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31.
Objective : To review experience of CYP11β1 deficiency (previously known as 11β-hydroxylase) at the Royal Children's Hospital, Melbourne, Victoria.
Methodology : A retrospective case review was conducted from 1974 to 1995 with five cases identified.
Results : Age of presentation ranged from 1 day to 7 years. Presentation was with ambiguous genitatia at birth (two females), simple virilization (two males) and suspected early puberty in mid childhood (one female). Associated clinical features were hypertension (three cases) and tall stature with markedly advanced bone age (four cases). Biochemical abnormalities consistent with CYP11β1-deficiency were elevated urinary tetrahydro-11-deoxycortisol ( n = 5) and elevated serum 11-deoxycortisol ( n = 3). Additional abnormalities were elevated 17-hydroxyprogesterone ( n = 3), elevated androstenedione ( n = 4) and elevated dehydroepiandrosterone sulphate ( n = 4). The clinical features and investigations suggested CYP11β1-classical deficiency in four patients and CYP11β1-non-classical deficiency in one patient.
Conclusions : The five cases of CYP11β1-deficiency demonstrate a spectrum of clinical abnormalities, with diagnostic difficulties in two cases and delayed presentation in three cases. Prompt diagnosis of CYP11β1-deficiency is facilitated greatly by the availability of a gas chromatography-mass spectrometry instrument and is essential to avoid the long-term effects of hypertension and hyperandrogenism.  相似文献   
32.
The angiographic findings in a patient with haemophilic pseudotumour of the femur are presented. The examination showed the position of the displaced femoro-poplited vessels, enabling these structures to be avoided at operation. Under anti-haemophilic globulin cover no complications occurred. It is suggested that angiography may be safely employed provided the coagulation defect is controlled. The examination may be useful in differentiating other bone lesions and in defining more clearly the extent of a haemophilic pseudotumour.  相似文献   
33.
BACKGROUND: Secondary heating appliances are important indoor sources of air pollution, including particulate matter, nitrogen dioxide (NO2), and sulfur dioxide (SO2). We hypothesized that the use of secondary heating sources increases respiratory symptoms in women living in nonsmoking households and specifically that concentrations of SO2 and NO2 emitted from heating sources are associated with respiratory symptoms. METHODS: Mothers who delivered babies at 12 hospitals in Connecticut and Virginia (1993-1996) were enrolled. There were 888 women who contributed symptom and exposure information during the winter heating season (15 October to 15 April), for a total of 9783 reporting periods (median = 12 reporting periods per woman, interquartile range 11-12). Adjusted rate ratios (RRs) of effects of source use and measured concentrations on rate of days with symptoms were obtained using generalized estimating equations for a log-linear Poisson model, controlling age, education, race, history of allergies, number of children, dwelling type, and residence state. RESULTS: In adjusted models, each hour-per-day increase in kerosene heater use is associated with an increase in wheezing (RR = 1.06; 95% confidence interval (CI) = 1.01-1.11). Each hour of fireplace use is associated with increased cough (1.05; 1.01-1.09), sore throat (1.04; 1.00-1.08), and marginally with chest tightness (1.05; 0.99-1.12). Each 10 ppb increase in SO2 (a proxy for sulfate aerosol) is associated with increased wheezing (1.57; 1.10-2.26) and chest tightness (1.32; 1.01-1.71). CONCLUSIONS: Emissions from fireplaces, gas space heaters, and kerosene heaters may contribute to respiratory symptoms in a population of nonsmoking women.  相似文献   
34.

Background  

We sought to evaluate the hypothesis that the high incidence of cutaneous melanoma in white persons in central Alabama is associated with a predominance of Irish and Scots descent.  相似文献   
35.
