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81.
Obstruction of the small intestine: accuracy and role of CT in diagnosis 总被引:17,自引:0,他引:17
Maglinte DD; Gage SN; Harmon BH; Kelvin FM; Hage JP; Chua GT; Ng AC; Graffis RF; Chernish SM 《Radiology》1993,188(1):61
82.
The acrosome reaction is an important marker for human sperm function.
Since different laboratory techniques may be used for the detection of this
exocytotic process, the purpose of the present study was to compare three
common markers [Pisum sativum agglutinin (PSA), concanavalin A (ConA),
double staining] and transmission electron microscopy for identification of
acrosomal changes. Preliminary findings had demonstrated that similar
results were achieved with Trypan Blue and Hoechst 33258 staining.
Therefore, supravital stainings were omitted. In various experiments, human
spermatozoa were treated with two concentrations (10 and 3.3 microM) of
calcium ionophore A23187 for 15, 30 and 60 min after capacitation for 3 and
6 h at 37 degrees C. The percentages of spermatozoa with acrosomal loss
detected by fluorescein isothiocyanate (FITC)-ConA were consistently lower
than those obtained by double staining or FITC-PSA, which showed comparable
results. Following 6 h of capacitation and incubation with 10 microM
ionophore for 1 h at 37 degrees C, 25.9 +/- 15.7% of all spermatozoa showed
almost complete loss of the acrosomal content. Binding of FITC- ConA to the
acrosomal region was observed in 27.0 +/- 13.2% of spermatozoa obtained
from the same sample. FITC-ConA and double staining or FITC-PSA detect
different stages of the acrosome reaction and may be helpful for a
differentiated evaluation of this sperm function.
相似文献
83.
84.
Manneschi L ° Battisti C Pesci I° Malandrini A° Santorelli FM Scaglioni A° Federico A Montanari E° . 《Journal of the peripheral nervous system : JPNS》2004,9(2):123-123
Charcot‐Marie‐Tooth disease constitutes a clinically and genetically heterogeneous group of hereditary motor and sensory peripheral neuropathies. On the basis of electrophysiologic properties and histopathology, CMT has been divided into demyelinating (type 1) and axonal (type 2) neuropathies. The form of Charcot‐Marie‐Tooth neuropathy that maps to Xq13 may present mild electrophysiological changes (NCV > 40 M/s), mixed neuropathy (NCV: Intermediate (30–40 M/s), or demyelinating neuropathy (NCV: Slow (<37 M/s). On molecular grounds, CMTX is caused by mutations in GJB1 gene, coding for Connexin 32 protein. A 42‐year‐old man, with no other affected family members, was clinically evaluated for CMT. Three years ago he noticed thumb abductor atrophy and then leg muscle atrophy. He presented with hand and leg muscle atrophy, bilateral pes cavus, areflexia, and apallesthesia. The median and ulnar motor NVC were 35–38 m/s, and the median sensory NVC was 35 m/s. Both motor and sensory nerve action potentials were markedly reduced. After exclusion of CMT1A and 1B, analysis for CMTX was performed. The mutation screening of GJB1 gene showed a 9bp insertion upstream the 194ATG codon (Met194) with preservation of the downstream sequence. The three new amino acids (Thr‐Val‐Phe) inserted are localized between the end of the second extracellular domain and the beginning of the fourth transmembrane domain. This is the first 9bp insertion found in GJB1 gene; a genotype‐phenotype correlation may be deduced. 相似文献
85.
Cutaneous leiomyosarcoma typically presents as solitary, well‐circumscribed, firm plaques or nodules. We describe a case of cutaneous leiomyosarcoma clinically presenting as a skin tag on the thigh of a 50‐year‐old male. Histological examination of the lesion revealed a dome‐shaped tumor with interlacing fascicles of smooth muscle with pleomorphism, cellular atypia and multiple mitoses. Malignant tumors may rarely present as a skin tag, and these are most frequently basal cell carcinomas. We are unaware of previously reported leiomyosarcoma clinically presenting as a skin tag. This case suggests that solitary, wide‐based, papilloma‐like lesions or skin tags should be submitted for histologic examination to rule out malignancy. 相似文献
86.
