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11.
J L Wright C Coppin B J Mullen J A Pare T F Rutherford H Ling A N Gerein R T Miyagishima J C Hogg 《Canadian journal of surgery》1986,29(3):205-208
Recent studies have shown that the survival of patients with lung cancer is improved if the tumour is resected before it becomes larger than 3 cm in diameter and before it spreads to lymph nodes. While this suggests a positive benefit from early detection, recent mass-screening studies have claimed that the benefit obtained from this procedure is illusory because it relates to a lead-time bias. This study reports the results of surgical resection of 143 primary lung cancers. The data confirmed that the predicted 5-year survival was greatest (74%) following resection of lesions that were less than 3 cm in diameter without node involvement. Analysis showed that the age of these patients was 63 +/- 8 years, the same as in patients with larger tumours and more extensive node involvement. This suggests that tumours progress rapidly from a stage at which resection is beneficial to stages at which it is not. Although it is desirable that tests predict the presence of small tumours, the high requirements for sensitivity and specificity at current prevalence rates for lung cancer make this goal impractical. 相似文献
12.
Relative carriage rates of nuclear dehydrogenating clostridia in two populations of different colorectal cancer risk 下载免费PDF全文
Carriage of nuclear dehydrogenating clostridia has been associated with colon cancer and implicated in its aetiology. This study has compared the carriage of these organisms in a British population at high risk for the development of colon cancer with a low risk Nigerian population. Clostridia were found in all of the stools from both populations. Nuclear dehydrogenating clostridia were only found in the stools of the British subjects (32%). These results support the suggestion that the carriage rate of nuclear dehydrogenating clostridia in a population is related to the risk of colon cancer. 相似文献
13.
Kathleen Rooney Caroline Hunt Leanne Humphreys David Harding Miriam Mullen John Kearney 《Clinical psychology & psychotherapy》2005,12(2):97-111
Prior reports suggest an ambivalence regarding treatment in individuals with Post-Traumatic Stress Disorder (PTSD). A model that accommodates such ambivalence is the Transtheoretical Model of Behavior Change (TTM, also known as the Stages-of-Change Model). Fifty veterans presenting for treatment completed self-report measures (94% response rate) that assessed disorder variables and constructs relating to the TTM. While the relationships between the components of each specific construct were found to be consistent with the findings of other studies and a number of predicted relationships between variables were confirmed, many results were inconsistent with the TTM. Notwithstanding questions about the suitability of the self-report measures, the unique characteristics of the veteran sample and the small sample size, the results suggest that the assumptions of the TTM were not met in veterans with PTSD. Copyright © 2005 John Wiley & Sons, Ltd. 相似文献
14.
This study sought to obtain empirical data on the issue of whether susceptibility to hypnosis influences the outcome of an hypnotic therapy. At the first of two sessions, Ss had their susceptibility evaluated unobtrusively. At the second session, they learned Spiegel's self-hypnotic method to stop smoking. At the end of 3 months' follow-up 7 of 54 volunteers were completely abstinent (13%), while 31% had reduced smoking by 50% or more. Of the 7 totally abstaining Ss, 1 was high, 1 was low and 5 were medium susceptible, which is not unlike the distribution of hypnotic susceptibility in the general population. However, it was found that significantly more Ss of higher susceptibility reduced by 50% or more than did less susceptible Ss. 相似文献
15.
O'Shea S Chrystie I Cranston R Mullen J Corbett K Murphy G Parry JV De Ruiter A Banatvala J 《Journal of medical virology》2000,61(2):187-194
During routine monitoring of human immunodeficiency virus (HIV) viral load, two problems arose. First, a number of patients, the majority being African, were found to have low viral loads by the Chiron branched-chain DNA assay in conjunction with low CD4(+) cell numbers. In order to determine whether this was due to failure of the branched-chain DNA assay to detect non-B subtypes of HIV, selected samples were subtyped and HIV RNA quantified by branched-chain DNA, NASBA, and the Roche Monitor RT-PCR assay. Twenty-eight (97%) of 29 Africans were infected with a non-B subtype of HIV and 15 (93.7%) of 16 non-Africans with subtype B. Twenty-three samples had a low viral load by branched-chain DNA, which was confirmed by the NASBA and RT-PCR assays. All three assays detected B and non-B subtypes with similar efficiency; NASBA failed to detect HIV RNA in a small number of non-B samples. Discrepancies between viral load and CD4(+) cell numbers did not appear therefore to be related to subtype. Second, while quantification of HIV RNA was being conducted using version 2 of the branched-chain DNA assay (lower detection limit 500 HIV RNA copies/ml) the manufacturers had developed a more sensitive assay and a comparative evaluation was therefore conducted. In approximately 30% of samples the viral load was up to 10 times higher with the more sensitive assay. These experiences emphasise the importance of close collaboration between the clinic and the laboratory. 相似文献
16.
