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61.
Hepatic Aryl Hydrocarbon Hydroxylase and Cytochrome P450 Inductionfollowing the Transpulmonary Absorption of TCDD from IntratracheallyInstilled Particles. NESSEL, C. S., AMORUSO, M. A., UMBREIT,T. H., AND GALLO, M. A. (1990). Fundam. Appl. Toxicol. 15, 500-509.Inhalation of particles contaminated with 2,3,7,8-tetrachlorodibenzo-p-dioxin(TCDD) will be an increasingly important route of human exposurein light of the increased utilization of municipal waste incinerationand the resultant emission of contaminated materials into theenvironment. The potential for pulmonary absorption of the compoundfrom respirable particles was assessed in the present studyfollowing the intratracheal instillation of TCDD (1) as a contaminantof gallium oxide particles and (2) in a corn oil vehicle. Groupsof five female Sprague-Dawley rats received 0, 0.005, 0.055,0.55, or 5.5 µg/kg TCDD in a single instillation and wereeuthanized 4 days later. Absorption was characterized by enzymeinduction [aryl hydrocarbon hydroxylase (AHH) activity and totalcytochrome P450] and histopathological examination of the liver.Induction of hepatic enzymes was dose-dependent with both treatmentregimes. Up to an 18-fold increase in AHH and an 80% increasein cytochrome P450 were observed in treated animals. Inductionwas slightly higher when animals received TCDD in com oil thanwhen animals received TCDD-contaminated particles and was relativelycomparable to induction following oral exposure. Similar resultswere obtained when animals were treated with particles contaminatedup to 4 weeks prior to instillation. Characteristics of TCDD-inducedhepatotoxicity, including enlarged hepatocytes and fatty infiltration,were apparent in treated rats, but were not present in vehicle-instilledanimals. These results indicate that systemic effects occurfollowing pulmonary exposure to TCDD and that inhalation maybe an important route Of exposure for TCDD.  相似文献   
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63.
We present a case of cutaneous metastases from a primary bladder transitional cell carcinoma (TCC), with a prolonged survival of 23 years. Cutaneous metastases from primary bladder TCC are uncommon and, like all metastases, have a poor prognosis. The common modality of treatment of cutaneous metastases from a primary bladder cancer is wide local excision of the metastases followed by combination chemotherapy. Here, we present a case of a solitary cutaneous metastasis from a primary bladder TCC, which was treated with wide local excision and single agent chemotherapy. Twenty-three years on, the patient remains disease and recurrence free.  相似文献   
64.
A feminist critique of problem gambling research   总被引:5,自引:0,他引:5  
Using a liberal feminist orientation, the literature on a diverse range of topics concerning the profile of the pathological gambler, from personality traits to psychiatric orientation, as well as consequences of the behavior on individuals was reviewed for its gender-related content. The vast majority of this research has been on male subjects; gender of respondents has not been discussed; gender-related findings have not been reported; mostly male-dominated gambling sites have been investigated. To say that most compulsive gamblers are men and therefore, theorists need to explain them first and only later apply these same explanations to the ‘rare’ [female] cases is to acquiesce to a patriarchal notion of the world. Action is suggested which would put a halt to this trend and suggestions are made for future research.  相似文献   
65.
To determine the influence of bacteria and bacterial products on the course of secretory otitis media (SOM) following ventilation tube insertion we examined 68 middle ear effusions from 57 children with SOM. Swabs were taken for bacteriological examination and the content of endotoxin was measured. The children were followed up for one year and relapse of SOM was recorded. Bacteria were present in 38% of effusions and endotoxin was detectable in 96%. Relapse occurred in 26% of the patients and was related to the presence of bacteria in the original effusion (P 0.01). The concentration of endotoxin, however, did not correlate with the course of SOM. Keywords bacteria endotoxin secretory otitis media prognosis  相似文献   
66.
Forty-four 11-year-old children born with a complete unilateral cleft lip and palate were examined to determine the frequency and the extent of changes in the tympanic membrane and the middle ear function and compared with 16 healthy children of the same age. The incidence of hearing impairment, abnormal middle ear pressure, retraction of the pars flaccida and abnormal tympanic membrane appearance were 24, 44, 23 and 67% respectively among the patients while the same parameters in the control group were 0, 12.5, 6 and 12%. Previous grommet insertion in the patient group was statistically correlated to both tympanic membrane abnormality and abnormal middle ear pessure but, remarkably, no association was found between grommet insertion and hearing impairment. The poor middle ear function in the children with cleft lip and palate was probably a result of reduced Eustachian tube function.  相似文献   
67.