Eva Clemens Andrica CH de Vries Antoinette am Zehnhoff-Dinnesen Wim JE Tissing Jacqueline J Loonen Saskia FM Pluijm 《Pediatric hematology and oncology》2017,34(2):120-129
Cisplatin and carboplatin are effective antineoplastic agents. They are also considered to be potentially highly ototoxic. To date, no long-term follow-up data from well-documented cohorts with substantial numbers of childhood cancer survivors (CCS) with platinum-related hearing loss are available. Therefore, in this study, we studied the reversibility of ototoxicity from discontinuation of treatment onwards in a national cohort of platinum-treated survivors with hearing loss at the end of cancer treatment. Of the 168 CCS with follow-up audiograms, we longitudinally evaluated the course of hearing function in 61 CCS who showed hearing impairment at discontinuation of treatment according to the Münster criteria (>20 dB at ≥4–8 kHz). Survivors were treated with platinum (median total cumulative dose cisplatin: 480 mg/m2 and median total cumulative dose carboplatin: 2520 mg/m2). Median follow-up time was 5.5 years (range: 1.0–28.8 years). The results showed that none of these survivors revealed improvement of hearing function even till 28.8 years after discontinuation of treatment (grade <2b during long-term follow-up). An increase in hearing loss with two or three Münster degrees was observed in five of 61 survivors after 1.6–19.6 years. Overall, this indicates that ototoxicity after platinum treatment may be irreversible and that longitudinal clinical audiological monitoring and care is required in long-term survivors of childhood cancer on a large scale. 相似文献
87.
88.
Elisabeth APM Romme John T Murchison Kee F Phang Frits H Jansen Erica PA Rutten Emiel FM Wouters Frank WJM Smeenk Edwin JR Van Beek William MacNee 《Journal of bone and mineral research》2012,27(11):2338-2343
Chronic obstructive pulmonary disease (COPD), although primarily a disease of the lungs, is associated with extrapulmonary effects such as muscle weakness and osteoporosis. Fractures owing to osteoporosis cause significant morbidity and mortality, particularly in patients with COPD. To prevent osteoporotic fractures, it is important to diagnose osteoporosis in an early stage and to start anti‐osteoporotic therapy in at‐risk patients. Because routine chest computed tomography (CT) is increasingly used to assess the extent of emphysema and airways disease in patients with COPD, we investigated whether simple attenuation measurement of the thoracic spine on routine chest CT may provide useful information on bone health in patients with COPD. Fifty‐eight patients with moderate to very severe COPD were included in our study. The average attenuation of thoracic vertebrae 4, 7, and 10 on chest CT was correlated with the lowest bone mineral density (BMD) of the hip and lumbar spine (L1 to L4) on dual‐energy X‐ray absorptiometry (DXA) in patients with COPD. The inter‐ and intra‐observer variabilities of the attenuation measurements were low as shown by Bland‐Altman plots. Pearson's correlation coefficient between the average attenuation of the three thoracic vertebrae and the lowest BMD of the hip and lumbar spine was high (r = 0.827, p < 0.001). A receiver‐operating characteristic (ROC) analysis of the area under the curve for osteoporosis was 0.969 (p < 0.001), corresponding to an attenuation threshold of 147 Hounsfield Units (HU). In conclusion, our data demonstrated that bone attenuation measured on routine chest CT correlated strongly with BMD assessed on DXA in patients with COPD. Routine chest CT may provide useful information on bone health in patients with COPD. © 2012 American Society for Bone and Mineral Research. 相似文献
89.
Richards AJ; Yates JR; Williams R; Payne SJ; Pope FM; Scott JD; Snead MP 《Human molecular genetics》1996,5(9):1339-1343
Stickler syndrome (hereditary arthro-ophthalmopathy) is the commonest
inherited cause of retinal detachment and one of the commonest autosomal
dominant connective tissue dysplasias. There is clinical and locus
heterogeneity with about two thirds of families linked to the gene encoding
type II procollagen (COL2A1). Families with Sticklers syndrome type 1 have
a characteristic congenital vitreous anomaly and are linked without
recombination to markers at the COL2A1 locus. In contrast families with the
type 2 variety have a different vitreo- retinal phenotype and are not
linked to the COL2A1 gene. Type XI collagen is a quantitatively minor
fibrillar collagen related to type V collagen and associated with the more
abundant type II collagen fibrils. A mutation in COL11A2, the gene for
alpha 2 (XI) procollagen, has recently been found in a family described as
having Stickler syndrome, although there was no ocular involvement. Here we
show for the first time that a family with the full Type 2 Stickler
syndrome including vitreous and retinal abnormalities is linked to the
COL11A1 gene and characterise the mutation as a Glycine to Valine
substitution at position 97 of the triple helical domain caused by a single
base G-- >T mutation. These results are the first to provide
confirmation that type XI collagen is an important structural component of
human vitreous. They also support previous work suggesting that mutations
in the genes encoding collagen XI can give rise to some manifestations of
Stickler syndrome, but of these, only mutations in COL11A1 will give the
full syndrome including the vitreo-retinal features.
相似文献
90.