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101.
Fracture risk assessment based solely on BMD has limitations. Additional risk factors include the presence of a previous low‐trauma fracture. We sought to quantify the fracture burden attributable to first versus repeat fracture. We studied 2179 men and 5269 women, 50–90 yr of age, participating in the Canadian Multicentre Osteoporosis Study (CaMos). We included all low‐trauma fractures that occurred over 8 yr of follow‐up and classified these as either first or repeat clinical low‐trauma fracture based on lifetime fracture history. Analyses were further stratified by sex, age, BMD risk categories (normal, osteopenia, osteoporosis), and vertebral deformity status. There were 128 fractures in men and 577 fractures in women. About 25% of fractures in men and 40% in women were repeat fractures. Just over one half of first fractures occurred in those with osteopenic BMD (58% in men, 54% in women). Just under one half of repeat fractures also occurred in those with osteopenic BMD (42% in men, 47% in women). The incidence of repeat fracture was, in most cases, nearly double, but sometimes nearly quadruple, the incidence of first fracture within a given BMD risk category in both men and women. Repeat fractures contribute substantially to overall fracture burden, and the contribution is independent of BMD. Furthermore, those with a combination of prior low‐trauma fracture and another risk factor were at especially high risk of future fracture.  相似文献   
102.
Purpose  The number of anesthesiologists per population in Japan is small compared with that in Europe and North America. While there is a growing concern that hard work causes anesthesiologists’ fatigue and may compromise patient safety, the workload and physical stress, as well as the impact of staff support on physicians’ stress have not been assessed in detail. The goal of this study was to evaluate the working environment, anesthesia workload, and occupational stress of anesthesiologists in Japan. Methods  A questionnaire survey was performed targeting 1010 members of the Japanese Society of Anesthesiologists working as anesthesiologists affiliated with acute care hospitals in Japan. Data on background information, working environment, operation anesthesia duties, and stress were collected, and the relationship of work stress with background, environment, and anesthesia duties was evaluated by linear regression analysis. Results  Responses were obtained from 383 full-time anesthesiologists (response rate, 43.9%). The total anesthesia time per week was 23.6 h on average. The work stress score was 114.3 ± 30.2 (mean ± SD) when the average workers’ work stress score in Japan was 100. The work stress score was significantly associated with “years of experience” (with experience < 10 years considered as the reference; 10–19 years: β = −0.18, P = 0.02, ≥20 years: β = −0.15, P = 0.04), “hospital with ≥500 beds” (with a hospital with ≤ 299 beds considered as the reference; β = 0.15, P = 0.04), “total time of anesthesia per week” (β = 0.18, P.02), “estimated annual cases managed by an anesthesiologist” (β = 0.12, P = 0.04) and “no-support stress” (β = 0.21, P < 0.01) on linear regression analysis (R2 = 0.12). Conclusion  Our results provide a quantitative assessment of the duties of anesthesiologists and show that work stress among anesthesiologists is related to workload and other factors. Summaries of this study were presented at the 53rd and 54th General Meetings of the Japanese Society of Anesthesiologists (JSA) at Kobe (2006) and Sapporo (2007).  相似文献   
103.
