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Protein and nucleic acid levels from the ovaries of Hyalomma dromedarii Koch were determined during different stages of oogenesis. The concentrations of total protein, DNA, and RNA increased during oogenesis, reflecting the rapid developmental changes taking place in this tissue. Peak protein and DNA levels were reached in the fully fed females, whereas RNA level peaked slightly earlier. Ribosomal RNA (rRNA) was found to be composed of 27.0s, 17.0s, and 4.1s particles. The ratio of 27.0s to 17.0s varied within the developing ovary, yet the 27.0s/4.1s ratio remained constant. The nucleotides of total RNA and rRNA were determined, and the ratio of purine/pyrimidine equaled approximately 1 and remained unchanged during oogenesis.  相似文献   
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Colorectal cancer in Egypt   总被引:9,自引:0,他引:9  
PURPOSE: The aim of this study was to review the age distribution and pathology features of colorectal cancer in Egypt. METHODS: A seven-year review (retrospective in first six years, prospective in the seventh) of all colorectal adenocarcinoma patients (N = 177; 104 males; mean age, 46; range, 19–74 years) presented to the Department of Surgery, Ain Shams University, was performed. Data from three other major hospitals throughout the country were retrieved and compared with Ain Shams data. Retrospective data were retrieved from patients files and surgery and pathology records. Family history of colorectal cancer and other characteristic hereditary nonpolyposis colorectal cancer tumors was obtained prospectively in all patients. RESULTS: According to Ain Shams data, the disease had no predilection to a specific age group. Thirty-eight percent of the tumors occurred in patients aged less than 40 years, and only 15 percent of patients were aged above 60 years. None of the young patients fulfilled the Amsterdam criteria for hereditary nonpolyposis colorectal cancer. Seventy-five percent of tumors occurred in the left side, 3 percent were Dukes A, and 58 percent were Dukes C. Synchronous and metachronous tumors occurred in 2.8 and 4.5 percent of patients, respectively. Adenomas were present in 5.6 percent of patients and bilharziasis in 3.4 percent of resection specimens. Data from different centers were remarkably similar to Ain Shams results. CONCLUSION: Colorectal cancer in Egypt has no age predilection and more than one-third of tumors affects a young population. The high prevalence in young people can neither be explained on a hereditary basis nor can it be attributed to bilharziasis. The disease usually presents at an advanced stage, and predisposing adenomas are rare. Similarity of the data from different centers suggests that this is the picture of colorectal cancer typical of Egypt.  相似文献   
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Objective: The present study aimed to throw the light on the anti-osteoprotic mechanism of Cicer arietinum extract (CAE) seeds against ovariectomized (OVX) rats. Methods: Seventy female rats were divided into two groups. The first group (14 rats/group) represented normal rats (Sham operated) while the second group (56 rats/group) underwent bilateral ovariectomy (OVX). After one week of recovery from ovariectomy surgery, the second group was randomly subdivided into 4 subgroups (14 rats/ each subgroup). The rats administered orally; distilled water (vehicle) (1st subgroup), Cicer arietinum extract (CAE) (500 or 1000 mg/kg body weight/day) (2nd and 3rd subgroups), alendronate (6.5 mg/kg mg/kg body weight) as a positive control one time/week (4rh subgroup), daily for 10 weeks. Results: The present study demonstrated that ovariectomy caused significant decrease in bone mineral; density (BMD) and content (BMC), Bone-specific alkaline phosphatase (BALP), calcium (Ca), phosphorus (P), parathyroid hormone (PTH) and calcitonin levels. Furthermore, ovariectomy induced significant elevation of tartrate-resistant acid phosphatase 5b (TRAP 5b) and receptor activator of nuclear factor (NF-kappa β) ligand (RANKL) concentration. Conversely, osteoprotegerin (OPG) and OPG/RANKL ratio were decreased following ovariectomy. The present work suggests that CAE has antiosteoporotic action against ovariectomy effects and its activity may results from its phytochemical and/or phytoestrogen contents. Conclusion: The ongoing study speculates that the CAE exerts its action through regulation of RANK/RANKL/OPG system. As, CAE not only promotes osteoblast differentiation, but also up-regulates OPG and downregulates RANKL secretion in osteoblasts, subsequently prevents bone loss and osteoporosis.  相似文献   
