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81.
Preterm parturition is a syndrome caused by several mechanisms of disease, including intrauterine infection/inflammation, uteroplacental ischemia, uterine overdistension, cervical disease, maternal/fetal stress, abnormal allogeneic responses, allergic reactions, and unknown insults. An allergic-like mechanism was proposed as a potential etiology for the preterm parturition syndrome, based on the observation that eosinophils were present in the amniotic fluid in a fraction of women with preterm labor and a history of allergy, coupled with the observation that conditioned media from degranulated mast cells (the effector cells of type 1 hypersensitivity) induced contractility of human myometrial strips. This communication describes a case of a pregnant woman who had an allergic reaction and regular uterine contractions after the ingestion of lobster meat, to which she was known to be allergic. Preterm labor subsided after the treatment of antihistamines and steroids. The patient subsequently delivered at term. At follow-up, the child was diagnosed with atopy and asthma, and required frequent use of inhaled corticosteroids and β-2 adrenergic agents. The immunological basis for preterm labor induced by an allergic-like reaction (hypersensitivity) is reviewed.  相似文献   
82.
Adenoids are known as immunosecretory organs and those in atopic children present cellular and cytokine profiles different from those of non‐atopic children. We hypothesized that locally produced total IgE and allergen‐specific antibodies could be involved in the inflammatory responses in adenoid tissue. Local productions of total IgE and Dermatophagoides pteronyssinus (DP)‐specific IgE, IgA, IgG1, and IgG4 antibodies were evaluated, as well as their relationships with the markers of allergic inflammation within adenoid tissue. Eighteen atopic subjects, who were sensitized to more than one common aeroallergen, and 22 non‐atopic subjects undergoing adenotonsillectomy, were recruited. Immunoassays using adenoid tissue homogenate were performed to quantify the levels of total IgE, eosinophil cationic protein (ECP), and mast cell tryptase. DP‐specific IgE, IgA, IgG1, and IgG4 antibodies, soluble IL‐2 receptors (sIL‐2R), soluble CD23 (sCD23), and IL‐6 were measured by ELISA. All parameters measured in adenoid tissue homogenate were presented as a ratio to the albumin level found in the adenoid. Median level of total IgE in adenoid tissue homogenate was significantly higher in atopic individuals than in non‐atopic individuals. Median values of DP‐specific IgE and IgA antibodies were significantly higher in atopics than in non‐atopics (p = 0.001, p = 0.006, respectively), while no differences were seen in DP‐specific IgG1 and IgG4 antibodies. ECP and sCD23 levels in adenoid homogenate were significantly higher in atopics than in non‐atopics (p = 0.026, p = 0.048, respectively), while no significant differences were noted in tryptase, sIL‐2R, and IL‐6 levels. The levels of DP‐specific IgE, IgA, IgG1, and IgG4 antibodies in adenoid homogenate correlated significantly with ECP levels, but not with those of sIL‐2R, sCD23, and IL‐6. The presence of total IgE and DP‐specific antibodies in adenoid tissue was confirmed to be more prominent in atopics. In conclusion, locally‐produced total IgE and DP‐specific antibodies may contribute to eosinophilic inflammation in adenoid tissue in atopic children.  相似文献   
83.
Many candidate gene studies for atopic dermatitis (AD) and associated phenotypes have been conducted so far, but replication of significant results has been a major problem. Two loss of function polymorphisms FLG R501X- and 2282del4, in the Filaggrin ( FLG ) gene encoding for an epidermal barrier protein were recently identified. They were reported to be predisposing factors for AD and concomitant asthma. Several groups confirmed the initial results in independent populations. The aim of this study is to further investigate the importance of these FLG variants in the development of AD and subsequent asthma symptoms in pre-school children, we investigated children and parents of the Early Treatment of the Atopic Child (ETAC)-trial. We genotyped 496 children and 488 parents of the ETAC population for the two FLG variants, evaluating an association by family based analysis (transmission disequilibrium test). We found a highly significant association of the FLG null variants R501X- and 2282del4 with AD (combined genotype p < 0.0001) and asthma (combined genotype p < 0.0001). The replication and its statistical significance underlines the importance of the FLG polymorphisms and the importance of the skin barrier function in the development of AD and subsequent asthma.  相似文献   
84.
INTRODUCTION: The Leipzig Allergy High-Risk Children Study (LARS) is a prospective nested cohort control study about the influence of chemical indoor exposure in dwellings on the health outcome of atopy-risk children during the first years of life. DESIGN AND METHODS: 475 premature children and children with allergic risk factors have been selected out of the 1995/1996 birth cohort in the city of Leipzig. Twenty-five volatile organic compounds (VOC) were measured in the infant's bedrooms using passive sampling systems for 4 weeks after birth. The babies underwent a medical examination at the age of six weeks and 1 year. The parents answered a questionnaire. RESULTS: Correlations between VOC exposures and infections were calculated by multiple logistic regression. Selected VOC show a direct association to actually painted dwellings (OR = 2.4; 95% Cl 1.1-5.3). An increase of risk of pulmonary infections was observed in infants aged 6 weeks if restoration (painting OR 5.6; 95% Cl 1.3-24.0) or flooring connected with painting had occurred during the pregnancy period. Higher concentration of styrene (> 2.0 micrograms/m3, indicator for flooring) elevated the risk of pulmonary infections in six-week-old infants (OR = 2.1; 95% Cl 1.1-4.2). Environmental benzene > 5.6 micrograms/m3 increased the risk of airway infections in six-week-old babies (OR = 2.4; 95% Cl 1.28-4.48). Smoking in the dwelling (OR = 2.0; 95% Cl 1.1-3.5) as well as restoration (OR = 1.9; 95% Cl 1.1-3.5) are also risk factors of the development of wheezing in the one-year-old child. CONCLUSIONS: The data give indications in order to prevent allergies and chronic lung diseases in atopy risk children exposure to chemicals from indoor air should be minimised from birth on.  相似文献   
85.
