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排序方式: 共有266条查询结果,搜索用时 15 毫秒
51.
52.
53.
Summary The growth of the porcine palcenta from 38 days until term is described. Measurements were made of its area, circumference and in situ length. Placental area increased during the period of study due to increases in the uterine circumference at the sites of conceptuses. No change was found in uterine horn length or placental length with age. Fetal weight correlated well with placental area but poorly with the other parameters. Placental length was shorter in more crowded horns and showed a U shaped distribution with position within uterine horns. These results are discussed in terms of competition for space within the uterus as a cause of the within litter variation in fetal size. 相似文献
54.
H. Tindall P. Martin D. Nagi S. Pinnock M. Stickland J.A. Davies 《Diabetic medicine》1994,11(1):37-41
Asian patients with diabetes have a higher prevalence of renal disease than their European counterparts. The aim of the study was to investigate the pattern of the renal excretion of proteins in 70 Asian and 70 European patients with diabetes and to relate it to dietary intake of protein and prevalence of diabetic complications. Compared with matched Europeans, Asian patients had an increased urinary excretion of albumin and transferrin (p < 0.02) with 14 Asians and 6 Europeans having significant microalbuminuria (> 30 μg min?1). In 12 Asians and all 6 Europeans this was associated with complications from diabetes, particularly vascular. Asian patients had significantly more ischaemic heart disease (p < 0.001) but less neuropathy (p < 0.001) and retinopathy (p < 0.05) than their matched European counterparts. Asian diets were lower in protein (median (range) Asian vs European: 12.5% (6–29%) vs 19% (11–27%); p <0.01) and carbohydrate but higher in fat than European diets. There was no correlation between dietary protein intake and excretion of any of the urinary proteins measured. However, a significant correlation was found in Asians between protein intake and length of residence in the UK (p < 0.005). Unless ways to reduce complications can be found then future allocation of resources will need to take this into consideration in areas with large Asian communities. 相似文献
55.
56.
Yates JR; van Bakel I; Sepp T; Payne SJ; Webb DW; Nevin NC; Green AJ 《Human molecular genetics》1997,6(13):2265-2269
We have investigated a family in which three siblings with the autosomal
dominant disorder tuberous sclerosis had unaffected parents. The family
were typed for polymorphic markers spanning the two genes known to cause
tuberous sclerosis located at 9q34 (TSC1) and 16p13.3 (TSC2). TSC1 markers
showed different maternal and paternal haplotypes in affected children,
excluding a mutation in TSC1 as the cause of the disease. For the TSC2
markers all the affected children had the same maternal and paternal
haplotypes, as did three of their unaffected siblings. Mutation screening
by RT-PCR and direct sequencing of the TSC2 gene identified a 4 bp
insertion TACT following nucleotide 2077 in exon 18 which was present in
the three affected children but not in five unaffected siblings or the
parents. This mutation would cause a frameshift and premature termination
at codon 703. Absence of the mutation in lymphocyte DNA from the parents
was consistent with germline mosaicism and this was confirmed by our
finding of identical chromosome 16 haplotypes in affected and unaffected
siblings, providing unequivocal evidence of two different cell lines in the
gametes. Molecular analysis of the TSC2 alleles present in the affected
subjects showed that the mutation had been inherited from the mother. This
is the first case of germline mosaicism in tuberous sclerosis proven by
molecular genetic analysis and also the first example of female germline
mosaicism for a characterized autosomal dominant gene mutation apparently
not associated with somatic mosaicism.
相似文献
57.
Deary AJ; Seaton JE; Prentice A; Morton NC; Booth AK; Smith SK 《Human reproduction (Oxford, England)》1997,12(7):1494-1496
Our objective was to evaluate the effect of a change in treatment
protocols, suggested following an inspection visit by the regulatory
authority, from single to double inseminations during donor insemination
treatment cycles. We therefore conducted a retrospective audit of pregnancy
rates in the reproductive medicine clinic of a major teaching hospital. All
patients were treated for male factor infertility by donor insemination,
without ovulation induction with gonadotrophins between October 1992 and
December 1995. The main outcome measures were cumulative conception and
live birth rates. During the study period 250 patients underwent treatment
and 650 single insemination and 277 double insemination treatment cycles
were undertaken. The pregnancy rate per cycle was 0.054 and 0.119 for
single and double insemination respectively. After six cycles the
cumulative pregnancy rates were 0.28 and 0.47 and the take-home baby rates
were 0.25 and 0.37 for single and double inseminations respectively. The
change in practice from single to double insemination resulted in a
doubling of the pregnancy rate per treatment cycle. Cumulative pregnancy
rates after two treatment cycles of double insemination were comparable
with those achieved after six cycles of single insemination. These results
have significant implications for both patients and purchasers.
