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排序方式: 共有974条查询结果,搜索用时 15 毫秒
31.
Subramanyam L, Simha V, Garg A. Overlapping syndrome with familial partial lipodystrophy, Dunnigan variety and cardiomyopathy due to amino‐terminal heterozygous missense lamin A/C mutations. Familial partial lipodystrophy, Dunnigan variety (FPLD) is a well‐recognized autosomal dominant disorder due to heterozygous missense mutations in lamin A/C (LMNA) gene. Most of the FPLD patients harbor mutations in the C‐terminal of the lamin A/C and do not develop cardiomyopathy. On the other hand, affected subjects from three FPLD pedigrees with heterozygous R28W, R60G and R62G LMNA mutations in the amino‐terminal had associated cardiomyopathy presenting as premature onset of congestive heart failure, dilated cardiomyopathy and conduction system disturbances. We report three new FPLD pedigrees presenting with cardiomyopathy associated with heterozygous LMNA mutations in the amino‐terminal region. Two of them had previously reported R60G and R62G mutations and one has a novel D192V mutation. Affected subjects belonging to the pedigree with heterozygous R62G mutation had atrial fibrillation and required pacemaker implantation. The affected subjects from the other pedigrees with R60G and D192V mutations developed severe cardiomyopathy requiring defibrillator implantation and cardiac transplantation before 30 years of age in some and premature death in the fourth decade in others. Thus, our report provides further evidence of association of a multisystem dystrophy syndrome in FPLD patients harboring amino‐terminal mutations in LMNA. Increased understanding of the genotype–phenotype association might help devise clinical strategies aimed at preventing devastating manifestations of cardiomyopathy including heart failure, arrhythmias and sudden death. Furthermore, the underlying molecular mechanisms by which these amino‐terminal mutations cause lipodystrophy as well as cardiomyopathy remain to be understood. 相似文献
32.
DL?MagerEmail author AD?Haffajee PM?Devlin CM?Norris MR?Posner JM?Goodson 《Journal of translational medicine》2005,3(1):27
Background
The purpose of the present investigation was to determine if the salivary counts of 40 common oral bacteria in subjects with an oral squamous cell carcinoma (OSCC) lesion would differ from those found in cancer-free (OSCC-free) controls. 相似文献33.
Debelenko LV; Brambilla E; Agarwal SK; Swalwell JI; Kester MB; Lubensky IA; Zhuang Z; Guru SC; Manickam P; Olufemi SE; Chandrasekharappa SC; Crabtree JS; Kim YS; Heppner C; Burns AL; Spiegel AM; Marx SJ; Liotta LA; Collins FS; Travis WD; Emmert-Buck MR 《Human molecular genetics》1997,6(13):2285-2290
Lung carcinoids occur sporadically and rarely in association with multiple
endocrine neoplasia type 1 (MEN1). There are no well defined genetic
abnormalities known to occur in these tumors. We studied 11 sporadic lung
carcinoids for loss of heterozygosity (LOH) at the locus of the MEN1 gene
on chromosome 11q13, and for mutations of the MEN1 gene using dideoxy
fingerprinting. Additionally, a lung carcinoid from a MEN1 patient was
studied. In four of 11 (36%) sporadic tumors, both copies of the MEN1 gene
were inactivated. All four tumors showed the presence of a MEN1 gene
mutation and loss of the other allele. Observed mutations included a 1 bp
insertion, a 1 bp deletion, a 13 bp deletion and a single nucleotide
substitution affecting a donor splice site. Each mutation predicts
truncation or potentially complete loss of menin. The remaining seven
tumors showed neither the presence of a MEN1 gene mutation nor 11q13 LOH.
The tumor from the MEN1 patient showed LOH at chromosome 11q13 and a
complex germline MEN1 gene mutation. The data implicate the MEN1 gene in
the pathogenesis of sporadic lung carcinoids, representing the first
defined genetic alteration in these tumors.
相似文献
34.
Fifty women with polycystic ovaries took part in a prospective randomized
study. All women required treatment by in-vitro fertilization (IVF) for
reasons other than anovulation. They had all previously undergone ovarian
stimulation with gonadotrophin therapy which had failed to result in
pregnancy or had been abandoned due to high risk of developing ovarian
hyperstimulation syndrome (OHSS). Twenty-five women were treated by
long-term pituitary desensitization followed by gonadotrophin therapy,
oocyte retrieval and embryo transfer (group 1). Twenty-five women underwent
laparoscopic ovarian electrocautery after pituitary desensitization
followed by gonadotrophin therapy, oocyte retrieval and embryo transfer
(group 2). A significantly higher number of women in group 1 had to have
the treatment cycle abandoned due to impending or actual OHSS, determined
by endocrine and clinical findings. In addition, the development of
moderate or severe OHSS in completed cycles was higher in group 1. The
pregnancy rate and miscarriage rates in the two treatment groups were
similar. The authors propose that laparoscopic ovarian electrocautery is a
potentially useful treatment for women who have previously had an IVF
treatment cycle cancelled due to risk of OHSS or who have suffered OHSS in
a previous treatment cycle.
