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Objective  Exposure to polychlorinated biphenyls (PCBs) is considered to have culminated between 1950 and 1970 in Japan, and exposure through diet, the major exposure route, has decreased significantly over the last 10 years. The primary goal of the present study was to investigate the long-term trends and congener profiles of serum and dietary levels of PCBs using historical samples. Methods  Using banked samples collected in 1980, 1995, and 2003 surveys, we determined the daily intakes and serum concentrations of 13 PCB congeners (#74, #99, #118, #138, #146, #153, #156, #163, #164, #170, #180, #182, and #187) in women. Results  The total daily PCB intake [ng/day, geometric mean (geometric standard deviation)] decreased significantly from 523 (2.5) in 1980 to 63 (3.2) in 2003. The serum total PCB level (ng/g lipid) in women <40 years of age decreased significantly from 185 (1.8) in 1980 to 68 (1.8) in 2003. In contrast, the level in women >50 years of age increased significantly from 125 (1.7) in 1980 to 242 (1.7) in 2003. Specifically, the serum concentrations of hexa (#138, #146, #153, #156, #163, and #164) and hepta (#170, #180, #182, and #187) congeners increased significantly. A comparison of the serum PCB levels of women born from 1940 to 1953 revealed that their serum total PCB level was significantly higher in the 2003 survey [242 (1.7), n = 9] than in the 1995 [128 (2.0), n = 17] surveys. This increase in the total PCB level was attributable to increases in the hepta congener groups. Conclusion  Present results suggest a decreased rate of elimination of hepta congeners with aging in females, rather than a birth-generation phenomenon.  相似文献   
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Pediatrics metabolic syndrome (MetS) may be associated with the risk of development of chronic diseases in adulthood; however, the definition of pediatric MetS is unclear, and may vary with ethnicity. The primary goal of this study was to determine the best anthropometric predictors for pediatric MetS. For this purpose, 988 high school girls were recruited. Anthropometric indices and biochemical parameters were measured using standard procedures. The adapted MetS for pediatrics, including the IDF, NCEP, and two modified-NCEPs (Cook's and DeFerranti's) were used to establish a diagnosis of MetS. Statistical analysis was performed using SPSS and MedCalc softwares. Except for body frame size (r), the values for anthropometric indices were significantly lower in an individual without MetS. Waist to height (WHtR), BMI and hip circumference (HiC) showed the strongest association with the different MetS definitions. For the IDF definition, the highest sensitivity and specificity were observed for HiC (100.0, 85.2) and WHtR (100.0, 84.7); while for the NCEP definition, the r index showed the highest sensitivity (85.0); but low specificity made it inapplicable. For the Cook's definition of MetS, wrist circumference (WrC), HiC, WHtR, BMI and SR had similar sensitivity values with WC (92.9%), and HiC (85.3%) have the highest specificity. WHtR (86.05, 80.5), SR (86.05, 82.7) and HiC (76.7, 87.0) sensitivity and specificity were the best indexes for DeFerranti's criteria. Based on this date, we concluded that HiC and WHtR might be helpful as auxiliary indexes for pediatric MetS definition; however, further studies are required in both genders.  相似文献   
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Integrin alphavbeta6 is generally not expressed in adult epithelia but is induced in wound healing, cancer, and certain fibrotic disorders. Despite this generalized absence, we observed that alphavbeta6 integrin is constitutively expressed in the healthy junctional epithelium linking the gingiva to tooth enamel. Moreover, expression of alphavbeta6 integrin was down-regulated in human periodontal disease, a common medical condition causing tooth loss and also contributing to the development of cardiovascular diseases by increasing the total systemic inflammatory burden. Remarkably, integrin beta6 knockout mice developed classic signs of spontaneous, chronic periodontal disease with characteristic inflammation, epithelial down-growth, pocket formation, and bone loss around the teeth. Integrin alphavbeta6 acts as a major activator of transforming growth factor-beta1 (TGF-beta1), a key anti-inflammatory regulator in the immune system. Co-expression of TGF-beta1 and alphavbeta6 integrin was observed in the healthy junctional epithelium. Moreover, an antibody that blocks alphavbeta6 integrin-mediated activation of TGF-beta1 initiated inflammatory periodontal disease in a rat model of gingival inflammation. Thus, alphavbeta6 integrin is constitutively expressed in the epithelium sealing the gingiva to the tooth and plays a central role in protection against inflammatory periodontal disease through activation of TGF-beta1.  相似文献   
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ObjectivesThe purpose of this study was to examine the influence of semi-rigid foot orthoses on forefoot–rearfoot joint coupling patterns in individuals with different navicular drop measures during heel–toe running.DesignTen trials were collected from twenty-three male subjects who ran slowly shod at 170 steps per minute (2.23 m/s) with a semi-rigid orthoses and without.MethodsForefoot–rearfoot coupling motions were assessed using a vector coding technique during four intervals across the first 50% of stance. Subjects were divided into two groups based on navicular drop measures. A three way ANOVA was performed to examine the interaction and main effects of stance interval, orthoses condition and navicular drop (p < 0.05).ResultsThere were no interaction effects among stance interval, orthoses condition, or navicular drop (p = 0.14) whereas an interaction effect of orthoses condition and stance interval was observed (p = 0.01; effect size = 0.74). Forefoot–rearfoot coupling motion in the no-orthoses condition increased from heel-strike to foot-flat phase at a rate faster than the orthoses condition (p = 0.02).ConclusionsFoot orthoses significantly decrease the forefoot–rearfoot joint coupling angle by reducing forefoot frontal plane motion relative to the rearfoot. Navicular drop measures did not influence joint coupling relationships between the forefoot and rearfoot during the first 50% of stance regardless of orthotic condition.  相似文献   
66.
Ruptured abdominal aorta aneurysm (rAAA) is the 13th leading cause of death in the United States. Despite many advances in the field of vascular surgery, the improvement in mortality rates of rAAA have been very modest. Although endovascular repair has surpassed open repair for elective AAA repair in the United States, open rAAA repair remains the most common therapy for this devastating vascular emergency. In this article, we discuss open surgical management for rAAA. We also describe a fast-track algorithm we have developed at the University of Massachusetts where open and endovascular repairs play equally important roles in management of rAAA.  相似文献   
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The mutation spectrum of CYP1B1 among 104 primary congenital glaucoma patients of the genetically heterogeneous Iranian population was investigated by sequencing. We also determined intragenic single nucleotide polymorphism (SNP) haplotypes associated with the mutations and compared these with haplotypes of other populations. Finally, the frequency distribution of the haplotypes was compared among primary congenital glaucoma patients with and without CYP1B1 mutations and normal controls. Genotype classification of six high-frequency SNPs was performed using the PHASE 2.0 software. CYP1B1 mutations in the Iranian patients were very heterogeneous. Nineteen nonconservative mutations associated with disease, and 10 variations not associated with disease were identified. Ten mutations and three variations not associated with disease were novel. The 13 novel variations make a notable contribution to the approximately 70 known variations in the gene. CYP1B1 mutations were identified in 70% of the patients. The four most common mutations were G61E, R368H, R390H, and R469W, which together constituted 76.2% of the CYP1B1 mutated alleles found. Six unique core SNP haplotypes were identified, four of which were common to the patients with and without CYP1B1 mutations and controls studied. Three SNP blocks determined the haplotypes. Comparison of haplotypes with those of other populations suggests a common origin for many of the mutations.  相似文献   
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