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991.
This study investigates the extent to which working memory, motor speed and perceptual processing speed influence Wechsler Adult Intelligence Scale-III (WAIS-III) Processing Speed Index (PSI) scores. Sixty-eight adult outpatients with Traumatic Brain Injury (TBI) of varying severity and complete data on all outcome measures were identified. Two cases with outlying values on one outcome measure were omitted from the final sample. Working memory was measured by the Working Memory Index score from the WAIS-III. Motor speed was measured as score on the Halstead-Reitan Finger Oscillation Test (finger tapping) and perceptual processing as score on the Trail Making Test--Part B. In hierarchical multiple regression analyses, working memory accounted for 10% of the variance in PSI scores, whereas motor speed only accounted for 3%. An independent measure of perceptual processing, Trail Making Test--B, accounted for 26% of the variance in WAIS-III PSI scores. The total variance accounted for by the three factors was 56%. Findings confirm that the WAIS-III PSI scores of individuals who have received a TBI reflect perceptual processing speed, with an additional component attributable to working memory. Motor speed made only a small contribution to WAIS-III PSI scores in the present sample.  相似文献   
992.
Chloroquine-resistant plasmodium falciparum malaria is a serious public health threat that is spreading rapidly across Sub-Saharan Africa. It affects over three quarters (80%) of malarial endemic countries. Of the estimated 300-500 million cases of malaria reported annually, the vast majority of malarial-related morbidities occur among young children in Africa, especially those concentrated in the remote rural areas with inadequate access to appropriate health care services. In Liberia, in vivo studies conducted between 1993 and 2000 observed varying degrees of plasmodium falciparum malaria infections that were resistant to chloroquine, including sulfadiazine-pyrimethamine. As the country emerges from a prolonged civil war, the health care delivery system may not be adequately prepared to implement an effective nation-wide malarial control strategy. As a result, the management of uncomplicated malaria in Liberia poses a significant public health challenge for the government-financed health care delivery system. Therefore, based on extensive literature review, we report the failure of chloroquine as an effective first-line drug for the treatment of uncomplicated plasmodium falciparum malaria in Liberia and recommend that national health efforts be directed at identifying alternative drug(s) to replace it.  相似文献   
993.
Anthropometric screening has been recommended for the detection of undernutrition as it is simple, inexpensive and non-invasive. However, a recent study estimating the prevalence of undernutrition on admission to hospital in Dublin, Republic of Ireland, highlighted that the anthropometric reference data currently available in the UK and Republic of Ireland are inadequate to accurately determine nutritional status. In order to provide current anthropometric data, we carried out a cross-sectional study of 874 free-living, apparently healthy Irish-born elderly individuals aged over 65 years. Height, weight, triceps skinfold thickness, mid-arm and calf circumference were measured, values for BMI, mid-arm muscle circumference and arm muscle area were calculated and smoothed centile data derived for each variable. One-third of these elderly individuals had a BMI between 20-25 kg/m2, approximately two-thirds (68.5 % of males and 61 % of females) were classified as overweight or obese, almost one-fifth having a BMI over 30 kg/m2 (17 % of men and 20 % of women). Very few were underweight, only 3 % having a BMI below 20 kg/m2. Height, weight, BMI and muscle reserves decreased with increasing age. The reduction in muscle size was associated with lower handgrip strength. Fat reserves declined with age in females only. Just over half of elderly Irish women reported participating in active leisure of 20 min duration four or more times/week, although 13 % reported having no involvement in active leisure. These data for the Irish elderly extend the data generated from a recent countrywide survey of Irish adults aged 18-64 years, thus providing suitable reference standards for nutritional assessment of elderly Irish individuals.  相似文献   
994.
One of the widely proposed theories for mucocele formation is sinus ostial obstruction. Accordingly, this study was undertaken to investigate the long-term effects of ostial obstruction in the rabbit maxillary sinus and its potential role in the pathogenesis of mucoceles. Maxillary sinus ostial obstruction was induced on one side in eight Pasteurella-free White New Zealand rabbits using Histoacryl. The rabbits were housed in a Pasteurella-free zone for 24 weeks. At re-exploration, only three of the eight maxillary sinuses where ostial obstruction was induced showed pressure recording consistent with ostial obstruction. Mucociliary clearance activity was assessed using India ink. Swabs for culture were taken from the infected maxillary sinuses. Mucosal specimens for histopathological examination were harvested from one of the maxillary sinuses with obstructed ostium as well as from another sinus with nonobstructed ostium. The three maxillary sinuses with obstructed ostia showed gross evidence of infection and deranged mucociliary clearance, but no mucocele formation. Based on the findings of this study it is concluded that long-term ostial obstruction indeed plays a role in the pathogenesis of chronic sinusitis, but it did not induce mucocele formation in the rabbit maxillary sinus.  相似文献   
995.