Some patients with chronic asthma develop irreversible airflow obstruction. Our aim was to assess whether reported duration of asthma and induced sputum cell counts were associated with pulmonary function in patients with asthma who did not smoke.Maximal forced expiratory volume in the first second (FEV(1)) was determined following a steroid trial (oral prednisolone, 30 mg/d [n = 92 patients]; or inhaled fluticasone, 2000 microg/d [n = 5]; for 2 weeks) and 2.5 mg of nebulized albuterol. Asthma history was recorded with duration from first diagnosis. All subjects were nonsmokers, or were to have stopped smoking > or =5 years previously and smoked < or =5 pack-years (n = 12). Induced sputum was obtained from 59 subjects for analysis of airway cell counts.Maximal FEV(1) was inversely associated with asthma duration (r = -0.47, P <0.0001), age (r = -0.40, P <0.0001), and the proportion of sputum neutrophils (r(s) = -0.50, P = 0.00004). After adjusting for age, both duration of disease and sputum neutrophils were independently associated with maximal FEV(1). Neutrophil activation, as measured by sputum myeloperoxidase levels, was positively associated with the proportion of sputum neutrophils (r(s) = 0.45, P = 0.0004) and inversely associated with maximal FEV(1) (r(s) = -0.59, P <0.0001).Long disease duration may be a predisposing factor for the development of irreversible airflow obstruction in patients with chronic asthma. The negative associations of sputum neutrophil count and activation with maximal FEV(1) suggest that neutrophils may be involved in the pathophysiology of irreversible airflow obstruction in asthma.  相似文献   
36.
There is accumulating evidence from clinical trials and cohort studies that highly active antiretroviral combination therapy is effective at halting immunologic and clinical progression of human immunodeficiency virus (HIV). Its impact at a population level is less well known because the regimes may be difficult to tolerate and compliance poorer. The authors make use of population data for almost all of the HIV-infected people in Scotland in 1997 who were under clinical care and monitor their response to therapy during the first year when these effective treatments became widely available. More than two thirds of the HIV-positive patients were on some form of antiretroviral therapy during the year. The authors show that all treated groups, even those who were on changing regimes, showed net improvement in immunologic status during the year. For the group of patients on triple or quadruple therapy, there was an average increase of more than 100 CD4 cells/mm(3) over the year, with other treatment groups showing more modest, but significant, increases.  相似文献   
37.
The distinction between true and suspected poisoning in children has not been made clear in previous work on childhood poisoning. A study of suspected poisoning in children under 15 years of age in a defined population of North East Bristol from November 1970 to July 1973 carried out by the Health Education Council Medical Research Division included 53,000 child-years at risk. The number of suspected poisonings was 3-4/1000 population aged under 15 years per year, with a higher incidence in younger age groups. Detailed investigation of the circumstances of the accidents carried out by a multidisciplinary team showed that at least 65%, and possibly as many as 78% were poisoning scares and not true poisoning. The evidence used by the casualty doctor and by the parents to diagnose poisoning was explored, and in many cases was circumstantial. Children with fathers in nonmanual occupations were over-represented. This may reflect differences in patterns of utilization behaviour rather than true differences in incidence.  相似文献   
38.
魔芋精粉的降血糖作用   总被引:6,自引:0,他引:6  
目的:研究魔芋精粉的降糖作用。方法:以不同剂量魔芋精粉ig正常小鼠和四氧嘧啶糖尿病小鼠,连续10d后,葡萄糖氧化酶法测定正常小鼠的空腹血糖、糖耐量试验以及四氧嘧 啶糖尿病小鼠的血糖尿病小鼠的血糖,以放射免疫法测定血清胰岛素。结果:魔芋精粉有降低正常小鼠血糖作用,呈一定量效关系趋势;且具有改善小鼠糖耐量作用,能明显降低四氧嘧啶糖尿病小鼠血糖,但因清胰岛素水平无明显影响。结论:魔芋精粉可能是通过影响糖代  相似文献   
39.
40.
Dysphagia as the Sole Manifestation of Bilateral Strokes   总被引:2,自引:0,他引:2  
Dysphagia can be caused by a host of factors, most of which are structural or functional. However, despite extensive evaluations, a certain number of patients have unexplained dysphagia. We present an extremely unusual case whereby a patient with an acute left hemispheric cerebral vascular accident presents with dysphagia as his sole complaint and after extensive neurological, gastroenterological, and radiographic examinations is found to have cricopharyngeal dysfunction. The etiology of this defect was not at all clinically apparent and, ultimately, magnetic resonance imaging (MRI) was performed which revealed a chronic infarction of the right frontal lobe and a smaller acute infarction in the same location of the left. This case demonstrates that swallowing disorders may be the sole presentation of stroke and that, if extensive evaluations of such patients fail to yield an etiology, one must strongly consider MRI as a tool for diagnosis, even if a CT scan is negative.  相似文献   
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