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151.
Abstract: Low and high resolution sequence specific oligonucleotide probe hybridization patterns were used to design an approach to direct sequencing of allele specific amplified cDNA. Several PCR amplifications were used to derive overlapping sequence fragments to define complete first domain sequences for a single allele. This method has been used to characterize three new DRB1 alleles in the DR52 family, DRB1*1115, DRB1* 1117, and DRB1*1319. All three alleles carry polymorphisms previously observed in other DRB alleles and underscore the importance of utilizing a directed sequencing approach for obtaining unambiguous typing results in matching for bone marrow transplantation between unrelated donor and recipient. 相似文献
152.
Summary Epstein Barr Virus (EBV) receptor activity in cell free extracts is operationally defined as one which causes a reduction in the effective concentration of the early antigen inducing particles of an EBV preparation when the latter is preincubated with the extract before infection. Such activity was detected in the surface extract of Raji cells and to a lesser extent in that of BJAB cells, both of which are B lymphoblastoid cells that are susceptible to infection with EBV. Receptor activity was not detected in similar extracts of P3HR-1 cells and human diploid fibroblasts neither of which are known to be susceptible to EBV infection.Receptor activity in the Raji cell extract was found to be associated with membranous structures. This may have rendered the activity resistant to treatment with trypsin and sonication. The activity was however abrogated if the extract was exposed to neutral detergent.Binding of receptor activity was observed when Raji cell extract was chromatographed on a column of immobilized EBV. Subsequent electrophoretic analysis showed however that this procedure did not result in an appreciable purification of the receptor activity. Neutral detergent treated extract was similarly chromatographed. The resulting eluates did not contain detectable receptor activity but were less heterogeneous in protein content as compared with that of the original extract. It is not certain at present if these EBV binding proteins are involved in the receptor activity of the extract.With 3 Figures 相似文献
153.
Case report: human herpesvirus 7 associated fatal encephalitis in a peripheral blood stem cell transplant recipient 总被引:2,自引:0,他引:2
Chan PK Chik KW To KF Li CK Shing MM Ng KC Yuen PM Cheng AF 《Journal of medical virology》2002,66(4):493-496
Previous studies have suggested a neuroinvasive and neuropersistent potential of human herpesvirus 7 (HHV-7). In this report, a case of fatal encephalitis is described and its association with HHV-7 infection is discussed. An 8-year-old girl received a peripheral blood stem cell transplant for relapsed acute lymphoblastic leukaemia. The post-transplant period was uneventful and a course of intrathecal chemotherapy was given on Day-30. On Day-41, she developed acute encephalopathy with diplopia and nystagmus. She ran a rapid downhill course and succumbed despite antiviral treatment. The only positive pathological finding was the multiple microscopic foci of haemorrhage associated with neuronal degeneration detected in the brain stem. All microbiological investigations were negative, except for the presence of HHV-7 DNA in cerebrospinal fluid and brain stem tissue samples. 相似文献
154.
Marks GB Ng K Zhou J Toelle BG Xuan W Belousova EG Britton WJ 《The Journal of allergy and clinical immunology》2003,111(3):541-549
BACKGROUND: There are conflicting reports on the effect of BCG vaccination on the subsequent development of atopy and asthma. There are no data on the effects of neonatal BCG vaccination on cytokine responses of lymphocytes that are exposed in vitro to allergens. OBJECTIVES: We sought to test the hypothesis that neonatal BCG vaccination or, alternatively, evidence of an immunologic memory of this vaccination is associated with a reduced prevalence of allergic sensitization, asthma, eczema, and hay fever during childhood. METHODS: An historical cohort study was conducted among 7- to 14-year-old children who were born in 2 districts in Sydney, Australia, and whose mothers were born in southeast Asia. One district had routinely administered BCG vaccination to infants born to overseas-born mothers and the other had not. Eligible subjects were identified from birth registers. Consenting subjects completed questionnaires, performed spirometric and airway hyperresponsiveness testing, and had allergen skin prick testing and tuberculin skin testing. Blood was collected to measure total serum IgE levels and for in vitro lymphocyte culture in the presence of an extract of house dust mite, the dominant allergen in this region, and purified protein derivative of Mycobacterium tuberculosis (tuberculin). IL-4, IL-5, IL-10, and IFN-gamma were measured