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The aim of this study is to explore relationship between HLA-DRB1 alleles and the susceptibility and clinical features of rheumatoid arthritis (RA) in the south Tunisian population. We studied 142 RA patients and 123 controls matched for age, sex, and ethnicity. HLA-DRB1 genotyping and HLA-DRB1*04 subtypes were performed using polymerase chain reaction/sequence-specific primers. Association was assessed based on the χ (2) test and odds ratio with 95% confidence interval. For multiple comparisons, p value was corrected (p (c)) with Bonferroni test. Two alleles, HLA-DRB1*04 (p=0.045, p(c)=NS) and HLA-DRB1*10 (p=0.021, p(c)=NS), were found to have increased frequencies in RA patients compared to controls. In contrast HLA-DRB1*08 allele was found to have a decreased frequency in patients compared to controls (p=0.044, p(c)=NS). Molecular subtyping of the most prevalent allele (DRB1*04) revealed increased frequencies of HLA-DRB1*04:05 in patients compared to controls (p=0.013, p(c)=NS) whereas HLA-DRB1*04:02 showed a protective effect (p=0.005, p(c)=0.04). Moreover, stratified analyses indicated statistically significant associations between HLA-DRB1*04 allele and anti-cyclic peptides antibodies positivity (ACPA(+)) and rheumatoid factor positivity (RF(+); p(c)=0.03, for both subgroups), HLA-DRBI*10 and ACPA(+) and the presence of another autoimmune disease (p(c)=0.05 and p(c)=0.007, respectively), and HLA-DRB1*04:05 and RF(+) and erosion (p(c)=0.005 and p(c)=0.049; respectively). A significant decrease in the frequency of the DRB1*04:02 allele was observed in patients with ACPA(+) and RF(+) subgroups (p(c)=0.04 and p(c)=0.02, respectively). Our results showed that there was a trend of positive association of HLA-DRB1*04 and HLA-DRB1*10 with RA as such and significant associations with the disease severity in the south Tunisian population.  相似文献   
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3-Benzyl-2-((3-methoxybenzyl)thio)benzo[g]quinazolin-4(3H)-one was previously synthesized and proved by physicochemical analyses (HRMS, 1H and 13C NMR). The target compound was examined for its radioactivity and the results showed that benzo[g]quinazoline was successfully labeled with radioactive iodine using NBS via an electrophilic substitution reaction. The reaction parameters that affected the labeling yield such as concentration, pH and time were studied to optimize the labeling conditions. The radiochemical yield was 91.2?±?1.22% and the in vitro studies showed that the target compound was stable for up to 24?h. The thyroid was among the other organs in which the uptake of 125I-benzoquinazoline has increased significantly over the time up to 4.1%. The tumor uptake was 6.95%. Radiochemical and metabolic stability of the benzoquinazoline in vivo/in vitro and biodistribution studies provide some insights about the requirements for developing more potent radiopharmaceutical for targeting the tumor cells.  相似文献   
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In this work, we provide an up-to-date summary of the available molecular- and cell-related mechanisms by which alpha1-antitrypsin (AAT) protein could be of benefit in treating COVID-19 patients. As well, we demonstrate the current status in terms of the ongoing clinical trials using AAT in COVID-19 patients. Finally, we touch on the potential role gene therapy and stem cell-based gene therapy could have in such emerging and serious condition caused by the SARS-CoV-2 virus.  相似文献   
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OBJECTIVES: To audit the management of vascular trauma in Kuwait, 1992-2000. DESIGN: Retrospective open study. SETTING: Vascular surgery unit, teaching hospital, Kuwait. SUBJECTS: 155 patients with vascular injuries, most of which (n = 118) involved the extremities. 21 had neck injuries, 10 abdominal, and 6 chest. INTERVENTION: Revascularisation usually using the long saphenous vein in addition to direct repair or end-to-end anastomosis. MAIN OUTCOME: Morbidity (amputation) and mortality. RESULTS: Four lower limb grafts failed, two of which (2/69, 3%) required amputation. Overall, four patients died (3%), one of pulmonary embolism and 3 of severe injuries to major abdominal vessels. 3/10 patients with abdominal vascular trauma died. Mean (SD) follow up period was 4.4 (2) years. CONCLUSIONS: Civilian violence has increased in Kuwait. Vascular trauma to abdominal vessels is associated with high mortality. Autogenous saphenous vein forms an excellent conduit for revascularisation.  相似文献   
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