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91.
Barrett's esophagus (BE) is a consequence of gastroesophageal reflux disease and is predisposed to esophageal adenocarcinoma (EAC). EAC is an exemplar model of inflammation‐associated cancer. Glucocorticoids suppress inflammation through glucocorticoid receptor (GR) and serum‐ and glucocorticoid‐induced kinase‐1 (Sgk1) expressions. Therefore, we immunolocalized GR and Sgk1 in EAC and the adjacent BE tissues and studied their association with clinical disease course in 87 patients with EAC who underwent surgical resection (N = 58) or endoscopic submucosal dissection (N = 29). Low GR and Sgk1 expressions in adjacent BE tissues were associated with adverse clinical outcomes (P = 0.0008 and 0.034, respectively). Patients with low Sgk1 expression in EAC cells exhibited worse overall survival (P = 0.0018). In multivariate Cox regression analysis, low GR expression in the adjacent nonmalignant BE tissues was significantly associated with worse overall survival (P = 0.023). The present study indicated that evaluation of GR and Sgk1 expressions in both the EAC cells and adjacent nonmalignant BE tissues could help to predict clinical outcomes following endoscopic and surgical treatments. In particular, the GR status in BE tissues adjacent to EAC was an independent prognostic factor.  相似文献   
92.
Hereditary hypouricemia is a rare disorder characterized by extremely low serum uric acid levels caused by excessive urinary excretion due to an inherited tubular defect in urate handling. Exercise-induced acute kidney injury (AKI) is the main complication of this disorder, though AKI may also be induced by other factors. A 7-month-old boy with hereditary hypouricemia developed AKI associated with severe dehydration caused by rotavirus gastroenteritis. He also showed severe hypernatremia and metabolic acidosis and received continuous renal replacement therapy for 3 days. He showed no signs of hydronephrosis or urolithiasis. However, hypouricemia was noted when his renal function recovered (serum uric acid <0.6 mg/dl). Analysis of the urate transporter 1 gene revealed a homozygous nonsense mutation in exon 4 (c.774G > A, p.W258X). Both parents were heterozygous for the mutation and his younger brother was later determined to have severe hypouricemia (0.6 mg/dl). Conclusion: Uric acid is an essential factor for scavenging oxidative stressors. In this patient, severe dehydration may have directly caused pre-renal AKI, but susceptibility to oxidative stressors under severe dehydration, as well as exercise, may also contribute to AKI. Careful attention should be paid to dehydration, especially in young children, to avoid the development of AKI in patients with hereditary hypouricemia.  相似文献   
93.
The present study was initiated to produce an antiserum to phenytoin with high specificity and sensitivity which would be suitable not only for determination of blood phenytoin concentration but also for induction of a hypersensitivity reaction to phenytoin in experimental animals. p-Aminophenytoin was synthesized and identified by means of IR, 1H-NMR and mass spectroscopy. BSA-phenytoin conjugate was prepared by using p-aminophenytoin, BSA and, as a coupling reagent, glutaraldehyde. Satisfactory response to immunization was achieved at a 9.8:1 molar ratio of p-aminophenytoin to BSA. The antiserum obtained from rabbits immunized with BSA-phenytoin conjugate exhibited practically no cross-reactivity with either phenytoin metabolites or other anti-epileptic drugs, indicating that this antiserum provides sufficiently high specificity. In our experiments, the lower limit for detecting phenytoin was 2 ng using RIA, whereas 200 ng was the minimum amount detectable by HPLC. Thus, by a difference of two orders of magnitude, the present RIA method shows a much higher sensitivity than that of HPLC, though we found a good correlation of simultaneous determinations of serum phenytoin between the two methods. Reproducibility of phenytoin determination in plasma was confirmed by calculating the coefficient of variance. The values were less than 10%.  相似文献   
94.
Remarkable swelling of the foot pad was induced in guinea pigs sensitized with BSA-phenytoin by challenging with BSA-phenytoin or EA-phenytoin. Forty-eight hours after local injection of a mixture of exudate cells obtained from the abdominal cavity of sensitized guinea pigs. and BSA (EA)-phenytoin, both erythema and induration developed at the injection sites in normal guinea pigs. At the sites exhibiting these skin reactions, an exudation of mononuclear leukocytes was noted. In addition, macrophages obtained from the abdominal cavity of phenytoin-sensitized animals showed a low migration index in the presence of phenytoin. When phenytoin was administered to rats (p.o.), large amounts of the compound were detected in the gingiva and there was a good correlation between the tissue and serum phenytoin concentrations. These findings indicate that the etiology of gingival hyperplasia produced by chronic administration of phenytoin may be related in some way to a delayed-type hypersensitivity induced by the drug.  相似文献   
95.