in the culture supernatant. RESULTS: The cohort included 309 BCG-vaccinated subjects and 442 non-BCG-vaccinated subjects. BCG-vaccinated subjects did not have a lower rate of allergic sensitization than nonvaccinated subjects. However, among the subgroup of subjects with a family history of rhinitis or eczema, BCG vaccination was associated with a lower prevalence of current asthma (defined as recent wheezing plus airway hyperresponsiveness; relative risk, 0.46; 95% CI, 0.22-0.95). BCG vaccination was also associated with lower levels of allergen-stimulated IL-10 production in vitro. Among the BCG-vaccinated subjects, the 44 (14.3%) who had tuberculin skin test reaction sizes of 5 mm or greater and the 31 (18.3%) who demonstrated an in vitro IFN-gamma response to purified protein derivative of M tuberculosis did not have lower rates of allergic sensitization and, overall, did not have a lower prevalence of allergic disease than tuberculin skin test or IFN-gamma nonreactors. CONCLUSION: We conclude that neonatal BCG vaccination has an effect on T-cell allergen responsiveness 7 to 14 years after vaccination and that among a subgroup of subjects with an inherited predisposition to allergic disease, this is associated with clinically relevant beneficial effects. The findings of this study encourage the view that external influences on the immune system in the neonatal period have consequences that extend into later childhood and influence the expression of asthma. Genetic factors are likely to modify the effect of those external factors. 相似文献
155.
The honeybee syndrome - implications of the teratogenicity of mannose in rat-embryo culture 总被引:6,自引:0,他引:6
N Freinkel N J Lewis S Akazawa S I Roth L Gorman 《The New England journal of medicine》1984,310(4):223-230
Lethal effects of D-mannose in the honeybee have been recognized for more than a half a century. We observed another toxic effect of D- mannose during culture of rat embryos from the early head-fold stage to the 26-to-29-somite stage (Days 9-1/2 through 11-1 of gestation). The addition to culture mediums of 1.5 mg of D-mannose per milliliter caused growth retardation and faulty neural-tube closure in approximately two thirds of the embryos. Mannose effects occurred during the first 24 hours of culture and were attended by modes inhibition of the glycolysis that constitutes the principal energy pathway at this stage of development. Adding more glucose to preserve glycolytic flux or increasing atmospheric oxygen to promote oxidative metabolism offset the mannose teratogenesis. Our findings highlight the metabolic vulnerabilities that exist during early organogenesis, before oxidative flexibility is established. They may serve as a model to explain the teratogenicity of many other seemingly unrelated agents that could act by perturbing glycolysis at this vulnerable stage. 相似文献
156.
Collision tumour of the oesophagus: a challenge for histological diagnosis. 总被引:2,自引:0,他引:2 下载免费PDF全文
An unusual case of mantle cell lymphoma metastasising to squamous cell carcinoma of the oesophagus, in a 62 year old Chinese man, is reported. A histological diagnosis based on examination of a small endoscopic biopsy specimen, in the absence of detailed clinical information, may be difficult, as the lymphoma component can be mistaken for reactive lymphoid infiltrate which is sometimes present adjacent to squamous cell carcinoma. Correlation with the clinical history, careful assessment of the subtle histological changes, and use of ancillary methods such as immunohistochemistry are most helpful in making the correct diagnosis. This case also illustrates further the possible occurrence of lymphomatous infiltrates surrounding other lesions in patients with a previous or concurrent history of lymphoma. 相似文献
157.
Timothy A. Jennings MD Ng Bernard MD Ann Boguniewicz MD Muzaffar Khan MD Donald Rice MD James Figge MD 《Endocrine pathology》1998,9(4):353-361
Hemorrhagic adrenal pseudocysts are uncommon nonneoplastic lesions that have been reported as secondary to intraparenchymal
hemorrhage or alternatively related to endothelial (vascular) cysts. Ultrastructural and immunohistochemical evidence in support
of the latter has been presented, but the exact nature of hemorrhagic adrenal pseudocysts remains poorly defined. We evaluated
six surgical specimens of hemorrhagic adrenal pseudocysts using immunohistochemical staining for CD31 and CD34, as well as
conventional histochemistry. All six cases had hemorrhagic contents within a wall of variable thickness possessing focal areas
of linear, disrupted elastin, and smooth muscle. Three cases demonstrated extensive thrombosis with organization, including
papillary endothelial hyperplasia, simulating angiosarcoma. In these cases, CD31 and CD34 staining decorated areas of papillary
endothelial hyperplasia as well as foci of the internal cyst lining, whereas the other cases were negative for both antibodies.
