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131.
Simple and sensitive normal and reverse flow injection methods for spectrophotometric determination of thiamine hydrochloride (THC) at the microgram level were proposed and optimized. Both methods are based on the reaction between THC and diazotized metoclopramide in alkaline medium. Beer’s law was obeyed over the range of 10–300 and 2–90 μg/mL, the limits of detection were 2.118 and 0.839 μg/mL and the sampling rates were 80 and 95 injections per hour for normal and reverse flow injection methods respectively. The application of both methods to commercially available pharmaceuticals produced acceptable results. The flow system is suitable for application in quality control processes.  相似文献   
132.
The use of wireless sensor networks (WSN) in healthcare applications is growing in a fast pace. Numerous applications such as heart rate monitor, blood pressure monitor and endoscopic capsule are already in use. To address the growing use of sensor technology in this area, a new field known as wireless body area networks (WBAN or simply BAN) has emerged. As most devices and their applications are wireless in nature, security and privacy concerns are among major areas of concern. Due to direct involvement of humans also increases the sensitivity. Whether the data gathered from patients or individuals are obtained with the consent of the person or without it due to the need by the system, misuse or privacy concerns may restrict people from taking advantage of the full benefits from the system. People may not see these devices safe for daily use. There may also possibility of serious social unrest due to the fear that such devices may be used for monitoring and tracking individuals by government agencies or other private organizations. In this paper we discuss these issues and analyze in detail the problems and their possible measures.  相似文献   
133.
Uric acid is a product of purine metabolism and has been linked to gout and kidney calculi. Chronic kidney disease (CKD) and hypertension (HTN) are two major public health problems, and both are associated with increased risk of cardiovascular events. Emerging evidence suggests a pathogenic role of hyperuricemia in the development of HTN and CKD, in addition to progression of CKD, by inducing renal inflammation, endothelial dysfunction, and activation of the renin-angiotensin system. In addition, several epidemiological studies have linked hyperuricemia with an increased risk of HTN and CKD. A few clinical trials have assessed the use of uric acid-lowering therapies such as allopurinol and febuxostat in the management of HTN and delaying progression of CKD. To date, most of these trials are short-term with a small sample size; however, their results are encouraging and provide a rationale for larger randomized controlled trials to establish the role of uric acid-lowering therapies in the management of HTN, in addition to prevention of CKD progression and cardiovascular events.  相似文献   
134.
A simple, safe, easily reproducible and quick method of taking lung biopsy in diffuse interstitial lung disease is described.  相似文献   
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136.
The assessment of markers of systemic inflammation, such as C-reactive protein (CRP) and interleukin 6 (IL6), could be used to identify persons at high risk of coronary heart disease (CHD). This study evaluates the relationship of CRP and IL6 with CHD risk factors in patients with type 2 diabetes mellitus (DM) with CHD and age and sex matched type 2 DM controls without CHD. CRP, IL-6, total plasma homocysteine (tHcy), lipoprotein (a) [Lp(a)] and sialic acid (SA) were determined in 55 type 2 diabetic patients with CHD and 51 age- and sex-matched type 2 diabetic controls without CHD. Multivariate and logistic regression analyses were used to relate these markers with CHD risk factors. CRP (P=0.02) and tHcy (P=0.03) were significantly higher in patients with CHD compared with the control group even after correction for age and sex. IL6, Lp(a), SA and lipid parameters were not significantly different between the two groups of patients. After adjustment for potential confounders, the odds ratio (OR) for elevated CRP was 2.00 (95% confidence interval [CI], 1.12-3.58) (P=0.02) but the OR for IL6 was 3.41 95% CI, 0.70-17.17 (P=0.14). Partial correlation analyses of CRP and IL6 with other variables showed significant correlation of CRP with tHcy, and SA in patients with CHD only. Our results support the inclusion of CRP (high-sensitivity assay), in the risk assessment of diabetic subjects.  相似文献   
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138.
The objective of the study was to determine the degree of linear growth retardation of patients with vitamin D deficiency rickets at presentation and the magnitude of catch-up growth in relation to their calcium (Ca) homeostasis and hormones affecting it before and after treatment. This prospective study recorded the anthropometric data and measured the circulating 25-hydroxy vitamin D (25-OH-D), insulin-like growth factor I (IGF-I), parathyroid hormone, Ca, phosphate, and alkaline phosphatase concentrations in 46 infants and children with nutritional (vitamin D deficiency) rickets before and 6 months or more after treatment with one intramuscular injection of vitamin D3 megadose (300000 IU). Forty normal age- and sex-matched children were included as controls for the auxological data. At presentation, patients' mean age = 13.1 +/- 1.1 months, length standard deviation scores (LSDS) = -1.5 +/- 0.2, and body mass index = 16.3 +/- 0.85. They were significantly shorter and had markedly lower growth velocity standard deviation scores (GVSDS) compared with normal controls (LSDS = 0.25 +/- 0.18 and 0.31 +/- 0.22, respectively). Six months after treatment, the LSDS increased significantly in patients to -0.45 +/- 0.13, with a significantly increased GVSDS (2.76 +/- 0.45) and body mass index (16.9 +/- 0.65). They were still shorter but with significantly higher GVSDS compared with normal controls. Serum Ca and phosphate concentrations increased from 2.07 +/- 0.25 and 1.23 +/- 0.24 mmol/L, respectively, before treatment to 2.44 +/- 0.2 and 1.94 +/- 0.2 mmol/L, respectively, after treatment. Serum alkaline phosphatase and parathyroid hormone concentrations decreased from 1183 +/- 219 U/L and 294 +/- 87 pg/mL, respectively, before treatment to 334 +/- 75 U/L and 35.2 +/- 15.2 pg/mL, respectively, after treatment. The 25-OH-D level increased from 4.5 +/- 0.56 ng/mL before treatment to 44.5 +/- 3.7 ng/mL after treatment. Circulating concentrations of IGF-I increased significantly after treatment (52.2 +/- 18.9 ng/mL) vs before treatment (26.6 +/- 12.8 ng/mL). The 25-OH-D concentrations were correlated significantly with the IGF-I levels before and after treatment (r = 0.603 and r = 0.59, respectively; P < .001). The GVSDS after treatment was correlated with the increase of IGF-I and 25-OH-D levels (r = 0.325 and r= 0.314, respectively; P < .01). These data denote that the accelerated linear growth after treatment of nutritional vitamin D deficiency is mediated through activation of the growth hormone/IGF-I system and suggests an important role of vitamin D as a link between the proliferating cartilage cells of the growth plate and growth hormone/IGF-I secretion. Three different sequential stages of vitamin D deficiency can be recognized according to the clinical/radiological, biochemical, and hormonal data of patients at presentation.  相似文献   
139.
140.

