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991.
Combination of minocycline and rifampicin against methicillin- and gentamicin-resistant Staphylococcus aureus 总被引:4,自引:0,他引:4
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E Yourassowsky MP Van Der Linden MJ Lismont F Crokaert 《Journal of clinical pathology》1981,34(5):559-563
Methicillin- and gentamicin-resistant Staphylococcus aureus may remain sensitive to minocycline and to rifampicin. A study of growth curves has shown that at inhibitory concentrations (0·4 μg/ml), minocycline prevents the development of mutants resistant to rifampicin. 相似文献
992.
Human granulosa cells were maintained in culture with extracellular matrix
in the presence or absence of human chorionic gonadotrophin (HCG) using a
defined culture medium. Such cultures are maintained by gonadotrophin in a
manner suggesting that features of 'luteal rescue' may be occurring in
vitro. Western analysis of culture medium demonstrated that the granulosa
cells produced tissue inhibitor of metalloproteinases (TIMP)-1 but not
TIMP-2. The presence of TIMP-1 in cultured cells was also detected
immunocytochemically. Immunoassay of TIMP-1 output revealed that HCG
exposure for 7 days caused a 2-fold increase in TIMP-1 production versus
control reaching maximum at approximately 1 ng HCG/ml. The sensitivity of
this response to HCG was similar to that observed for stimulation of
progesterone production. Delayed addition of HCG, from day 4 of culture,
elicited increases in TIMP-1 which were evident within 24 hours, and were
not explained by changes in cell replication or survival. Removal of HCG
from cultures previously luteinized with HCG for 6 days resulted in a fall
in TIMP-1 production. Thus TIMP-1 production by luteinized granulosa cells
in culture is gonadotrophin dependent. We speculate that prolonged cellular
function associated with 'luteal rescue' may result from increased
extracellular matrix stability mediated by up-regulation of TIMP-1
production.
相似文献
993.
Starvation Selection Restores Elastase and Rhamnolipid Production in a Pseudomonas aeruginosa Quorum-Sensing Mutant 总被引:5,自引:0,他引:5
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Christian Van Delden Everett C. Pesci James P. Pearson Barbara H. Iglewski 《Infection and immunity》1998,66(9):4499-4502
The las quorum-sensing system of Pseudomonas aeruginosa controls the expression of elastase and rhamnolipid. We report that starvation can select a mutant producing these virulence factors in spite of a lasR deletion. Expression of the autoinducer synthase gene rhlI was increased in this suppressor mutant, suggesting compensation by the rhl system. These data show that P. aeruginosa can restore elastase and rhamnolipid production in the absence of a functional las quorum-sensing system. 相似文献
994.
995.
Adrian?F?Low Christopher?J?O'Donnell Sekar?Kathiresan Brendan?Everett Claudia?U?Chae Stanley?Y?Shaw Patrick?T?Ellinor Calum?A?MacRaeEmail author 《BMC medical genetics》2005,6(1):38
Background
Vascular disease is a feature of aging, and coronary vascular events are a major source of morbidity and mortality in rare premature aging syndromes. One such syndrome is caused by mutations in the lamin A/C (LMNA) gene, which also has been implicated in familial insulin resistance. A second gene related to premature aging in man and in murine models is the KLOTHO gene, a hypomorphic variant of which (KL-VS) is significantly more common in the first-degree relatives of patients with premature coronary artery disease (CAD). We evaluated whether common variants at the LMNA or KLOTHO genes are associated with rigorously defined premature CAD. 相似文献996.
Clinical and histological associations of cagA and vacA genotypes in Helicobacter pylori gastritis. 总被引:10,自引:2,他引:10
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V J Warburton S Everett N P Mapstone A T Axon P Hawkey M F Dixon 《Journal of clinical pathology》1998,51(1):55-61
AIMS: To determine the relation among the cytotoxin associated gene (cagA) and vacuolating cytotoxin gene (vacA) status of Helicobacter pylori isolates, the associated clinical diseases, and the severity and pattern of chronic gastritis. METHODS: Helicobacter pylori was cultured from gastric biopsies obtained from dyspeptic patients. DNA was extracted from the isolates and the cagA and vacA status determined by the polymerase chain reaction (PCR). The prevalence of the different cagA and vacA genotypes in three clinical groups, duodenal ulcer, gastric ulcer, and non-ulcer dyspepsia was compared. The histological features in sections from two antral and two corpus biopsies were graded by one blinded observer. The grades were compared with age and sex matched groups with different cagA and vacA genotypes, and with duodenal ulcers, or non-ulcer dyspepsia. RESULTS: Isolates from 161 patients were included. One hundred and nine (68%) harboured a cagA+ strain and 143 (89%) harboured a vacA s1 strain. The prevalence of cagA+ strains in duodenal ulcer patients (94%) was highly significantly greater than in those with non-ulcer dyspepsia (56%). However, of the patients infected with a cagA+ strain, almost equal numbers had non-ulcer dyspepsia or peptic ulceration. Chronic inflammation, polymorph activity, surface epithelial degeneration, atrophy, and intestinal metaplasia were all significantly more severe in the cagA+ than in the cagA- group, whereas only corpus epithelial degeneration was significantly more severe in the vacA s1 group compared with the vacA s2 group. Patients infected with cagA+ strains were almost four times more likely to have antral intestinal metaplasia than cagA- patients. An antral predominant gastritis was present in duodenal ulcer patients compared with matched non-ulcer dyspepsia patients, but this was not attributable to cagA or vacA status. CONCLUSIONS: Helicobacter pylori strains showing cagA positively and the vacA s1 genotype are associated with more severe gastritis but these virulence factors do not appear to determine the overall pattern. The pattern is closely linked to clinical disease. Therefore, it is likely that the nature of the disease complicating chronic infection is determined by host and environmental factors, while bacterial factors determine the magnitude of the risk of developing such disease. 相似文献
997.
