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41.
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Hyperphosphatemia has been associated with the development of secondary hyperparathyroidism, renal osteodystrophy, cardiovascular calcification and increased risk of death. Using a one group, pretest-posttest study design, we sought to evaluate changes in serum phosphorus, calcium, parathyroid hormone and subject knowledge in response to a 3-month educational intervention. Mean serum phosphorus levels did not differ significantly between the three evaluation periods: pretreatment (5.69 mg/dl), treatment (5.84 mg/dl) and posttreatment (6.17 mg/dl). Mean serum calcium, calcium-phosphorus product and PTH values also did not differ significantly between the treatment periods. We observed no difference between the subject test scores between the two testing periods. Calcium-phosphorus product, serum phosphorus and PTH values on average, despite the education program, remained outside the K/DOQI target guidelines 44, 56 and 81% of the time, respectively. The results of this study suggest that an aggressive 3-month patient education program targeting dietary phosphorus knowledge, phosphate binder name and dosing, and knowledge of medical consequences associated with non-compliance had no effect on the serum phosphorus, calcium, PTH or phosphate binder need.  相似文献   
43.
Apolipoprotein D (apoD) is elevated in Alzheimer's disease (AD) cortex, localizing to cells, blood vessels, and neuropil deposits (plaques). The role of apoD in AD pathology and the extent of its co-distribution with diffuse (amorphous) and compact (dense fibrillar) amyloid-beta (Abeta) plaques are currently unclear. To address this issue, we combined apoD and Abeta immunohistochemistry with ThioS/X-34 staining of the beta-pleated sheet protein conformation in temporal cortex from 36 AD patients and 12 non-demented controls. ApoD-immunoreactive, Abeta-immunoreactive, and ThioS/X-34-stained plaques were detected exclusively in AD tissue. Dual-immunolabeling showed that 63% of Abeta plaques co-localized apoD. All apoD plaques contained Abeta protein and ThioS/X-34 fluorescence. Compared to controls, AD cases showed elevated vascular and intracellular apoD immunostaining which localized primarily to cells clustered within plaques and around large blood vessels. ApoD-immunoreactive cells within plaques morphologically matched MHC-II- and CD-68-immunoreactive microglia, and did not contain the astrocytic marker GFAP, which labeled a subset of apoD-immunoreactive cells surrounding plaques. These data suggest that neuropil deposits of apoD localize only to a subset of Abeta plaques, which contain compact aggregates of fibrillar Abeta. Elevated apoD in AD brain may influence Abeta aggregation, or facilitate phagocytosis and transport of Abeta fibrils from plaques to cerebral vasculature.  相似文献   
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BACKGROUND: Our objective was to develop a new animal model for the study of polycystic ovaries by using the non-steroidal aromatase inhibitor, letrozole. METHODS: Thirty four rats were divided into four groups, including a control group of 10 rats that received vehicle only (1% aqueous solution of carboxmethlycellulose [CMC]) once daily orally (p.o.) and three treatment groups of eight rats each that were administered letrozole at concentrations of 0.1 or 0.5 or 1 mg/kg p.o. dissolved in 1% CMC (2 mL/kg) once daily. The treatment period was 21 days. During this period, vaginal smears were collected daily for estrus cycle determination. On the day subsequent to last letrozole dose administration, rats were killed; uteri and ovaries were then excised and weighed. Serum hormone levels and histologic changes in ovaries were examined. RESULTS: When compared to control group, ovaries from study groups showed high incidence of subcapsular ovarian cyst and capsular thickening together with incomplete luteinization and decreased number of corpora lutea. Letrozole treatment brought about dose-dependent suppression of uterine weight despite having no significant effect on ovarian weight. Although serum estradiol and progesterone levels were reduced in a dose-dependent manner, testosterone levels were elevated as were levels of luteinizing hormone (LH). Serum follicle-stimulating hormone (FSH) levels were markedly increased at higher doses of letrozole (0.5 and 1.0 mg/kg), contrary to low dose of letrozole (0.1 mg/kg) at which slight decrease was observed. CONCLUSIONS: Despite the fact that this is not a fully convincing model for the study of polycystic ovaries or of polycystic ovary syndrome (PCOS) as a whole, this animal model in several ways is similar to the human polycystic ovary syndrome.  相似文献   
46.
