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101.
Introduction: Breast cancer is multifactorial therefore more recognition of risk factors is important in its prevention. Objective: This study was conducted in order to determine the factors influencing breast cancer in women referred to health centers in Guilan province in 2015-2016. Method: In a case- control study, 225 women with breast cancer were investigated. The control group consisted of 225 healthy women of the relatives (third-rank) whose phone numbers were obtained from the patients. Data were collected through telephone interviews. Results: The risk of breast cancer raised in women who have a family history of other cancers (OR= 3.5; 95% CI= 1.96-6.6) ,exposure to X-Ray (OR= 2.5; 95% CI=1.1-5.5), having more than 4 children (OR= 2.695% CI=1.2-4.8), age more than 36 years at first pregnancy(OR=2.3; 95% CI=0.7-5.1),primary levelof education (OR= 5.4;95% CI=2.8-11.2) and inadequate intake of fruit (OR=1.5; 95% CI=1-2.2). Also, presence of the following factors reduced breast cancer risk: regular menstruation (OR= 0.66; CI=0.4- 0.9), duration of breastfeeding more than 12 months, less than 6 months and 7-12 months (OR=0.23; 95% CI=0.09-0.59 , OR=0.29; 95% CI=0.17-0.49 and OR=0.03; 95% CI=0.01-0.08) and parity (OR=0.4; 95% CI=0.27-0.83) In multiple linear regression analysis of higher education (OR=0.16; 95% CI=0.03-0.77), using contraceptives for more than 16 years (OR=2.3; 95% CI=1.4-3.9), family history of other cancers (OR=6.1; 95% CI=1.9-19.3) and a history of X-Ray exposure (OR=4.4; 95% CI=1.07-18.1) were considered as predictive factors. Conclusion: The results of this study emphasize the importance of informing women about breast cancer risk factors. So, identification of these risk factors is required as important means of prevention and treatment of breast cancer.  相似文献   
102.
A large proportion of women with lymph node negative breast cancer do not benefit from chemotherapy. Proliferation markers have been shown to recognize patients at high risk for recurrence. The Ki67 protein has recently been included in the St Gallen guidelines. The authors investigated the prognostic importance of cyclin B1 in node negative breast cancer and included a study of reproducibility. In a population‐based case‐control study, 190 women who died from breast cancer were defined as cases and 190 women alive at the time for the corresponding case's death were defined as controls. Inclusion criteria were tumor size ≤50 mm, no lymph node metastases, and no adjuvant chemotherapy. Tumor tissue was immunostained for cyclin B1. Two investigators (EN‐M and AK) evaluated the staining independently by counting approximately 100, 200, 500, and 1000 cells. Cyclin B1 was statistically significantly associated to breast cancer death, in both uni‐ and multivariate analyses (adjusted for tumor size, age, and endocrine therapy), with odds ratios 2–3 for both investigators. The agreement between the two investigators was good to very good, regardless of the number of counted cells (kappa values between 0.74 and 0.82). Cyclin B1 is a prognostic factor for breast cancer death in a population‐based node negative patient cohort which can identify high‐risk patients with a good to very good reproducibility.  相似文献   
103.
In the present study, the effects of acute and chronic morphine exposure on testosterone concentrations in the central nervous system (CNS) and serum were investigated in rats. Acute morphine administration (5 mg/kg, s.c.) reduced significantly testosterone levels in serum and spinal cord but not in the brain. Following chronic morphine administration (orally for 21 days), the brain testosterone was also significantly reduced as well as serum and spinal cord. Since, the decrease in testosterone levels following morphine exposure was more obvious in the CNS than serum, we suggested that it cannot be caused by only a direct decline in testosterone levels in periphery, and an increased local metabolism of testosterone in the CNS might be attributed in these effects. This hypothesis was supported with the findings that pretreatment with finasteride, a 5alpha-reductase inhibitor (5 mg/kg, s.c.) blocked testosterone elimination from the CNS following morphine exposure. Moreover, the serum concentration of 5alpha-reduced metabolites of testosterone, dihydrotestosterone and 3alpha-diol glucuronide was increased significantly following chronic morphine exposure, but not after co-treatment with finasteride. These results suggest that morphine exposure increase the CNS activity of 5alpha-reductase, which is an important metabolizing enzyme for testosterone.  相似文献   
104.
OBJECTIVE: To determine the sensitivity to an equal dose of ketamine/xylazine injection at anesthetic dose in a chronic model of hypernatremia. METHODS: This study was conducted at the Department of Physiology, Zanjan University of Medical Science, Zanjan, Iran in 2004. Sixty male Wistar rats, weighing 250 +/- 20 g were randomly allocated to 3 groups. The control group was provided with tap water, and first and second test groups consumed 1% and 2% salt concentrations for 144 hours. One hundred mg/kg ketamine and 10 mg/kg xylazine were used as an anesthetic agent. The measured anesthetic parameters comprises of righting reflex latency, required time for establishment of animal's immobility, immobility period, required time for appearance of animal's mobility and complete re-establishment of the righting reflex. RESULTS: The required time for inhibition of the righting reflex and animal's mobility in the second group was significantly shorter than the first and control groups. Immobility period, required time for appearance of animal's mobility and complete re-establishment of the righting reflex in the second group were significantly longer than the first and control groups. CONCLUSION: Hypernatremia increases the speed of transition from different steps of ketamine/xylazine anesthesia with significant delay in immobility period and recovery from anesthesia in rats, hence, anesthetic dose reduction in hypernatremia is necessary.  相似文献   
105.
In this paper, a microwave microscope is presented for characterization of skin abnormalities. A coplanar waveguide probe is designed and fabricated for high-resolution near-field imaging of the biological samples. Several simulations and measurement studies are described to present the capability of the proposed probe in identification of different tissues and the detection of fat masses at different depths. In addition, two methods are used to eliminate the measurement noise which is caused by non-targeted tissues. Then, the contours around the masses are obtained applying an edge detection method. The measurement results show that the proposed probe can detect the fat masses with amplitude contrast about 15 dB at a λ/10 (at 14.36 GHz) standoff distance. The proposed microscope is easy to fabricate, and provides a low-cost solution for fast and accurate skin cancer detection of abnormalities in human body such as early detection of small tumors in breast or skin cancers.  相似文献   
106.
INTRODUCTION: Despite long standing iodine supplementation in Iran the prevalence of goiter remains high in some areas. This may suggest that causes other than iodine deficiency, such as autoimmune thyroid diseases, should also be considered. We therefore assessed the prevalence of anti-thyroid antibodies in children living in an inland area in Iran and correlated these findings with prevalence of goiter within this region. METHODS: In a cross-sectional study, 1948 students were selected by multistage random cluster sampling from the 108 primary schools (age, 7-13 year-old) of the urban and rural areas of Semirom. After obtaining written consent from their parents, the children were examined by endocrinologists for goiter grading. Grade 2 goitrous children (108 cases) were compared with non-goitrous children (111 children as control group) for anti-thyroid antibodies. RESULTS: Overall, 36.7% of 1948 students had goiter. The mean urinary iodine excretion level was 1.49+/-0.7 micromol/L. This was within normal limits. Of 219 children studied, 4.3% presented with subclinical hypothyroidism, and 7.3% had positive anti-thyroid antibodies. There was non-significant difference of positive thyroperoxidase antibody (anti-TPO) (Odds Ratio= 3.2, p= 0.13) but significant difference of anti Tg between goitrous and non goitrous children (Odds Ratio: 5.6, 95% CI: 1.18-26.0, p: 0.015). CONCLUSION: This study suggests that autoimmunity may be one of the mechanisms responsible for goiter persistence after iodine replenishment in this iodine deficient region, but the role of other factors should also be considered.  相似文献   
107.
108.
The high incidence of neurological disorders in patients afflicted with acquired immunodeficiency syndrome (AIDS) may result from human immunodeficiency virus type 1 (HIV-1) induction of chemotactic signals and cytokines within the brain by virus-encoded gene products. Transforming growth factor beta1 (TGF-beta1) is an immunomodulator and potent chemotactic molecule present at elevated levels in HIV-1-infected patients, and its expression may thus be induced by viral trans-activating proteins such as Tat. In this report, a replication-defective herpes simplex virus (HSV)-1 tat gene transfer vector, dSTat, was used to transiently express HIV-1 Tat in glial cells in culture and following intracerebral inoculation in mouse brain in order to directly determine whether Tat can increase TGF-beta1 mRNA expression. dSTat infection of Vero cells transiently transfected by a panel of HIV-1 long terminal repeat deletion mutants linked to the bacterial chloramphenicol acetyltransferase reporter gene demonstrated that vector-expressed Tat activated the long terminal repeat in a trans-activation response element-dependent fashion independent of the HSV-mediated induction of the HIV-1 enhancer, or NF-kappaB domain. Northern blot analysis of human astrocytic glial U87-MG cells transfected by dSTat vector DNA resulted in a substantial increase in steady-state levels of TGF-beta1 mRNA. Furthermore, intracerebral inoculation of dSTat followed by Northern blot analysis of whole mouse brain RNA revealed an increase in levels of TGF-beta1 mRNA similar to that observed in cultured glial cells transfected by dSTat DNA. These results provided direct in vivo evidence for the involvement of HIV-1 Tat in activation of TGF-beta1 gene expression in brain. Tat-mediated stimulation of TGF-beta1 expression suggests a novel pathway by which HIV-1 may alter the expression of cytokines in the central nervous system, potentially contributing to the development of AIDS-associated neurological disease.  相似文献   
109.