Development of hatching blastocysts from immature human oocytes following in-vitro maturation and fertilization using a co-culture system 总被引:8,自引:0,他引:8
Hwu YM; Lee RK; Chen CP; Su JT; Chen YW; Lin SP 《Human reproduction (Oxford, England)》1998,13(7):1916-1921
Recently, in-vitro maturation (IVM) of immature human oocytes recovered
from non-stimulated follicles has been applied in the treatment of
infertility. However, in previous reports, very few embryos cultured in
conventional medium have reached the expanded blastocyst stage following
in-vitro maturation and fertilization (IVM/IVF). The objective of this
study was to investigate whether the developmental competence of human
embryos following IVM/IVF could be enhanced by the use of a human ampullary
cell co-culture system. Immature human oocytes were aspirated from small
follicles at Caesarean section and then cultured in medium containing human
menopausal gonadotrophin for 36 to 48 h, followed by insemination. Zygotes
were randomly cultured either in conventional culture medium alone or in
the co-culture system. Of 48 embryos cultured in conventional medium alone,
all arrested at the 2-16- cell stage on day 3 after insemination. Of 46
embryos cultured in the co-culture system, 26 embryos (56.5%) arrested at
the 2-16-cell stage. Six embryos (13%) developed to the morula stage.
Fourteen embryos (30.4%) developed to expanded blastocysts and two
blastocysts were hatching on day 7 after insemination. We conclude that
co-culture significantly enhances the development of blastocysts in embryos
resulting from IVM/IVF.
相似文献
17.
Detection of chromosomes and estimation of aneuploidy in human spermatozoa using fluorescence in-situ hybridization 总被引:11,自引:0,他引:11
The development and application of fluorescence in-situ hybridization
(FISH) has opened the way for comprehensive studies on numerical chromosome
abnormalities in human spermatozoa. FISH can be rapidly applied to large
numbers of spermatozoa and thus overcomes the major limitation of
karyotyping spermatozoa after penetration of zona-free hamster oocytes. The
simultaneous hybridization of two or more chromosome-specific probes to
spermatozoa and subsequent detection of the bound probes using different
fluorescent detection systems enables two or more chromosomes to be
localized simultaneously in the same spermatozoon and provides a technique
for undertaking reasonable estimates of aneuploidy. The most commonly used
probes are those which bind to the centromeric region of specific
chromosomes. Most studies to date have concentrated on estimating
aneuploidy in spermatozoa from normospermic men, although reports are
beginning to appear on aneuploidy in spermatozoa from subfertile and
infertile men. Multi- probe FISH studies have generally reported disomy
(hyperhaploidy) estimates of 0.05-0.2% per chromosome. There is preliminary
evidence that some chromosomes such as X, Y and 21 are predisposed towards
higher rates of non-disjunction during spermatogenesis. There are also
suggestions of inter-donor variability in aneuploidy frequencies for
specific chromosomes, although this requires confirmation in larger
studies. While FISH is clearly a powerful technique that has many
applications in reproductive medicine, it must also be realized that it
does have limitations and the technology itself is still evolving and has
yet to be fully validated on spermatozoa.
相似文献
18.