Among patients with negative initial biopsies of the prostate, 51 patients underwent total 59 repeat biopsies at the Department of Urology of Ikeda Municipal Hospital between January 1998 and April 2004. Overall 26 patients (44.1%) were confirmed to have cancer, 22 patients by second repeat biopsy (22/51), four patients by third biopsy (4/7) and none by fourth biopsy (0/1). Clinical parameters (age, PSA, PSA density, PSA velocity) were analyzed for the possibility to predict the pathological outcome. Significant differences between the positive biopsy group and the negative biopsy group were obtained in age, PSA level and prostatic volume. Of the diagnostic evaluations including palpation and imaging studies (DRE, TRUS, MRI), the most powerful predictor for prostate cancer seemed to be the MRI findings, especially in the cases of short-interval repeat biopsy. Biopsies directed at the positive lesion on MRI in addition to systematic prostate biopsies should be useful.  相似文献   
104.
Hepatoblastoma is the most common malignant liver tumor in children. Recently, liver transplantation has been indicated for unresectable hepatoblastoma. We retrospectively reviewed 14 children with a diagnosis of hepatoblastoma who had undergone living-donor liver transplantation (LDLT) at Kyoto University Hospital. During the period from June 1990 to December 2004, 607 children underwent LDLT. Of these interventions, 2.3% were performed for hepatoblastoma. Based on radiological findings, the pre-treatment extent of disease (PRETEXT) grouping was used for pre-treatment staging of the tumor. There were grade III in seven patients and grade IV in seven patients. Thirteen patients received chemotherapy, and seven underwent hepatectomy 11 times. Immunosuppressive treatment consisted of tacrolimus monotherapy in 11 patients. Actuarial 1- and 5-year graft and patient survival rates were 78.6% and 65.5%. The poor prognostic factors were macroscopic venous invasion and extrahepatic involvement with 1-year and 5-year survival rates of 33.0% and 0%. Pediatric patients without these factors showed an acceptable 5-year survival rate of 90.9%. LDLT provides a valuable alternative with excellent results in children with hepatoblastoma because it allows optimal timing of the liver transplantation, given the absence of delay between the completion of chemotherapy and planned liver transplantation.  相似文献   
105.
Effects of lidocaine on parameters of membrane functional integrity were investigated in the mouse brain. Changes in the direct-current potential shift in the cerebral cortex provoked by decapitation ischemia were compared in animals given lidocaine (0.05, 0.25, or 1.0 micromol, intracerebroventricular) or saline 15 minutes before ischemia. The brain content of adenosine 5'-triphosphate (ATP) was measured in animals subjected to 0, 0.5, 1, and 2 minutes of decapitation ischemia, and the effect of preischemic administration of lidocaine (0.25 micromol, intracerebroventricular) was evaluated. Na+, K+-ATPase, and Ca2+-ATPase activity was evaluated in brains pretreated with lidocaine (0.25 micromol, intracerebroventricular) or saline 15 minutes before decapitation. Changes in the intracellular Ca concentration ([Ca2+]i) were evaluated in hippocampal slices and the effects of lidocaine (50, 100, or 400 microM) were assessed in the hippocampal CA1 field and dentate gyrus at pH 7.4 and pH 6.8 every 60s for a duration of 50 min. The preischemic administration of lidocaine (1.0 and 0.25 micromol) delayed the onset of anoxic depolarization to 49 seconds and 44 seconds, respectively, as compared with that in the saline group at 27 seconds. Lidocaine maintained ATP levels higher than those in corresponding saline groups, values being 165% after 1 minute of ischemia and 212% after 2 minutes, respectively. Lidocaine did not affect Na+, K+-ATPase, and Ca2+-ATPase activity. Lidocaine did not affect changes in the [Ca2+]i in either area at either pH. The findings may suggest that lidocaine maintains the energy level by delaying depolarization in neurons, which may contribute to removal of cytosolic Ca2+ in ischemic states.  相似文献   
106.
Background: Midazolam and propofol often provoke retrograde amnesia after recovery from anesthesia in humans. Because an increase in central serotonergic activity impairs learning and memory, the authors examined the relation between changes in the serotonergic activity caused by intravenous anesthetics and memory.

