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231.
Function of integrin in duodenal mucosal uptake of iron   总被引:4,自引:0,他引:4  
Conrad  ME; Umbreit  JN; Peterson  RD; Moore  EG; Harper  KP 《Blood》1993,81(2):517-521
A mechanism for the absorption of inorganic iron in the small intestine is described in which integrins appear to play an important role in the passage of iron across microvillous membranes. Biochemical isolates from microvillous preparations of duodenum from rats dosed with radioiron showed radioactivity concentrated in integrins. The presence of integrins on mucosal surfaces of duodenal cells was confirmed by immunofluorescent microscopy using anti-integrin monoclonal antibodies. Immunoprecipitation methods were used to show that microvillous radioiron was precipitated with anti-integrin antibodies and that mobilferrin, a 56-Kd cytosol iron-binding protein, coprecipitated with integrins. We postulate from these data that the mucosal uptake of iron from the gut lumen is mediated via an integrin-mobilferrin pathway.  相似文献   
232.

BACKGROUND:

Chronic obstructive pulmonary disease (COPD) is associated with significant mortality. It is currently the fourth leading cause of death in Canada and the world.

OBJECTIVES:

To describe the mortality of elderly patients in Ontario after hospital admission for COPD.

METHODS:

A retrospective cohort study was conducted using the Discharge Abstract Database from the Canadian Institute for Health Information. Patients aged 65 years and older who were admitted to hospital between 2001 and 2004 with primary discharge diagnoses labelled with International Classification of Diseases, Ninth Revision codes 491, 492 and 496 were included in the study.

RESULTS:

Mortality rates were 8.81, 12.10, 14.53 and 27.72 per 100 COPD hospital admissions at 30, 60, 90 and 365 days after hospital discharge, respectively. Mortality also increased with age, and men had higher rates than women. No significant differences in mortality rates were found between different socioeconomic groups (P>0.05). Patients with shared care of a family physician or general practitioner and a specialist had significantly lower mortality rates than the overall rate (P<0.05), and their rates were approximately one-half the rate of patients with only one physician.

CONCLUSIONS:

Hospitalization with COPD is associated with significant mortality. Patients who were cared for by both a family physician or general practitioner and a specialist had significantly lower mortality rates than those cared for by only one physician, suggesting that continuous and coordinated care results in better survival.  相似文献   
233.
Spleen colony formation after transplantation of bone marrow cells into irradiated mice has been used as an assay for hematopoietic stem cells (CFU-S), but has serious limitations intrinsic to an in vivo assay. In this report we describe experiments using an in vitro clonogenic assay that is especially suitable for studies of stem cell regulation as defined growth factors and normal untreated bone marrow can be used. We have demonstrated that the colony-forming cells have proliferative properties in common with CFU-S and respond to specific proliferation regulators previously detected using the spleen colony assay.  相似文献   
234.
Cranial duplex sonography of the infant   总被引:1,自引:0,他引:1  
Duplex sonography was used to evaluate the cranial contents of 75 infants. The first 35 were scanned to establish technique and evaluate basic flow patterns. All cranial vessels scanned in healthy term infants produced diphasic (low-resistance) waveforms, although certain cerebral vessels had characteristic Doppler signatures. The pericallosal, callosomarginal, anterior cerebral, basilar, middle cerebral, and internal carotid arteries and the vein of Galen were isolated and evaluated in almost every subject. In the second part of the study duplex characteristics of healthy term infants, healthy preterm infants, preterm infants with intracranial hemorrhages, and hydrocephalic infants were evaluated. Relative flow velocity at peak systole and end diastole and pulsatility index were investigated. The most significant variable was gestational age. Preterm infants frequently had no forward flow during diastole. Duplex sonography does not appear to add significant diagnostic information to routine real-time cranial studies. It does, however, permit more exact evaluation of cerebral blood flow than does non-pulse-gated, nondirected Doppler scanning.  相似文献   
235.
236.
In 1997, Narchi and Kulaylat, studying the incidence of Down syndrome in infants of gestational diabetic mothers, concluded that maternal diabetes increases the risk for Down syndrome, but failed to control the maternal age in their analysis. Using data from the Spanish Collaborative Study of Congenital Malformations (ECEMC), we analyzed the relationship between Down syndrome and maternal diabetes mellitus, and maternal gestational diabetes, controlling the maternal age through the pair‐matching analysis, stratifying by maternal age and logistic regression analysis. The analyses show that maternal age is related either to Down syndrome as well as to both types of maternal diabetes. Thus, the overall analysis could be confounded by maternal age. Once we controlled the maternal age, the risk of maternal diabetes mellitus for Down syndrome is: odds ratio (OR) = 0.92 (0.41–2.07); P = 0.83. Controlling maternal age in gestational diabetes, the risk is OR = 1.18 (0.61–2.35); P > 0.70. Based on our results, we conclude that Down syndrome is related to maternal age, but does not seem to be related to any type of maternal diabetes. © 2002 Wiley‐Liss, Inc.  相似文献   
237.
In the health sector, planning and resource allocation at country level are mainly guided by national plans. For each such plan, a midterm review of progress is important for policy-makers since the review can inform the second half of the plan’s implementation and provide a situation analysis on which the subsequent plan can be based. The review should include a comprehensive analysis using recent data – from surveys, facility and administrative databases – and global health estimates. Any midterm analysis of progress is best conducted by a team comprising representatives of government agencies, independent national institutions and global health organizations. Here we present an example of such a review, done in 2013 in the United Republic of Tanzania. Compared to similar countries, the results of this midterm review showed good progress in all health indicators except skilled birth attendance.  相似文献   
238.

