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991.
992.
L R Frankel N G Anas R M Perkin A B Seid B Peterson S M Park 《Critical care medicine》1984,12(4):395-398
Ten infants with acquired subglottic stenosis were treated successfully using the anterior cricoid split operation. Eight had been preterm infants who required endotracheal intubation and assisted ventilation for the respiratory distress syndrome. Two had been born at term; 1 required mechanical ventilation for aspiration of meconium and the other intubation for obstructive apnea. All had been extubated successfully in less than 2 wk and were discharged home with no signs of subglottic stenosis. These infants were referred at 2 to 13 months of age for evaluation of upper airway obstruction. By bronchoscopy, we confirmed severe subglottic stenosis in each of the infants. The anterior cricoid split procedure requires a single midline vertical incision through the anterior cartilaginous ring of the cricoid cartilage and the upper 2 tracheal rings. Our postoperative management included 7 to 10 days of endotracheal intubation, mechanical ventilation, neuromuscular blockade, sedation, and total parenteral nutrition. All were extubated at the end of this period without evidence of stridor or obstructive apnea. One patient developed a subglottic granuloma at the level of the cricoid cartilage 4 months after the operation; this was successfully excised with the carbon dioxide laser. The other 9 patients remain asymptomatic 1 month to 1 yr after the surgical repair. 相似文献
993.
Effect of Hypersensitivity on Protein Uptake Across the Air-Blood Barrier of Isolated Rabbit Lungs 下载免费PDF全文
Janet F. Braley Laurence B. Peterson Christopher A. Dawson Vernon L. Moore 《The Journal of clinical investigation》1979,63(6):1103-1109
In previous studies with isolated perfused rabbit lungs, we observed that human serum albumin (HSA) and ovalbumin, introduced into the isolated lungs as an aerosol, entered the pulmonary circulation antigenically intact. The "inhaled" proteins were also broken down in the lung. When lungs from animals immunized with one protein inhaled the two proteins simultaneously, absorption of intact antigen was specifically reduced, and there was a nonspecific increase in the appearance of metabolites of both proteins in the blood.In the present study, we investigated the antigen-specific and nonspecific effects of two types of hypersensitivity responses on protein absorption across the air-blood barrier of isolated rabbit lungs. In one group of lungs, an acute hypersensitivity response was induced by introducing HSA into the blood perfusing lungs from HSA-immunized rabbits. In another, the rabbits had been previously exposed to chronic HSA aerosol until their lungs exhibited a chronic immunologic inflammatory response. Lungs from both groups were insufflated simultaneously with HSA, and a nonspecific protein, ovalbumin. Lungs in which the acute anaphylactic response was induced showed no alteration in the absorption of either intact protein compared with HSA-immunized controls, but absorbed a somewhat larger quantity of breakdown products of the specific antigen. Lungs undergoing the chronic alveolar inflammation were more permeable to nonspecific protein than were noninflamed lungs. Despite the increased permeability to nonspecific protein, the absorption of antigen was blocked as effectively as in immune but noninflamed controls. In these chronically inflamed lungs, the absorption of antigen breakdown products was enhanced. The results indicate that both immunologic and inflammatory mechanisms may control the amounts of inhaled soluble proteins that reach the blood via the alveolocapillary barrier. Alterations in the absorption of inhaled proteins and their metabolites across the air-blood barrier during certain types of hypersensitivity responses may be of immunologic and pathologic significance. 相似文献
994.
The fourth component of human complement (C4) is one that is essential to the antibody-mediated classical activation pathway. C4d, present on all normal and most patient red cells (RBCs), may be detected by the human antisera anti-Rodgers (Rg) and -Chido (Ch). A study has been made of the Rg/Ch antigens on normal and patient RBCs in an attempt to understand the mechanism by which C4 is bound to normal RBCs in the absence of RBC antibodies (Abs). Because RBCs from C1q-deficient patients express Rg/Ch, it seems that C1q is not essential for C4 binding. Treatment of normal RBCs with proteolytic enzymes, including trypsin, eliminated positive reactions with anti-Rg/Ch even though the C4d fragment is considered to be resistant to cleavage by trypsin. By correlating agglutination reactions with numbers of bound C4d and C3d molecules, it is evident that both C4d and C3d were affected by trypsin treatment and that anti-Rg/Ch were not capable of agglutinating RBCs with less than 50 molecules of bound C4d. It is concluded that trypsin-sensitive and -insensitive RBC membrane structures may both act as acceptors for C4. RBCs with null phenotypes of the major blood group systems all expressed Rg/Ch antigens, so none of the structures that carry these antigens act preferentially as acceptors for C4. 相似文献
995.
