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191.
192.
Assessment of the proliferative,apoptotic and cellular renovation indices of the human mammary epithelium during the follicular and luteal phases of the menstrual cycle 总被引:1,自引:0,他引:1
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Navarrete MA Maier CM Falzoni R Quadros LG Lima GR Baracat EC Nazário AC 《Breast cancer research : BCR》2005,7(3):R306-R313
Introduction
During the menstrual cycle, the mammary gland goes through sequential waves of proliferation and apoptosis. In mammary epithelial cells, hormonal and non-hormonal factors regulate apoptosis. To determine the cyclical effects of gonadal steroids on breast homeostasis, we evaluated the apoptotic index (AI) determined by terminal deoxynucleotidyl transferase-mediated dUTP nick end labeling (TUNEL) staining in human mammary epithelial cells during the spontaneous menstrual cycle and correlated it with cellular proliferation as determined by the expression of Ki-67 during the same period. 相似文献193.
Pregnancy with concomitant chorangioma and placental vascular malformation with mesenchymal hyperplasia 总被引:2,自引:1,他引:2
Chen CP; Chern SR; Wang TY; Huang ZD; Huang MC; Chuang CY 《Human reproduction (Oxford, England)》1997,12(11):2553-2556
We present two pregnancies associated with normal live births and the
unusual concomitance of chorangioma and placental vascular malformation
with mesenchymal hyperplasia. The enlarged placenta had the characteristic
findings of chorangioma, dilated and varicose chorionic vessels and
multiple vesicle-like villi containing hyaluronic acid. The vesicle-like
villi showed diploid cellular DNA contents. Molecular genetic analysis
using the polymerase chain reaction amplification of polymorphic
microsatellite markers confirmed genetic identity among the chorangioma,
the vesicle-like villi and the fetus. Both pregnancies were complicated by
polyhydramnios, pre-term labour and prematurity. One neonate suffered from
anaemia and thrombocytopenia. Another neonate suffered from
haemangiomatosis. Our cases demonstrate that concomitant chorangioma and
placental mesenchymal hyperplasia are genetically identical to the fetus
and can coexist with a normal viable fetus. Since haemangiomas,
chorangiomas, chorionic vessels and villi mesenchymal cells are all derived
from the mesoderm, a combination of fetal haemangiomas, placental vascular
malformation, chorangiomas and placental mesenchymal hyperplasia may
represent a mixed form of congenital malformation of the mesoderm.
相似文献
194.
Medroxyprogesterone acetate with Zoladex for long-term treatment of fibroids: effects on bone density and patient acceptability 总被引:1,自引:0,他引:1
Caird LE; West CP; Lumsden MA; Hannan WJ; Gow SM 《Human reproduction (Oxford, England)》1997,12(3):436-440
A randomized trial was carried out to investigate the effect of 12 months
administration of the gonadotrophin-releasing hormone agonist (GnRHa)
Zoladex in combination with either placebo or medroxyprogesterone acetate
(MPA) from the third month. Bone density, markers of bone resorption,
symptoms and uterine volume were monitored in 24 women with symptomatic
fibroids or menstrual problems. A total of 21 women were recruited to act
as controls for the assessment of bone parameters. Vasomotor side-effects
were reduced significantly in the MPA-treated group. The reduction in
uterine volume in women with fibroids was not impaired by the addition of
MPA. The bone markers osteocalcin and alkaline phosphatase were assessed in
plasma, and the cross-links pyridinoline and deoxypyridinoline measured in
urine. Changes in these markers are reported which suggest increases in
bone resorption during the period of observation. Bone mineral density
(BMD) was assessed by dual energy X-ray absorptiometry at the spine and
forearm. The net reduction in BMD at the spine in the treated groups was
4.30 +/- 0.59% at 6 months and 7.50 +/- 0.78% at 1 year, with no change in
the control group. No change was seen in forearm BMD. No protective effect
was observed when MPA was added. At 1 year after the completion of
treatment, BMD remained significantly below baseline, and this has
implications for the prolonged use of GnRHa.
相似文献
195.
ES Petherick S O'Meara K Spilsbury CP Iglesias EA Nelson DJ Torgerson 《BMC medical research methodology》2006,6(1):43-4
Background
A trial was commissioned to evaluate the effectiveness of larval therapy to debride and heal sloughy and necrotic venous leg ulcers. Larval therapy in the trial was to be delivered in either loose or bagged form. Researchers were concerned that resistance to larval therapy may threaten the feasibility of the trial. Additionally there was concern that the use of larval therapy may require a larger effect size in time to healing than originally proposed by the investigators. 相似文献196.
