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101.
To determine the prevalence of helminthic infections in Pursat Province, Cambodia, we tested fecal specimens from 471 children, 10-14 years of age, in June 2007. The prevalence of infection with echinostome flukes ranged from 7.5% to 22.4% in 4 schools surveyed. Adult worms were identified as Echinostoma revolutum.  相似文献   
102.
AIM: To observe the characteristics of iridociliary cysts in myopic patients and evaluate the influences on the position and safety of implantable collamer lens (ICL) after surgery.METHODS: Totally 270 eyes of 135 patients who underwent ICL surgery for the correction of myopia were included in this study. We observed preoperative and postoperative morphology of iridociliary cysts in ultrasonic biomicroscopy (UBM) image.RESULTS: A total of 138 iridociliary cysts were found in 88 eyes of 50 patients among 270 eyes of 135 patients before surgery (37%). Twenty-five patients had cysts in one eye (50%) and 25 had cysts in both eyes (50%). The prevalence of iridociliary cysts was negatively correlated with age, but no gender difference (P>0.05). The incidence of iridociliary cysts was much less in eyes with myopia greater than -9.00 D (P<0.05). The diameter of the largest cyst was 1.96 mm and the smallest cyst was 0.24 mm, with a majority within the range of 0.5 to 1.0 mm. Most of the cysts were located in the inferior temporal quadrant. One year after ICL implantation, 51 iridociliary cysts (37%) remained unchanged, 47 cysts (34%) decreased in size, and 40 cysts (29%) disappeared. Most of cysts that changed after surgery were smaller than 1.0 mm (P<0.05) and located in the nasal and temporal sides around the haptics of implantable lens. All the implantable lens were in their original position.CONCLUSION: Iridociliary cysts are commonly seen in myopic eyes. The cysts have no impact on the safety of ICL surgery. Some cysts may decrease in size or disappear after ICL implantation.  相似文献   
103.

Background

Several studies have suggested that primary tumor removal improved overall survival for patients with stage IV breast cancer. However, the survival benefit of local treatment remains controversial. The purpose of the present study was to determine whether surgical removal of the primary tumor provides survival benefits to patients with stage IV breast cancer.

Patients and Methods

We retrospectively reviewed the medical records of 155 patients with an initial diagnosis of stage IV breast cancer at Seoul National University Bundang Hospital from 2003 to 2014. Kaplan-Meier analysis was used to estimate the median survival. The log-rank test was used to compare differences in patient and tumor characteristics. Multivariate Cox regression analysis for survival was used, controlling for potential confounding variables.

Results

Of 155 patients with stage IV breast cancer, 95 (61%) underwent surgical removal of the primary tumor. The median follow-up period was 59 months (95% confidence interval [CI], 45-73 months). The median survival was longer for the patients with a better response to chemotherapy (70 vs. 47 months; P = .010) and for those who had undergone surgery (118 vs. 28 months; P < .001) than for those who without a better chemotherapy response or surgery. The median survival of the patients who received radiotherapy was better than that of the patients who did not (65 vs. 39 months; P = .004). Patients with luminal A cancer had a median survival of 118 months, the longest compared with those with other subtypes (P = .001). In addition, patients with distant metastasis at a single site had a longer median survival than did those with multiple metastatic sites. The multivariate Cox regression analysis revealed that fewer distant metastases, surgery of the primary tumor, a better response to chemotherapy, and luminal A subtype were significant independent predictors of survival.

