as the dark exposed Cur cells showed 87% reduction in Cu2+ efflux. The lowering in Cu2+ efflux in presence of various metabolic inhibitors/uncouplers like carbonyl cyanide-m-chloro phenyl hydrazone (CCCP)1), N,N'-dicyclohexycarbodiimide (DCCD), azide (NaN3) and p-chloromercuribenzoate (pCMB) indicated the involvement of -SH group, membrane potential and ATP hydrolysis in the regulation of this process. Cu2+ efflux was also initiated in such a medium containing 100-fold lower Cu2+ concentration (0.4 μM) compared to 40 μM Cu2+ (saturing concentration for metal uptake) and not before. It is suggested that Cu2+ efflux in N. calcicola cells may be the predominant mechanism of Cu2+ resistance/tolerance in this organism and are regulated at different levels by different modifying factors. 相似文献
24.
Distribution of mutations in the PEX gene in families with X-linked hypophosphataemic rickets (HYP) 总被引:8,自引:0,他引:8
Rowe PS; Oudet CL; Francis F; Sinding C; Pannetier S; Econs MJ; Strom TM; Meitinger T; Garabedian M; David A; Macher MA; Questiaux E; Popowska E; Pronicka E; Read AP; Mokrzycki A; Glorieux FH; Drezner MK; Hanauer A; Lehrach H; Goulding JN; O'Riordan JL 《Human molecular genetics》1997,6(4):539-549
Mutations in the PEX gene at Xp22.1 (phosphate-regulating gene with
homologies to endopeptidases, on the X-chromosome), are responsible for
X-linked hypophosphataemic rickets (HYP). Homology of PEX to the M13 family
of Zn2+ metallopeptidases which include neprilysin (NEP) as prototype, has
raised important questions regarding PEX function at the molecular level.
The aim of this study was to analyse 99 HYP families for PEX gene
mutations, and to correlate predicted changes in the protein structure with
Zn2+ metallopeptidase gene function. Primers flanking 22 characterised
exons were used to amplify DNA by PCR, and SSCP was then used to screen for
mutations. Deletions, insertions, nonsense mutations, stop codons and
splice mutations occurred in 83% of families screened for in all 22 exons,
and 51% of a separate set of families screened in 17 PEX gene exons.
Missense mutations in four regions of the gene were informative regarding
function, with one mutation in the Zn2+-binding site predicted to alter
substrate enzyme interaction and catalysis. Computer analysis of the
remaining mutations predicted changes in secondary structure,
N-glycosylation, protein phosphorylation and catalytic site molecular
structure. The wide range of mutations that align with regions required for
protease activity in NEP suggests that PEX also functions as a protease,
and may act by processing factor(s) involved in bone mineral metabolism.
相似文献
25.
E Waanders H Venselaar RHM Te Morsche DB De Koning PS Kamath VE Torres S Somlo JPH Drenth 《Clinical genetics》2010,78(1):47-56
Waanders E, Venselaar H, te Morsche RHM, de Koning DB, Kamath PS, Torres VE, Somlo S, Drenth JPH. Secondary and tertiary structure modeling reveals effects of novel mutations in polycystic liver disease genes PRKCSH and SEC63. Polycystic liver disease (PCLD) is characterized by intralobular bile duct cysts in the liver. It is caused by mutations in PRKCSH, encoding hepatocystin, and SEC63, encoding Sec63p. The main goals of this study were to screen for novel mutations and to analyze mutations for effects on protein structure and function. We screened 464 subjects including 76 probands by direct sequencing or conformation‐sensitive capillary electrophoresis. We analyzed the effects of all known and novel mutations using a combination of splice site recognition, evolutionary conservation, secondary and tertiary structure predictions, Poly Phen , and p Mut and sift . We identified a total of 26 novel mutations in PRKCSH (n = 14) and SEC63 (n = 12), including four splice site mutations, eight insertions/ deletions, six non‐sense mutations, and eight missense mutations. Out of 48 PCLD mutations, 13 were predicted to affect splicing. Most mutations were located in highly conserved regions and homology modeling for two domains of Sec63p showed severe effects of the residue substitutions. In conclusion, we identified 26 novel mutations associated with PCLD and we provide in silico analysis in order to delineate the role of these mutations. 相似文献
26.
