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61.
Nitric oxide (NO) has important functions in the regulation of pulmonary smooth muscle tone. In the human lung, published data on the expression and distribution of neuronal nitric oxide synthase (NOS-I) are contradictory. The aim of this study, therefore, was to determine the predominant cells expressing NOS-I in the human lung. Immunofluorescence double staining techniques were applied to normal human lung tissue using established monospecific antibodies directed against NOS-I. Suprisingly, capillary endothelial cells in the alveolar septa were identified as the major sites of NOS-I expression. Neither alveolar nor bronchiolar epithelium, nor the alveolar macrophages, expressed NOS-I. These results indicate that the predominant sites of NOS-I expression in the human lung are confined to non-neuronal, i.e. capillary endothelial cells and suggest a role for NO in the regulation of pulmonary endothelial cell permeability.  相似文献   
62.
OBJECTIVES: ITo examine the economic impact of Alzheimer's disease (AD) as the disease progresses on patients' medical costs and caregivers' productivity. DESIGN: A 12-page, self-administered mail survey, fielded in November 1999. SETTING: Households with AD caregivers, selected from a nationwide (U.S.) consumer database. PARTICIPANTS: One thousand seven hundred fifteen caregivers of noninstitutionalized AD patients. MEASUREMENTS: Disease progression was measured using a scale of symptom frequency and measures of instrumental and physical functioning. Cost components included hospital days, physician visits, and emergency room visits. Lost productivity was assessed using hours per week that caregivers provided care and the number of days that they missed from work because of caregiving. RESULTS: The direct costs of caring for AD patients for 6 months totaled $3,129, whereas the indirect costs were $26,080. Patients with more-frequent symptoms used all healthcare resources, including the hospital, emergency room, and physicians, more often than those with less-frequent symptoms. Those with lower levels of physical and instrumental functioning also used the hospital and physicians more often than those with higher levels of physical and instrumental functioning. Caregivers of these more severely impaired patients spent more hours providing care and reported missing more work than those caring for higher-functioning patients. These relationships remained after controlling for potentially confounding factors. CONCLUSIONS: This large study of patients at all stages of AD shows that the direct and indirect costs of AD are considerably lower for patients with fewer symptoms. Longitudinal studies will determine the impact on the overall cost of care of interventions that reduce symptoms and maintain patients at earlier stages of the disease.  相似文献   
63.
The surgical treatment of haemorrhoids with the use of a circular stapler is a novel method. A comparative retrospective study of two groups of patients treated surgically for third- and fourth-degree haemorrhoids was conducted. Fifty patients (group A) underwent a surgical intervention with the circular stapler in the rectal mucosa 4 cm above the dentate line. In another group of 50 patients (group B), the standard open haemorrhoidectomy (Milligan-Morgan) was carried out. The new method (group A) compared with the standard haemorrhoidectomy (group B) was found to be less time consuming (mean time, 10±2 minutes vs. 35±5 minutes, p<0.001). The majority of patients (28) in group A experienced mild pain (VAS, 3–5) while pain for the majority of patients in group B was 5–7 on the VAS scale (p<0.01). The duration of postoperative hospitalisation was 1±1 days for the patients of group A and 5±2 days for the patients of group B (p<0.05). The early postoperative bleeding rate was 6% in group A and 12% in group B (p<0.01). None of the patients of group A developed incontinence and 6 (12%) patients in group B developed mild liquid incontinence during the first postoperative month. During the period of follow-up (12 months to 3 years, median length 18 months in outpatient visits), no patient in either group developed recurrence of haemorrhoids or rectal prolapse. In conclusion, the surgical treatment of haemorrhoids with the circular stapler seems to be an efficient alternative to the standard open haemorrhoidectomy when this is indicated. Received: 28 April 2000 / Accepted in revised form: 18 October 2000  相似文献   
64.
Composite neoplasms, carcinoid and adenocarcinoma have been reported to occur in several parts of the body, including the stomach, ampulla of Vater, large bowel, lung, and urinary bladder. Here we report a case of a 74-year-old male with a composite carcinoid-adenocarcinoma of the ileum associated with a transitional cell carcinoma of the bladder. The microscopical examination of the composite tumor showed an admixture of typical carcinoid tumor and moderately a differentiated adenocarcinoma. Immunohistochemically, the two components showed clear-cut differentiations. A review of the literature revealed that this is the first reported case of composite carcinoid-adenocarcinoma of the ileum associated with transitional cell carcinoma of the urinary bladder.  相似文献   
65.