Conclusion

Our results showed that primary tumor removal was independently associated with improvement in survival. Therefore, surgical management for the primary tumor could be considered more actively in patients with stage IV breast cancer.  相似文献   
104.
Berberine is an isoquinoline plant alkaloid with a long history of being used for the treatment of many diseases in Chinese herbal medicine. Berberine has a wide range of biochemical and pharmacological effects, including antitumor activities, but its mechanism of action is not clearly understood. In this study, we investigated that the relationship between the antiproliferative activities of berberine and the apoptotic pathway associated with its molecular mechanism of action in human glioblastoma T98G cells. Berberine treatment of T98G cell lines inhibited cell proliferation and induced cell death in a dose (50-200 microg/ml) dependent manner with an IC50 value of 134 microg/ml, which was associated with an increase in G1 arrest. Western blot analysis showed that the berberine-induced G1 arrest was mediated through the increased expression of P27 and the decreased expression of cyclin-dependent kinase (CDK) 2, CDK4, cyclin D, and cyclin E proteins. Berberine treatment also markedly enhanced apoptosis in T98G cells through the induction of a higher ratio of the Bax/Bcl-2 proteins, the disruption of mitochondrial membrane potential, and the activation of procaspase-9, caspase-9, caspase-3, and poly(ADP-ribose) polymerase (PARP). Berberine can inhibit T98G cell proliferation by inducing G1 arrest and apoptosis. These results demonstrate that the berberine-induced apoptosis of T98G cells is primarily mediated through the mitochondrial/caspases-dependent pathway.  相似文献   
105.
Objective: Many studies have shown that melatonin (MLT) has an anti-genotoxic effect in various tissues and cell lines. The aim of this study was to investigate the anti-genotoxic effect of MLT on normal human peripheral lymphocytes by assessing sister chromatid exchange (SCE) in vitro and in vivo. Materials and methods: Cells were treated with 50 and 200?μM of MLT. The human volunteers (n?=?20) for the in vivo study were administered a single dose of 3?mg MLT daily for 2 weeks. After sufficient time for its clearance, 1.5?mg of MLT daily was then administered to the same volunteers at same the period. Results: Our results demonstrated the anti-genotoxic effect of MLT in human blood lymphocyte in vitro and in vivo. In vitro, hypoxia increased the SCE frequency compared to the control and both doses of MLT significantly decreased the SCE frequency in the hypoxic cells (p?<?0.001). In vivo, oral administration of 3?mg MLT significantly increased the frequency of SCE, yet a small increase of SCE by hypoxia was found. Oral administration of 1.5?mg MLT showed no DNA damage but it had an anti-genotoxic effect. Discussion and conclusion: MLT may prove useful for reducing the genotoxic effects of hypoxia in peripheral lymphocytes and suggest its possible role for ischemic diseases.  相似文献   
106.
Primo-vessels have been observed in the rat abdominal cavity as floating thread like structures on and not adhering to fascia-wrapped internal organs. To date their presence, locations, and lengths have been irregular and unpredictable, and their identification not regularly repeatable, thus they have remained a nagging enigma in primo-vascular system research for several years. In this work, locations were found where primo-vessels were regularly present and observed repeatedly. These vessels were not floating or freely movable but lay in a regular position in the mesentery in the abdominal cavity of the rat, being observed between the cecum and small intestine and between the colon and mesentery root. The difference between a lymph vessel and a primo-vessel is described in anatomical and histological aspects. In addition, trypan blue was found to enter primo-vessels through the surrounding membranes and filled spaces between fibers comprising the primo-vessels. It is conjectured that the previously observed floating primo-vessels had anomalously and irregularly emerged, for some unknown physiological reasons, from primo-vessels normally located in the fascia-like mesentery.  相似文献   
107.
Objectives  We investigated the association of genetic polymorphisms of NQO1, ALDH2, CYP2E1, and the combined genotype of these genes on lung cancer risk, and also evaluated the association after stratification by cumulative smoking amounts and alcohol drinking levels. Methods  The case–control study was performed in 387 lung cancer patients and 387 age- and sex-matched cancer-free controls. Direct interview was conducted and the genotypes of NQO1, ALDH2, and CYP2E1 were investigated using PCR-RFLP or 5′-nuclease activity assay. Results  The proportion of individuals with occupational history of mining was significantly higher in cases than in controls. The risk of lung cancer was significantly lower in light-drinkers (<108 g/week) than non-drinkers. The NQO1 Pro/Ser + Ser/Ser genotype showed an increased risk for lung cancer with a marginal significance (OR = 1.35, 95% CI = 0.99–1.86) compared with NQO1 Pro/Pro genotype. In heavy-smokers, the combination of NQO1 Pro/Ser + Ser/Ser and CYP2E1 c1/c1 genotype was associated with a significantly increased risk for lung cancer (OR = 2.25, 95% CI = 1.14–4.43) compared with those of NQO1 Pro/Pro and CYP2E1 c1/c2 + c2/c2 genotype. We found a significant interaction between alcohol drinking level and the CYP2E1 genotype (P = 0.0227). Conclusions  Our result suggests that the risk of lung cancer is affected by smoking, alcohol drinking, and the genetic polymorphism of NQO1. In particular, genetic polymorphisms for NQO1, CYP2E1, and ALDH2 synergistically with cumulative smoking amounts and alcohol drinking levels interact in the carcinogenesis of lung cancer in Koreans.  相似文献   
108.
109.
Recent toxicity studies of zinc oxide nanoparticles by oral administration showed relatively low toxicity, which may be resulted from low bioavailability. So, the intrinsic toxicity of zinc oxide nanoparticles needs to be evaluated in the target organs by intravenous injection for full systemic concentration of the administered dosage. Although the exposure chance of injection route is low compared to oral and/or inhalation route, it is important to see the toxicity with different exposure routes to get better risk management tool. In this study, the effects of zinc oxide nanoparticles on dams and fetuses were investigated in rats after intravenous injection (5, 10, and 20 mg/kg) from gestation day 6 to 20. Two of 20 dams in the 20 mg/kg treatment group died during the treatment period. Hematological examination and serum biochemistry showed dose-dependent toxicity in treated dams. Histopathological analysis of treated dams revealed multifocal mixed cell infiltration and thrombosis in lung, tubular dilation in kidneys, and extramedullary hemopoiesis in liver. Total dead fetuses (post-implantation loss) were increased and the body weight of fetus was decreased in the 20 mg/kg treatment group. Statistical differences in corpora lutea, resorption, placental weight, morphological alterations including external, visceral and skeletal malformations were not observed in treated groups. Based on the data, lowest observed adverse effect level of injection route was suggested to be 5 mg/kg in dams and no observed adverse effect level was suggested to be 10 mg/kg in fetal developmental toxicity.  相似文献   
110.
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