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91.
92.
Chondroblastic osteosarcoma of the larynx.   总被引:1,自引:0,他引:1  
Osteosarcoma of the larynx is a rare lesion. Acceptable cases in the literature are difficult to find. We report a case in which total laryngectomy was carried out for a large, obstructing mass that arose from the cricoid cartilage. We present the histologic criteria for the diagnosis of chondroblastic osteosarcoma.  相似文献   
93.
BACKGROUND AND PURPOSE: There is disagreement in the literature about the importance of sleep disruption from intensive care unit (ICU) environmental noise. Previous reports have assumed that sleep disruption is produced by high-peak noise. This study aimed to determine whether peak noise or the change in noise level from baseline is more important in inducing sleep disruption. We hypothesized that white noise added to the environment would reduce arousals by reducing the magnitude of changing noise levels. PATIENTS AND METHODS: Four subjects underwent polysomnography under three conditions: (1) baseline, (2) exposure to recorded ICU noise and (3) exposure to ICU noise and mixed-frequency white noise, while one additional subject completed the first two conditions. Baseline and peak noise levels were recorded for each arousal from sleep. RESULTS: A total of 1178 arousals were recorded during these studies. Compared to the baseline night (13.3+/-1.8 arousals/h) the arousal index increased during the noise (48.4+/-7.6) but not the white noise/ICU noise night (15.7+/-4.5) (P<0.004). The change in sound from baseline to peak, rather than the peak sound level, determined whether an arousal occurred and was the same for the ICU noise and white noise/ICU noise condition (17.7+/-0.4 versus 17.5+/-0.3 DB, P=0.65). CONCLUSIONS: Peak noise was not the main determinant of sleep disruption from ICU noise. Mixed frequency white noise increases arousal thresholds in normal individuals exposed to recorded ICU noise by reducing the difference between background noise and peak noise.  相似文献   
94.
Systolic hypertension in older persons   总被引:10,自引:1,他引:9  
Chaudhry SI  Krumholz HM  Foody JM 《JAMA》2004,292(9):1074-1080
Context  The Seventh Report of the Joint National Committee on Prevention, Detection, Evaluation, and Treatment of High Blood Pressure emphasizes the importance of systolic hypertension (SH), defined as systolic blood pressure (SBP) of at least 140 mm Hg and diastolic blood pressure of less than 90 mm Hg, in older persons (60 years). Objective  To systematically review the literature on clinical management of SH in older persons. Data Sources  We performed a MEDLINE search of English-language literature from 1966-2004 to identify reports about SH in older persons, with particular emphasis on data from randomized clinical trials. Study Selection and Data Extraction  We selected 1064 studies by using the search terms hypertension combined with the terms systole (or systolic) and aged. Data Synthesis  There is strong evidence from clinical trials to support the treatment of SH in older persons with SBP of at least 160 mm Hg. Large-scale trials to assess the value of antihypertensive therapy for older patients with SBP of 140 to 159 mm Hg have not been performed, and recommendations to treat these patients are based on observational studies that show a graded relationship of cardiovascular risk with increasing SBP. The studies most strongly support the use of thiazide diuretics and long-acting calcium channel blockers as first-line therapy to treat SH. Conclusions  Treatment of SH in older patients with SBP of at least 160 mm Hg is supported by strong evidence. The evidence available to support treatment of patients to the level of 140 mm Hg or those with baseline SBP of 140 to 159 mm Hg is less strong; thus, these treatment decisions should be more sensitive to patient preferences and tolerance of therapy.   相似文献   
95.
96.
PURPOSE: To determine whether low educational level is associated with poor functional recovery after hospitalization in older adults. METHODS: We followed 862 patients (374 with low education, defined as 相似文献   
97.