Summary The myosin isozyme composition of the lateral gastrocnemius muscle of the chicken leg was investigated during various stages of development utilizing non-denaturing pyrophosphate gel electrophoresis, two-dimensional gel electrophoresis and peptide mapping techniques. An unusual isoform pattern for fast myosin in the lateral gastrocnemius muscle of the adult chicken leg was demonstrated which consisted of a predominance of myosin homodimers and lesser amounts of myosin heterodimer. In addition, a different myosin heavy chain isoform was present in the adult chicken lateral gastrocnemius muscle when compared to other adult fast-twitch muscles. While the adult lateral gastrocnemius muscle contained a different myosin heavy chain isoform from other adult fast-twitch muscles, the embryonic lateral gastrocnemius muscle contained a myosin heavy chain identical to that of the embryonic pectoralis major. 相似文献
998.
Summary Myosin expression during hypertrophy of the chicken anterior latissimus dorsi (ALD) muscle was investigated by immunocytochemical procedures using monoclonal antibodies to the fast and slow isoforms of the myosin heavy chain (myosin HC). Antifast antibody 1F9 bound to the adult fast HC of pectoralis muscle and cross-reacted with the HC found in early developing muscle. Antislow antibody 3D1 bound exclusively to the HC of slow myosin 2 (SM2). Stretch hypertrophy of the ALD was produced by attaching a weight to the wing; there was no evidence for a change in fibre number in the muscle. Between 4 and 6 days of stretch there appeared a dramatic increase in the number of fibres staining with the antifast antibody which reached a peak between 12 and 19 days. By this time between 28 and 52% of the fibres in the stretched ALD stained to varying degrees with the antifast antibody compared with 1% in the unstretched control ALD. Most antifast-stained fibres in the stretched muscle also stained with the antislow antibody; the contralateral control muscle showed mostly antislow staining except for the very small number of strongly antifast-stained fibres. By 50 days in some birds and by 80 days in all birds antifast staining had returned to normal. Analysis of the isomyosin composition of the ALD by native gel electrophoresis did not reveal a significant increase in fast myosin content of the hypertrophied muscle even though immunocytochemical staining may have suggested otherwise. 相似文献
999.
The maximum thickness of the patella was prospectively measured during 216 primary total knee arthroplasties (TKA) that included patellar resurfacing. Of the measured patellae, 93 were in 75 men and 123 were in 99 women. Average patient age was 68.9 years for men and 71.2 years for women. All patients were diagnosed with osteoarthritis. Mean maximal patellar thickness in men was 26.1 mm and in women it was 22.6 mm. This difference was significant (P < 0.0001). It is recommended that preoperative patellar thickness be restored following patellar resurfacing. The values for patellar thickness in men and women with osteoarthritis which we have noted may serve as a guide to patellar thickness restoration in cases of patellar dysplasia and in revision TKA where preoperative patellar thickness may be unknown. 相似文献
1000.
Denoyelle F; Weil D; Maw MA; Wilcox SA; Lench NJ; Allen-Powell DR; Osborn AH; Dahl HH; Middleton A; Houseman MJ; Dode C; Marlin S; Boulila-ElGaied A; Grati M; Ayadi H; BenArab S; Bitoun P; Lina-Granade G; Godet J; Mustapha M; Loiselet J; El-Zir E; Aubois A; Joannard A; Petit C 《Human molecular genetics》1997,6(12):2173-2177
Prelingual non-syndromic (isolated) deafness is the most frequent
hereditary sensory defect. In >80% of the cases, the mode of
transmission is autosomal recessive. To date, 14 loci have been identified
for the recessive forms (DFNB loci). For two of them, DFNB1 and DFNB2, the
genes responsible have been characterized; they encode connexin 26 and
myosin VIIA, respectively. In order to evaluate the extent to which the
connexin 26 gene (Cx26) contributes to prelingual deafness, we searched for
mutations in this gene in 65 affected Caucasian families originating from
various countries, mainly tunisia, France, New Zealand and the UK. Six of
these families are consanguineous, and deafness was shown to be linked to
the DFNB1 locus, 10 are small non consanguineous families in which the
segregation of the trait has been found to be compatible with the
involvement of DFNB1, and in the remaining 49 families no linkage analysis
has been performed. A total of 62 mutant alleles in 39 families were
identified. Therefore, mutations in Cx26 represent a major cause of
recessively inherited prelingual deafness since according to the present
results they would underlie approximately half of the cases. In addition,
one specific mutation, 30delG, accounts for the majority (approximately
70%) of the Cx26 mutant alleles. It is therefore one of the most frequent
disease mutations so far identified. Several lines of evidence indicate
that the high prevalence of the 30delG mutation arises from a mutation hot
spot rather than from a founder effect. Genetic counseling for prelingual
deafness has been so far considerably impaired by the difficulty in
distinguishing genetic and non genetic deafness in families presenting with
a single deaf child. Based on the results presented here, the development
of a simple molecular test could be designed which should be of
considerable help.
相似文献