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1.
The motor mechanisms associated with gastric emptying of nutrient liquids are unclear. Gastric emptying and motility were determined in seven healthy volunteers using an MRI technique following ingestion of 500 ml of (1) 10% and (2) 25% dextrose labeled with 1 mM Gd-DOTA. Emptying was determined with transaxial scans and motility during fast coronal scans 1.2 sec apart. Emptying was slower after ingestion of 25% dextrose. Following both meals, proximal gastric diameter remained relatively constant, while antral contractile frequency and depth varied markedly. These variations were greater after 10% dextrose. These studies suggest that antral motility changes contribute to slowing of gastric emptying by nutrient meals.  相似文献   
2.
BackgroundMultimorbidity of intestinal cancer (IC), type 2 diabetes (T2D) and obesity is a complex set of diseases, affected by environmental and genetic risk factors. High‐fat diet (HFD) and oral bacterial infection play important roles in the etiology of these diseases through inflammation and various biological mechanisms.MethodsTo study the complexity of this multimorbidity, we used the collaborative cross (CC) mouse genetics reference population. We aimed to study the multimorbidity of IC, T2D, and obesity using CC lines, measuring their responses to HFD and oral bacterial infection. The study used 63 mice of both sexes generated from two CC lines (IL557 and IL711). For 12 weeks, experimental mice were maintained on specific dietary regimes combined with co‐infection with oral bacteria Porphyromonas gingivalis and Fusobacterium nucleatum, while control groups were not infected. Body weight (BW) and results of a intraperitoneal glucose tolerance test (IPGTT) were recorded at the end of 12 weeks, after which length and size of the intestines were assessed for polyp counts.ResultsPolyp counts ranged between 2 and 10 per CC line. The combination of HFD and infection significantly reduced (P < .01) the colon polyp size of IL557 females to 2.5 cm2, compared to the other groups. Comparing BW gain, IL557 males on HFD gained 18 g, while the females gained 10 g under the same conditions and showed the highest area under curve (AUC) values of 40 000‐45 000 (min mg/dL) in the IPGTT.ConclusionThe results show that mice from different genetic backgrounds respond differently to a high fat diet and oral infection in terms of polyp development and glucose tolerance, and this effect is gender related.  相似文献   
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Objectives. We examined the impact of geographic residency status and census tract (CT)-level socioeconomic status (SES) on colorectal cancer (CRC) outcomes.Methods. This was a retrospective cohort study of patients diagnosed with CRC in Georgia for the years 2000 through 2007. Study outcomes were late-stage disease at diagnosis, receipt of treatment, and survival.Results. For colon cancer, residents of lower-middle-SES and low-SES census tracts had decreased odds of receiving surgery. Rural, lower-middle-SES, and low-SES residents had decreased odds of receiving chemotherapy. For patients with rectal cancer, suburban residents had increased odds of receiving radiotherapy, but low SES resulted in decreased odds of surgery. For survival, rural residents experienced a partially adjusted 14% (hazard ratio [HR] = 1.14; 95% confidence interval [CI] = 1.07, 1.22) increased risk of death following diagnosis of CRC that was somewhat explained by treatment differences and completely explained by CT-level SES. Lower-middle- and low-SES participants had an adjusted increased risk of death following diagnosis for CRC (lower-middle: HR = 1.16; 95% CI = 1.10, 1.22; low: HR = 1.24; 95% CI = 1.16, 1.32).Conclusions. Future efforts should focus on developing interventions and policies that target rural residents and lower SES areas to eliminate disparities in CRC-related outcomes.For men and women in the United States, colorectal cancer (CRC) ranks third in incidence and mortality among cancers, with an estimated 142 820 new cases and 50 830 deaths in 2013.1 Reflecting the US population distribution according to geography2 and evidence of similar incidence rates3,4 for rural residents, approximately 20% of incident CRC cases are expected to occur in rural populations. Although CRC incidence is equivalent for rural and urban residents, CRC mortality is higher in rural populations,5 and the causes of rural versus urban disparities in CRC mortality are not well understood. Compared with their suburban and urban counterparts, rural citizens are more likely to be older, live in poverty, have less education, lack