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991.
BACKGROUND: Hematogenous metastasis occurs when cancer cells released from the primary site enter blood vessels and are transported to distant organs, where they attach and proliferate. Angiogenesis is essential for tumor growth and metastasis and depends on the production of angiogenic factors by tumor cells. METHODS: We analyzed data on 1184 Japanese adult men and women with gastric cancer with respect to the relation between vascular invasion and the potential for tumor angiogenesis and metastasis. All these patients were treated from 1976 to 1995 in the Department of Surgery II, Kyushu University. In 300 patients, the expression of vascular endothelial growth factor (VEGF) and p53 protein in tumor tissues was examined by using an immunohistochemical staining method or Northern blotting or both. Intratumoral microvessels were stained with anti-CD31 monoclonal antibody. RESULTS: Vascular invasion was evident in 254 patients (21.5%), and in these patients lymphatic invasion was more frequent and the rate of lymph node metastasis was higher in relation to the extent of vascular invasion. The positive findings were directly related to the depth of invasion and the presence of lymph node and liver metastasis. Tumor invasive and metastatic rates increased in relation to the extent of vascular invasion. Expressions of VEGF and p53 protein were higher and microvessel density was more prominent in tumor tissues in relation to the extent of vascular invasion. A close relation between VEGF and p53 protein expressions was also noted in tumors that showed vascular invasion. The expression of VEGF is one of the independent risk factors for vascular invasion. The postoperative outcome was poorer in patients with vascular invasion in relation to the extent of vascular invasion. CONCLUSIONS: Our findings show that gastric cancers with characteristics of vascular invasion have greater intratumoral angiogenesis and that VEGF and p53 overexpression is associated with intratumoral angiogenesis and metastases to distant organs.  相似文献   
992.
Outcome of surgery in cystic renal cell carcinoma   总被引:30,自引:0,他引:30  
OBJECTIVES: To review cases of cystic renal cell carcinoma treated surgically at our institution and define their clinical and histopathologic features. METHODS: Between 1986 and 1998, 21 patients with cystic renal cell carcinoma were treated surgically. Cystic renal cell carcinoma was categorized using Hartman's classification. RESULTS: Histopathologic examination demonstrated cystic necrosis in 11 patients, multilocular cystic renal cell carcinoma in 9, and unilocular cystic renal cell carcinoma in 1 patient. Tumors were incidentally found during an evaluation of unrelated disease or a general health checkup in 14 patients (67%). The mean tumor size was 5.6 cm (range 0.5 to 12) for cystic necrosis and 5.4 cm (range 2 to 9) for multilocular cystic renal cell carcinoma. All 9 cases of multilocular cystic renal cell carcinoma were of the clear cell type and tumor grade 1. The mean follow-up period was 65 months (range 9 to 141). The 5-year disease-specific survival rates for multilocular cystic renal cell carcinoma and cystic necrosis were 100% and 80%, respectively. CONCLUSIONS: The prognosis for patients with cystic renal cell carcinoma is better than that for patients with solid tumors. In particular, the prognosis of multilocular cystic renal cell carcinoma is excellent. Multilocular cystic renal cell carcinoma represents a distinct subtype of renal cell carcinoma that can be completely cured by surgery.  相似文献   
993.
BACKGROUND: Donor-specific blood transfusion (DST) may improve allograft survival in human and animal models, but the mechanisms for this graft protective effect are incompletely understood. The sponge matrix allograft model was used to determine if DST induces regulatory factors within the allograft. METHODS: C57BL/6 (H-2b) recipients received donor-specific (DBA/2J, H-2d) or syngeneic (C57BL/6) blood 7 days before sponge matrix allograft (DBA/2J) implantation. Fourteen days postgrafting, the sponge infiltrating cells (SIC) were examined for cytotoxic T cell (CTL) and natural killer (NK) activity, and sponge exudate fluid (SEF) was assessed for nitric oxide (.N=O) and prostaglandin E2 (PGE2) content. Interleukin- (IL) 2, IL-4, IL-10, and interferon-gamma (IFN-gamma) production by SIC was also determined. Recipient splenocytes were simultaneously assessed for anti-donor cytotoxic and proliferative responses and .N=O production. RESULTS: SIC from mice receiving syngeneic transfusions (ST) acquired both CTL and NK activity postgrafting, with maximal activity by day 14. DST suppressed both CTL and NK activity throughout the postgrafting period. Limiting dilution analysis (LDA) of SIC to determine precursor and native CTL frequency showed significantly lower responder cell frequency after DST compared with ST. SEF .N=O levels and SIC production of IL-2 and IFN-gamma in grafted DST mice were significantly lower than in grafted mice receiving ST. No significant amounts of IL-4 and very low levels of IL-10 were produced by SIC from grafted mice after either ST or DST. Conversely, PGE2 content of sponge fluid and serum from DST mice was higher than in mice receiving ST. Antigen stimulated splenocyte proliferation and CTL development assessed by LDA were also inhibited by DST. CONCLUSIONS: Reduction in local TH1 cytokines, absence of detectable TH2 cytokines, with enhanced PGE2 and depressed .N=O were observed in the local graft environment after DST. These data support the hypothesis that DST induces donor-specific intragraft suppressor factors, accompanied by reduced local and systemic immune activation.  相似文献   
994.
995.