相似文献
58.
Stéphanie A. Bayol Raymond Macharia Samantha J. Farrington Bigboy H. Simbi Neil C. Stickland 《European journal of nutrition》2009,48(1):62-65
Background Obesity is a multi-factorial condition generally attributed to an unbalanced diet and lack of exercise. Recent evidence suggests
that maternal malnutrition during pregnancy and lactation can also contribute to the development of obesity in offspring.
We have developed an animal model in rats to examine the effects of maternal overeating on a westernised “junk food” diet
using palatable processed foods rich in fat, sugar and salt designed for human consumption. Using this model, we have shown
that such a maternal diet can promote overeating and a greater preference for junk food in offspring at the end of adolescence.
The maternal junk food diet also promoted adiposity and muscle atrophy at weaning. Impaired muscle development may permanently
affect the function of this tissue including its ability to generate force.
Aims The aim of this study is to determine whether a maternal junk food diet can impair muscle force generation in offspring.
Methods Twitch and tetanic tensions were measured in offspring fed either chow alone (C) or with a junk food diet (J) during gestation,
lactation and/or post-weaning up to the end of adolescence such that three groups of offspring were used, namely the CCC,
JJC and JJJ groups.
Results We show that adult offspring from mothers fed the junk food diet in pregnancy and lactation display reduced muscle force (both
specific twitch and tetanic tensions) regardless of the post-weaning diet compared with offspring from mothers fed a balanced
diet.
Conclusions Maternal malnutrition can influence muscle force production in offspring which may affect an individual’s ability to exercise
and thereby combat obesity. 相似文献
59.
Automated sequencing detects all mutations in Northern Irish patients with phenylketonuria and mild hyperphenylalaninaemia 总被引:1,自引:0,他引:1
J Zschocke CA Graham FJ Stewart DJ Carson NC Nevin 《Acta paediatrica (Oslo, Norway : 1992)》1994,83(S407):37-38
In the first phase of the Northern Ireland PKU Study, we used automated sequencing to identify the spectrum of mutations in a random group of 32 unrelated phenylketonuria (PKU) families. We also investigated 7 Northern Irish patients with mild hyperphenylalaninaemia not requiring dietary intervention (MHP, previously referred to as non-PKU HPA). Disease-causing mutations were identified on all 78 investigated chromosomes. We found 23 different mutations, including 20 missense, 1 nonsense and 2 splice site mutations. All mutations were located within exons or at intronexon boundaries of the phenylalanine hydroxylase gene. Seven mutations occurred at CpG sites, confirming these sites as mutation hot-spots in PKU. Mutations R408W and I65T are the two commonest PKU mutations in the Northern Irish population. Two mutations (T380M and V245A) can be characterized as MHP mutations; they are quasi dominant markers for MHP since they cause mild hyperphenylalaninaemia even when occurring in conjunction with the most severe PKU mutations. The results have proven valuable for the development of a routine PKU mutation analysis system in Northern Ireland. 相似文献
60.
The Aalpha-fibrinogen Thr312Ala polymorphism, which occurs in a region involved in factor XIII (FXIII)-dependent cross-linking processes, is associated with poststroke mortality in subjects with atrial fibrillation, suggesting an influence either on intraatrial clot formation or embolization. We have determined the association of Thr312Ala with deep vein thrombosis (DVT) and pulmonary embolism (PE) and have assessed the interaction of Thr312Ala with the FXIII Val34Leu polymorphism in 122 patients with DVT, 99 patients with PE, and 254 healthy control subjects. The genotype distribution of patients with PE (TT = 49%, TA = 36%, AA = 15%), but not DVT (TT = 50%, TA = 42%, AA = 8%), differed significantly from healthy control subjects (TT = 60%, TA = 34%, AA = 6%, P =.02). A significant interaction of Thr312Ala and Val34Leu was also identified (P =.01), indicating an inverse association between Leu34 and Ala312. These results support the hypothesis that Thr312Ala alters FXIII-dependent cross-linking, making formed fibrin clot more susceptible to embolization. 相似文献