Three closely related proteins transport glutamate into synaptic vesicles for release by exocytosis. Complementary patterns of expression in glutamatergic terminals have been reported for VGLUT1 and VGLUT2. VGLUT3 shows expression by many cells not considered to be glutamatergic. Here we describe the changes in VGLUT expression that occur during development. VGLUT1 expression increases gradually after birth and eventually predominates over the other isoforms in telencephalic regions. Expressed at high levels shortly after birth, VGLUT2 declines with age in multiple regions, in the cerebellum by 14-fold. In contrast, Coexpression of the two isoforms occurs transiently during development as well as permanently in a restricted subset of glutamatergic terminals in the adult. VGLUT3 is transiently expressed at high levels by select neuronal populations, including terminals in the cerebellar nuclei, scattered neurons in the cortex, and progenitor-like cells, implicating exocytotic glutamate release in morphogenesis and development. VGLUT3 also colocalizes extensively during development with the neuronal vesicular monoamine transporter VMAT2, with the vesicular acetylcholine transporter VAChT, and with the vesicular gamma-aminobutyric acid transporter VGAT. Such coexpression occurs particularly at some specific developmental stages and is restricted to certain sets of cells. In skeletal muscle, VGLUT3 localizes to granular organelles in the axon terminal as well as in the muscle sarcoplasm. The results suggest novel mechanisms and roles for regulated transmitter release.  相似文献   
98.
Paroxysmal kinesigenic dyskinesia manifestation of hyperthyroidism   总被引:3,自引:0,他引:3  
Puri V  Chaudhry N 《Neurology India》2004,52(1):102-103
Sporadic paroxysmal kinesigenic dyskinesia (PKD) secondary to thyrotoxicosis is an extremely rare entity. A 36-year-old female presented with the features of PKD. Her investigations revealed thyrotoxicosis. Her dyskinesia did not respond to carbamazepine but remitted with the anti-thyroid drug, neomercazole. Perhaps hyperthyroidism-related PKD is a result of a metabolic disturbance of the basal ganglia circuits rather than a permanent and irreversible change.  相似文献   
99.
PURPOSE: To review the clinical features and treatment strategies for microphthalmic globes with orbital cyst. METHODS:: The clinical records of 23 patients treated for microphthalmos associated with orbital cysts were reviewed retrospectively. RESULTS: Most cases of congenital microphthalmos with orbital cysts were first noted at birth, and all were confirmed by means of computed tomography and/or ultrasonography. Six of the 23 cases were bilateral. Sixty-seven percent of bilateral and 29% of unilateral cases also had other congenital malformations. Mild microphthalmos was noted in 3 orbits, moderate in 16 orbits, and severe in 10 orbits. On the basis of clinical findings, 8 orbits were treated with enucleation and cyst excision and 15 were treated with cyst excision only. Cyst aspiration was performed on 5 orbits; 2 required aspiration and subsequent cyst excision. Twenty-six orbits had good cosmesis and 2 had acceptable cosmesis. The mean follow-up interval was 5.15 years. CONCLUSIONS: Management of microphthalmos with orbital cyst is a cosmetic issue. Cyst size, degree of microphthalmos, and general condition of the patient determine the best treatment approach.  相似文献   
100.
17 beta-estradiol induces rapid effects on cells of the immune system via plasma membrane surface receptor but the ways in which delayed signals involving intracellular receptors affect the same functions are not well understood. To study the delayed but sustained events in estradiol signaling, we have investigated macrophage Ca(2+) signaling, detected specific Ca(2+) ion channel activated and found a relationship between intracellular calcium [Ca(2+)](i) and macrophage release of reactive oxygen species (ROS) and nitric oxide (NO) during delayed 17 beta-estradiol activity. We found evidence of additional effect of estradiol on capacitative entry of Ca(2+), Ca(2+) entry through L-type channel and a direct relationship between [Ca(2+)](i) and generation of ROS and NO. This study demonstrates that 17 beta-estradiol exhibits a delayed phase of Ca(2+) influx involving L-type channel and regulates macrophage immune redox function.  相似文献   
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