Tonsillar tissue is a component of mucosa-associated lymphoid tissue (MALT), which has evolved to protect vulnerable mucosal surfaces. Helicobacter pylori, implicated as an aetiological factor in duodenal ulcers and gastritis, induces the appearance of lymphoid aggregates (MALT) in the stomach. This organism is cytotoxic via a nitric oxide synthase cascade. The possibility that tonsillar tissue processes Helicobacter pylori or that Helicobacter pylori can colonize the palatine tonsils is explored. The study design was that of a prospective study. We determined if Helicobacter pylori (i) forms part of the normal microenvironment of the tonsil, (ii) plays a role in the pathogenesis of tonsillitis and (iii) is associated with increased expression of inducible nitric oxide synthase (iNOS) in macrophages of the tonsil. Serology for Helicobacter pylori was performed on 50 patients undergoing tonsillectomy. Tonsillar specimens were monitored for urease activity by CLO test (a sealed plastic slide holding an agar gel, which contains urea and detects the urease enzyme of Helicobacter pylori), and immunocytochemically probed for Helicobacter pylori and iNOS expression. The mean age of this patient group was 17.2 years (3-36 years). Fourteen (28%) were sero-positive for Helicobacter pylori but no evidence of this pathogen was found in any tonsillar specimen. The number of macrophages staining for iNOS, per field, under a magnification of x40, was increased in sero-positive patients (13.3 +/- 1.3 versus 9.9 +/- 0.7; P = 0.01). Helicobacter pylori does not appear to colonize the tonsil. We believe that Helicobacter pylori primes the tonsils by inducing macrophage iNOS expression. The higher expression in sero-positive patients is a reflection of a pro-inflammatory reaction to Helicobacter pylori that is both local and systemic.  相似文献   
996.
OBJECTIVE: To objectively assess the effect of light reduction as an isolated environmental intervention on neonatal morbidity. STUDY DESIGN: Randomized multicenter trial. Neonates < 1251 g birth weight and < 31 weeks gestational age were randomly assigned to receive goggles or to a control group. Goggles that reduced visible light by 97% were placed within 24 hours of birth and remained in use until 31 weeks postmenstrual age or for a minimum of 4 weeks. RESULTS: Four hundred nine infants were enrolled, and outcome data are reported for 359 surviving infants. There were no significant differences between the groups in weight gain, duration of oxygen therapy, mechanical ventilation, or hospital stay either in the unadjusted analyses or in the analyses adjusted for birth weight, gestational age, race, sex, and inborn (born in study hospital) status. There was no difference between the groups in the incidence of intracranial hemorrhage. CONCLUSIONS: This randomized trial of continuous light reduction in the first few weeks of life for very low birth weight infants showed no effect on medical outcomes.  相似文献   
997.
Videoconferencing was introduced in the Queensland health service in 1995. By the end of 1999, there were more than 150 videoconferencing units in health facilities around the state. Six audits of videoconferencing usage were conducted using similar methodology at six-month intervals from November 1997 to May 2000. Between November 1997 and November 1999, the number of calls more than doubled, from 566 to 1378. Hours of usage almost trebled, from 671 to 1724. The average duration of calls remained similar, at about 1 h 12 min. The proportion of calls involving more than two sites (multipoint videoconferences) increased from 44% to 65%. The majority of the activity was for education (including training). Videoconferencing was also used for administration and clinical care. Mental health staff were the heaviest users, but use by health professionals from other specialty areas increased during the study period. The Queensland health service has realized a number of important benefits from telehealth.  相似文献   
998.
A tele-ophthalmology service was established between a regional hospital in South Africa and a specialist eye hospital in the UK. The aim of the service was to provide secondary specialist advice in the diagnosis and treatment of difficult ophthalmology cases in South Africa. Over 12 months, the South African medical officers saw 16,458 ophthalmology patients and would have liked a second opinion in 5.7% of these cases. Case discussions conducted by videoconferencing at 384 kbit/s were carried out in 0.5% of cases. No significant connection problems were experienced during the 12-month study period. On 4% of occasions, the case discussions were conducted at a bandwidth of 256 kbit/s, but this did not affect the quality of the still images. The South African medical officers valued the educational benefits gained from the case discussions with the UK specialists.  相似文献   
999.
The single rod implant was introduced to the UK in October 1999. This case illustrates a problem encountered with the timing of its insertion and highlights a possible note of caution.  相似文献   
1000.
In the first half of the twentieth century epidemiologic evidence linked elevated incidences of pulmonary fibrosis and cancer with inhalation of chrysotile and crocidolite asbestos, a family of naturally occurring inorganic fibrous materials. As the serpentine and amphibole forms of asbestos were phased out, synthetic vitreous fibers (SVFs; fiber glass, mineral wool, and refractory fiber) became increasingly utilized, and concerns were raised that they too might cause adverse health effects. Extensive toxicological research on SVFs has demonstrated that their pulmonary effects are directly related to fiber dose in the lung over time. This is the result of deposition (thin fibers deposit in the lower lung more efficiently than thick fibers) and lung-persistence ("biopersistence" is directly related to fiber length and inversely related to dissolution and fragmentation rates). In rat inhalation studies, asbestos was determined to be 7- to 10-fold more biopersistent in the lung than SVFs. Other than its effect on biopersistence, fiber composition did not appear to play a direct role in the biological activity of SVFs. Recently, the utilization of man-made organic fibers (MMOFs) (also referred to by some as synthetic organic fibers) has increased rapidly for a variety of applications. In contrast to SVFs, research on the potential pulmonary effects of MMOFs is relatively limited, because traditionally MMOFs were manufactured in diameters too thick to be respirable (inhalable into the lower lung). However, new developments in the MMOF industry have resulted in the production of increasingly fine-diameter fibers for special applications, and certain post-manufacturing processes (e.g., chopping) generate respirable-sized MMOF dust. Until the mid-1990s, there was no consistent evidence of human health affects attributed to occupational exposure to MMOFs. Very recently, however, a unique form of interstitial lung disease has been reported in nylon flock workers in three different plants, and respirable-sized nylon shreds (including fibers) were identified in workplace air samples. Whether nylon dust or other occupational exposures are responsible for the development of lung disease in these workers remains to be determined. It is also unknown whether the biological mechanisms that determine the respirability and toxicity of SVFs apply to MMOFs. Thus, it is appropriate and timely to review the current data regarding MMOF workplace exposure and pulmonary health effects, including the database on epidemiological, exposure assessment, and toxicology studies.  相似文献   
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