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991.
992.
Previously, we observed that olfactory stimulation with scent of lavender oil (SLVO) suppressed sympathetic nerve activities and elevated gastric vagal (parasympathetic) nerve activity (GVNA), decreased plasma glycerol concentration and body temperature, and enhanced appetite in rats. Here, we further showed that olfactory stimulation with SLVO lowered renal sympathetic nerve activity (RSNA) and blood pressure (BP) and elevated GVNA in urethane-anesthetized rats. Olfactory stimulation with linalool, a component of lavender oil, also elicited decreases in RSNA and BP and an increase in GVNA in urethane-anesthetized rats. Anosmia induced by pretreatment of the nasal cavity by application of ZnSO4 eliminated the effects of both SLVO and scent of linalool on RSNA, GVNA and BP. Furthermore, intracerebroventricular administration of thioperamide, a histaminergic H3-antagonist, abolished the suppression of RSNA and BP as well as the elevation of GVNA mediated by both SLVO and scent of linalool. Finally, bilateral lesions of the hypothalamic suprachiasmatic nucleus (SCN) eliminated RSNA and BP suppression and the elevation of GVNA due to SLVO or linalool. Thus, it was concluded that scent of lavender oil and its active component, linalool, affects autonomic neurotransmission and reduces blood pressure through the central histaminergic nervous system and the SCN.  相似文献   
993.
This study aims to elucidate the feasible geometry of the scaffolds in bone and periodontal tissue engineering. Several biomaterials with different geometries are compared in terms of their patterns of ectopic BMP-induced chondrogenesis and osteogenesis. The materials include a honeycomb-shaped hydroxyapatite (HCHAP) with different tunnel sizes, a laser-perforated collagen membrane (LPM), and CPSA bioglass fibers. Implanted pellets were removed at 1-4 weeks and analyzed for bone and cartilage formation histologically and biochemically. Porous particles of hydroxyapatite (PPHAP), porous blocks of hydroxyapatite (PBHAP), and LPM did not induce detectable cartilage formation. In straight tunnel structures with various diameters in honeycomb-shaped hydroxyapatite (HCHAP), tunnels with smaller diameters (approximately 0.1 mm) induced cartilage followed by bone formation, while one with a larger diameter (0.35 mm) directly induced bone formation within the tunnels. It is concluded that the "vasculature-inducing geometry" of the carrier as an ECM is crucially important for osteogenesis.  相似文献   
994.
Previously, we observed that olfactory stimulation with scent of grapefruit oil (SGFO) or scent of lavender oil (SLVO) affected, elevated or lowered brown adipose tissue temperature (BAT-T) in conscious mice, respectively. In the present study, to test the day-night difference in the actions of olfactory stimulations, we examined the responses of BAT-T and body temperature (BT) measured as the abdominal temperature to SGFO or SLVO during day-time at 14:00 and night-time at 2:00 in conscious rats. In the light period, BAT-T and BT were suppressed after SLVO and elevated after SGFO whereas in the dark period, these parameters remained unchanged with olfactory stimulations. Bilateral lesions of the hypothalamic suprachiasmatic nucleus (SCN) eliminated the effects of olfactory stimulations with SGFO and SVLO on BAT-T and BT. Moreover, sympathetic nerve activity innervating brown adipose tissue (BAT-SNA) changes after SGFO or SLVO were abolished in SCN-lesioned rats. Thus, we concluded that there is day-night difference in the effects of SGFO or SLVO on BAT-T and BT, and that the SCN might be involved in these effects.  相似文献   
995.
Parafibromin is a protein encoded by the hyperparathyroidism 2 oncosuppressor gene and its downregulated expression is involved in pathogenesis of parathyroid carcinomas. To clarify the roles of parafibromin expression in tumourigenesis and progression of gastric carcinomas, it was examined by immunohistochemistry (IHC) on tissue microarray containing gastric carcinomas (n = 508), adenomas (n = 45) and gastritis (n = 49) with a comparison of its expression with clinicopathological parametres of carcinomas. Gastric carcinoma cell lines (MKN28, AGS, MKN45, KATO-III and HGC-27) were studied for parafibromin expression by IHC and western blot. Parafibromin expression was localised in the nucleus of gastric epithelial cells, adenoma, carcinoma cells and cell lines. Its expression was gradually decreased from gastritis to gastric carcinoma, through gastric adenomas (p < 0.05) and inversely correlated with tumour size, depth of invasion, lymphatic invasion, lymph node metastasis and Union Internationale Contre le Cancer (UICC) staging (p < 0.05) but not with sex or venous invasion (p > 0.05). Parafibromin was strongly expressed in older carcinoma patients compared with younger ones (p < 0.05). There was stronger positivity of parafibromin in intestinal-type than diffuse-type carcinomas (p < 0.05). Univariate analysis indicated cumulative survival rate of patients with positive parafibromin expression to be higher than without its expression (p < 0.05). Multivariate analysis showed that age, tumour size, depth of invasion, lymphatic invasion, lymph node metastasis, UICC staging and Lauren’s classification but not sex, venous invasion or parafibromin expression were independent prognostic factors for carcinomas(p < 0.05). Downregulated parafibromin expression possibly contributed to pathogenesis, growth, invasion and metastasis of gastric carcinomas. It was considered as a promising marker to indicate the aggressive behaviours and prognosis of gastric carcinomas.  相似文献   
996.
