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11.

Background

Human induced pluripotent stem cells offer perspectives for cell therapy and research models for diseases. We applied this approach to the normal and pathological erythroid differentiation model by establishing induced pluripotent stem cells from normal and homozygous sickle cell disease donors.

Design and Methods

We addressed the question as to whether these cells can reach complete erythroid terminal maturation notably with a complete switch from fetal to adult hemoglobin. Sickle cell disease induced pluripotent stem cells were differentiated in vitro into red blood cells and characterized for their terminal maturation in terms of hemoglobin content, oxygen transport capacity, deformability, sickling and adherence. Nucleated erythroblast populations generated from normal and pathological induced pluripotent stem cells were then injected into non-obese diabetic severe combined immunodeficiency mice to follow the in vivo hemoglobin maturation.

Results

We observed that in vitro erythroid differentiation results in predominance of fetal hemoglobin which rescues the functionality of red blood cells in the pathological model of sickle cell disease. We observed, in vivo, the switch from fetal to adult hemoglobin after infusion of nucleated erythroid precursors derived from either normal or pathological induced pluripotent stem cells into mice.

Conclusions

These results demonstrate that human induced pluripotent stem cells: i) can achieve complete terminal erythroid maturation, in vitro in terms of nucleus expulsion and in vivo in terms of hemoglobin maturation; and ii) open the way to generation of functionally corrected red blood cells from sickle cell disease induced pluripotent stem cells, without any genetic modification or drug treatment.Key words: human induced pluripotent stem cells, terminal maturation, erythropoietic differentiation  相似文献   
12.
Journal of NeuroVirology - Multiple sclerosis (MS) is one of the common autoimmune diseases. The exact etiology of MS is still unclear, but recent studies have shown the possibility of infectious...  相似文献   
13.

Background

Cumulative evidence from epidemiological, preclinical and clinical studies suggests estrogens may have psychoprotective effects in schizophrenic patients. Selective Estrogen Receptor Modulators could have therapeutic benefits in schizophrenia for both sexes without being hazardous to gynecological tissues or having feminizing effects. Few studies have been conducted regarding the effects of raloxifene on postmenopausal women suffering from schizophrenia. We conducted this placebo-controlled trial to compare the add-on effect of raloxifene to risperidone versus risperidone with placebo.

Methods

This was an 8-week, parallel-group, placebo-controlled trial undertaken at two universities affiliated psychiatric Hospitals in Iran. Forty-six postmenopausal women with the definite diagnosis of schizophrenia were enrolled in the study. Patients received risperidone (6 mg/day in 3 divided doses) combined with either placebo (N = 23) or 120 mg/day of raloxifene (N = 23) for 8 weeks. Patients were assessed by a psychiatrist at baseline and at 2 and 8 weeks after the start of medical therapy. Efficacy was defined as the change from baseline to endpoint in score on Positive and Negative Syndrome Scale (PANSS).

Results

For PANSS scores, the main effect comparing two types of intervention was not significant [F (1, 48) = 1.77, p = 0.18]. For positive subscale scores, there was marginal significant interaction between intervention type and time [F (2, 47) = 2.93, p = 0.06] and there was substantial main effect for time [F (2, 47) = 24.39, p = 0.001] within both groups showing reduction in positive subscale scores across the three time periods. In addition, the main effect comparing two types of intervention was significant [F (1, 48) = 3.78, p = 0.02]. On the other hand, for negative subscale scores, the main effect comparing two types of intervention was not significant [F (1, 48) = 1.43, p = 0.23]. For general subscale scores, the main effect comparing two types of intervention was not significant [F (1, 48) = 0.03, p = 0.86].

Conclusions

According to our findings, raloxifene as an adjunctive treatment to risperidone was only superior in improvement of positive symptoms and it was not effective in treating negative and general psychopathology symptoms.

