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71.
Summary The principle of bowel detubularization to decrease peristaltic pressure and increase reservoir capacity is applied in contemporary continent urinary diversions. The process of detubularization and refashioning of the spatulated bowel segment approximates 1 of operating time and is the most time-consuming aspect of pouch construction. The employment of devices applying absorbable staples (absorbable staplers) has substantially reduced the time required to fashion bowel reservoirs. This article reviews the adaptation of the absorbable stapler to continent urinary diversion using small- and large-bowel segments.  相似文献   
72.
The influence of quercetin, chlorpromazine, aristolochic acid, and indomethacin on group I phospholipase A2 (PLA2) from porcine pancreas and on group II PLA2 fromVipera russelli was compared. Quercetin and chlorpromazine were found to inhibit PLA2 activity in lower concentrations (< 100M), while aristolochic acid and indomethacin were inhibitory only in higher concentrations (> 100M). The order of potency againstVipera PLA2 was: quercetin >chlorpromazin aristolochic acid > indomethacin, while the order of potency against pancreatic PLA2 was: chlorpromazine > aristolochic acid > indomethacin> quercetin. Thus, quercetin was a potent inhibitor towards group II PLA2 (IC50=2M), but a very weak inhibitor against group I PLA2, with maximum 30% inhibition. Aristolochic acid and indomethacin were three to four times more potent towards group II PLA2 than towards group I PLA2, while chlorpromazine was equally potent towards the two PLA2 types. Quercetin and chlorpromazine were also tested against two PLA2 fractions purified from the plasma of septic shock patients; chlorpromazine was then equally potent towards the two PLA2 fractions, whereas quercetin was a potent inhibitor of only one of the two PLA2 fractions (IC50=4M). Together, these results indicate that (1) different PLA2 inhibitors have different potency depending on which type of PLA2 they are used against, (2) quercetin selectively inhibits group II PLA2 and may therefore be used to discriminate between different PLA2 forms in biological materials, and (3) both PLA2 of group I and group II are present in septic shock plasma.  相似文献   
73.
Summary The possibility that -adrenoceptor blockers, especially 1-selective agents might inhibit platelet function is of considerable interest, as this might be of pathophysiological importance in cardiovascular diseases. Platelet function, however, is difficult to assess and in vivo related data are scarce.The effect of one week of treatment with metoprolol 200 mg/day on platelet aggregability during mental stress (colour word conflict test; CWT) and low and high dose adrenaline infusions has been evaluated in a double-blind, placebo-controlled, cross-over study in 10 healthy male volunteers. Platelet function in vivo was assessed using ex vivo filtragometry, and the urinary excretions of -thromboglobulin (HMW -TG) and 11-dehydro-TxB2 (a thromboxane metabolite). Conventional in vitro aggregometry and the urinary levels of 2,3-dinor-6-keto-PGF1 (a prostacyclin metabolite) were also studied.During the interventions there was increased platelet aggregability in vivo, as filtragometry readings were shortened by 41±11% during high dose adrenaline infusion, urinary HMW -TG levels increased and urinary 11-dehydro-TxB2 tended to increase. In contrast, platelet sensitivity to ADP in vitro was reduced. The urinary 2,3-dinor-6-keto-PGF1 levels were increased during the interventions.Despite the cardiovascular and biochemical signs of -adrenoceptor blockade at rest and during the interventions, metoprolol failed to influence platelet function in vivo, as measured by ex vivo filtragometry, or urinary HMW -TG or 11-dehydro-TxB2 levels. It tended rather to enhance the stress response measured by ex vivo filtragometry. Platelet aggregability in vitro and urinary 2,3-dinor-6-keto-PGF1 levels were not altered by metoprolol.Thus, metoprolol was not found to reduce platelet aggregability in healthy male volunteers either at rest or during sympatho-adrenal activation. The effect of treatment may still differ in patients; studies in patients with ischaemic heart disease are under way.  相似文献   
74.
