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81.

Background:

The bipolar hip prostheses after some time functions as a unipolar device. There is a need to change the design of bipolar hip prostheses to make it function as a bipolar device over a prolonged period of time. A bicentric bipolar hip prosthesis was used as an implant for various conditions of the hip. We evaluated the movement of this newly developed prosthesis at the interprosthetic joint radiologically at periodic intervals.

Materials and Methods:

Fifty two cases were operarted with the Bicentric bipolar prosthesis for indications like fracture neck of femur and various other diseases of the hip and were followed up with serial radiographs at periodic intervals to evaluate, what fraction of the total abduction at the hip was occurring at the interprosthetic joint.

Results:

In cases of intracapsular fracture neck of femur, the percentage of total abduction occurring at the interprosthetic joint at 3 months follow-up was 33.74% (mean value of all the patients), which fell to 25.66% at 1.5 years. In indications for bipolar hemireplacement other than fracture neck of femur, the percentage of total abduction occurring at the interprosthetic joint at 3 months follow-up was 71.71% (mean value) and at 1.5 years it was 67.52%.

Conclusion:

This study shows the relative preservation of inner bearing movement in the bipolar hip prosthesis with time probably due its refined design. Further refinements are needed to make the prosthesis work better in patients of intracapsular fracture neck femur.  相似文献   
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The relationship between smoking habit and risk of colon and rectal cancers was considered in a case–control study conducted between 1991 and 1996 in six Italian centers. Cases were 1225 patients below age 75 with histologically confirmed cancer of the colon and 728 with cancer of the rectum.Controls were 4154 patients admitted to hospital for a wide spectrum of acute, non-neoplastic diseases. Compared to neversmokers, the odds ratios (OR) for current smokers of 25 or more cigarettes/day was 0.90 for patients with colon and 0.86 for those with rectal cancer and those for ex-smokers were 1.02 and 1.09 for colon and rectal cancer, respectively. No increase in risk was found with duration of the habit, the OR for 40 or more years being 0.79 for colon and 0.87 for rectal cancer. Furthermore, no relationship was apparent with time since starting (the OR for 40 or more years were 0.94 for colon and 1.01 for rectal cancer), or age at starting (the OR for < 18 years were 1.02 for colon and 1.00 for rectal cancer), or for pack-years smoked (the OR for 40 or more pack-years were 0.93 for colon and 0.91 for rectal cancer) or time since stopping among ex-smokers. No increase in risk was found in smokers of 15 cigarettes/day for 40 years or longer (OR: 0.93). No significant heterogeneity was found across strata of age at diagnosis, sex, education, physical activity at work, intake of alcohol, coffee, vegetables, total energy, and number of meals/day. Likewise, no significant association was apparent for various intestinal subsites. Thus, this study did not find cigarette smokers at higher risk for cancer of the bowel even after a long duration and a long period since starting.  相似文献   
84.
The relationship between menopause and non-fatal acute myocardial infarction (AMI) was considered by analysing data from a case-control study conducted in Italy between 1983 and 1992. Cases were 429 women, below age 75 years, with a first episode of non-fatal AMI, admitted to 30 coronary care units; controls were 863 women admitted to the same network of hospitals for acute diseases other than cardiovascular, neoplastic, or hormone-related. Postmenopausal women were not at higher risk of AMI than pre/perimenopausal women, after adjustment for age and other selected covariates [multivariate odds ratio (OR) 0.99]. With reference to age at menopause, compared with women reporting menopause when <45 years, the multivariate OR were 1.54 for those aged 45-49 at menopause, 1.36 for those aged 50-52 years, and 0.97 for those aged >/=53, in the absence of any trend in risk. No meaningful relationship emerged with time since menopause (OR 0.85 for <10 years since menopause). The results were similar in women aged <60 and >/=60 years at AMI. Although the present study does not support a substantial relationship between menopause and non-fatal AMI, the overall epidemiological evidence is compatible with a moderate association.  相似文献   
85.
In a registry of 15,520 patients treated for symptomatic deep vein thrombosis or pulmonary embolism (PE), the 90-day mortality was 8.65% and death was attributed to PE in 1.68% of patients (19.4% of all deaths). Multivariate analysis defined five simple predictors of death from PE during the first 3 months after presentation. The odds ratio for fatal PE was raised to 5.4 by initially nonmassive symptomatic PE (compared with deep vein thrombosis and no symptoms of PE), to 17.5 by initially massive PE (systolic blood pressure below 90 mmHg), 4.9 by immobility as a result of neurological disease, 2.5 by age over 75 years, and 2.0 by the presence of cancer. Of all the deaths from PE, 75% occurred within 12 days of presentation and 50% occurred within 5 days. These results reinforce previous observations that also linked symptomatic PE, massive PE, old age, and cancer to a raised likelihood of death from PE despite appropriate therapy.  相似文献   
86.
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Chronic renal disease is known to alter olfactory function, but the specific changes induced in olfactory organs during this process remain unclear. Of the uraemic toxins generated during renal disease, high levels of urea are known to induce hyposmic conditions. In this study, the effects of environmental exposure to elevated concentrations of urea (7, 13.5 and 20 g L?1) on the sensory mucosa of zebrafish in acute toxicity and chronic toxicity tests were described. It was observed that lamellae maintained structural integrity and epithelial thickness was slightly reduced, but only following exposure to the highest concentrations of urea. Pan‐neuronal labelling with anti‐Hu revealed a negative correlation with levels of urea, leading to investigation of whether distinct neuronal subtypes were equally sensitive. Using densitometric analysis of immunolabelled tissues, numbers of Gα olf‐, TRPC2‐ and TrkA‐expressing cells were compared, representing ciliated, microvillous and crypt neurons, respectively. The three neuronal subpopulations responded differently to increasing levels of urea. In particular, crypt cells were more severely affected than the other cell types, and Gα olf‐immunoreactivity was found to increase when fish were exposed to low doses of urea. It can be concluded that exposure to moderate levels of urea leads to sensory toxicity directly affecting olfactory organs, in accordance with the functional olfactometric measurements previously reported in the literature.  相似文献   
89.
90.
Red meat intake and cancer risk: a study in Italy   总被引:7,自引:0,他引:7  
Meat intake has been positively associated with risk of digestive tract cancers in several epidemiological studies, while data on the relation of meat intake with cancer risk at most other sites are inconsistent. The overall data set, derived from an integrated series of case-control studies conducted in northern Italy between 1983 and 1996, included the following incident, histologically confirmed neoplasms: oral cavity, pharynx and esophagus (n = 497), stomach (n = 745), colon (n = 828), rectum (n = 498), liver (n = 428), gallbladder (n = 60), pancreas (n = 362), larynx (n = 242), breast (n = 3,412), endometrium (n = 750), ovary (n = 971), prostate (n = 127), bladder (n = 431), kidney (n = 190), thyroid (n = 208), Hodgkin's disease (n = 80), non-Hodgkin's lymphomas (n = 200) and multiple myelomas (n = 120). Controls were 7,990 patients admitted to hospital for acute, non-neoplastic conditions unrelated to long-term modifications in diet. The multivariate odds ratios (ORs) for the highest tertile of red meat intake (>/=7 times/week) compared with the lowest (相似文献   
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