Recently, a hexanucleotide (GGGGCC) repeat expansion in the first intron of C9ORF72 was reported as the cause of chromosome 9p21‐linked frontotemporal dementia‐amyotrophic lateral sclerosis (FTD‐ALS). We here report the prevalence of the expansion in a hospital‐based cohort and associated clinical features indicating a wider clinical spectrum of C9ORF72 disease than previously described. We studied 280 patients previously screened for mutations in genes involved in early onset autosomal dominant inherited dementia disorders. A repeat‐primed polymerase chain reaction amplification assay was used to identify pathogenic GGGGCC expansions. As a potential modifier, confirmed cases were further investigated for abnormal CAG expansions in ATXN2. A pathogenic GGGGCC expansion was identified in a total of 14 probands. Three of these presented with atypical clinical features and were previously diagnosed with clinical olivopontocerebellar degeneration (OPCD), atypical Parkinsonian syndrome (APS) and a corticobasal syndrome (CBS). Further, the pathogenic expansion was identified in six FTD patients, four patients with FTD‐ALS and one ALS patient. All confirmed cases had normal ATXN2 repeat sizes. Our study widens the clinical spectrum of C9ORF72related disease and confirms the hexanucleotide expansion as a prevalent cause of FTD‐ALS disorders. There was no indication of a modifying effect of the ATXN2 gene.  相似文献   
66.
AIM: To determine the prevalence of bipolar disorder (BD) and sub-threshold symptoms in children with attention deficit hyperactivity disorder (ADHD) through 14 years’ follow-up, when participants were between 21-24 years old.METHODS: First, we examined rates of BD type I and II diagnoses in youth participating in the NIMH-funded Multimodal Treatment Study of ADHD (MTA). We used the diagnostic interview schedule for children (DISC), administered to both parents (DISC-P) and youth (DISCY). We compared the MTA study subjects with ADHD (n = 579) to a local normative comparison group (LNCG, n = 289) at 4 different assessment points: 6, 8, 12, and 14 years of follow-ups. To evaluate the bipolar variants, we compared total symptom counts (TSC) of DSM manic and hypomanic symptoms that were generated by DISC in ADHD and LNCG subjects. Then we sub-divided the TSC into pathognomonic manic (PM) and non-specific manic (NSM) symptoms. We compared the PM and NSM in ADHD and LNCG at each assessment point and over time. We also evaluated the irritability as category A2 manic symptom in both groups and over time. Finally, we studied the irritability symptom in correlation with PM and NSM in ADHD and LNCG subjects.RESULTS: DISC-generated BD diagnosis did not differ significantly in rates between ADHD (1.89%) and LNCG 1.38%). Interestingly, no participant met BD diagnosis more than once in the 4 assessment points in 14 years. However, on the symptom level, ADHD subjects reported significantly higher mean TSC scores: ADHD 3.0; LNCG 1.7; P < 0.001. ADHD status was associated with higher mean NSM: ADHD 2.0 vs LNCG 1.1; P < 0.0001. Also, ADHD subjects had higher PM symptoms than LNCG, with PM means over all time points of 1.3 ADHD; 0.9 LNCG; P = 0.0001. Examining both NSM and PM, ADHD status associated with greater NSM than PM. However, Over 14 years, the NSM symptoms declined and changed to PM over time (df 3, 2523; F = 20.1; P < 0.0001). Finally, Irritability (BD DSM criterion-A2) rates were significantly higher in ADHD than LNCG (χ2 = 122.2, P < 0.0001), but irritability was associated more strongly with NSM than PM (df 3, 2538; F = 43.2; P < 0.0001).CONCLUSION: Individuals with ADHD do not appear to be at significantly greater risk for developing BD, but do show higher rates of BD symptoms, especially NSM. The greater linkage of irritability to NSM than to PM suggests caution when making BD diagnoses based on irritability alone as one of 2 (A-level) symptoms for BD diagnosis, particularly in view of its frequent presentation with other psychopathologies.  相似文献   
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68.
Gastrocolic fistula is rarely described in the literature. It has been associated with a variety of diseases and recently with benign gastric ulcers related to the use of nonsteroidal anti-inflammatory drugs (NSAIDs'). The present case represents the first report of gastrocolic fistula due to NSAIDs in a cirrhotic patient. This is in keeping with the established knowledge that cirrhotic patients constitute a high-risk group of patients when treated with NSAIDs'. Review of the literature shows that this condition warrants a complete diagnostic work-up to exclude more ominous underlined diseases.  相似文献   
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