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61.
Cystic hygromas (benign tumours of the lymphatic system or lymphangiomas) occur predominantly in the head and neck region of infants and children. They can be grouped into three prognostic categories: (1) simple cystic hygroma; (2) cystic hygroma with oropharyngeal involvement; and (3) cystic hygroma with mediastinal involvement. At the Royal Children's Hospital, Melbourne, during a 16 year period (1973–1988) 47 of 122 (39%) patients admitted with a lymphangioma were classified as cervical cystic hygroma. Simple cystic hygromas, presenting as a lump, occurred in 33 children. In 28, uncomplicated excision was possible. Nine children presented at birth with cystic hygroma with oro-pharyngeal involvement, 5 of whom had severe respiratory distress. All 9 required multiple excisions; death occurred in 1. Cervicomediastinal cystic hygroma occurred in 5 children presenting between birth and 2 years. Mediastinal involvement was confirmed by chest X-ray. All children had thoracocervical excision without early complications; 2 had cervical recurrence. Offprint requests to: N. A. Myers  相似文献   
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In a study of serum cholesterol and triglyceride concentrations in male physicians, blood was drawn after fasting from 2071 registrants at 17 Canadian medical meetings from 1968 to 1973. Eight regional medical laboratories participated in the study. About two thirds of the samples were analysed in one of two laboratories to diminish method variations. When chylomicronemia, hyperglycemia or extremely high triglyceride values were detected, suggesting nonfasting, the data were discarded. The mean serum cholesterol value for the total study population was 233.9 plus or minus 1.22 mg/dl and the mean serum triglyceride value, 150.5 plus or minus 2.48 mg/dl. The mean values and the prevalence of elevated values (cholesterol larger than or equal to 250 mg/dl; triglyceride larger than or equal to 150 mg/dl) were related to age. Of the total study population 34.7% had elevated cholesterol values and 36.2% had elevated triglyceride values; only the cholesterol value was elevated in 17.5%, only the triglyceride value in 19.6% and both values were elevated in 16.8%. Although this was not a random sampling of Canadian physicians or of Canadian men, our findings of elevated serum lipid values were similar to those in French Canadian civic workers, American executives and Scandinavians, and somewhat higher than those in the Albany, New York and Framingham populations, but distinctly higher than those reported by a recent Nutrition Canada survey.  相似文献   
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The ability of s.c. injected tumour cells to specifically inhibit the growth of similar cells injected i.v. 2 days later has been confirmed. The capacity of tumour cells to elicit this effect varies form tumour to tumour. Furthermore, it is more readily achieved with cultured than with freshly excised tumour cells. The superior effect elicited by cultured tumour cells was not overcome by treating them with trypsin or pronase. The protection achieved was impaired in T-cell-depleted mice and mice which had been irradiated (400 rad) prior to pretreatment. In contrast, it was not affected by administration of silica, sodium aurothiomolate or cortisone acetate. The results imply that T-cell-dependent responses are involved in the protection conferred by pre-injecting tumour cells shortly before i.v. challenge.  相似文献   
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Banner  MP; Gohel  VK 《Radiology》1978,129(3):637
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67.
Qayyum A  Goh JS  Kakar S  Yeh BM  Merriman RB  Coakley FV 《Radiology》2005,237(2):507-511
PURPOSE: To retrospectively determine the relative accuracy of liver fat quantification with out-of-phase gradient-echo magnetic resonance (MR) imaging and fat-saturated fast spin-echo MR imaging in patients with and without cirrhosis, with histologic analysis as the reference standard. MATERIALS AND METHODS: Committee on Human Research approval was obtained. Patient consent was not required. Data collection ended before HIPAA regulations were implemented, but patient anonymity was maintained. Twenty-seven patients, 16 with cirrhosis, were retrospectively identified who underwent MR imaging before histopathologic evaluation of liver fat at biopsy or surgery. The patient population consisted of 15 male and 12 female patients (mean age, 55 years; range, 16-75 years). One radiologist blinded to the histopathologic results recorded mean signal intensity derived from three regions of interest placed in the right and left lobes of the liver on three sections and signal intensity of the spleen from one region of interest within the same section. Liver fat was quantified with the relative loss of signal intensity on out-of-phase images compared with that on in-phase T1-weighted gradient-echo images and with relative loss of signal intensity on T2-weighted fast spin-echo MR images obtained with fat saturation compared with those obtained without fat saturation. Hotelling t test was used to compare correlation coefficients between relative signal intensity differences and histopathologically determined percentage of fat. RESULTS: In patients without cirrhosis, liver fat quantification with fat-saturated fast spin-echo MR imaging was significantly better than it was with out-of-phase gradient-echo MR imaging (r = 0.92 vs 0.69, P < .01). In patients with cirrhosis, liver fat quantification was correlated only with fat-saturated fast spin-echo MR imaging (r = 0.76, P < .01); the relative signal intensity loss on out-of-phase gradient-echo MR images was not correlated with histopathologically determined percentage of fat (r = 0.25, P = .36). CONCLUSION: Preliminary results suggest liver fat may be more accurately quantified with fat-saturated fast spin-echo MR imaging than with out-of-phase gradient-echo MR imaging, especially in patients with cirrhosis.  相似文献   
68.
Children tend to choose an entity they cannot already label, rather than one they can, as the likely referent of a novel noun. The effect of input that contradicts this strategy on the interpretation of other novel nouns was investigated. In pre- and posttests, 4-year-olds were asked to judge whether novel nouns referred to "name-similar" familiar objects or novel objects (e.g., whether japple referred to an apple or a binder clip). During an intervening treatment phase, they were asked to pick the referents of novel nouns from pairs of familiar objects (Experiments 1 and 3) or were taught subordinate names for familiar objects (Experiment 2). Most resisted the lure of phonological similarity in the pretest but increased selection of name-similar familiar objects over novel ones in the posttest. In Experiment 3, which involved monosyllables that differed in initial phoneme from the familiar words, treatment produced this effect only when accompanied by a rhyme-sensitization procedure. Experiment 2 included two other age groups: 2-year-olds, who were less resistant to phonological similarity in the pretest and responded to the treatment like the 4-year-olds; and adults, who nearly always selected the novel objects in the pretest and posttest. For children, the impact of treatment was positively associated with ability to detect phonological similarity and negatively associated with vocabulary size.  相似文献   
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Attention-deficit hyperactivity disorder (ADHD) is the most common childhood psychiatric disorder, affecting 5-10% of school-age children. Although the biological basis of this disorder is unknown, twin and family studies provide strong evidence that ADHD has a genetic basis involving multiple genes. A previous study found an association between ADHD and two polymorphisms in the 3' untranslated region (UTR) of SNAP-25, a gene encoding a synaptic vesicle docking protein known to play a role in the hyperactivity observed in the Coloboma mouse strain. In this paper, we test biased transmission of the 3' UTR SNAP-25 haplotype using a larger ADHD sample of 113 families with 207 affected children. Using the transmission disequilibrium test (TDT), we found a trend consistent with biased transmission of the TC haplotype of SNAP-25 in all transmissions and detected a significant distortion (P=0.027) when paternal transmissions were evaluated.  相似文献   
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