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J A Dietl H P Horny F Buchholz 《International journal of gynaecology and obstetrics》1991,34(2):179-182
In the present study the immunohistology of the cellular stromal reaction of invasive squamous cell carcinoma of the cervix is investigated. Tumor tissue from 10 patients with invasive squamous cell carcinoma of the uterine cervix (stages Ib-IIb, according to FIGO) was immunostained by the alkaline phosphatase-anti-alkaline phosphatase (APAAP) method. The monoclonal antibodies OKT3, OKT4, OKT8, TO15, Ki-M1, and Ki-M6 were applied. The cells in the stroma and the tumor foci were evaluated separately. In all cases, the overwhelming majority of lymphoreticular cells were found in the stroma and the tumor-cell complexes contained relatively low numbers of these cells. While B-lymphocytes were present only in low numbers or were virtually absent from the lymphoreticular infiltrates, cells of the mononuclear-phagocyte system were found to be another prominent constituent of the tumor's cellular stromal reaction. 相似文献
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Sodium nitroprusside potentiates the depressor response to the phosphodiesterase inhibitor zaprinast in rats 总被引:2,自引:0,他引:2
R L Dundore P F Pratt W D Hallenbeck M L Wassey P J Silver R A Buchholz 《European journal of pharmacology》1990,185(1):91-97
To determine if the presence of an activator of guanylate cyclase alters the depressor response to a selective inhibitor of low Km cyclic GMP (cGMP) phosphodiesterase (PDE), zaprinast (3-30 mg/kg) was given i.v. to conscious, spontaneously hypertensive rats during a steady state of i.v. infusion of sodium nitroprusside (15 micrograms/kg per min). Sodium nitroprusside significantly increased the magnitude of the depressor response to zaprinast. In contrast, fenoldopam (20 micrograms/kg per min), an activator of adenylate cyclase, did not affect the depressor response to zaprinast. Zaprinast (10 mg/kg) significantly decreased mean arterial pressure (MAP) in rats given an infusion of sodium nitroprusside, an activator of soluble guanylate cyclase, at doses of 15 and 25 micrograms/kg per min but not at a dose of 5 micrograms/kg per min. However, in rats given atrial natriuretic peptide (ANP; 0.5, 1 and 2 micrograms/kg per min), an activator of particulate guanylate cyclase, zaprinast (10 mg/kg) did not affect MAP. In contrast to the potentiation of the depressor response to zaprinast, sodium nitroprusside (15 micrograms/kg per min) significantly attenuated the reductions in MAP produced by CI-930, a selective inhibitor of low Km cAMP PDE. It is concluded that sodium nitroprusside, but not ANP or fenoldopam, potentiates the depressor response to zaprinast. Furthermore, the potentiation of the depressor response to zaprinast is dependent upon the dose of sodium nitroprusside and is selective for zaprinast; the depressor response to CI-930 is attenuated by sodium nitroprusside. 相似文献
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In Germany about 1 million people are chronically infected with the hepatitis B or C virus and most of them are in the reproductive age. If a child is desired, liver function and moreover sexual and materno-fetal risk of transmission should be taken into consideration. Active vaccination can prevent sexual transmission of HBV and simultaneous passive vaccination strategies are able to inhibit consecutive infection of the newborn. Perinatal aquired chronic hepatitis B is typically asymptomatic and shows good short term prognosis. In men with chronic HBV infection transmission of the virus to the fetus by the infected sperm cannot fully be excluded. In HCV infection no successful vaccination strategies are available yet and preventing sexual transmission is based on condom use. Assisted reproduction techniques can reduce the risk of male to female transmission. HCV transmission to the newborn depends on maternal viral load. Perinatal aquired chronic hepatitis C shows a good prognosis. Prior to assisted reproduction antiviral treatment should be considered. 相似文献
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Neurofibromatosis 2 (NF2) is an inherited cancer syndrome resulting from
mutations in the NF2 tumor suppressor gene. Analysis of NF2 mutations has
revealed some general genotype-phenotype correlations. Severe disease has
been associated with mutations that produce a premature termination while
more mild disease has been associated with missense mutations. Here, we
provide experimental proof for these genotype-phenotype correlations by
demonstrating that nonsense mutations fail to produce stable merlin protein
while missense mutations result in the generation of merlin proteins
defective in negative growth regulation. This inability to suppress cell
growth may result from defects in the function of merlin at several levels,
including failure to form an intramolecular complex. Based on these
findings, we propose a model for merlin growth suppression that provides a
framework for analyzing NF2 patient mutations and merlin function.
相似文献
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Kidney transplantation from anencephalic donors 总被引:2,自引:0,他引:2
W Holzgreve F K Beller B Buchholz M Hansmann K K?hler 《The New England journal of medicine》1987,316(17):1069-1070
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Mark A Lovell J David Robertson Bruce A Buchholz Chengsong Xie William R Markesbery 《Neurobiology of aging》2002,23(2):179-186
The time course of formation of neurofibrillary tangles (NFT) and senile plaques (SP) in Alzheimer's disease (AD) brain is unknown. Above ground nuclear weapons testing in the late 1950s and early 1960s led to significantly increased levels of 14C in the atmosphere and carbon cycle. Because the amyloid beta peptide of SP and paired helical filaments of NFT, once formed, are relatively resistant to degradation, 14C levels observed in SP and NFT should reflect their year of formation. The purpose of this study was to develop a method to determine whether 14C levels could be used to define NFT and SP ages. Using accelerator mass spectrometry to measure bomb-pulse 14C levels, we determined the average age of formation of isolated SP and NFT fractions in bulk brain samples of 6 AD subjects. Although preliminary, the results demonstrate that it is possible to use bomb pulse 14C to determine the average year of formation of NFT and SP in the brain in AD. In addition, the data show that these structures, once formed, have a much slower carbon turnover rate than normal brain and are not in a formation/enzymatic degradation equilibrium. 相似文献
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