J-104132 [(+)-(5S,6R, 7R)-2-butyl-7-[2-((2S)-2-carboxypropyl)-4-methoxyphenyl]-5-(3, 4-methylenedioxyphenyl)cyclopenteno[1,2-b]pyridine-6-carboxylic; also referred to as L-753,037] is a potent, selective inhibitor of ETA and ETB endothelin (ET) receptors (e.g., Ki: cloned human ETA = 0.034 nM; cloned human ETB = 0.104 nM). In both ligand-binding and isolated tissue preparation protocols, the inhibition of ET receptors with J-104132 is reversible and competitive. In vitro, J-104132 is a potent antagonist of ET-1-induced accumulation of [3H]inositol phosphates in Chinese hamster ovary cells stably expressing cloned human ETA receptors (IC50 = 0.059 nM), ET-1-induced contractions in rabbit iliac artery (pA2 = 9.70) and of BQ-3020-induced contractions in pulmonary artery (pA2 = 10.14). J-104132 is selective for ET receptors because it had no effect on contractions elicited by norepinephrine or KCl in the vascular preparations. The in vivo potency of J-104132 was assessed using challenges with exogenous ET-1. In conscious mice, 5 nmol/kg i.v. ET-1 causes death. Pretreatment with J-104132 prevents the lethal response to ET-1 when administered i.v. (ED50 = 0.045 mg/kg) or p.o. in fed animals (ED50 = 0.35 mg/kg). In conscious, normotensive rats, pressor responses to 0.5 nmol/kg i.v. ET-1 are inhibited by J-104132 after i.v. (0.1 mg/kg) or p.o. (1 mg/kg) administration. In anesthetized dogs, ET-1 was administered directly into the renal artery or brachial artery to generate dose-response (blood flow) curves, and the inhibitory potency of J-104132 (i.v. infusion) was quantified. J-104132 produced greater than 10-fold shifts in the ET-1 dose-response curves at 0.03 mg/kg/h (renal) and 0.3 mg/kg/h (brachial). Oral bioavailability of J-104132 in rats was approximately 40%. These studies indicate that J-104132 is a selective, potent, orally active antagonist of both ETA and ETB receptors and is an excellent pharmacological tool to explore the therapeutic use of a mixed ETA/ETB receptor antagonist.  相似文献   
96.
97.
Recently, we found N 1,N 8-diacetylspermidine (Ac2Spd) and N 1,N 12-diacetylspermine (Ac2Spm) in human urine, and noted that their amount increased significantly in patients with urogenital malignancies. Previous findings that simultaneous reference to these diacetylpolyamines is useful in distinguishing cancer patients from healthy persons were confirmed by more recent analytical data on urine samples from several cancer patients. Further examination revealed that urinary Ac2Spm and Ac2Spd tended to decrease when cancer patients were treated and entered partial remission. In cases where the Ac2Spm and Ac2Spd levels were normal or near-normal after treatments, the prognosis of the patients was generally good. In contrast, when their level remained far above the normal limits after apparently effective treatment, the prognosis of the patients was poor. When a patient is in remission for more than 3 years, urinary levels of both Ac2Spm and Ac2Spd are stabilized and stay below the normal limits, with rare exceptions. The recurrence of a cancer as well as the complication of a second one during the period of follow-up examination was accompanied by elevation of urinary diacetylpolyamines. These observations indicate that urinary Ac2Spm and Ac2Spd are useful as prognostic indicators after treatment and during follow-up examination of cancer patients. Received: 27 March 1997 / Accepted: 15 July 1997  相似文献   
98.
Histoplasmosis caused by Histoplasma capsulatum is found worldwide. Japan is known to be non-endemic area. Progressive disseminated histoplasmosis (PDH) is a severe form of histoplasmosis. We report a case of PDH in a 54-year-old male who was not immunocompromised. His last travel history to an endemic region was 2 years before onset. He was diagnosed as histoplasmosis by 18S rRNA-PCR from serum and ascites and immunodiffusion test. We treated him with parental liposomal amphotericin B for 2 weeks then changed to oral itraconazole, which was continued for 6 months. Rigorous work up, including HIV status, lymphocyte counts, and adrenal function did not reveal any evidence of immunosuppression of the patient. Our case suggests that PDH can occur in immunocompetent patients as previously described, and must be included in the differential diagnoses if presentation is consistent. In addition, the skills of travel history taking are emphasized.  相似文献   
99.
We examined the antibacterial effects of cocoa on periodontal pathogenic bacteria, including Porphyromonas gingivalis, Fusobacterium nucleatum and Prevotella intermedia, compared with its effects on indigenous oral streptococci. A colony-forming unit (CFU) assay in the presence and absence of 1.0% and 3.0% (w/v) cocoa revealed that the growth of periodontal pathogenic bacteria was significantly suppressed by cocoa in concentration- and incubation time-dependent manners, although cocoa had no effect on the growth of indigenous streptococci. Methanol- and ethanol-extractable fractions from cocoa were also subjected to the CFU assay to determine and characterize the component (s) responsible for these effects. Fractions containing mainly cocoa polyphenols showed antibacterial effects. After treatment with polyvinylpolypyrrolidone, an absorbent of polyphenols, the methanol-extractable fraction lost its effect. These results suggest that cocoa has significant antibacterial effects against periodontal pathogenic bacteria and that polyphenols are responsible.  相似文献   
100.
Background  The Japanese severity score (JSS) for acute pancreatitis was revised in 2008. As special therapies for severe acute pancreatitis (SAP), continuous regional arterial infusion of protease inhibitor and antibiotics (CRAI) and enteral nutrition (EN) are now utilized in Japan. We investigated the usefulness of the new JSS and the indications for CRAI and EN based on the new JSS. Methods  We assessed the new JSS in 138 patients with SAP according to the previous Japanese criteria. Usefulness of the new JSS for the prediction of mortality rates was compared with conventional scoring systems by receiver-operator characteristic curve analysis. We analyzed the relationship between the new JSS and prognosis in patients with and without CRAI and EN, respectively. Results  Forty-five patients (33%) were assessed as having mild acute pancreatitis, and 93 patients (67%) were assessed as having SAP. Their mortality rates were 7 and 40%, respectively. The area under the curve for the prediction of mortality rates with the new JSS was 0.822 and was the highest among conventional scoring systems. In patients with new JSS ≥ 6, the mortality rate was lower in patients with CRAI than in patients without CRAI (P = 0.129). In patients with new JSS ≥ 4, the mortality rate was lower in patients with EN than in patients without EN (P = 0.016). Conclusions  The new JSS is useful and easier to use for the prediction of prognosis compared to the conventional scoring systems. EN was effective in reducing the mortality rate in patients with a new JSS ≥ 4.  相似文献   
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