Methods: Changes in extracellular concentrations of monoamines and their metabolites were investigated in rat striatum by a microdialysis procedure, and the effects of intraperitoneal injections of midazolam (5 mg/kg), propofol (60 mg/kg), and pentobarbital (15 mg/kg) were then examined. To evaluate the behavioral alteration with these agents, the authors used a step-through passive avoidance test.

Results: Midazolam and propofol slightly increased the extracellular concentration of 5-hydroxytryptamine in the striatum, although pentobarbital did not produce any changes. Midazolam and propofol increased the extracellular concentration of 5-hydroxyindoleacetic acid, a metabolite of 5-hydroxytryptamine, with the peak values each 138% and 138% of that in saline-injected animals, respectively. However, pentobarbital decreased the 5-hydroxyindoleacetic acid concentration to 61% of that in the saline group. Administration of midazolam or propofol immediately after the completing the passive avoidance learning reduced step-through latencies after 24 h, although pentobarbital-injected animals maintained a consistent performance. The effects of midazolam and propofol on step-through latencies were completely antagonized by intracerebroventricular administration of spiroxatrine (5 [mu]g), a 5-hydroxytryptamine 1A antagonist, 30 min before training.  相似文献   

107.
BACKGROUND: A-3826G polymorphism within the promoter region of the uncoupling protein-1 (UCP-1) gene is possibly involved in the pathophysiology of obesity and metabolic disorders. However, the effects of UCP-1 A-3826G polymorphism on high-density lipoprotein cholesterol (HDL-C), a major contributor to atherosclerotic disease, still have not been established. METHODS: A total of 298 healthy Japanese subjects (144 males and 154 females, mean age: 45.2 years) with a body mass index (BMI) of 20.0-30.0 kg/m(2), regular lifestyles, and receiving no medication were enrolled in the cross-sectional study to estimate the relationship of serum HDL-C levels with UCP-1 A-3826G polymorphism by genomic PCR and Bcl1-restriction fragment length polymorphism analysis. We used 1.04 mmol/L of HDL-C in Japanese males and 1.29 mmol/L in Japanese females as cut-off values of low HDL-cholesterolemia. RESULTS: The genotype and allele frequencies of UCP-1 A-3826G polymorphism were similar to those previously reported in the Japanese population. In males, HDL-C levels of the GG genotype (1.75+/-0.49 mmol/L) were significantly higher than those found in the AA genotype (1.45+/-0.34 mmol/L, p=0.015). In females, the occurrence rate of low HDL-cholesterolemia was significantly different by genotype: a low prevalence in the GG genotype (15.4% in the AA, 4.8% in the AG, 15.4% in the GG genotype, p=0.022). Logistic regression analysis was used to identify risk factors for low HDL-cholesterolemia, with adjustments for age, gender, smoking, alcohol intake, BMI, hypertriglyceridemia, and genotype. The GG genotype was detected as being a significant associated factor (odds ratio =0.11 [95% confidence interval =0.01-0.90], p=0.01), in addition to BMI and the presence of hypertriglyceridemia. CONCLUSIONS: These results suggest that the GG genotype may be an independent protective factor associated with low HDL-cholesterolemia in this population, although the role of the UCP-1 A-3826G polymorphism in HDL-C is complex and remains controversial. This hypothesis needs further investigation.  相似文献   
108.
There is mounting evidence that Th2 cytokines adversely affect skin barrier functions and contribute to the pathogenesis of atopic dermatitis (AD). AD is also characterized by abnormal cohesion in the stratum corneum (SC). However, the contribution of Th2 cytokines to this abnormality remains unknown. This study examined the effects of IL‐4, a prototypic Th2 cytokine, on the cohesion of the SC. Structural and physiological assessments revealed that repeated intradermal injections of IL‐4 compromised the cohesion of the SC of normal hairless mice. Two potential mechanisms were explored to account for the altered cohesion. First, IL‐4 decreased the amount of corneodesmosomes and down‐regulated the expression of desmoglein 1, but not of corneodesmosin (CDSN) or loricrin expression, in murine skin and in cultured human keratinocytes (KC). IL‐4 did not affect the skin surface pH, and in situ zymography revealed no net change in total serine protease activity in the IL‐4‐treated SC. Yet, IL‐4 enhanced expression of kallikrein (KLK)7, while simultaneously down‐regulating KLK5 and KLK14. Finally, IL‐4 did not alter the expression of the lympho‐epithelial Kazal‐type inhibitor (LEKTI) in KC. This study suggests that IL‐4 abrogates the cohesion of SC primarily by reducing epidermal differentiation.  相似文献   
109.
BACKGROUND: The differentiation between linear IgA bullous dermatosis (LABD) and bullous pemphigoid (BP) is sometimes difficult in patients who have both IgA and IgG deposition in a linear pattern at the basement membrane zone. OBJECTIVE: We address whether two cases of acquired subepidermal blistering disease with coexistence of IgA and IgG deposition in a linear pattern at the basement membrane zone are LABD or BP. METHODS: The two cases were investigated by immunoelectron microscopy and compared with two typical cases of LABD. RESULTS: In both cases, the deposition of IgA and IgG was ultrastructurally localized below the lamina densa in close association with anchoring fibrils, as was seen in two cases of typical LABD. CONCLUSION: These findings indicate that our two cases of acquired blistering disease with co-existence of IgA and IgG deposition are LABD, rather than BP.  相似文献   
110.

Background

In 1999, the Japanese Orthopaedic Association decided to develop a new Cervical Myelopathy Evaluation Questionnaire (JOACMEQ). The final version of the JOACMEQ, comprising 24 questions and five domains (cervical spine function (CF); upper extremity function (UF); lower extremity function (LF); bladder function (BF); and quality of life (QOL)), was established after three nationwide investigations. The fourth investigation, reported in this paper, was performed to confirm the responsiveness of the questionnaire.

Methods

A total of 137 patients with cervical myelopathy were included in the study. Each patient was interviewed twice using the JOACMEQ before and after treatment. At the second interview, the patients self-rated their condition in five domains for “worse,” “somewhat worse,” “no change,” “somewhat better,” or “better,” and these scores were defined as the external assessment rating. The difference of the points in five domains between the first and the second interview was calculated against each external assessment. Based on the results, substantial clinical benefit (SCB) thresholds for the JOACMEQ were determined.

Results

The statistically significant median values of the acquired points were 17.5 for CF, 16.0 and 21.0 for UF, 27.0 and 20.5 for LF, 13.0 for BF, and 29.0 for QOL. After consideration of the results, the committee decided that an acquired point ≥20 could be interpreted as representing an SCB threshold for the JOACMEQ.

Conclusion

We have concluded that a treatment can be judged to be effective for a patient if 1) The patient give all answers for the questions necessary to calculate the functional score of a domain and an increase of ≥20 points is obtained for that score, or 2) The functional score after treatment is > 90 points even if the answer for the unanswered questions was supposed to be the worst possible choice.  相似文献   
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