Trial registration

The trial was registered at the Iranian registry of clinical trials: IRCT201205131556N42  相似文献   
14.
The purpose of this study was to assess the effect of 810-nm (DMC Equipamentos, Sao Carlos, Brazil) continuous wave low-level laser therapy (LLLT) on the pain caused by orthodontic elastomeric separators. Thirty-seven orthodontic patients (12 male and 25 female, aged 11–32 years, mean age?=?24.97 years) participated in the study, including 20 subjects aged 18 years or more, and 17 under 18 years of age. Four elastomeric separators (Dentarum, Springen, Germany) were placed for the first permanent molars (distal and mesial), either for maxillary (22 patients) or mandibular (15 patients) arches; one quadrant was randomly selected and used as a placebo group (received no laser irradiation). After separator placement for each quadrant, patients received 10 doses (2 J/cm2, 100 mW, 20 s) of laser irradiation on the buccal side (at the cervical third of the roots), for distal and mesial of the second premolars and first permanent molars, as well as distal of second permanent molars (five doses). The same procedure was repeated for the lingual or palatal side (five doses). After 24 h, patients returned to the clinic and received another 10 doses of laser irradiation on the same quadrant. Postseparation pain level recorded on a 10-cm visual analog scale for both jaws immediately (hour?0), and after 6, 24, 30 h, as well as on days?3, 4, 5, 6, and 7. Significant differences in the pain perception (PP) were found between the laser and placebo groups at 6, 24, 30 h, and day?3 of the experiment (P?<?0.05). Friedman’s test of multiple comparisons revealed significant differences in the PP among various time intervals for laser (chi-square?=?173.407, P?=?0.000) and placebo (chi-square?=?184.712, P?=?0.000) groups. In both groups, pain was highest at 6 and 30 h after placing elastomeric separators. No gender differences were observed in both groups. More pain was recorded in the mandible (P?<?0.05) at 24 (laser group) and 30 h (both groups) after starting the experiment. The PP was significantly higher (P?<?0.05) for the group aged 18 years or more, only at days?3 [both groups] and 4 [laser group only] of the experiment. The 810-nm continuous wave LLLT significantly reduced the PP in the first 3 days after orthodontic separation. However, the mean postseparation PP in both groups was low and wide ranges of PP scores were observed.  相似文献   
15.
Gestational diabetes mellitus (GDM) is one of the most common complications in pregnancies. Evaluating other conditions, including intra uterine growth restriction and pre-eclampsia, some studies have shown significant changes in blood flow velocity of fetal middle cerebral artery (MCA). Our study is one of the few that has aimed to assess the effects of GDM on Doppler parameters of the fetal MCA and umbilical artery (UA) and to compare with normal pregnancies. This cross-sectional study was performed on 66 pregnant women, including 33 women with GDM and the others without it, in Akbar-Abadi University Hospital in Tehran, Iran during 2010–2011. Peak systolic and diastolic velocities, pulsatility index (PI), resistance index (RI) and systolic diastolic ratio (SD) were recorded in UA as well as both right and left fetal MCAs for every recruited pregnant women by means of Doppler ultrasonography. The mean gestational age at the time of examination was 34.45 (SD = 2.62) weeks in GDM group. Although all of the measured Doppler parameters had higher values in GDM pregnancies, the differences were not significant between two groups of study; except for the left fetal MCA-PI, which was significantly higher in GDM group [2.07 (SD = 0.07) vs. 1.85 (SD = 0.74), P = 0.03]. Our results show that gestational diabetes may contribute to an elevated PI in the fetal MCA. Although there is not yet strong proof for the effect of GDM on the fetal brain hemodynamics, the significant higher MCA-PI warrants more attention towards better controlling of the hyperglycemia during pregnancy.  相似文献   
16.
17.
Currently used xenograft models for prostate cancer bone metastasis lack the adequate tissue composition necessary to study the interactions between human prostate cancer cells and the human bone microenvironment. We introduce a tissue engineering approach to explore the interactions between human tumor cells and a humanized bone microenvironment. Scaffolds, seeded with human primary osteoblasts in conjunction with BMP7, were implanted into immunodeficient mice to form humanized tissue engineered bone constructs (hTEBCs) which consequently resulted in the generation of highly vascularized and viable humanized bone. At 12 weeks, PC3 and LNCaP cells were injected into the hTEBCs. Seven weeks later the mice were euthanized. Micro-CT, histology, TRAP, PTHrP and osteocalcin staining results reflected the different characteristics of the two cell lines regarding their phenotypic growth pattern within bone. Microvessel density, as assessed by vWF staining, showed that tumor vessel density was significantly higher in LNCaP injected hTEBC implants than in those injected with PC3 cells (p < 0.001). Interestingly, PC3 cells showed morphological features of epithelial and mesenchymal phenotypes suggesting a cellular plasticity within this microenvironment. Taken together, a highly reproducible humanized model was established which is successful in generating LNCaP and PC3 tumors within a complex humanized bone microenvironment. This model simulates the conditions seen clinically more closely than any other model described in the literature to date and hence represents a powerful experimental platform that can be used in future work to investigate specific biological questions relevant to bone metastasis.  相似文献   
18.
Open in a separate window OBJECTIVESLung volume reduction (LVR) is an efficient and approved treatment for selected emphysema patients. There is some evidence that repeated LVR surgery (LVRS) might be beneficial, but there are no current data on LVRS after unsuccessful bronchoscopic LVR (BLVR) with endobronchial valves (EBVs). We hypothesize good outcome of LVRS after BLVR with valves.METHODSIn this study, we retrospectively investigated all patients who underwent LVRS between 2015 and 2019 at 2 centres after previous unsuccessful EBV treatment. They were further divided into subgroups with patients who never achieved the intended improvement after BLVR (primary failure) and patients whose benefit was fading over time due to the natural development of emphysema (secondary failure). Patients with severe air leak after BLVR and immediate concomitant LVRS and fistula closure thereafter were analysed separately.RESULTSA total of 38 patients were included. Of these, 19 patients had primary failure, 15 secondary failure and 4 were treated as an emergency due to severe air leak. At 3 months after LVRS, forced expiratory volume in 1 s had improved significantly by 12.5% (P = 0.011) and there was no 90-day mortality. Considering subgroups, patients with primary failure after BLVR seem to profit more than those with secondary failure. Patients with severe air leak after BLVR did not profit from fistula closure with concomitant LVRS.CONCLUSIONSLVRS after previous BLVR with EBVs can provide significant clinical improvement with low morbidity, although results might not be as good as after primary LVRS.  相似文献   
19.
20.