Of interest is the history of FNA prior to surgical resection in three cases of hemorrhagic adrenal pseudocysts, two of which
showed papillary endothelial hyperplasia. The presence of papillary endothelial hyperplasia and our immunohistochemical findings
support, the conclusion that adrenal pseudocysts are posthemorrhagic and derive from vascular disruption. Furthermore, FNA
or other interventional studies may be associated with papillary endothelial hyperplasia in hemorrhagic adrenal pseudocysts. 相似文献
158.
Y chromosome microdeletions, in azoospermic or near-azoospermic subjects, are located in the AZFc (DAZ) subregion 总被引:9,自引:2,他引:9
Submicroscopic deletions of the Y chromosome and polymorphisms of the
androgen receptor (AR) gene in the X chromosome have been observed in men
with defective spermatogenesis. To further define the subregions/genes in
the Y chromosome causing male infertility and its relationship to
polymorphisms of the AR polyglutamine tract, we screened the genomic DNA of
202 subfertile males and 101 healthy fertile controls of predominantly
Chinese ethnic origin. Y microdeletions were examined with 16
sequence-tagged site (STS) probes, including the RBM and DAZ genes,
spanning the AZFb and AZFc subregions of Yq11, and related to the size of
trinucleotide repeat encoding the AR polyglutamine tract. Y microdeletions
were detected and confirmed in three out of 44 (6.8%) of azoospermic and
three out of 86 (3.5%) severely oligozoospermic patients. No deletions were
detected in any of the patients with sperm counts of >0.5 x 10(6)/ml,
nor in any of the 101 fertile controls. All six affected patients had
almost contiguous Y microdeletions spanning the entire AZFc region
including the DAZ gene. The AZFb region, containing the RBM1 gene, was
intact in five of the six subjects. Y deletions were not found in those
with long AR polyglutamine tracts. Our study, the first in a Chinese
population, suggest a cause and effect relationship between Y
microdeletions in the AZFc region (possibly DAZ), and azoospermia or
near-azoospermia. Y microdeletions and long AR polyglutamine tracts appear
to be independent contributors to male infertility.
相似文献
159.
Summary [2 m+ and [2m°] yeast were transformed to stable leucine prototrophy with the hybrid yeast — E. coli plasmid, pJDB219. This plasmid contains the entire sequence of the endogenous 2 m yeast DNA plasmid in addition to the yeast nuclear LEU2
+ gene and the Co1E1 derivative, pMB9. In the [2 m+] transformants, a new wholly yeast LEU2
+ plasmid, pYX, was generated, probably by a recombination event between pJDB219 and 2 m DNA. The plamid, pYX, in the absence of 2 m DNA, was found to exist in equimolar amounts of two forms, A and B, which probably arise by intramolecular recombination across the inverted repeat sequences of the 2 m DNA portion of the plasmid. pJDB219 was found to require the presence of 2 m DNA to undergo this intramolecular recombination. The results suggest that 2, m DNA and pYX code for a gene product required in this recombination event which pJDB219 cannot produce. 相似文献
160.
Partial trisomy 6p and partial monosomy 9p from a de novo translocation 46, XY, -9, + DER(9)T(6:9)(p211:p24) 总被引:1,自引:0,他引:1
Melanie S. Eden James W. Thelin Karen Michalski Joyce A. Mitchell 《Clinical genetics》1985,28(5):375-384
This report describes an adult male with a partial trisomy 6p(p211-pter) and a partial monosomy 9p(9p24-pter) resulting from a de novo unbalanced translocation. This patient does not show the classical featured of the 9p partial monosomy syndrome, thus disputing the claim of Hoo et al. (1982) that 9p24 is the critical segment for the monosomy syndrome. Partial trisomy for 6p has only been previously reported in children. In addition to the chromosomal anomalies, the patient has autosomal recessive spinal muscular atrophy with a different age of onset than two affected sibs. Finally, he shows unusual audiologic and ophthalmologic signs nor previously reported as part of the 9p monosomy or 6p trisomy syndromes. 相似文献