Chondroadherin, which is reported to be synthesized by chondrocytes and to promote their attachment, was purified from bovine bone. It was a minor component of bone organic matrix, and was present in the 4 M guanidine extract of demineralized bone. Chondroadherin promoted attachment of osteoblastic cells to solid-state substrates, and bound to collagen. Binding of chondroadherin to collagen was significantly higher than that of osteonectin or decorin. These findings imply that chondroadherin may play a role in maintaining bone cells on the collagen matrices of bone.  相似文献   
997.
Ipriflavone and calcium supplements are used in the treatment of osteoporosis. However, the effect of ipriflavone in combination with high-dose calcium supplements (1 g/day) on bone metabolism in elderly osteoporotic women is still a matter of controversy. Enrolled in this study were 22 women over 70 years of age diagnosed as having involutional osteoporosis. The patients were randomly assigned to treatment with either ipriflavone plus calcium or with calcium supplements only for 6 months. Biochemical markers of bone metabolism and bone mass of the hand were determined at baseline and at 6 months. Serum parathyroid hormone, serum osteocalcin, serum alkaline phosphatase, and the urinary hydroxyproline/creatinine ratio decreased in both groups. These decreases were greater in the ipriflavone plus calcium supplement group than in the calcium supplement only group. Serum calcitonin increased in the ipriflavone plus calcium supplement group. Metacarpal index and metacarpal bone mineral density did not change in either group. These findings suggest that treatment with ipriflavone plus calcium supplements may inhibit bone resorption and modulate bone turnover in elderly osteoporotic women and may be more effective than calcium supplements alone.  相似文献   
998.
The role of calmodulin (CaM) in neuromuscular transmission in the rat diaphragm was electrophysiologically investigated using a microelectrode technique with two different CaM inhibitors, trifluoperazine (TFP) and N-(6-aminohexyl)-5-chrolo-1-naphthalene-sulfonamide HCl (W-7). These inhibitors in the perfusate decreased the amplitude of miniature endplate potentials and increased the frequency dose dependently without any changes occurring in the resting membrane potentials. These effect were abolished in a Ca2+-free perfusate. The acetylcholine (ACh) quantal size and content were not affected by the reagents. The effects of TFP and W-7 were thought to result from their specific inhibition of calmodulin. It is suggested that accumulated intracellular Ca2+ and cyclic AMP, due to inhibition of calmodulin, had enhanced the frequency of spontaneous ACh release from the nerve terminal, and the decrease in the amplitude might be attributed to inhibition of the postsynaptic action of CaM.  相似文献   
999.
An unusual case of primary reticulosis of the bone marrow in a 67-year-old female has been described. Pathological-anatomical characteristics of the present case are as follows; 1) Primary non-destructive proliferation of neoplastic reticulum cells or their variants, confined to the systemic bone marrow. Metastatic foci were noted in several areas where extramedullary hematopoiesis occurred. 2) Cytologically, neoplastic cells resemble atypical plasmacytic cells. No active phagocytosis was noted in neoplastic cells. 3) Histologically a significant increase in reticulin flbers was observed closely associated with proliferating cells. 4) Electron-microscopically these cells showed developed endoplasmic reticula but were distinguishable from myeloma cells by their irregular cytoplasmic border, which became frequently obscure, and by the presence of a desmosome-like structure. 5) These cells showed a negative immunofluorescent reaction to all types of human immunoglobulin classes. The morphological characteristics of these cells distinguished the disorder from poorly differentiated myelomatosis.  相似文献   
1000.
To enhance the stability in vivo, new derivatives of cytogenin were synthesized, and their biological activity and stability in mice were estimated. 2-(8-Hydroxy-6-methoxy-1-oxo-1H-2-benzopyran-3-yl)propionic acid (NM-3) was found to be the most stable among them. It modified collagen-induced arthritis in mice. It also showed potent anti-angiogenic activity in a mouse dorsal air sac assay.  相似文献   
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