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1.
F. Dagani D. Curti F. Marzatico 《Molecular and chemical neuropathology / sponsored by the International Society for Neurochemistry and the World Federation of Neurology and research groups on neurochemistry and cerebrospinal fluid》1989,10(3):157-169
The effect of Ca2+-homopantothenate (HOPA) treatment (250 mg/kg for 5 d) has been studied by evaluating the specific activity of enzymes related to: glycolytic pathway (hexokinase, phosphofruc-tokinase, pyrurate kinase, lactate dehydrogenase), tricarboxylic acid cycle (citrate synthase, malate dehydrogenase), mitochondrial electron transfer chain (succinate dehydrogenase, cytochrome oxidase), NADH redox state (NADH cytochromec reductase), acetylcholine metabolism (acetylcholinesterase), and glutamate metabolism (glutamate dehydrogenase). The enzymatic activity assays were performed on homogenatein toto, nonsynaptic mitochondria and synaptosomes isolated from: cerebral cortex, hippocampus, striatum, hypothalamus, medulla oblongata, and cerebellum of normoxic rats and rats submitted to intermittent normobaric hypoxia (90:10, N2:O2). In normoxic rats, HOPA was unable to induce any modification. Hypoxiaper se induced a decrease in the activity of synaptosomal cytochrome oxidase in cerebral cortex, hippocampus, and cerebellum. 相似文献
2.
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
3.
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
4.
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
5.
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
6.
Agglutinins titers against Y. enterocolitica 0:3, 0:5, 0:9 and Y. pseudotuberculosis I were determined by the microagglutination method in 777 blood donor sera.Titers of <- 1/10 were observed in 93.5% of the subjects for Y. enterocolitica 0:3, in 87.8% for Y. enterocolitica 0:9 and in 95.1% for Y. enterocolitica 0:5 and for Y. pseudotuberculosis I. Low level titers (1/10 – 1/20) were found in 11.4% to 23.1%. Titers of 1/40 were observed in 1.7% for Y. enterocolitica 0:3, in 1.4% for Y. enterocolitica 0:5, in 5.1% for Y. enterocolitica 0:9 and in 1.2% for Y. pseudotuberculosis I. Titers of 1/80 were seen in 0.2% for Y. enterocolitica 0:3, in 0.1% for Y. enterocolitica 0:5 and in 1.3% for Y. enterocolitica 0:9. Only in one donor's serum was a titer of 1/160 against Y. enterocolitica 0:9 found.The upper limit of normal titer at 15% cutoff level against Yersinia antigens, found in blood donor sera by the microagglutination test, was 1/10. 相似文献
7.
Sharfman W Urba W Smith J Janik J Curti B Gause B Holmlund J Steis R Beauchamp A Longo D 《International journal of oncology》1995,6(3):579-583
We conducted a phase I/II trial of 5-fluorouracil (5-FU), calcium leucovorin (LV), zidovudine (AZT) and dipyridamole (DP), (FLAP) in patients with metastatic colorectal cancer, renal cell carcinoma and malignant melanoma. AZT and DP were given to enhance the biochemical modulation and antitumor activity of 5-FU and LV. All patients received 5-FU (370 mg/m(2) i.v. bolus day 0-4), LV (50 mg/m(2) p.o. every 4 h day 0-4) and DP (50 mg/m(2) p.o. every 6 h days 0-27). In the phase I portion of the study, AZT was dose escalated in cohorts of 5 patients each, from 50 mg p.o. every 6 h days 0-27 to the MTD of 200 mg p.o. every 6 h days 0-27. Thirty-three patients received 200 mg of AZT in the phase II portion of the trial. Eleven patients developed grade III and 5 patients developed grade IV leukopenia. Four patients developed grade III and 21 patients developed grade IV neutropenia, with six febrile neutropenic episodes. Six patients experienced grade III anemia and four grade III thrombocytopenia. Diarrhea or stomatitis of greater than or equal to grade III occurred in six and four patients, respectively. Fifty-eight percent (19 of 33) of patients required dose reductions of AZT for hematologic toxicity (13 of 19 in the first treatment cycle). At the 200 mg AZT dose level, there were two partial responses in nine colorectal cancer patients (22%), no objective responses in 14 patients with renal cell carcinoma or in 14 patients with melanoma. FLAP does not have significant activity in melanoma, renal cell carcinoma or 5-FU-treated colorectal cancer patients, although it may have activity in untreated colon cancer. 相似文献
8.
Multidisciplinary approach to palliation of obstructive jaundice caused by a central hepatocellular carcinoma 总被引:3,自引:0,他引:3
BACKGROUND/AIMS: Obstructive jaundice due to intraductal tumour growth is a rare symptom in association with hepatocellular carcinoma (HCC). METHODS: We report a 65-year-old white male who was admitted to our department with a 2-week history of progressive jaundice. At laparotomy, the liver showed advanced cirrhosis due to long-standing biliary obstruction. Cholangiography confirmed total obstruction of the main bifurcation of the hepatic duct by intraductal tumour growth. Combination treatment with surgical segment III drainage, transcatheter arterial embolization and radioembolization with yttrium-90 resin particles and endoscopic stenting was performed. This form of treatment has never been reported before. RESULTS: With these combined procedures, relief of jaundice and a survival time of 32 months could be achieved. CONCLUSION: The combination of palliative methods may relieve jaundice, ensure a good quality of life and possibly prolong survival in patients with mechanical tumour obstruction of the biliary tree by HCC. 相似文献
9.
Pathways to care for alcohol use disorders 总被引:1,自引:0,他引:1
10.