Preliminary observations on polar body extrusion and pronuclear formation in human oocytes using time-lapse video cinematography 总被引:10,自引:17,他引:10
Payne D; Flaherty SP; Barry MF; Matthews CD 《Human reproduction (Oxford, England)》1997,12(3):532-541
In this study, we have used time-lapse video cinematography to study
fertilization in 50 human oocytes that had undergone intracytoplasmic sperm
injection (ICSI). Time-lapse recording commenced shortly after ICSI and
proceeded for 17-20 h. Oocytes were cultured in an environmental chamber
which was maintained under standard culture conditions. Overall, 38 oocytes
(76%) were fertilized normally, and the fertilization rate and embryo
quality were not significantly different from 487 sibling oocytes cultured
in a conventional incubator. Normal fertilization followed a defined course
of events, although the timing of these events varied markedly between
oocytes. In 35 of the 38 fertilized oocytes (92%), there were circular
waves of granulation within the ooplasm which had a periodicity of 20-53
min. The sperm head decondensed during this granulation phase. The second
polar body was then extruded, and this was followed by the central
formation of the male pronucleus. The female pronucleus formed in the
cytoplasm adjacent to the second polar body at the same time as, or
slightly after, the male pronucleus, and was subsequently drawn towards the
male pronucleus until the two abutted. Both pronuclei then increased in
size, the nucleoli moved around within the pronuclei and some nucleoli
coalesced. During pronuclear growth, the organelles contracted from the
cortex towards the centre of the oocyte, leaving a clear cortical zone. The
oocyte decreased in diameter from 112 to 106 microm (P < 0.0001) during
the course of the observation period. The female pronucleus was
significantly smaller in diameter than the male pronucleus (24.1 and 22.4
microm respectively, P = 0.008) and contained fewer nucleoli (4.2 and 7.0
respectively, P < 0.0001). After time-lapse recording, oocytes were
cultured for 48 h prior to embryo transfer or cryopreservation. Embryo
quality was related to fertilization events and periodicity of the
cytoplasmic wave, and it was found that good quality embryos arose from
oocytes that had more uniform timing from injection to pronuclear abuttal
and tended to have a longer cytoplasmic wave. In conclusion, we have shown
that time-lapse video cinematography is an excellent tool for studying
fertilization and early embryo development, and have demonstrated that
human fertilization comprises numerous complex dynamic events.
相似文献
19.
T P Stein G P Buzby M H Gertner W C Hargrove M J Leskiw J L Mullen 《The American journal of physiology》1980,239(4):G280-G287
We studied the effect of parenteral nutrition with amino acids and hypertonic glucose on protein synthesis and liver fat metabolism. Patients with operable gastrointestinal tract malignancies were divided into two groups. Group I ate the hospital diet ad libitum for the 7-10 days preceding surgery. Group II were given adjuvant parenteral nutrition (APN) for 7-10 days prior to the surgical removal of the tumor. Daily nutrient intake and nitrogen balance were determined. [15N[glycine (1-2 g) was infused at a constant rate for 12-18 prior to surgery. During surgery, blood, liver, and muscle specimens were taken for 15N analysis. Fractional protein synthesis rates were estimated by the method of Garlick et al. (Biochem. J. 136: 935-945, 1973). The fat content and distribution pattern in the liver was determined by gas chromatography-mass spectrometry. The following results were found. 1) APN increaed the albumin synthesis rate. 2) The fraction of linoleate in the total liver fatty acids were reduced by 75% in the APN patients. 3) Some of the APN patients developed fatty livers during the study. When the APN patients were subdivided on the basis of whether they had fatty livers, it was found that only those patients who did not accumulate fat showed an improvement in their plasma albumin concentration during the period of parenteral nutrition. 相似文献
20.
Kaliraman V Mullen JR Fricke WM Bastin-Shanower SA Brill SJ 《Genes & development》2001,15(20):2730-2740
The RecQ DNA helicases, human BLM and yeast Sgs1, form a complex with topoisomerase III (Top3) and are thought to act during DNA replication to restart forks that have paused due to DNA damage or topological stress. We have shown previously that yeast cells lacking SGS1 or TOP3 require MMS4 and MUS81 for viability. Here we show that Mms4 and Mus81 form a heterodimeric structure-specific endonuclease that cleaves branched DNA. Both subunits are required for optimal expression, substrate binding, and nuclease activity. Mms4 and Mus81 are conserved proteins related to the Rad1-Rad10 (XPF/ERCC1) endonuclease required for nucleotide excision repair (NER). However, the Mms4-Mus81 endonuclease is 25 times more active on branched duplex DNA and replication fork substrates than simple Y-forms, the preferred substrate for the NER complexes. We also present genetic data that indicate a novel role for Mms4-Mus81 in meiotic recombination. Our results suggest that stalled replication forks are substrates for Mms4-Mus81 cleavage-particularly in the absence of Sgs1 or BLM. Repair of this double-strand break (DSB) by homologous recombination may be responsible for the elevated levels of sister chromatid exchange (SCE) found in BLM(-/-) cells. 相似文献