Aims

Previous study has reported that triglycerides-glucose (TyG) index, a product of triglycerides and fasting plasma glucose (FPG), might be useful in the prediction of incident type 2 diabetes (T2D). We evaluated the ability of the TyG index compared to FPG and OGTT as possible diabetes predictor in nondiabetic first-degree relatives (FDRs) of patients with T2D.

Methods

A total of 1,488 FDRs without diabetes of consecutive patients with T2D 30–70 years old (361 men and 1,127 women) were examined and followed for a mean (SD) of 6.9 (1.7) years for diabetes incidence. We examined the incidence of diabetes across quartiles of the TyG index and plotted a receiver operating characteristic (ROC) curve to assess discrimination. At baseline and through follow-up, participants underwent a standard 75-g two-hour oral glucose tolerance test.

Results

During 10,124 person-years of follow-up, 41 men and 154 women developed T2D. Those in the top quartile of TyG index were 3.4 times more likely to develop T2D than those in the bottom quartile (odds ratio 3.36; 95 % CI 1.83, 6.19). On ROC curve analysis, a higher area under the ROC was found for FPG (76.2; 95 % CI 71.9, 80.6), 1-hPG (81.0, 95 % CI 77.2, 84.9) and 2-hPG (76.5; 95 % CI 72.3, 80.8) than for TyG index (65.1; 95 % CI 60.5, 69.7).

Conclusions

TyG index is predicted T2D in high-risk individuals in Iran but FPG, 1-hPG and 2-hPG appeared to be more robust predictor of T2D in our study population.
  相似文献   
110.
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