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81.
Hardy  DC; Murphy  WA; Siegel  BA; Reid  IR; Whyte  MP 《Radiology》1989,171(2):403-414
The radiologic studies of 38 essentially untreated adults with X-linked hypophosphatemia (XLH) were reviewed to determine the prevalence of radiologic features, to compare the findings in men and in women, and to elucidate the natural history of the disease by comparing the findings in young, intermediate-age, and older patients. Bone-reinforcement lines were common, but no characteristic mineral mass alteration was established. Looser zones were more prevalent in older subjects. Osteoarthritis was common, occurring in the ankles, knees, feet, sacroiliac joints, and wrists. Enthesopathy was infrequent in the younger group but was present in every member of the intermediate and older groups and was often accompanied by extra ossicles. Curvatures of the lower-extremity long bones were common in all age groups. Three new skeletal alterations in XLH were found to be common: flaring of the iliac wings, trapezoidal distal femoral condyles, and alterations in talar morphology, including shortening of the talar neck and flattening of the talar dome. Technetium-99m methylene diphosphonate scintigrams of 17 subjects were often abnormal, depicting bowing deformity and focal tracer accumulation in diaphyseal cortices and in periarticular and extraarticular regions. The mean metabolic index was moderately elevated (4.0). Both radiographic and scintigraphic findings were more severe in men, consistent with hemizygosity. The natural history of untreated XLH in both sexes is characterized by the development of a variety of age-related skeletal abnormalities during adulthood.  相似文献   
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84.
The aim of this study is to investigate whether three mononucleotide polymorphisms at the locus -1082,-819 and -592 in the promoter region of the IL-10 gene are associated with chronic severe hepatitis. The IL-10-592 and IL-10-1082 polymorphisms were genotyped by polymerase chain reactionrestriction fragment length polymorphism analysis (PCR-RFLP) while polymerase chain reaction-sequence specific primer (PCR-SSP) assay was used to test the IL-10-819 polymorphism. The polymorphisms of IL-10-1082, -819 and -592 genes were detected in 98 patients with chronic severe hepatitis (CSH), 478 patients with chronic hepatitis B (CHB), 223 asymptomatic (chronic) HBV carriers (ASC) and 267 patients with self-restricted HBV. There was significant difference of the polymorphisms of IL-10-1082, IL-10-819 and IL-10-592 genes between CSH group and other groups. The frequency of AA genotype at IL-10 gene promoter -1082 locus in chronic severe hepatitis patients was higher than that in asymptomatic HBV carriers (2 = 13. 314, P = 0.001), and self-restricted HBV patients (χ^2 = 13.545, P = 0.000); the frequency of CC and AC genotype at IL-10 gene promoter -592 locus in chronic severe hepatitis patients was higher than that in chronic hepatitis patients(χ^2 = 15.970, P=0.000) (χ^2 =20.414, P=0.000), asymptomatic HBV carriers (χ^2 =21.283, P= 0.000) (χ^2 = 28.309, P = 0.000) and self-restricted HBV patients(χ^2 = 17.047, P = 0.000) (χ^2 = 16.528, P = 0.000) ; the frequency of TC genotype at IL-10 gene promoter -819 locus in chronic severe hepatitis patients was higher than that in chronic hepatitis patients(χ^2 = 58.961, P = 0.000), asymptomatic HBV carriers ( χ^2 = 53. 255, P = 0. 001 ) and self-restricted HBV patients (χ^2 = 39.616, P = 0.001). So interleukine-10 gene polymorphism was associated with the chronic severe hepatitis.  相似文献   
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86.