Vandana Dixit A.K. Pati A.K. Gupta P.S. Bisen G.B.K.S. Prasad 《Journal of clinical laboratory analysis》2009,23(3):186-191
This study was aimed to elucidate the relationship between major blood group antigens (BGAs) and susceptibility or resistance to human lymphatic filariasis. A total of 492 human subjects, living in Raipur city of Chhattisgarh, endemic for bancroftian filariasis in Central India, were screened for the presence of Wuchereria bancrofti microfilariae and disease manifestations. The frequency of BGAs was tabulated as a function of the status of filariasis, namely normal (no infection), mf carrier (presence of microfilariae in blood), and elephantiasis (confirmed clinical manifestations). The comparison of ABO phenotype distributions among all the three groups clearly indicated that disease status has a significant relationship with the blood group attributes. The result of χ2 analysis of the frequencies of ABO phenotypes observed in microfilaraemic and elephantiasis groups (observed frequency vs. expected frequency computed based on the distribution of the normal population) revealed that there has been a significant alteration in the distribution of ABO phenotypes in microfilaraemic, but not in elephantiasis, group. The susceptibility to filarial infection was computed as a function of blood group phenotypes in the population. The susceptibility and conditional susceptibility for elephantiasis were the least among the subjects with AB phenotypes. The mechanism of association between filariasis and ABO antigens needs to be further explored to understand how the distribution of BGAs affects susceptibility/resistance to infection. J. Clin. Lab. Anal. 23:186–191, 2009. © 2009 Wiley‐Liss, Inc. 相似文献
27.
HW Schytz T Wienecke PS Oturai J Olesen & M Ashina 《Cephalalgia : an international journal of headache》2009,29(2):258-268
The parasympathetic nervous system is likely to be involved in migraine pathogenesis. We hypothesized that the cholinomimetic agonist carbachol would induce headache and vasodilation of cephalic and radial arteries. Carbachol (3 µg/kg) or placebo was randomly infused into 12 healthy subjects in a double-blind crossover study. Headache was scored on a verbal rating scale from 0–10. Velocity in the middle cerebral artery (VMCA ) and diameter of the superficial temporal artery (STA) and radial artery (RA) were recorded. Nine participants developed headache after carbachol compared with three after placebo. The area under the curve for headache was increased after carbachol compared with placebo both during infusion (0–30 min) ( P = 0.042) and in the postinfusion period (30–90 min) ( P = 0.027). Carbachol infusion caused a drop in VMCA ( P = 0.003) and an increase in STA diameter ( P = 0.006), but no increase in the RA diameter ( P = 0.200). In conclusion, the study demonstrated that carbachol caused headache and dilation of cephalic arteries in healthy subjects. 相似文献
28.
29.
Background: An outbreak of food poisoning in a military establishment mess was investigated and remedial measures suggested. 相似文献
30.
Deletion of the long arm of chromosome 6 (6q) is one of the most common chromosomal alterations in human B-cell lymphomas. Conventional cytogenetic banding analysis and loss-of-heterozygosity (LOH) studies have detected several common regions of deletion ranging across the entire long arm (6q), with no defined recurrent breakpoint yet identified. We describe here a strategy combining chromosome microdissection and fluorescence in situ hybridization (Micro-FISH) to determine a minimal region of deletion along chromosome 6. Seven clinical cases and one cell line of follicular lymphoma containing a t(14;18) and one case of diffuse lymphoma, also with a t(14;18), were used for this study. All nine cases had previously defined abnormalities of chromosome 6 determined by cytogenetic analysis. The results of chromosome dissection were unexpected and in contrast to the suggestion of disparate breakpoints by conventional chromosome banding. Specifically, Micro-FISH analysis provided evidence for a common breakpoint at 6q11 in seven of nine cases. After Micro-FISH analysis, all of the presumed simple deletions of chromosome 6 were carefully reanalyzed and shown to actually represent either nonreciprocal translocations (three cases), interstitial deletions (five cases), or isochromosome (one case). The recurrent proximal breakpoint (6q11) was detected in seven of nine cases, with the minimal region of deletion encompassing 6q11 to 6q21. By analogy to other tumor systems, the identification of recurring breakpoints within 6q11 may suggest that a gene(s) important to the genesis or progression of follicular lymphoma can be localized to this band region. 相似文献