Objective:

There is an ongoing interest in the relationship between vitamin D status and diabetes control and complications. However, data from Saudi Arabia are limited. To determine the impact of vitamin D status on glycemic control and cardiometabolic complications of children and adolescents with type 1 diabetes mellitus (T1DM) attending a tertiary care diabetes clinic in Saudi Arabia.

Methods:

Demographic, clinical, and laboratory data of 301 children and adolescent subjects with T1DM (53.5% females) of a mean age of 13.9 years attending King Abdulaziz Medical City-Jeddah during 2010-2013 were retrospectively collected. Relationships between vitamin D status and frequency of hypoglycemia, hemoglobin A1c (HbA1c) level, body mass index (BMI), blood pressure, and lipid profile were evaluated.

Results:

The mean duration of diabetes was 7.7±3.7 years. Mean BMI value was 21.1±4.5 kg/m2 and HbA1c was 9.6±1.9% in both genders. Only 26.2% of the patients had a satisfactory HbA1c level. The mean level of 25-hydroxyvitamin D [25(OH)D] was 35.15 and that of cholesterol was 4.75. Vitamin D deficiency [25(OH)D≤37.5 nmol/L] was detected in 63.6% of the male and 67.7% of the female subjects. In males, it was inversely associated with frequency of hypoglycemia (p<0.01), BMI (p<0.05), diastolic blood pressure (p<0.05), and triglyceride levels (p<0.01), while in females, it was inversely associated with current age (p<0.05), age at diagnosis (p<0.01), and triglyceride levels (p<0.01). No significant correlation between HbA1c and vitamin D deficiency was observed.

Conclusion:

Vitamin D deficiency was highly prevalent in our study sample and was found to be associated with frequency of hypoglycemic episodes and with adverse cardiometabolic control.  相似文献   
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