68.
Aim We investigated whether preterm birth affects later visuocognitive function and, in particular, whether it affects global and configural perceptual processing differently. Method We compared the performance of 21 healthy preterm children (8 females, 13 males; mean age 7y 8mo, SD 8mo; mean gestational age 29.3wks, SD 1.9; mean birthweight 1186.5g, SD 377.2) with that of a matched term comparison group (8 females, 13 males; mean age 7y 11mo, SD 1y 1mo; mean gestational age >37wks; mean birthweight >2500g) in two perceptual tasks pinpointing differences between local and global and between local and configural processing. Results There was no difference between preterm and term children’s global processing, as both groups showed a bias towards global information (preterm: t[1,20]=2.6, p=0.01; comparison group: t[1,20]=3.0, p=0.01). By contrast, no such typical pattern of performance was found for configural processing as, unlike the comparison group (t[1,20]=7.1, p<0.001), preterm children preferentially relied on local rather than on configural information (t[1,20]=?15.4, p<0.001). Interpretation These findings suggest that preterm birth may have a greater influence on the development of later perceptual skills than originally envisaged. We discuss the results according to the current and dominant view of the visual system.  相似文献   
69.
Aim The objective was to determine whether specific intrinsic (age, pattern of cerebral palsy [CP], child’s motivation) and extrinsic (number of treatments, parenting stress) characteristics were associated with responsiveness to botulinum toxin A (BoNT‐A) injections in children with CP 3 months after injection into the gastrocnemius muscle. Method Children with hemiplegia or diplegia recruited from a BoNT‐A programme were evaluated before and 3 months following injection of BoNT‐A into the gastrocnemius. Outcome measures included muscle tone, range of motion, gait pattern, level of ambulation, gross motor function, and functional independence. Determinants of responsiveness to BoNT‐A considered were age, number of treatments, distribution of CP, parenting stress, and motivation. Results Thirty‐one children were recruited (17 males, 14 females) – 22 with hemiplegia and nine with diplegia. Twenty‐eight were classified at Gross Motor Function Classification System (GMFCS) level I and three at level III. The mean age was 6 years 4 months (SD 2y 11mo). Younger age (p=0.015) and fewer number (p=0.024) of BoNT‐A treatments were associated with greater change in gross motor function. Child’s motivation and parenting stress were significantly associated with improvements in muscle tone (p=0.006–0.017), passive range of motion (p=0.008–0.033), gait pattern (p=0.005–0.042), level of ambulation (p=0.001–0.043), and functional independence (p=0.004–0.027). Interpretation The results indicate that child, family, and treatment characteristics influence the degree of responsiveness to BoNT‐A treatment. The contribution of contextual factors (personal and environmental) on responsiveness may be underappreciated in children with CP.  相似文献   
70.
We report four infants (two males, two females) with ring 14 chromosome presenting with early-onset partial epilepsy. The first seizure occurred between 3 and 6 months (3, 3, 4, and 6mo respectively). In all four cases, diagnosis was based on early focal seizures, rather than on psychomotor retardation or morphological features, which were not prominent at seizure onset. Moreover, despite the young age of the patients and the high frequency of seizures, neither epileptic spasms nor progression to 'epileptic encephalopathy', such as hypsarrhythmia, were observed. Epilepsy remained partial in these patients. At the most recent follow-up, all four children had slight or mild psychomotor delay, and two of them had moderate non-specific dysmorphic traits. Data from the literature about epilepsy in ring 14 chromosome syndrome were also reviewed. Ring 14 chromosome syndrome may be revealed by isolated, early-onset focal epilepsy suggestive of focal lesions with only mild mental retardation and morphological features at the time of diagnosis. The characteristics of these observations differ from classic ring 14 syndrome, and may enlarge this clinical spectrum. Many unanswered questions remain concerning phenotype–genotype correlation and identification of the potential genes and molecular mechanisms responsible for epilepsy in patients with ring 14 syndrome.  相似文献   
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