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81.
A high incidence of skin cancers has been noted around the Semipalatinsk Nuclear Testing Site (SNTS) in Kazakhstan. Recently, basal cell carcinoma (BCC) susceptibility genes, human homolog of the Drosophila pathed gene (PTCH), and the xeroderma pigmentosa group A-complementing gene (XPA), have been cloned and localized on chromosome 9q22.3. To clarify the effect of low-dose irradiation on the occurrence of BCC, we used microdissection and polymerase chain reaction to identify loss of heterozygosity (LOH) at 9q22.3 using BCC samples obtained from this region. Ten Japanese samples were analyzed as controls. LOH with at least 1 marker was identified in 5 of 14 cases from around SNTS, whereas only 1 case with 1 marker was identified among the 10 Nagasaki cases. The total number of LOH alleles from SNTS (8 of 45) was significantly higher than the number from Nagasaki (1 of 26) (P = 0.03). The higher incidence of LOH on 9q22.3 in BCC from around SNTS suggests involvement of chronic low-dose irradiation by fallout from the test site as a factor in the cancers.  相似文献   
82.
Reprogramming of adult human somatic cells to induced pluripotent stem cells (iPSCs) is a novel approach to produce patient-specific cells for autologous transplantation. Whether such cells survive long-term, differentiate to functional neurons, and induce recovery in the stroke-injured brain are unclear. We have transplanted long-term self-renewing neuroepithelial-like stem cells, generated from adult human fibroblast-derived iPSCs, into the stroke-damaged mouse and rat striatum or cortex. Recovery of forepaw movements was observed already at 1 week after transplantation. Improvement was most likely not due to neuronal replacement but was associated with increased vascular endothelial growth factor levels, probably enhancing endogenous plasticity. Transplanted cells stopped proliferating, could survive without forming tumors for at least 4 months, and differentiated to morphologically mature neurons of different subtypes. Neurons in intrastriatal grafts sent axonal projections to the globus pallidus. Grafted cells exhibited electrophysiological properties of mature neurons and received synaptic input from host neurons. Our study provides the first evidence that transplantation of human iPSC-derived cells is a safe and efficient approach to promote recovery after stroke and can be used to supply the injured brain with new neurons for replacement.  相似文献   
83.
We recently reported a gene encoding the human CDw108, a glycosylphosphatidylinositol (GPI)-anchored membrane glycoprotein that is preferentially expressed on activated T lymphocytes and erythrocytes. The present study investigated the expression of CDw108 on various tissues and cells, particularly on T cells during development. The murine CDw108 cDNA was cloned initially, and it was highly homologous to the human CDw108 (88.0% or 89.3% similarity at the nucleotide or amino acid level, respectively) or identical to the murine semaphorin K1/Sema7A. The CDw108 mRNA was demonstrated in a few tissues including thymus and brain with the highest expression coming on day 7 in whole embryo followed by relatively consistent expression during development. Cell-surface expression of the CDw108 during T-cell development was further examined by flow cytometry in the human umbilical cord blood and thymus. It was preferentially expressed on a CD34+ stem cell population of umbilical cord blood, and CD3dull CD34+/- CD117 (c-kit)+ CD4bright CDbright cells in the thymus that are involved in the stage of positive selection. These results suggest the contribution of CDw108 in T-cell development, especially in the stage of positive selection in the thymus.  相似文献   
84.
Mesh surgeries, such as sacrocolpopexy and transvaginal mesh surgery, are commonly used to treat pelvic organ prolapse. Although mesh surgeries have a high success rate, they are unsuitable for some patients. For a patient with pelvic organ prolapse and highly calcified multiple fibroids, we performed hybrid sacrocolpopexy combined with transvaginal mesh surgery with a method modified for the patient's condition. Three months after surgery, the results were highly satisfactory. This approach is simple, secure, and versatile for patients who are not good candidates for conventional mesh surgeries. This novel hybrid mesh surgery is an option for treating various types of pelvic organ prolapse.  相似文献   
85.