ABSTRACT. Out of 242 children (10 and 14 years of age) in one school-district 221 (93 %) were evaluated for atopy/allergy by a questionnaire, interview, physical examination and determination of S-IgE and IgE-antibodies (RAST) to pollen, animal danders and house dust mite. Eighteen months after the initial examination all 221 children were re-interviewed. All children with previous or current symptoms of atopy/allergy, all children with positive RAST despite a negative history and 20 non-atopic/non-allergic RAST-negative children were tested with a skin prick test (SPT). At the initial examination the cumulative incidence of atopy/allergy was 32.6% and positive RAST was obtained in 40 children (18.1%). At the follow-up the incidence of atopic/allergic symptoms during the last 18 months was 25.8%. The current prevalence of allergy to pollen and danders, assessed by interview only, was 19 % and 9 % respectively while determined by both interview and positive SPT 15 % and 5 % respectively. The mean S-IgE (78 kU/l) of the children with current symptoms differed significantly ( p <0.001) from that (19 kU/l) of the non-atopic ones. There was no relationship between S-IgE and the stage of puberty. Ten of the 11 children with positive RAST, but no atopy/allergy intially, developed clinical atopy/allergy during the follow-up.  相似文献   
86.
Asthma is one of the most common chronic diseases in childhood; it is caused by a complex interaction between genetic factors and exposure to environmental allergens and irritants. Previous studies using the candidate gene approach showed that asthma was linked to a number of susceptibility genetic loci in Caucasian subjects. There are, however, only a few studies on asthma predisposition genes in the Chinese population. We studied the distribution of allele frequencies of I50V for the interleukin-4 receptor, two polymorphisms in intron 2 and exon 7 for the high-affinity IgE receptor (Fc epsilon RI-beta), R16G and E27Q for the beta(2)-adrenoceptor,and R275Q (824G/A) for CC chemokine receptor 3 in Chinese children.Seventy-six patients, with a mean age of 10.6 years, and 70 age- and sex-matched controls, were studied. Significantly more subjects in the asthma group had specific IgE antibodies against environmental allergens (P < 0.0001; odds ratio, 9.82). Genotyping of the six genetic markers showed that none of the six polymorphisms was associated with asthma in this cohort. The allele frequencies of I50V, R16G, and E27Q in our population were similar to those published for Asian subjects but not Caucasians. The R275Q substitution was a rare finding in our study and in the published reports.Our results demonstrate ethnic differences in polymorphisms of atopy candidate genes. Additional studies involving larger samples are required to investigate the association between asthma or atopy and the genotypes studied to date in Chinese children.  相似文献   
87.
In vivo corneal confocal microscopy in keratoconus   总被引:1,自引:0,他引:1  
PURPOSE: To evaluate the corneas of keratoconic subjects using in vivo confocal microscopy. METHODS: Slit scanning confocal microscopy was used to evaluate the central cornea of one eye of each of 29 keratoconic subjects (mean age 31 +/- 10 years; range 16-49 years). Quantitative aspects of corneal morphology were compared against data from control subjects. RESULTS: Compared with normal control corneas, epithelial wing cell nuclei were larger (p < 0.0001) and epithelial basal cell diameter was larger (p < 0.05) in the keratoconic cornea. Many of the keratoconic corneas investigated showed increased levels of stromal haze and reflectivity, which appeared to be related to the presence of apical scarring on slit lamp examination. A grading scale was devised to quantify the levels of haze. This scale was shown to provide a measure of the level of scarring present. The anterior keratocyte density (AKD) and posterior keratocyte density were 19% lower (p < 0.0001) and 10% lower (p = 0.004) than in controls, respectively. The reduction in AKD was significantly associated with three factors: a history of atopy, eye rubbing and the presence of corneal staining. The mean endothelial cell density in keratoconus was 6% greater than that of normal controls (p = 0.05). The level of endothelial polymegethism was shown not to be different between keratoconic subjects and matched controls (paired t-test: t = 1.82, p = 0.08). CONCLUSIONS: Confocal microscopy demonstrates significant quantitative alterations of corneal morphology in keratoconus.  相似文献   
88.
The Childhood Origins of Asthma (COAST) study   总被引:6,自引:0,他引:6  
  相似文献   
89.
90.
Asthma and atopy – the price of affluence?   总被引:2,自引:0,他引:2  
Von Hertzen LC  Haahtela T 《Allergy》2004,59(2):124-137
Irrespective of improved knowledge of many aspects of atopic diseases, the unfavorable trends in their prevalence particularly among children could not have been reversed. A growing body of evidence suggests that something may lack from our societal affluence that has the capacity to provide protection against the development of atopic diseases. Much attention during the last years has been devoted to the hygiene hypothesis. This review outlines the impact of environment and lifestyle, particularly from the perspective of the East-West gradient, on the development of atopic diseases, with a special emphasis on the hygiene hypothesis in its broadest sense.  相似文献   
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