health insurance, and have no regular health care provider.6–9 These facets of rural living pose challenges to accessing health promotional messages and high-quality primary care, not to mention treatment of cancer.10,11Those of lower socioeconomic status (SES) have worse health-related outcomes than their more affluent counterparts, and SES often has a gradient effect on health.12 A challenge in studying the association between rurality and health is being able to disentangle the confounding effect of SES associated with geographic residency.13 As we previously demonstrated for a sample of urban and rural residents of Georgia with CRC, rural residence was associated with an increased risk of death following diagnosis.14 A limitation of that study was an inability to account for SES differences between urban and rural populations. If adjustment for SES explains the poorer survival that is associated with rural residence, this explanation provides an opportunity to investigate mediators of the SES effect as potential avenues for intervention.15 Identification of these mediating factors will facilitate the development of focused interventions with the goal of eliminating rural CRC-related disparities.16,17Building on our previous work,14 we evaluated the independent and combined effects of rurality and area-level SES on CRC outcomes. In our previous study, (1) we were unable to evaluate the independent and potential confounding effect of SES on rurality,2 (2) our study population was a sample of the Georgia CRC population, and (3) residents were classified as urban or rural at the county level, which may have resulted in misclassification. In the present study, the exposures of interest were geographic residency status (rural, suburban, or urban) and area-level SES, both at the census tract (CT) level. In addition, the study population represents the entire state of Georgia rather than a sample. The primary study outcome was overall survival. Secondarily, we wanted to evaluate the effect of SES and geography adjusted for SES on the odds of late-stage disease at diagnosis and receipt of first-course treatment.The findings of this study are meant to bring importance to a highly relevant area of public health research: disparities related to rural versus urban cancer outcomes, and specifically to rural CRC outcomes. As a result, interventions may be designed and policies developed to address the difficulties of accessing and providing high-quality cancer care in rural areas of the United States.11 It is through the combination of applying what is learned from epidemiological findings to community-level interventions and policymaking that the elimination of health disparities will occur.18  相似文献   
5.
A case of diphallus is reported in a Saudi male born with two independent phalli with two urethras, the right urethra being joined by a third urethra opening on the perineum. In addition, the child had an absent right 1st rib, a 3rd thoracic hemivertebra, an absent left kidney, and a spinal lipoma.  相似文献   
6.
Risk factors for injury in middle school football players   总被引:2,自引:0,他引:2  
BACKGROUND: Little is known about the frequency of or risk factors for injuries in middle school or junior high school football players. PURPOSE: To examine the associations of player characteristics (injury history, conditioning, player position, special equipment) and physical parameters (body mass index, weight, height, grip strength) with risk of injury. STUDY DESIGN: Prospective cohort study. METHODS: We documented risk factors for injury in 646 middle school football players, 10 to 15 years of age, in the Oklahoma City, Oklahoma, school district during the 1998 and 1999 seasons. Player characteristics and physical parameters were measured at the beginning of both seasons. Logistic regression methods were used to determine whether baseline variables were associated with the odds of subsequent injury. RESULTS: More playing experience was the only variable significantly associated with the risk of injury in multivariate analyses. This association was observed regardless of the type of injury and even after indirectly controlling for time at risk of injury by restricting analyses to first-string players. Increasing age was significantly associated with the risk of fractures. CONCLUSIONS: Results suggest that physical characteristics play a minor role in risk of injury from football in this age group.  相似文献   
7.
A 28-year-old lady with a long history of pain at left subcostal margin, referred by the gynecologist after her ultrasound showed an incidental splenic cyst while she was being investigated for a gynecological complaint.  相似文献   
8.