996.
Site Specificity of Pain and Tension in Tension-Type Headaches 总被引:1,自引:0,他引:1
Alan L. Peterson PhD G. Wayne Talcott PhD William J. Kelleher PhD C. Keith Haddock PhD 《Headache》1995,35(2):89-92
Previous studies have not found a significant correlation between location of pain and electromyogram levels in chronic headache patients. However, these studies only examined a limited number of muscle groups and did not assess subjective tension levels. The present study evaluated a group of tension-type (n = 43) and migraine and tension-type (n = 30) headache patients. Measures were obtained at five muscle sites (frontalis, temporalis, masseter, splenius capitis, and trapezius) for patient ratings of headache pain, patient ratings of muscle tension, and electromyogram recordings cross-sectionally. Neither subjective pain nor tension ratings were found to be significantly related to electromyogram levels. The site-specificity relationship between chronic headache pain, subjective report of muscular tension, and electromyogram levels remains unclear. 相似文献
997.
Trichinella infection and clinical disease 总被引:1,自引:0,他引:1
Clausen MR; Meyer CN; Krantz T; Moser C; Gomme G; Kayser L; Albrectsen J; Kapel CM; Bygbjerg IC 《QJM : monthly journal of the Association of Physicians》1996,89(8):631-636
Trichinellosis is caused by ingestion of insufficiently cooked meat
contaminated with infective larvae of <it>Trichinella</it>
species. The clinical course is highly variable, ranging from no apparent
infection to severe and even fatal disease. We report two illustrative
cases of trichinellosis. Returning to Denmark a few days after having eaten
roasted pork in the Republic of Serbia, a female patient suffered from
severe vomiting, epigastric pain, diarrhoea, and later myalgia, generalized
oedema, and prostration. A biopsy showed heavy infestation with
<it>Trichinella spiralis</it>, 2000 larvae/g of muscle.
Life-threatening cardiopulmonary, renal and central nervous system
complications developed. The patient recovered after several months. Her
husband, who also ate the pork, did not have clinical symptoms, but an
increased eosinophil count and a single larva in a muscle biopsy confirmed
infection. The epidemiology, clinical manifestations, diagnosis, treatment
and prevention of trichinellosis are reviewed.
相似文献
998.
Temkin-Greener H Bajorska A Peterson DR Kunitz SJ Gross D Williams TF Mukamel DB 《Medical care》2004,42(8):779-788
OBJECTIVE: The objective of this study was to test the hypothesis that social support is an important predictor of mortality in a frail older population receiving formal long-term care services. RESEARCH DESIGN AND METHODS: The analysis is based on 3138 individuals enrolled in 28 Programs of All-Inclusive Care for the Elderly (PACE). Information about the enrollees is obtained from dataPACE. Semiparametric Cox proportional hazards models are estimated to assess the importance of individual risk factors, program effect, and social support. RESULTS: The introduction of the social support variables into the mortality model containing the sociodemographic, health needs, and the PACE-site indicator variables results in a significant improvement of the overall model fit. Several social support variables are statistically significant predictors of mortality. Controlling for all participant and caregiver characteristics, participants whose caregiver is a spouse have a significantly lower risk of mortality (hazard ratio = 0.63) compared with those whose caregiver is not a spouse. Furthermore, caregivers' assistance with meals confers a significantly lower risk of morality (hazard ratio = 0.66) compared with no assistance with meals. CONCLUSIONS: This study shows that certain aspects of informal caregiving are important factors enhancing survival in a population of frail, nursing home-certifiable individuals enrolled in a health program that already provides extensive services, including personal care, chores, and meals. Further research to better differentiate between the affective versus the instrumental dimensions of social support is needed to guide programs on how to balance the use of resources to provide both the necessary formal services and the support for the informal caregivers. 相似文献
999.
1000.