Intestinal neuronal dysplasia and its morphometric evidences   总被引:2,自引:0,他引:2  
The aim of this study was to morphometrically objectify the characteristics of intestinal neuronal dysplasia (IND) B by optic electronic image analysis. Biopsies of 60 children divided into two age groups (8 ± 4 months and 4 years ± 20 months) were examined. Three groups (n = 20) were studied: (1) isolated IND B; (2) Hirschsprung-associated IND B (NAIND), and (3) normal controls. A histotopochemical lactic dehydrogenase (LDH) reaction was used for the morphometric measurement of ganglion size, nerve cell size, and number of nerve cells per ganglion. The submucous neural density was measured with an acetylcholinesterase reaction. The results showed no significant morphometric differences between isolated IND and HAIND. Aging caused an increase in ganglion and nerve cell size. The density of the submucous plexus decreased with age. All parameters measured were significantly different from normal controls. Giant ganglia with a high number of LDH-positive nerve cells (IND: > 7, controls: 4 ± 1 nerve cells/ganglion) were the most relevant diagnostic parameter of IND. The pathogenesis of a dysganglionosis is dominated by abnormal early, genetically caused laminin expression during embryonic life, blocking neuroblast migration (aganglionosis) and prematurely differentiating neuroblasts into myenteric (hypoganglionosis) and submucous plexus (IND). IND B, hypoganglionosis, and aganglionosis are different manifestations of an identical developmental abnormality in which IND is the weakest form.  相似文献   
87.
Breast specimen radiography: evaluation of a compression device   总被引:1,自引:0,他引:1  
Chilcote  WA; Davis  GA; Suchy  P; Paushter  DM 《Radiology》1988,168(2):425-427
The irregular shape and uneven tissue thickness of excised breast specimens makes radiographic evaluation difficult, especially when calcifications are not present. Xeroradiographs before and after compression of 20 separate excised breast specimens were compared, and 17 of the same specimens were compared after compression combined with immersion in water. Specimen compression improved visibility of the lesion on average in 88% of cases, and visibility was equal in 12%. Combined compression/immersion further improved visibility of the lesion on average in 37% of cases. More significantly, evaluation of the compressed specimen led to a change in interpretation of the radiographs in 45% of cases. Compression of the specimen in specimen radiography is recommended in all cases in which pre-biopsy localization is performed.  相似文献   
88.
Between January 1985 and June 1992, the Paediatric Department of Hospital Universiti Sains Malaysia has diagnosed congenital dyserythropoietic anaemia in three children, two of whom were siblings. The age of onset ranged from 1 to 3 years. All of them became transfusion-dependent before the age of 4 months. One of them was successfully treated with bone marrow transplantation.  相似文献   
89.
Pressure, or compressive, erosions of bone in various locations in patients with rheumatoid arthritis are described. Possible pathophysiologic mechanisms that account for the appearance and distribution of these erosions include osteopenia, soft-tissue laxity, soft-tissue pressure on bone, bone pressure on bone, and muscular forces.  相似文献   
90.
L-Methylmalonyl-CoA mutase (MUT) is an adenosylcobalamin (AdoCbl)- requiring mitochondrial matrix enzyme that catalyzes the isomerization of L-methylmalonyl-CoA to succinyl-CoA. Inherited defects in the gene encoding this enzyme result in the mut forms of methylmalonic acidemia. Expression of mature human MUT cDNA in Escherichia coli at a post- induction cultivation temperature of 12 degrees C, rather than 37 degrees C, led to the folding of the majority of the synthesized protein to a soluble form, with an activity of 0.2-0.3 U/mg protein in the cell-free extract, 10-15 times higher than that in human liver homogenate. Six missense mutations, producing the amino acid changes G94V, Y231N, R369H, G623R, H678R and G717V, were detected in MUT cDNA of patients suffering from the mut- form of methylmalonic acidemia, resulting from defective AdoCbl binding. Two (G623R and G717V) had been reported in other patients. Three (G94V, Y231N and R369H) are the first changes in the NH2-terminal part of the enzyme reported to cause the mut- phenotype. Enzymes with the mutations were individually expressed, and their kinetic parameters were generally in accord with published biochemical data from extracts of fibroblasts from these patients. The mutations increased the K(m) for AdoCbl by 40- to 900-fold, while V(max) values varied from 0.2% to nearly 100% of that of wild-type protein. In one case of a doubly heterozygous cell line, however, neither of the constituent mutant enzymes had a K(m) corresponding to the lower of the two estimated from the extract data. This finding may reflect the natural occurrence of interallelic complementation in vivo in this cell line.   相似文献   
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