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91.
Three small peptides with a typical cysteine-rich domain (TFF or P-domain) display a specific folding structure (trefoil); they are abundantly expressed on mucosal surfaces of normal and neoplastic gastrointestinal tissues. This epithelial location coincides with mucin secretion and, although not proven beyond doubt, this association is suggestive of their function in maintenance of surface integrity. Using normal colon epithelium, premalignant lesions and tumor samples and specific antibodies we studied expression of these peptides in colorectal carcinomas. RT PCR was performed to extend the sensitivity of the assays. While coexpression of pS2, hITF, MUC1 and MUC2 was demonstrated, MUC5 was absent and no simultaneous activity of pS2 and SML1 (as in gastric mucosa and carcinoma) was noted in rectal tumors. Actively transcribed and expressed cytokeratin 20 and GAPDH were used as experimental controls for immunostaining and RT-PCR, respectively.  相似文献   
92.
A review of the current knowledge of mucosal immune response development indicates that migration of immunocytes to mucosal surfaces is an early event during fetal life. The morphologic development of gut-associated lymphoid tissues (lymphoid follicles, Peyer's patches and tonsils) occurs from 11-20 weeks' gestation upwards. But they are active only after birth, when usually antigenic challenge takes place. The complete development of secretory immunity is a postnatal achievement. In infancy, some environmental factors such as feeding and oral antigenic challenge seems to modulate immune response development. Breastfeeding, by means of antiinfectious, antiinflammatory and immunomodulating properties, besides completing infant secretory immunity, also stimulates immunological maturation on mucosal surfaces.  相似文献   
93.
The present article presents the sociological analysis of the nursing profession, focussing the specificities of the profession on the basis of the component elements of a profession, according to the theoretical system of the sociology of professions. At the end of the 20th century and the beginning of the new millennium, nursing faces crucial questions for the profession, which bring back the need to restructure the strategic considerations that make up the political agenda of the nursing profession. Specific knowledge, professional qualification, particularities of the work process, monopoly of the professional exercise, and the configuration of the hierarchy of the nursing team are some of the items dealt within this article. As one of the essential professions in the health area, nursing needs to reach the next century with a new perspective, knowing how and in which conditions it will develop in a context of paradigmatic changes. Considering this new context, a political agenda for nursing professionals will have to contemplate the several aspects that make up a profession, that is, specific knowledge, exclusive labor market, form of organization, among others.  相似文献   
94.
The aim of this study was to evaluate the prevalence, behavioural patterns, and determinants of smoking among a large sample of high-school students from Porto, the second largest city in Portugal, information on sociodemographic characteristics and personal history of tobacco, alcohol, coffee, and illicit drug use was obtained from 2974 students, aged 12-19 years (48.7% female, 51.3% male), using an anonymous self-administered questionnaire. Crude and adjusted odds ratios (OR) were calculated by logistic regression analysis to estimate the association between smoking and the characteristics evaluated. Overall, 35.8% students had never smoked, 39.4% had tried it ("experimental" smokers) but were not smokers, 3.3% were former smokers, 6.6% occasional smokers, and 14.9% regular smokers. The mean age for starting smoking was 13.4 +/- 2.1 years for males and 13.4 +/- 1.6 years for females. The prevalence of current smoking was higher among males than females, but the difference was not significant. Male students were significantly more likely to smoke more cigarettes per day than were females. The prevalence of smoking was significantly associated with the following variables: being aged > 12 years; having parents who had attended school for < 4 years; having a mother (OR = 1.88), siblings (OR = 1.96) or friends (OR = 1.75) who smoked; low academic performance (OR = 1.74 for one or two failures and OR = 2.27 for more than two failures at school); and consumption of coffee (OR = 2.90), alcohol (OR = 3.53), or illicit drugs (OR = 6.69). The prevalence of smoking among adolescents increased with age. There is therefore a need for school-based tobacco prevention programmes which also deal with family influences on smoking.  相似文献   
95.
With the increasing use of obstetric echography fetal hydronephrosis has been reported more frequently. The purpose of this study was to identify prognostic factors associated with adverse outcome, such as renal failure and death, in fetal hydronephrosis. One hundred and forty-eight children with fetal hydronephrosis were admitted, submitted to a systematic protocol, and prospectively followed. Prognostic factors associated with fetal echography and clinical and laboratory findings on admission were studied. The median follow-up was 39 months. The analysis was conducted in two steps. In a univariate analysis, variables associated with adverse outcome were identified by the Kaplan-Meier method. The variables that were significantly associated with adverse outcome were then included in a multivariate analysis. This analysis, using the multivariate Cox’s model, was performed to identify variables that were independently associated with a worse prognosis. Only variables that remained independently associated with adverse outcome were included in the final model. After final adjustment by Cox’s multivariate model, three variables were identified as independent predictors of adverse outcome: oligohydramnios, prematurity, and glomerular filtration rate lower than 20 ml/min. Thus, in the presence of oligohydramnios, prematurity, and abnormal renal function, the medical team must plan appropriate follow-up for infants at health centers prepared to investigate and treat uropathies in newborns. Received: 24 August 1998 / Revised: 7 December 1998 / Accepted: 11 December 1998  相似文献   
96.
Machado L  Rafal RD 《Neuroreport》1999,10(15):3143-3148
The current study investigated whether an ipsilesional bias in line bisection, a conventional measure for diagnosing hemispatial neglect, persists even in the absence of this syndrome in patients with chronic lesions restricted to posterior association cortex or dorsolateral prefrontal cortex. Both left and right hemisphere parietal lesions produced ipsilesional bisection errors, and to a comparable degree. Patients with lesions in frontal cortex, on the other hand, did not show a consistent bias. We conclude that chronic parietal lesions produce an ipsilesional bias in line bisection, even in the absence of other clinical signs of neglect, and that left hemisphere lesions can affect line bisection to the same degree as right hemisphere lesions.  相似文献   
97.
The objectives of this article are to propose indicators for evaluation of the quality of hospital management of bronchial asthma patients, based on explicit criteria from literature reviews. The central problem identified in the literature review is the erroneous evaluation of severity of asthma crises, either by patients and their relatives, or by health professionals at all levels of care, causing serious consequences not only for the patient, but for society as a whole. Mortality figures indicate that from 1980 to 1990, an average of 2000 deaths per year from asthma occurred in Brazil, of which 70% occurred in hospital. Asthma was the fourth cause of hospitalization (hospital admissions), in the state of Rio de Janeiro in 1993. Only 12% of the admissions that resulted in death made use of the ICU. The above information highlights the need for a thorough evaluation of hospital care of bronchial asthma in Brazil, including a review of all admissions resulting in death and reviews of a sample of all bronchial asthma admissions. Proposed criteria are for this evaluation include: severity of the crise, treatment prescribed, information given to the patient and their relatives, and follow-up appointments made after discharge from hospital.  相似文献   
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