PURPOSE: Taurolidine is a broad spectrum, non-antibiotic antimicrobial agent, not previously tested against infectious endophthalmitis. The efficacy of intravitreal taurolidine in the treatment of experimental Staphylococcus epidermidis endophthalmitis was evaluated and compared with vancomycin in a rabbit model. METHODS: The right eyes of 34 albino rabbits were infected with an intravitreal inoculum of S. epidermidis (10(5) colony-forming units/0.1 ml). The right eyes of four rabbits (group 7) were not infected and served as uninfected controls. 24 hours after inoculation of bacteria the animals were divided into the following treatment groups: group 1 (7 rabbits) received intravitreal taurolidine at 24 hours and group 2 (7 rabbits) received at 48 hours. Group 3 (7 rabbits) received vancomycin at 24 hours and group 4 (7 rabbits) at 48 hours. Group 5 (3 rabbits) received polyvinylpyrrolidone at 24 hours and group 6 (3 rabbits) at 48 hours. Clinical scoring was performed at 24, 48 and 72 hours. At 72 hours post inoculation, vitreous samples were collected for quantitative microbiological studies and then, the eyes were enucleated for histopathological scorings. RESULTS: The clinical and histopathological examinations revealed significant amelioration of inflammation in eyes treated with taurolidine and vancomycin when compared with polyvinylpyrrolidone. The eyes treated with taurolidine also had significantly lower colony forming units than the eyes treated with polyvinylpyrrolidone and taurolidine rendered many eyes sterile. CONCLUSION: Taurolidine is expected to be a potential agent for treatment of S. epidermidis endophthalmitis.  相似文献   
47.
We have found the intramedullary supracondylar femoral nail to be useful in special situations involving the tibia: proximal tibial fractures and nonunions, intercalary resections for tumors in the proximal or distal tibial diaphysis, and tibio-talo-calcaneal arthrodeses. We report on ten such cases.
Résumé Nous avons trouvé que le clou centromédullaire supracondylien fémoral pouvait être utile dans des situations particulières au niveau du tibia: les fractures et pseudarthroses proximales tibiales, les résections intercalaires pour tumeurs diaphysaires tibiales proximales ou distales et les arthrodèses tibio-astragalo-calcanéennes. Nous rapportons 10 cas illustrant ces situations.
  相似文献   
48.
The environmental exposure to heavy metals is a well-known risk factor for cancer. We investigated levels of seven different heavy metals, (Co, Cd, Pb, Zn, Mn, Ni and Cu) in soil, fruit and vegetable samples of Van region in Eastern Turkey where upper gastrointestinal (GI) cancers are endemic. Heavy metal contents of the samples were determined by flame atomic absorption spectrometer. Four heavy metals (Cd, Pb, Cu and Co) were present in 2- to 50-fold higher concentrations whereas zinc levels were present in 40-fold lower concentrations in soil. The fruit and vegetable samples were found to contain 3.5- to 340-fold higher amounts of the six heavy metals (Co, Cd, Pb, Mn, Ni and Cu) tested. The volcanic soil, fruit and vegetable samples contain potentially carcinogenic heavy metals in such a high levels that these elements could be related to the high prevalence of upper GI cancer rates in Van region.  相似文献   
49.
Massive structural allograft in revision of septic hip arthroplasty   总被引:1,自引:0,他引:1  
We reviewed 10 patients who had undergone two-stage reconstruction with massive structural allografts following failure of hip arthroplasty due to infection. The mean follow-up time was more than 5 years (range 3-10 years). There was no case of the infection recurring. The most common pathogen isolated at the time of first-stage surgery was Stalphylococcus epidermnidis. The mean preoperative modified Harris Hip score was 27.4 (range 9-58) and the mean postoperative score was 73.5 (range 53-92) with a mean increase in the score of 46.1 points. One patient required revision of the acetabular cup for aseptic loosening and another had a dislocation, which was stable after manual reduction. We conclude that the use of a massive structural allograft in revision of septic hip arthroplasty is a viable option.  相似文献   
50.
Monoclonal antibodies (mAbs) have been used to treat malignancies in humans with varying degrees of success. Progress has been hindered by the lack of suitable animal models, which would ideally consist of immunocompetent animals that are tolerant to tumor-associated antigens. Suitable models would allow the study and optimization of anti-tumor immunotherapy. We describe a murine model for the study of immunotherapy in colorectal cancers. Carcinoembryonic antigen (CEA) is a cell-surface glycoprotein that is expressed on normal human intestinal epithelium and that is overexpressed in intestinal tumors. Mice that are transgenic for the human CEA gene (CEA.Tg) were crossed with multiple intestinal neoplasia (MIN) mice. MIN mice carry a germline APC mutation and are prone to the development of intestinal adenomas. The offspring from the MIN x CEA.Tg cross developed intestinal adenomas that were shown by immunohistochemistry to overexpress CEA. Pharmacokinetic studies by using (125)I-labeled anti-CEA mAb PR1A3 showed rapid localization of antibody to tissues expressing CEA, especially the gastrointestinal tract. Macroscopic and microscopic radioautographic analysis of the gastrointestinal tracts from MIN/CEA.Tg mice indicated that PR1A3 targeted and was retained in tumors at levels higher than in areas of normal gut. These results demonstrate the utility of the MIN/CEA.Tg mouse as a model for the study of anti-CEA immunotherapy and, furthermore, demonstrate the efficiency of tumor localization by PR1A3.  相似文献   
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