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31.
PURPOSE: To determine the long-term prognosis of patients who develop a local recurrence (LR) after conservative surgery (CS) and radiation therapy (RT) for early-stage invasive breast cancer. METHODS AND MATERIALS: Between 1970 and 1987, 2102 patients with clinical Stage I-II breast cancer were treated with CS+RT. LR was defined as any recurrence within the ipsilateral breast with or without simultaneous regional nodal or distant metastasis. Patients were at risk for a LR until the first of distant metastases, second nonbreast malignancy, or death (DF/S/D). The final study population comprised 341 patients with LR. The median time to LR was 72 months. The median follow-up time after LR was 85 months. A proportional hazards model of time from LR to DF/S/D was done to investigate the influence of factors at initial diagnosis and at LR on subsequent outcome. RESULTS: The actuarial freedom from DF/S/D 5 years after LR was 65% and the survival was 81%. Variables significantly associated with time to DF/S/D were: LR histology (invasive vs. ductal carcinoma in situ, hazard ratio [HR] = 4.1, p < 0.0001); local therapy for LR (none vs. mastectomy or unknown, HR = 3.2, p < 0.0001; and CS +/- RT vs. mastectomy or unknown, HR = 2.0, p = 0.02); time to LR (< or =2 years vs. >5 years, HR = 2.6, p < 0.0001; and 2-5 years vs. >5 years, HR = 1.8, p = 0.006); and age at initial diagnosis (> or =60 vs. <60, HR = 1.6, p = 0.01). CONCLUSIONS: Many patients with LR after CS+RT have prolonged distant disease-free survival, particularly those able to be treated with mastectomy. Patients with a noninvasive LR, longer interval to LR, or age <60 had a longer time to distant failure, second malignancy, or death than other patients.  相似文献   
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Female infertility is a worldwide problem affecting 10-15% of the population. The cause of the infertility in many cases is not known. In the present report, we demonstrate that alterations in two transmembrane structural proteins, IA-2 and IA-2beta, located in dense core secretory vesicles (DCV) of many endocrine and neuroendocrine cells, can result in female infertility. IA-2 and IA-2beta are best known as major autoantigens in type 1 diabetes, but their normal function has remained an enigma. Recently we showed in mice that deletion of IA-2 and/or IA-2beta results in impaired insulin secretion and glucose intolerance. We now report that double knockout (DKO), but not single knockout, female mice are essentially infertile. Vaginal smears showed a totally abnormal estrous cycle, and examination of the ovaries revealed normal-appearing oocytes but the absence of corpora lutea. The LH surge that is required for ovulation occurred in wild-type mice but not in DKO mice. Additional studies showed that the LH level in the pituitary of DKO female mice was decreased compared with wild-type mice. Treatment of DKO females with gonadotropins restored corpora lutea formation. In contrast to DKO female mice, DKO male mice were fertile and LH levels in the serum and pituitary were within the normal range. From these studies we conclude that the DCV proteins, IA-2 and IA-2beta, play an important role in LH secretion and that alterations in structural proteins of DCV can result in female infertility.  相似文献   
33.
The National Institute on Aging Preclinical Alzheimer's disease Workgroup (PADW) has issued a preliminary report with recommendations for classifying preclinical Alzheimer's disease (pAD) according to 3 early disease stages. Here we examine the PADW recommendations in relation to neuropathological features in a large, consecutive series of cognitively intact elderly persons, autopsied within a year after cognitive testing (n = 126 cognitively intact patients with mean age 83.7 years at death). Subjects were grouped based on a hypothetical construct correlating pathological features with PADW stages. Many cognitively intact individuals were classifiable as pAD (53/126 or 43%), as expected based on epidemiological and biomarker studies. Of these, most (48%) were in “stage 3”, which corresponds to amyloid pathology with early neurodegeneration. As with prior studies, our data indicate that the development of neocortical neurofibrillary tangles is the key pathological event that is not observed in pAD cases: Braak stages III or IV pathology are hence not truly a substrate for “intermediate likelihood” that cognitive impairment is due to Alzheimer's disease (AD). We also stress the importance of comorbid non-Alzheimer's disease brain pathologies (hippocampal sclerosis, neocortical alpha-synucleinopathy, cerebrovascular disease, and brains with hippocampal neurofibrillary tangles but no cortical amyloid plaques) that can contribute to the development of cognitive impairment, or which may serve as confounds in the application of the PADW recommendations. While the final recommendations from the PADW working group have not yet been released, this preliminary analysis provides a perspective on those recommendations from a neuropathological point of view.  相似文献   
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Cognitively intact elderly research volunteers at the University of Kentucky have been recruited, followed longitudinally, and autopsied with extensive neuropathological evaluations since 1989. To date, the cohort has recruited 1,030 individuals with 552 participants being actively followed, 363 deceased, and 273 autopsied. An extensive database has been constructed with continuous updates that include textured clinical, neuropsychological, neuroimaging, and pathological information. The history, demographics, clinical observations, and pathological features of this research cohort are described. We also explain some of the evolving methodologies and the academic contributions that have been made due to this motivated group of older Kentuckians.  相似文献   
36.
The possibility that viruses can infect the peripheral autonomic nervous system (ANS) and cause a variety of acute, chronic or recurrent diseases, including such disorders as peptic ulcer, is proposed. By altering the functional activity of autonomic neurons or by seeding the target organs of these neurons with virus, infection of the ANS may produce a broad spectrum of clinical manifestations. Whether these manifestations are anatomically circumscribed or widespread will depend upon the route by which autonomic infection is acquired as well as the character of interaction between the virus and the infected autonomic neuron. In addition, it is proposed that autonomic ganglia may serve as reservoirs of latent viruses, insuring their preservation and intermittent transmission in the human community.  相似文献   
37.
Peripheral blood leukocytes (PBL) of 41 subjects were tested for their ability to be stimulated by herpes simplex virus antigens as measured by [(3)H]thymidine incorporation and lymphokine production (i.e., lymphocyte-derived chemotactic factor and lymphotoxin). The PBL of seronegative subjects failed to respond to viral antigens as measured by stimulation or lymphokine production. In contrast, PBL from seropositive subjects without clinical lesions of herpes labialis were stimulated by herpes simplex virus antigens and produced lymphokines. PBL from seropositive patients with clinical lesions of herpes labialis also produced lymphokines, but [(3)H]thymidine incorporation was slightly depressed. These findings suggest that lymphocytes from patients with a recent herpes simplex virus infection may respond less vigorously to in vitro stimulation by herpes antigens, but our study fails to show any basic defect in the responsiveness of the lymphocytes to account for recurrent herpetic episodes.  相似文献   
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The aim of this study is to determine whether calcium and vitamin D supplementation reduces the risk of bone fractures in adult epilepsy patients. Records were obtained on 7716 patients with epilepsy prescribed antiepileptic drugs (AED) from the Veteran Affairs Hospital in Lexington, Kentucky. We performed a single center, retrospective cohort study to examine the proportion of fractures in 3303 patients on AED who took supplements compared to patients on AED not taking supplements. Patients prescribed long-term AEDs taking calcium and vitamin D were as likely to have fractures as those who did not take these supplements (11.7% vs. 9.9%, χ2 = 0.59, p = 0.44). Phenytoin use was associated with a statistically significant increased risk of fractures OR = 1.55 (1.10-2.24). Thus, in this group of patients with epilepsy on AED, bone fractures were not prevented in individuals taking calcium and vitamin D supplementation.  相似文献   
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