CSF and serum was obtained from 216 patients with neurological or psychoneurotic symptoms and the concentrations of albumin and IgG were immunologically determined. The IgG/albumin index, calculated as the quotient of the CSF/serum ratios of IgG and albumin was compared with electrophoresis on agar gel. In "normal" cases, the IgG/albumin index was between 0.26-0.66. Pathological electrophoresis, i.e. with two or more IgG bands in the gamma globulin region was found in 85 per cent of the MS patients; in 29 per cent of the patients with a possible demyelinating disease; in 41 per cent of patients with CNS infection; and in 4 per cent of patients with other neurological disorders; whereas an increased IgG/albumin index ( greater than 0.66) was found in 88 per cent of the MS patients; in 43 per cent of the patients with a possible demyelinating disease; in 50 per cent of the patients with CNS infection; in 11 per cent of patients with immunological disorders; and in 18 per cent of patients with other neurological diseases. The increase of the IgG/albumin index was sometimes moderate (0.67-0.90), except in patients with MS, syphilis and other CNS infections, where a pathological electrophoresis combined with an IgG/albumin index above 1.0 was found to be a valuable support for the clinical diagnosis.  相似文献   
75.
BACKGROUND: Transplanted islets lack endothelial cells immediately after implantation and therefore depend on an adequate revascularization for their survival and function. However, the functional properties of the newly formed islet graft microvessels are largely unknown. This study aimed to investigate the blood flow regulation of transplanted pancreatic islets. METHODS: Pancreatic islets were syngeneically transplanted beneath the renal capsule of control and streptozotocin-diabetic rats. Blood flow measurements were performed 4 weeks later using laser-Doppler flowmetry. Adenosine (0.6 mg x kg(-1) x min(-1), angiotensin II (AT II; 0.17 microg x kg(-1) x min(-1)) and the nitric oxide synthase inhibitor NG-nitro-L-arginine (25 mg/ kg) were given to each animal. RESULTS: An increased basal blood flow and basal vascular conductance in the islet grafts, but not in the renal cortex, were seen in diabetic rats compared with control rats. Adenosine increased, and AT II decreased, the vascular conductance of the islet grafts in both nondiabetic and diabetic animals. A more pronounced circulatory response to AT II was observed in kidneys of diabetic animals, whereas there was no difference in the islet graft blood flow response between nondiabetic and diabetic animals. NG-Nitro-L-arginine decreased islet graft blood flow and vascular conductance in both nondiabetic and diabetic recipients, but the effect was more pronounced in the non-diabetic animals. CONCLUSIONS: Islet graft blood flow was influenced by adenosine, AT II, and nitric oxide inhibition in all animals. However, diabetic animals were less dependent on nitric oxide to maintain a basal blood flow in the islet graft.  相似文献   
76.
PURPOSE: The role of unrelated allogeneic stem-cell transplantation in acute lymphoblastic leukemia (ALL) patients is still not clear, and only limited data are available from the literature. We analyzed factors affecting clinical outcome of ALL patients receiving a related or unrelated stem-cell graft from matched donors. PATIENTS AND METHODS: The total study population was 264 adult patients receiving a myeloablative allogeneic stem-cell transplant for ALL at nine bone marrow transplantation centers between 1990 and 2002. Of these, 221 patients receiving a matched related or unrelated graft were analyzed. One hundred forty-eight patients received transplantation in complete remission; 62 patients were in relapse; and 11 patients were refractory to chemotherapy before transplant. Fifty percent of patients received bone marrow, and 50% received peripheral blood stem cell from a human leukocyte antigen-identical related (n = 103), or matched unrelated (n = 118) donor. RESULTS: Disease-free survival (DFS) at 5 years was 28%, with 76 patients (34%) still alive (2.2 to 103 months post-transplantation), and 145 deceased (65 relapses, transplant-related mortality, 45%). We observed an advantage regarding DFS in favor of patients receiving transplantation during their first complete remission (CR) in comparison with patients receiving transplantation in or after second CR (P =.014) or who relapsed (P <.001). We observed a clear trend toward improved survival in favor of B-lineage ALL patients compared with T-lineage ALL patients (P =.052), and Philadelphia chromosome-positive patients had no poorer outcome than Philadelphia chromosome-negative patients. Total-body irradiation-based conditioning improved DFS in comparison with busulfan (P =.041). CONCLUSION: Myeloablative matched related or matched unrelated allogeneic hematopoietic stem-cell transplantation in ALL patients should be performed in first CR.  相似文献   
77.