Objectives

To describe the change in the incidence rates of primary and secondary focal segmental glomerulosclerosis (FSGS) from 1994 through 2013 in Olmsted County, Minnesota, and to identify the clinical and biopsy characteristics that distinguish primary from secondary FSGS.

Patients and Methods

Olmsted County adult residents with native kidney biopsy from January 1, 1994, through December 31, 2013, and FSGS as the only glomerulopathy were identified. The clinical and pathologic characterstics of primary and secondary FSGS were described and compared, and incidence rates were calculated.

Results

Of 370 adults biopsied, 281 had glomerular diseases, of which 46 (16%) had FSGS. From 1994-2003 to 2004-2013, there were significant increases in kidney biopsy rates (14.7 [95% CI, 12.1-17.3] vs 22.9 [95% CI, 20.0-25.7] per 100,000 person-years, 17% increase per 5 years; P<.001) and total FSGS rates (1.4 [95% CI, 0.6-2.2] vs 3.2 [95% CI, 2.1-4.3] per 100,000 person-years, 41% increase per 5 years; P=.02). Compared with patients with limited foot process effacement (<80%), patients with diffuse effacement (≥80%) without an identifiable cause had lower serum albumin levels (P<.001), had higher proteinuria (P<.001), and were more likely to have nephrotic syndrome (100% vs 4%; P<.001). Patients with diffuse effacement without an identifiable cause were classified as primary FSGS, which accounted for 3 of 12 patients (25%) during 1994-2003 and 9 of 34 (26%) during 2004-2013.

Conclusion

Although the incidence of FSGS has increased, the proportions of primary and secondary FSGS have remained stable.  相似文献   
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