相似文献
35.
The bias favoring deletion over inversion in DH-JH rearrangement has been
known for years, but the underlying mechanism has yet to be fully defined.
It has been suggested that the ratio of deletion/inversion is determined by
the combined effect of two factors: (i) the relative strengths of 5' and 3'
recombination signal sequences (RSS) of a DH segment, and (ii) the
efficiency with which the deletional product (one joint) forms relative to
the inversional product (two joints). In this study, we analyzed for the
first time the effect of factor 1 alone on the biased 3' RSS utilization in
DH-JH joining by using deletional plasmids in an extrachromosomal substrate
V(D)J recombination assay. It was found that the 3' RSS and associated
coding end (12 bp) mediate recombination more efficiently than the 5'
RSS/coding end DH-JH plasmids. These results demonstrate that the effect of
the RSS/coding end alone can account, at least partially, for the
predominant deletion in DH-JH recombination. The potential effect of the
relative strength of RSS and associated coding end on the ordered
rearrangement of DH-JH followed by VH to DH-JH was also assessed. When
recombination frequencies of D-->J (3' DH to J3) were compared with
frequencies of V-- >D (VHPJ14 to 3' DH or VHOX2 to 3' DH), it was found
that V-->D joining was, if anything, more efficient than D-->J
joining. Therefore, if all three segments were accessible, RSS/coding end
effects would not contribute to the ordered rearrangement of the IgH locus.
相似文献
36.
In vitro evidence for both the nucleus and cytoplasm as subcellular sites of pathogenesis in Huntington's disease 总被引:6,自引:1,他引:6
A unifying feature of the CAG expansion diseases is the formation of
intracellular aggregates composed of the mutant polyglutamine-expanded
protein. Despite the presence of aggregates in affected patients, the
precise relationship between aggregates and disease pathogenesis is
unresolved. Results from in vivo and in vitro studies of mutant huntingtin
have lead to the hypothesis that nuclear localization of aggregates is
critical for the pathology of Huntington's disease (HD). We tested this
hypothesis using a 293T cell culture model system that compared the
frequency and toxicity of cytoplasmic and nuclear huntingtin aggregates. We
first assessed the mode of nuclear transport of N-terminal fragments of
huntingtin, and show that the predicted endogenous NLS is not functional,
providing data in support of passive nuclear transport. This result
suggests that proteolysis is a necessary step for nuclear entry of
huntingtin. Additionally, insertion of nuclear import or export sequences
into huntingtin fragments containing 548 or 151 amino acids was used to
reverse the normal localization of these proteins. Changing the subcellular
localization of the fragments did not influence their total aggregate
frequency. There were also no significant differences in toxicity
associated with the presence of nuclear compared with cytoplasmic
aggregates. The findings of nuclear and cytoplasmic aggregates in affected
brains, together with these in vitro data, support the nucleus and cytosol
as subcellular sites for pathogenesis in HD.
相似文献
37.
38.
39.
CJT De Amorim e Silva A Mackenzie LM Hallowell SE Stewart MR Ditchfield 《Journal of Medical Imaging and Radiation Oncology》2006,50(4):319-323
The aim of this study was to evaluate the effectiveness of a practice magnetic resonance unit, in preparing children to undergo magnetic resonance procedures without general anaesthesia (GA) or sedation. The records of children who attended the practice MRI between February 2002 and April 2004 were retrospectively reviewed. Each record was assessed as to whether the child had passed or failed the practice MRI intervention. Those children who were considered to have passed and were proceeded to a clinical non‐GA MRI had the report of the clinical scan reviewed. If the scan had been reported as non‐diagnostic because of movement artefact it was classified as a failed scan, otherwise it was considered a pass. One hundred and thirty‐four children undertook a practice MRI (age range 4.1–16.1 years, median age 7.7 years, 47% boys) and 120/134 (90%) passed the practice session. In all, 117/120 (98%) subsequently had a clinical non‐GA MRI and 110/117 (94%) passed (median age 7.8 years, 47% boys). Preparation is a safe and effective method to reduce the need for sedation and GA in children undergoing a clinical MRI scan. It provides a positive medical experience for children, parents and staff, and results in cost savings for the hospital. 相似文献
40.