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11.
12.

Background  

A substance use screening instrument was used to determine factors predictive of drinking during pregnancy. Alcohol consumption during pregnancy can lead to negative birth outcomes.  相似文献   
13.
We sought whether microdamage could rise in postmenopausal osteoporotic women on long-term bisphosphonates, as suggested by recent animal studies. We found few microcracks in iliac bone biopsies, despite a marked reduction in bone turnover. INTRODUCTION: Animal studies suggest that bisphosphonates (BPs) could increase microdamage frequency in a dose-dependent manner, caused by excessively suppressed bone turnover. However, there is limited data in humans receiving BP therapeutic doses for >3 yr. MATERIALS AND METHODS: We measured microcrack frequency and histomorphometry parameters on transiliac bone biopsies in 50 postmenopausal osteoporotic women (mean age = 68 yr) who had received BP therapy (3 on intravenous pamidronate, 37 on oral alendronate, and 10 on oral risedronate) for at least 3 yr (mean treatment duration = 6.5 yr). We compared these results with transiliac bone biopsies obtained from 12 cadavers. We used bulk staining with green calcein as a fluorochrome. The microcracks were quantified in three 100-microm-thick sections using optic microscopy and were confirmed by laser confocal microscopy. Microcrack frequency (number of microcracks/mm2 of bone tissue) was compared between treated women and controls using nonparametric tests. We also explored predictors of microcrack frequency, including age, duration of BP therapy, and activation frequency. RESULTS: Among treated women, cancellous bone microcrack frequency was low (mean, 0.13 microcracks/mm2) and did not differ significantly from that observed in controls (0.05 microcracks/mm2; p = 0.59). Of note, 54% of the treated women and 58% of the controls had no observable microcracks. There was no association between microcrack frequency and the duration of BP therapy (for microcracks/mm2 and duration, Spearman r = 0.04, p = 0.80) and between patients' ages and the number of microcracks (Spearman r = -0.09, p = 0.61). Although bone remodeling parameters were suppressed in treated women, we found no relationship between microcrack density and activation frequency (Spearman r = -0.003, p = 0.99). Also, microcrack frequency was not increased in women with prevalent vertebral fracture compared with those without fractures. CONCLUSIONS: Among postmenopausal osteoporotic women on long-term BPs, microcrack frequency in the iliac bone is low, despite a marked reduction of bone turnover.  相似文献   
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The excitatory responses of neurones in the anterior cingulate cortex of the rat to iontophoretically applied substance P (SP) are reduced by noradrenaline (NA) applied iontophoretically or released from noradrenergic pathways. In order to determine the receptor involved in this inhibitory effect we have studied the effects of a number of receptor-specific adrenergic agonists and antagonists on responses of cingulate neurones to SP in rats anaesthetized with chloral hydrate. Low iontophoretic currents (0-15 nA) of NA, adrenaline and the beta-agonist, clenbuterol, all strongly reduced responses to SP. Isoprenaline was also effective but less consistently so, although problems were experienced with its iontophoretic release from micropipettes. The alpha 1-agonists, phenylephrine and methoxamine were also able to reduce responses to SP. However, this reduction required higher iontophoretic currents (15-60 nA) and was associated with depressant effects on baseline firing rate. The alpha 2-agonist clonidine was only weakly active at high currents and this too was associated with depression of baseline firing. Similar weak effects were noted with dopamine. The inhibitory effects of NA on SP responses were convincingly blocked or reversed by the beta-antagonist, practolol, but not by the alpha 1-antagonist, prazosin. The reduction of SP responses by phenylephrine was also blocked by practolol but unaffected by prazosin. Finally, reduction of SP excitations by activation of the coeruleocortical pathway was also blocked by practolol applied iontophoretically to the cortical cells. These results are consistent with the hypothesis that the effect of NA on SP responsiveness in the cingulate cortex is mediated by beta-adrenoreceptors.  相似文献   
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The purpose of this article is to determine if any change has occurred in the role labyrinthectomy plays in the therapeutic armamentarium of members of the American Neurotologic Society. Questionnaires were sent to all members and 42% of these were returned. Analysis of the questionnaires suggests that labyrinthectomy still remains an important tool in the surgical management of vertigo, although it is less frequently employed now than 10 years ago. This seems to be the consequence of increased valuation of even minimal levels of residual hearing.  相似文献   
18.