OBJECTIVE: To assess early atherosclerosis using B-mode imaging of the carotid artery in children and adolescents with type 1 diabetes mellitus (T1DM) and to evaluate the relationship between various risk factors and intimal plus medial thickness (IMT) in this population. METHODS: Fifty-two children and adolescents (aged 3-18 years) with uncomplicated T1DM and 43 age- and gender-matched healthy controls were examined. B-mode imaging was used to determine the intimal plus medial thickness (IMT) of the carotid artery in all subjects. Patients with T1DM and control subjects were divided into two groups according to age and gender. Furthermore, duration of DM was considered for comparison. RESULTS: Patients and control subjects showed no association between IMT and sex, systolic blood pressure (sBP), diastolic blood pressure (dBP), serum lipid levels or left ventricular ejection fraction (LVEF). However, statistical analysis indicated a good correlation between age and carotid arterial wall thickness in both diabetic and control groups. These findings were consistent with those in the literature. No correlation was found between IMT and the duration of DM. CONCLUSIONS: This study indicates that there is no association between T1DM and IMT in children and adolescents with T1DM.  相似文献   
86.
In predicting the aggressive behavior of bladder tumors, the histopathological characteristics of grade and invasive stage are of principal importance. However, for predicting tumor recurrence and progression, these are sufficient only to a limited extent, particularly in the case of superficial (pTa and pT1) urothelial cell carcinomas. New prognostic factors are therefore needed to avoid either insufficient or excessive treatment. In this retrospective study, we investigated the prognostic value of the p53 and Ki-67 immunoreactivity indices. The present study included 118 superficial urinary bladder tumors consisting of 58 recurrent and 60 non-recurrent cases. Twenty of the recurrent tumors progressed into a higher grade and/or invasive stage. Paraffin immunohistochemical analysis was carried out using anti-p53 and anti-Ki-67 antibodies on the initial tumor tissues. We concluded that there is a highly significant relationship between the p53 and Ki-67 immunoreactivities and the histological grade and pathological stage of the tumors (P < 0.0001). We observed a significant relationship between the presence of recurrence and progression and the p53 immunoreactivity index (P < 0.01 and P = 0.017, respectively) and Ki-67 immunoreactivity index (P < 0.0001 and P = 0.046, respectively). Positivity for p53 and Ki-67 can demonstrate the risk of recurrence (p53: sensitivity = 76%, specificity = 58%; Ki-67: sensitivity = 86%, specificity = 48%) and progression (p53: sensitivity = 80%, specificity = 46%; Ki-67: sensitivity = 85%, specificity = 36%; ). We believe that both of these immunohistochemical markers can be considered valuable in addition to classical histopathological prognostic parameters for predicting recurrence and progression risks.  相似文献   
87.
目的 评价利培酮治疗精神分裂症的疗效和副作用。方法 将 5 9例精神分裂症住院病人随机分为利培酮 ( 4 mg/d)1组 ( 1 9例 )、利培酮 ( 6 mg/d) 2组 ( 2 0例 )和氯丙嗪组 ( 2 0例 ) ,治疗 8周。用阳性与阴性症状量表 ( PANSS)评定疗效 ,用副反应量表 ( BPRS)及锥体外系副反应量表 ( TESS)评定副反应。结果 利培酮两个剂量组与氯丙嗪组之间疗效无显著性差异。在认知因子、阴性因子、PANSS总分减分率方面 ,利培酮组与氯丙嗪组有显著性差异。利培酮的副反应有锥体外系反应、失眠、头昏等。结论 利培酮是一种安全有效的抗精神病药物 ,在改善认知功能和阴性症状方面 ,利培酮优于氯丙嗪 ,少数病例可出现锥体外系反应。  相似文献   
88.
