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71.
We have previously found that oral or intravenous (i.v.) administration of the polysaccharide fraction PB-2, extracted from the lichen Flavoparmelia baltimorensis, facilitated the induction of long-term potentiation (LTP) in the dentate gyrus (DG) in vivo. In this study, the mechanism underlying the effect of PB-2 on the induction of LTP was investigated in the DG of anesthetized rat focusing on the contribution of the interleukin-1 (IL-1) receptor and the adrenaline beta-receptor. An i.v. injection of IL-1ra (10(-9) g/kg), an antagonist of the IL-1 receptor, had no effect on the basal response in the DG; however, this treatment augmented the enhancement of LTP induced by a single i.v. injection of PB-2 (10(-3) g/kg). This potentiating effect was also observed following intracerebroventricular (i.c.v.) injection of IL-1ra (10(-15)-10(-11) g). An i.v. injection of IL-1beta (3.5 x 10(-15)-3.5 x 10(-9) g/kg) inhibited the induction of LTP, which was diminished by the previous application of IL-1ra. These results suggest that the activation of the IL-1 receptor induces the suppression of LTP in PB-2-treated rats, and that endogenous IL-1beta contributes to the IL-1 receptor activation. An i.c.v. infusion of metoprolol (7.5 x 10(-6) g), an antagonist of the adrenaline beta(1)-receptor, attenuated the enhancement of LTP induced by an i.v. injection of PB-2. These results suggest that PB-2 has two different effects on the LTP, an enhancing effect and an inhibiting one, and that it exhibited the significant enhancing effect on the LTP as a total balance of these effects.  相似文献   
72.
A duodenum-preserving pancreatic head resection technique was first reported in 1980, but the indications have been limited to benign pancreatic disease as it involves a subtotal pancreatic head resection. In 1988 we detailed a duodenum-preserving total pancreatic head resection (DPTPHR) technique. This procedure involved a total pancreatic head resection and as such expanded the indications for this approach to include tumorigenic masses. The original method involved closure of the proximal pancreatic duct and an anastomosis of the pancreatic duct of the distal pancreas to a newly created small hole in the duodenum (we termed this a "pancreatoduodenostomy"). Our current technique involves a duct-to-duct anastomosis of the proximal pancreatic duct and the distal pancreas to better preserve anatomic structure. DPTPHR was performed in 26 patients from 1988 to 2002, including 12 cases of DPTPHR with pancreatoduodenostomy and 14 cases of DPTPHR with pancreatic duct-to-duct anastomosis. No differences were observed between the two methods with respect to operative time or blood loss during surgery. Postoperatively, there was one case of cholecystitis and one case of pancreatitis in a patient who underwent a pancreatoduodenostomy; both of these patients were treated conservatively with curative intent. No complications were observed in the group undergoing duct-to-duct anastomosis. The advantage of duct-to-duct anastomosis is that the pancreatic head is totally resected, thus allowing removal of neoplastic disease such as an intraductal papillary mucinous tumor and also therapy for chronic pancreatitis. A key benefit of this procedure is that sphincter function of the duodenal papilla is preserved permitting drainage of pancreatic/bile juice into the duodenum, preserving a more physiologic state than is the case after a pancreatoduodenostomy. Supported in part by a Grant-in-Aid for Scientific Research (63480311) from the Ministries of Education, Science, and Culture of Japan.  相似文献   
73.
74.
The purpose of the present study was to understand the mechanisms of action of diquafosol, a stable derivative of uridine 5'-triphosphate, on Cl(-) transport across the isolated rabbit conjunctiva. Rabbit conjunctivas were isolated and mounted in a modified Ussing chamber. Under short-circuit conditions, the effects were determined of mucosal (tear) side diquafosol application on the short-circuit current (Isc). Diquafosol rapidly and dose-dependently increased the Isc at concentrations ranging from 0.1 to 968 microM when added to the mucosal side of the conjunctiva. In the absence of the serosal Cl(-), the Isc induced by 10 microM diquafosol was substantially reduced. On the contrary, in the absence of mucosal side Na(+), the diquafosol-induced increases in Isc were unchanged. Following 45-min preincubation, the P2Y(2) antagonist suramin inhibited the diquafosol-induced increases in the Isc whereas the P2Y(1) antagonist pyridoxal-phosphate-6-azophenyl-2'4'-disulfonic acid had no effect. These studies suggest that diquafosol stimulates net Cl(-) secretion from the serosal to the mucosal side via stimulation of P2Y(2) receptors in the rabbit conjunctiva.  相似文献   
75.
A 46-year-old woman presented to our hospital with a rapidly growing lump in her right breast. Fine-needle aspiration (FNA) cytology and core needle biopsy of the mass revealed many epithelioid cells admixed with multinucleated Langhans-type giant cells, neutrophils, lymphocytes, and stromal cells, leading to a diagnosis of granulomatous mastitis. Mammography and ultrasonography provided little information for differentiating between granulomatous mastitis and carcinoma. This patient was successfully treated with low dose and short period of corticosteroid therapy.  相似文献   
76.