A cohort of offspring of mothers with breast or ovarian cancer diagnosed in 1958-1993 was established using Swedish population-based registers. The children (n = 158,041) were born between 1941 and 1993, and their cancer incidence was followed between 1961 and 1993. A total of 3,257 tumors in 3,102 children were found. Observed numbers of cases were compared with expected numbers based on national calendar year-, age-, and sex-specific incidences. For daughters of women with breast cancer, the standardized morbidity ratios for being diagnosed with breast cancer and ovarian cancer before age 50 years were 1.99 (95% confidence interval (CI): 1.86, 2.14) and 1.28 (95% CI: 1.05, 1.54), respectively. The corresponding figures for daughters of women with ovarian cancer were 1.79 (95% CI: 1.55, 2.07) and 2.38 (95% CI: 1.77, 3.12). The risks were raised if the mother's cancer was diagnosed at a young age, the mother had multiple breast/ovarian diagnoses, or there was a sister with breast/ovarian cancer. Among all offspring, increased risks were found for thyroid cancer, testicular cancer, and malignant melanoma, while lung cancer risk was decreased if the mother had had breast cancer. The authors developed a variance estimator for the standardized morbidity ratio to cope with overdispersion due to dependency within families.  相似文献   
78.
Transplantation of pancreatic islets may provide a cure for type 1 diabetes. However, this treatment can currently be offered only to very few patients. To improve transplantation success we need to understand better the mechanisms of how the implanted islets survive, grow and/or maintain adequate function. We herein report on our studies to evaluate the factors responsible for the engraftment, i.e. revascularization, reinnervation etc., of transplanted islets and relate these factors to the metabolism and growth of the islets. Graft metabolism can be monitored by microdialysis probes that allow for the measurement of minute amounts of islet metabolites and hormonal products. Growth of the endocrine cells can be stimulated both in vitro before implantation and in vivo post-transplantation. Another problem is rejection of transplanted islets, which may be overcome by the microencapsulation of islets. The knowledge gained by the present studies will enable us to elucidate the optimal treatment of islets to ensure a maximal survival of the transplanted islets, and may be applied also to clinical islet transplantation.  相似文献   
79.
80.
儿童皮下和网膜脂肪组织瘦素表达水平及其临床意义   总被引:1,自引:1,他引:1  
【目的】 对不同年龄儿童皮下和网膜脂肪组织中瘦素 (leptin)mRNA表达水平进行调查。  【方法】 配对的皮下和网膜脂肪组织从腹部择期手术患儿 ( 3 7例 ,3月~ 12岁 )和成人 ( 9名 )获取。应用real timeRT PCR方法测定不同部位脂肪组织中leptinmRNA表达水平 ,并探讨其与体块指数 (BMI)、腰围、臀围及腰臀围比 (WHR )、年龄、性别及肥胖的相互关系。 【结果】 与成人相一致 ,儿童leptin的表达亦有明显的部位性差异 ,皮下脂肪组织中leptinmRNA水平显著高于网膜 (P <0 .0 0 1)。皮下脂肪组织leptinmRNA表达水平与BMI呈显著正相关 (r =0 .69,P <0 .0 0 1) ,而网膜leptin与BMI呈较弱的正相关 (r =0 .3 2 ,P <0 .0 5 ) ;皮下和网膜leptin与WHR的均无显著相关 ,但网膜leptin与腰围呈较弱的正相关 (r =0 .3 3 ,P <0 .0 5 )。不同年龄组中脂肪组织的leptin表达水平差异有显著性(P <0 .0 1) ,6~ 12岁组皮下和网膜脂肪组织leptinmRNA表达均高于 1~ 5岁组 (P <0 .0 5 ) ,与成人水平相比 ,则差异无显著性 (P >0 .0 5 )。过重和肥胖儿童脂肪组织leptinmRNA表达水平显著高于非肥胖儿童。  【结论】 儿童不同部位脂肪组织leptinmRNA表达水平在一定程度上反映了脂肪组织的生长和分布。肥胖儿童脂肪组织leptin的  相似文献   
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