The regulation of glucose, lipid metabolism and immunoreactivities of insulin and glucagon peptides by delta-9-tetrahydrocannabinol (Δ9-THC) in diabetes were examined in an experimental rat model. Male Sprague-Dawley rats were divided into four groups: (1) control, (2) Δ9-THC treated, (3) diabetic, and (4) diabetic + Δ9-THC. The type 2 diabetic rat model was established by intraperitoneal (i.p.) injection of nicotinamide (85 mg/kg body weight) followed after 15 min by i.p. injection of streptozotocin (STZ) at 65 mg/kg of body weight. Δ9-THC and Δ9-THC treated diabetic groups received 3 mg/kg/day of Δ9-THC for 7 days. The immunolocalization of insulin and glucagon peptides was investigated in the pancreas using a streptavidin–biotin–peroxidase technique. High density lipoprotein cholesterol (HDL), low density lipoprotein cholesterol (LDL), very low density lipoprotein cholesterol (VLDL), triglycerides (TG), total cholesterol (TC) and total protein (TP) levels were measured in serum. Total islet area percent of insulin immunoreactive cells slightly changed in diabetic + Δ9-THC rats compared to diabetic animals. However, the area percent of glucagon immunoreactive cells showed a decrease in diabetic + Δ9-THC rats compared to that of diabetic animals alone. Serum TC, HDL and LDL levels of diabetes + Δ9-THC group showed a decrease compared to the diabetic group. These results indicate that Δ9-THC may serve a protective role against hyperlipidemia and hyperglycemia in diabetic rats.  相似文献   
89.
Dried blood spots (DBS) collected onto filter paper have eased the difficulty of blood collection in resource-limited settings. Currently, Whatman 903 (W-903) filter paper is the only filter paper that has been used for HIV load and HIV drug resistance (HIVDR) testing. We therefore evaluated two additional commercially available filter papers, Ahlstrom grade 226 (A-226) and Munktell TFN (M-TFN), for viral load (VL) testing and HIVDR genotyping using W-903 filter paper as a comparison group. DBS specimens were generated from 344 adult patients on antiretroviral therapy (ART) in Botswana. The VL was measured with NucliSENS EasyQ HIV-1 v2.0, and genotyping was performed for those specimens with a detectable VL (≥2.90 log10 copies/ml) using an in-house method. Bland-Altman analysis revealed a strong concordance in quantitative VL analysis between W-903 and A-226 (bias = −0.034 ± 0.246 log10 copies/ml [mean difference ± standard deviation]) and W-903 and M-TFN (bias = −0.028 ± 0.186 log10 copies/ml) filter papers, while qualitative VL analysis for virological failure determination, defined as a VL of ≥3.00 log10 copies/ml, showed low sensitivities for A-266 (71.54%) and M-TFN (65.71%) filter papers compared to W-903 filter paper. DBS collected on M-TFN filter paper had the highest genotyping efficiency (100%) compared to W-903 and A-226 filter papers (91.7%) and appeared more sensitive in detecting major HIVDR mutations. DBS collected on A-226 and M-TFN filter papers performed similarly to DBS collected on W-903 filter paper for quantitative VL analysis and HIVDR detection. Together, the encouraging genotyping results and the variability observed in determining virological failure from this small pilot study warrant further investigation of A-226 and M-TFN filter papers as specimen collection devices for HIVDR monitoring surveys.  相似文献   
90.
We treated a 73-year-old man who developed a pyothorax-associated pleural lymphoma after a 52-year history of tuberculous pleuritis. The lymphoma was classified histologically as a diffuse large, B-cell type. Epstein-Barr virus (EBV) was identified in the tumor by immunocytochemical and molecular methods. Chemotherapy both without and with the addition of rituximab was only minimally effective, but adding radiotherapy to chemotherapy reduced the tumor size, resulting in a partial remission. The EBV load measured by a quantitative real-time polymerase chain reaction correlated well with the tumor size and the serum lactate dehydrogenase concentration. Monitoring the EBV load may be useful in the management of pyothorax-associated lymphoma.  相似文献   
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