Conclusions The pathophysiology of essential hypertension is not homogeneous; it is thought to consist of multifactorial disorders. Therefore, an appropriate first-line antihypertensive drug should be selected according to the pathophysiologic state of this disease in each patient. In this article, preferable first-line antihypertensive drugs were discussed from a clinical, general practice viewpoint on the basis of the pathophysiologic characteristics of patients with benign essential hypertension. The usefulness of some low-dose combination therapies was also discussed from the same viewpoint.  相似文献   
77.
1. Using two murine strains, ICR/Jcl and senescence-accelerated-prone inbred mouse 1 (SAMP1), age-associated changes in urine indices (e.g. urine volume, creatinine contents, contents of alpha 1-microglobulin (alpha 1M) and ulinastatin (UT) and the relation of urinary contents of alpha 1M and UT were investigated. 2. Sex-related differences in the indices were not observed in ICR nor in SAMP1 mice. 3. Urine indices per 24 h of ICR mice at 6 and 14 months of age were higher than those at 3 months of age, although indices of SAMP1 mice did not change with ageing. Urinary contents of alpha 1M and UT in ICR mice at 6 and 14 months of age were higher than those in SAMP1 mice. However, contents of alpha 1M and UT expressed as the contents per creatinine did not differ between these two strains. 4. In the relation between urinary contents of alpha 1M and UT, a positive correlation was displayed both in ICR and SAMP1 mice, and the regression slope did not significantly differ with ageing in these two strains. 5. These results suggest that ageing per se is not a factor which affects the relation of urinary contents of alpha 1M and UT.  相似文献   
78.
The principal management of acute cholecystitis is early cholecystectomy. However, percutaneous transhepatic gallbladder drainage (PTGBD) may be preferable for patients with moderate (grade II) or severe (grade III) acute cholecystitis. For patients with moderate (grade II) disease, PTGBD should be applied only when they do not respond to conservative treatment. For patients with severe (grade III) disease, PTGBD is recommended with intensive care. Percutaneous transhepatic gallbladder aspiration (PTGBA) is a simple alternative drainage method with fewer complications; however, its clinical usefulness has been shown only by case-series studies. To clarify the clinical value of these drainage methods, proper randomized trials should be done. This article describes techniques of drainage for acute cholecystitis.  相似文献   
79.
Lysichiton camtschatcense is a well-known plant in Japan where it has been used as a traditional medicine by the “Ainu” people for the treatment of acute nephritis. It is presumed that L. camtschatcense has an inhibitory effect against nephritis caused by reactive oxygen species (ROS) owing to its antioxidant activities. Consequently, the antioxidant effect of L. camtschatcense extracts was assessed against Fe2+/ascorbic acid (AsA)-induced lipid peroxidation in rat kidney and brain homogenates. The antioxidant effect of the chloroform extract (CE) was more potent than that of the methanol extract (ME) for both homogenates. The antioxidant effect of both extracts was similar to those of α-tocopherol, a lipid-soluble antioxidant, and glutathione (GSH), a water-soluble antioxidant, which were used as reference compounds. Although CE showed a low radical-scavenging effect for superoxide anion radicals (O2·−) and 1,1-diphenyl-2-picrylhydrazyl (DPPH) radicals, assessed by using an electron spin resonance (ESR) method, hydroxyl radicals (·OH) were markedly scavenged by more than 80%. On the other hand, ME showed more significant scavenging effect for DPPH radicals and O2·− than CE. These results suggest that the inhibitory effects of the L. camtschatcense extract on lipid peroxidation in rat kidney and brain are based on its high radical-scavenging effect against ·OH, O2·−, and lipid-derived radicals generated from the cell membrane.  相似文献   
80.
Mediastinal teratomas are typically benign and asymptomatic, but they undergo sudden enlargement or rupture into neighboring organs in some patients owing to intratumoral hemorrhage, leading to serious complications. We report the case of a mediastinal mature teratoma that was discovered because of the sudden onset of chest pain accompanied by elevated preoperative serum CA19-9 levels. The patient was a 43-year-old man who experienced sudden chest pain and was brought to hospital in an ambulance. Chest radiography and computed tomography revealed a mediastinal tumor and a serum CA19-9 level that was elevated to 4377 U/ml. The tumor comprised soft tissue, fluid, and cystic components. The histological diagnosis was mature teratoma with peritumoral bleeding. Most epithelial components, including squamous epithelium and similar components in the bronchi, showed positive results for CA19-9 on immunohistological examination. The postoperative course was uneventful, and serum CA19-9 levels normalized.  相似文献   
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