Although being a rapidly expanding socioeconomical burden worldwide, chronic obstructive pulmonary disease (COPD) is often overlooked because of its insidious progression. Since spirometry is the primary tool for the diagnosis of COPD, physicians should be aware of the disease in any situation where interpreting spirometry. This study was to estimate the prevalence of undiagnosed COPD among patients who underwent spirometry as a preoperative evaluation for elective surgeries. Patients aged 40 years or older who completed routine spirometry as a preoperative evaluation for elective surgeries between January to December, 2000. Medical records were reviewed for medical history, clinical findings, smoking status, and discharge diagnoses for patients who demonstrated airflow limitation (AL), defined as FEV(1)/FVC<70% on spirometry. Of the 1031 patients who qualified for the study, 263 (26%) presented AL. Sixty-nine of these patients with AL (26%) had underlying conditions that could account for AL, such as asthma and previously diagnosed COPD. The remaining 194 patients with AL (74%) were suspected to have undiagnosed COPD, 90% of which was mild in severity. Only 30 (15%) of these patients appeared to be diagnosed have received a diagnosed as COPD by physician on this occasion. This study testifies that COPD is often unnoticed, and demonstrates that every spirometry, such as in preoperative evaluation, gives a clue to identify affected individuals, for which awareness of the disease is essential.  相似文献   
996.
We studied 867 junior high school children and administered a questionnaire documenting allergic symptoms and environmental variables, and measured Immunoglobulin E serum levels and the immunoglobulin G titers of serum antibody to microflora. A total of 716 subjects were ultimately used for statistics; those with at least two of the following allergic symptoms: asthma, rhinitis, eczema, or food allergy, showed significantly higher IgG titers to Bactroides vulgatus than other groups. This finding suggests that a species of the Bacteroides genus of the intestinal microflora tends to affect the gut issues, but further studies are needed to clarify this.  相似文献   
997.
998.
The effects of dietary cholesterol and cholestyramine on pancreatic carcinogenesis initiated with N-nitrosobis(2-oxopropyl)amine (BOP) were investigated in 120 female Syrian golden hamsters. BOP (70 mg/kg body weight) was injected s.c. once at the beginning of the experiment. Starting 2 weeks later, the animals were then maintained on basal diet or diets containing either 0.5% cholesterol or 1% cholestyramine for a further 16 weeks. All surviving hamsters were killed at week 18, and the pancreas tissues examined histologically. The incidences of pancreatic carcinomas in hamsters fed cholesterol and the cholestyramine supplement were 40.0 and 30.0% respectively; in both cases significantly higher than the 6.9% incidence in the basal diet group. Cholesterol contents of the serum, pancreas and liver were significantly increased by cholesterol feeding and significantly decreased by the cholestyramine diet. The cholesterol diet also significantly increased pancreatic protein and DNA contents, and the concentration of total bile acids and the level of lithocholic acid in gallbladder bile. The cholestyramine diet significantly increased total pancreatic DNA and protein contents, and pancreatic weight. The results thus indicated that both dietary cholesterol and cholestyramine can enhance BOP-initiated pancreatic carcinogenesis in hamsters.  相似文献   
999.
In this study, we report on the efficacy of combination therapy of second‐generation antihistamine antagonist, fexofenadine hydrochloride, and leukotriene receptor inhibitor, montelukast sodium, for the treatment of 15 prurigo nodularis or pemphigoid nodularis patients, in whom conventional therapy was ineffective. All patients received 10 mg montelukast once a day and 240 mg fexofenadine twice a day for 4 weeks in addition to other medications they had been taking. We assessed the manifestations of the lesions and itching intensity before and after the therapy, and we evaluated each patient as (i) markedly improved, (ii) improved, (iii) slightly improved, (iv) no change, (v) worse. Two patients (13.3%) were evaluated as markedly improved, and the lesions of one patient completely disappeared. Three patients (20.0%) were evaluated as improved, and six patients (40.0%) as slightly improved. Thus, 11 of 15 cases (73.3%) improved by combination therapy of fexofenadine and montelukast, in which nine cases (75.0%) of prurigo nodularis and two cases (66.7%) of pemphigoid nodularis were involved. No patients revealed any side effects. This study revealed that combination therapy of fexofenadine and montelukast was effective for some patients with conventional therapy‐resistant prurigo nodularis and pemphigoid nodularis.  相似文献   
1000.
Neurofibromatosis type 1 (NF1) is a well‐known genetic disorder characterized by café‐au‐lait spots and neurofibromas, but many other clinical characteristics and associated comorbidities also have been reported. This study aimed to characterize NF1 further by investigating its association with anthropometric characteristics and other diseases. We performed a case–control study of 227 NF1 patients (101 male, 126 female) and a randomly selected age‐ and sex‐matched control group of 681 non‐NF1 patients (303 male, 378 female) who visited our institution in Japan. We examined adult (≥20 years) height and body mass index (BMI), and, in the total sample, allergic diseases (bronchial asthma [BA], atopic dermatitis [AD] and allergic rhinitis) and other respiratory cardiovascular and psychiatric disorders. In adults, the mean BMI was lower in the NF1 group than in the control group, and was significantly statistically different among men (= 0.0238). In the whole sample, the prevalences of BA (= 0.0184), AD (= 0.0144) and valvular heart disease (= 0.0166) were significantly greater in the NF1 group than in the control group. To date, no similar research on the BMI or the prevalence of allergic disease in NF1 patients has been reported. Our results suggest that NF1 patients tend to have lower BMI and may have alterations in specific metabolic pathways and altered allergic immunity.  相似文献   
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