BACKGROUND: Cancer screening with highly sensitive, specific biomarkers that reflect molecular phenotypic alterations is an attractive strategy for cancer control. We examined whether biomarker profiles could be used for risk assessment and cancer detection in a cohort of Chinese workers occupationally exposed to benzidine and at risk for bladder cancer. METHODS: The cohort consisted of 1788 exposed and 373 nonexposed workers, followed from 1991 through 1997. We assayed urothelial cells from voided urine samples for DNA ploidy (expressed as the 5C-exceeding rate [DNA 5CER]), the bladder tumor-associated antigen p300, and a cytoskeletal protein (G-actin). Workers were stratified into different risk groups (high, moderate, and low risk) at each examination based on a predefined biomarker profile. For workers who developed bladder cancer, tumor risk assessment was analyzed from samples collected 6-12 months before the cancer diagnosis. The associations between risk group and subsequent development of bladder cancer were analyzed by Cox proportional hazards regression analysis and logistic analysis, after adjustment. All statistical tests were two-sided. RESULTS: Twenty-eight bladder cancers were diagnosed in exposed workers and two in nonexposed workers. For risk assessment, DNA 5CER had 87.5% sensitivity, 86.5% specificity, an odds ratio (OR) of 46.2 (95% confidence interval [CI] = 8.1 to 867.0), and a risk ratio (RR) of 16.2 (95% CI = 7.1 to 37.0); p300 had 50.0% sensitivity, 97.9% specificity, an OR of 40.0 (95% CI = 9.0 to 177.8), and an RR of 37.9 (95% CI = 16.8 to 85.3). The risk of developing bladder cancer was 19.6 (95% CI = 8.0 to 47.9) times higher in workers positive for either the DNA 5CER or p300 biomarkers than in workers negative for both biomarkers and 81.4 (95% CI = 33.3 to 199.3) times higher in workers positive for both biomarkers. G-actin was a poor marker of individual risk. CONCLUSIONS: Occupationally exposed workers at risk for bladder cancer can be individually stratified, screened, monitored, and diagnosed based on predefined molecular biomarker profiles.  相似文献   
9.
A blinded, retrospective study of histological sections from ten hydrocarbon-exposed and twenty unexposed nephrectomized renal cell carcinoma cases was conducted to evaluate the histopathologic features present in the apparently normal kidney parenchyma removed with the tumor. Tissue sections from each of the thirty cases were independently reviewed by three consulting pathologists and scored using well defined criteria. Occupational hydrocarbon exposure indices were developed by a team of industrial hygienists and applied to the detailed occupational history of each exposed case. A positive correlation was observed between age and the total renal pathology score (rs = .40, p less than .03). No correlation was found between indices of occupational hydrocarbon exposure and renal pathology scores among exposed cases. No significant differences in renal pathology scores were noted when exposed cases were matched to unexposed cases by age, sex, and race. These results are limited by the inclusion of only cases with historical hydrocarbon exposures. It is recommended that a follow-up study be conducted, utilizing sensitive quantitative methods, to define what, if any, cytopathologic renal effects occur in conjunction with current occupational exposures to hydrocarbons.  相似文献   
10.
Occupational hydrocarbon exposure and risk of renal cell carcinoma   总被引:2,自引:0,他引:2  
A population-based case-control study (210 cases and 210 age- sex- and frequency-matched population controls) was conducted to evaluate the association between occupational hydrocarbon exposure and risk of renal cell carcinoma. Retrospective estimates of lifetime occupational hydrocarbon exposure were made without regard to case or control status, and an exposure index was calculated based on time and score combinations. A weak positive association was found for hydrocarbon exposure in males only (odds ratio = 1.6). For those under the age of 60, exposure to moderate levels of hydrocarbons produced the highest risk, while for those over the age of 70 a dose-response relationship was found. Those overweight were at high risk for renal cell carcinoma, and there was positive interaction between hydrocarbon exposure and overweight. Alcohol use alone or in the presence of hydrocarbon exposure decreased the risk significantly.  相似文献   
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