Talbot K; Ponting CP; Theodosiou AM; Rodrigues NR; Surtees R; Mountford R; Davies KE 《Human molecular genetics》1997,6(3):497-500
The Survival Motor Neuron (SMN) gene shows deletions in the majority of
patients with Spinal Muscular Atrophy (SMA), a disease of motor neuron
degeneration. To date only two missense mutations have been reported in SMN
in patients with SMA. The fact that no SMN-homologues have been forthcoming
from data-base searching has resulted in a lack of hypotheses concerning
the structural and functional consequences of these mutations. Recently SMN
has been shown to interact with heterogeneous nuclear ribonucleoproteins
(hnRNPs) suggesting a role in mRNA metabolism. We describe a novel missense
mutation and the subsequent identification of a triplicated
tyrosine-glycine (Y-G) peptide sequence at the C-terminal of SMN which
encompasses each of the three predicted amino acid sequence substitutions.
We have identified apparent orthologues of SMN in Caenorhabditis elegans
and Schizosaccharomyces pombe. These sequences retain the highly conserved
Y-G motif and provide additional support for a role of SMN in mRNA
metabolism.
相似文献
197.
Nazife Baykal James A. Reogia Nese Yalabik Aydan Erkmen M.Sinan Beksac 《Computers in biology and medicine》1996,26(6):451-462
Doppler umbilical artery blood flow velocity waveform measurements are used in perinatal surveillance for the evaluation of fetal condition. There is an ongoing debate on the predictive value of Doppler measurements concerning the critical effect of the selection of parameters for the interpretation of Doppler waveforms. In this paper, we describe how neural network methods can be used both to discover relevant classification features and subsequently to classify Doppler umbilical artery blood flow velocity waveforms. Results obtained from 199 normal and high risk patients' umbilical artery waveforms highlighted a classification concordance varying from 90 to 98% accuracy. 相似文献
198.
199.
Genetic mapping of a major susceptibility locus for juvenile myoclonic epilepsy on chromosome 15q 总被引:5,自引:0,他引:5
Elmslie FV; Rees M; Williamson MP; Kerr M; Kjeldsen MJ; Pang KA; Sundqvist A; Friis ML; Chadwick D; Richens A; Covanis A; Santos M; Arzimanoglou A; Panayiotopoulos CP; Curtis D; Whitehouse WP; Gardiner RM 《Human molecular genetics》1997,6(8):1329-1334
The epilepsies are a group of disorders characterised by recurrent seizures
caused by episodes of abnormal neuronal hyperexcitability involving the
brain. Up to 60 million people are affected worldwide and genetic factors
may contribute to the aetiology in up to 40% of patients. The most common
human genetic epilepsies display a complex pattern of inheritance. These
are categorised as idiopathic in the absence of detectable structural or
metabolic abnormalities. Juvenile myoclonic epilepsy (JME) is a distinctive
and common variety of familial idiopathic generalised epilepsy (IGE) with a
prevalence of 0.5- 1.0 per 1000 and a ratio of sibling risk to population
prevalence (lambda(s)) of 42. The molecular genetic basis of these familial
idiopathic epilepsies is entirely unknown, but a mutation in the gene
CHRNA4, encoding the alpha4 subunit of the neuronal nicotinic acetylcholine
receptor (nAChR), was recently identified in a rare Mendelian variety of
idiopathic epilepsy. Chromosomal regions harbouring genes for nAChR
subunits were therefore tested for linkage to the JME trait in 34
pedigrees. Significant evidence for linkage with heterogeneity was found to
polymorphic loci encompassing the region in which the gene encoding the
alpha7 subunit of nAChR (CHRNA7) maps on chromosome 15q14 (HLOD = 4.4 at
alpha = 0.65; Z(all) = 2.94, P = 0.0005). This major locus contributes to
genetic susceptibility to JME in a majority of the families studied.
相似文献
200.
Purification and characterization of 26S proteasomes from human and mouse spermatozoa 总被引:4,自引:2,他引:4
Tipler CP; Hutchon SP; Hendil K; Tanaka K; Fishel S; Mayer RJ 《Molecular human reproduction》1997,3(12):1053-1060
We purified by fractionation on 10-40% glycerol gradients, 26S proteasomes
from normal human spermatozoa. These proteasomes, which participate in the
ATP-dependent degradation of ubiquitinated proteins, share a similar
sedimentation coefficient to those purified from other human tissues.
Fluorogenic peptide assays reveal they have chymotrypsin, trypsin and
peptidyl-glutamyl-like peptide hydrolysing activities; the chymotrypsin
activity is ablated by the specific 26S proteasome inhibitor MG132.
Confirmation that these large proteases are 26S proteasomes is provided by
detection of the 20S proteasome subunits HC2, XAPC7, RN3 and Z and
regulatory ATPases MSS1, TBP1, SUG1 and SUG2 by Western analyses with
monoclonal antisera. These antigens are found only in the gradient
fractions enriched in proteolytic activities. We have also shown that,
although mature spermatozoa from mice have considerably reduced amounts of
a ubiquitin-conjugating enzyme (E2) and ubiquitin-protein conjugates in
comparison with less mature germ cells, they retain relatively high values
of 26S proteasome activity. This suggests that proteasomes may have further
roles to play in normal sperm physiology.
相似文献