Value of grading squamous cell carcinoma of the head and neck.   总被引:3,自引:0,他引:3  
We report a series of 3,294 patients with squamous cell carcinoma of the head and neck seen by one of us between 1963 and 1990. Two thousand and seven patients had a histologically proven and graded, but previously untreated, squamous cell carcinoma of the mucosal surfaces of the head and neck. These tumors had been graded previously by many different pathologists in many different hospitals, both in the United Kingdom and the United States, as well as continental Europe, over this period. Of the host factors both sex and age were associated with differentiation: 34% of patients less than age 50 had a well-differentiated tumor compared with 44% greater than age 50; 32% of women had a poorly differentiated tumor compared with 26% of men. General condition had no correlation with degree of differentiation. Site was closely associated with grading: well-differentiated tumors were more common in the mouth and larynx and poorly differentiated tumors in the pharynx. Furthermore, of poorly differentiated tumors, 19% arose from areas normally lined by keratinized squamous epithelium, 22% from a nonkeratinized area, 36% from respiratory epithelium, and 45% from areas normally covered by lymphoid epithelium. T stage had no significant correlation with differentiation. However, 46% of patients with poorly differentiated tumors had a nodal metastasis at presentation compared with only 28% of well-differentiated tumors. Distant metastases at presentation were found in 3.4% of poorly differentiated tumors compared with 1.8% of well-differentiated tumors. The survival fell significantly from 33% for well-differentiated tumors to 27% for poorly differentiated tumors. The recurrence rate at the primary site rose from 25% for well-differentiated tumors to 27% for poorly differentiated tumors, and recurrence in the lymph nodes rose from 26% to 30%. Both differences were just significant.  相似文献   
19.
The purpose of this investigation was to determine differences in tissue composition of symptomatic and asymptomatic disc herniations as reflected in T1 and T2 relaxation times (quantitative magnetic resonance investigation of the lumber spine. The longitudinal and transverse magnetic rlaxation times (T1 and T2, respectively) were calculated from a set of 20 images obtained with five single-slice/multi-echo sequences at different repetition time values on a commercial whole-body system (1.5 T). Twenty-two symptomatic and asymptomatic disc herniations could be matched according to age, gender, disc level, and the extent of herniation (protrusion or extrusion) and were compared with regard to T1 and T2 relaxation times. Symptomatic disc herniations exhibited significantly (pT1 < 0.04 and pT2 < 0.003) shorter T1(ΔT1:–182.1 milliseconds, ?15%) and T2(ΔT2: ?11.0 milliseconds, ?21%) relaxation times than matched asymptomatic herniations. Symptomatic disc herniations also exhibited more advanced disc degeneration as graded by Pearce's criteria (p < 0.01). These results suggest that symptomatic and morphologically matched asymptomatic disc herniations differ with regard to disc matrix composition.  相似文献   
20.
OBJECTIVE: Methods employed previously to analyze the secretory behavior of rodent Kupffer cells (KC) were used to examine the human KC's secretory response to lipopolysaccharide (LPS). SUMMARY BACKGROUND DATA: As the resident hepatic macrophage, the KC resides at the interface between the portal and systemic circulations. Consequently, this cell may play an integral role in the immune response to antigens and bacteria in the sinusoid. Study of cytokine production by the KC has relied predominantly on the rat as the source of these cells. Whether human KCs respond similarly to rat KCs after LPS stimulation has been a matter of speculation. METHODS: Kupffer cells obtained from seven human livers were tested under conditions identical to those used to study rat KCs. Kupffer cells rested for 12 hours after isolation were stimulated with LPS (2.5 micrograms/mL). Arginine concentration in the culture medium varied from 0.01 to 1.2 mM. To examine the role of eicosanoids, parallel culture wells received indomethacin (10 microM). Culture supernatants were assayed for interleukin-1 (IL-1), interleukin-6 (IL-6), tumor necrosis factor-alpha (TNF-alpha), transforming growth factor-beta (TGF-beta), prostaglandin E2 (PGE2), and nitric oxide. RESULTS: Similar to the rat KC, LPS-stimulated human KCs released IL-1, IL-6, TNF-alpha, TGF-beta, and PGE2. However, unlike rat KCs, nitric oxide could not be detected, regardless of whether the human KCs were exposed to LPS, interferon-gamma (INF-gamma), or LPS + IFN-gamma. Similar to rat KCs, indomethacin prevented PGE2 release while significantly upregulating TNF-alpha, IL-1, and IL-6, but not TGF-beta, consistent with an autoregulatory control of eicosanoids over proinflammatory cytokines. As has been shown in the rat, physiologic levels of L-arginine (0.01 mM) significantly enhanced LPS-induced PGE2 secretion relative to the response in medium containing standard L-arginine concentration (1.2 mM); however, unlike the rat KC, the human's cytokine response to LPS was not downregulated by this enhanced PGE2 release. CONCLUSIONS: Although many functional features are shared by rat and human KCs, significant differences do exist. Such discrepancies reinforce the need to proceed with caution when generalizing from the results obtained in other species to human physiology.  相似文献   
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