Background  

The study of the seasonal variation of disease is receiving increasing attention from health researchers. Available statistical tests for seasonality typically indicate the presence or absence of statistically significant seasonality but do not provide a meaningful measure of its strength.  相似文献   
239.
Cortical bone metastases   总被引:1,自引:0,他引:1  
Coerkamp  EG; Kroon  HM 《Radiology》1988,169(2):525-528
The data on 26 patients with solitary metastatic lesions arising in cortical bone were studied. Nineteen patients were over 50 years of age. In 19 patients, the cortical metastasis was the first indication of the presence of a primary malignant condition. In seven cases, cortical metastases developed in patients with a known primary tumor. The primary tumors involved were eight renal cell carcinomas, six bronchogenic carcinomas, two carcinomas of the gastrointestinal tract, one osteosarcoma, one neuroblastoma, one melanoma, one hepatoma, one carcinoma of the breast, and one thyroid carcinoma. In four cases, the primary tumor remained unknown. A metastatic origin should be considered in the differential diagnosis of an osteolytic lesion arising in the cortex of a long bone, especially in older patients and in patients with a known primary malignant condition. The cortical bone metastases encountered in this study did not originate solely from bronchogenic carcinoma, as has been reported by other authors. Cortical metastases are probably less rare than has been hitherto assumed.  相似文献   
240.
Direct laser light, in combination with percutaneous transluminal angioplasty (PTA), was used to recanalize atherosclerotic peripheral arteries. Argon laser energy was controlled with an optical assembly and aligned with a special centering/dilation balloon so that plaque tissue absorbed laser energy directly and was vaporized. A channel was thereby created with multiple 10-W laser exposures (2-10 seconds), and conventional angioplasty was then performed. Recanalization was achieved in 33 of 36 procedures (92%), in 23 femoropopliteal (mean length, 9 cm) and three iliac total occlusions and ten femoropopliteal high-grade stenoses, with the three failures occurring in the first group. Complications included two emboli, six moderate groin hematomas, and one laser perforation. While these results are preliminary (mean follow-up, 3 months), direct laser angioplasty appears to be a useful adjunct to PTA for treating atherosclerotic arteries.  相似文献   
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