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961.
INTRODUCTION: The occurrence of organ failure following thermal injury, despite restoration of hemodynamic parameters and urine output during resuscitation, has led to efforts to measure end-organ perfusion. The purpose of this 24-h study was to evaluate the utility of gastrointestinal (GI) tonometry during burn shock and resuscitation. METHODS: Male swine (n=11, 23.3+/-0.9 kg) were anesthetized with ketamine and propofol. A 70% full thickness burn was caused by immersion in 97 degrees C water for 30 s. Resuscitation with lactated Ringer's, 4 ml/kg/% burn, was begun at hour 6 and titrated to urine output (UO). Arterial blood gases and pulmonary artery catheter data were measured every 6 h. Gastric and ileal regional PCO(2) (PrCO(2)) were measured continuously by air tonometry, and the gastric and ileal intramucosal pH (pHi) and PCO(2) gap (PrCO(2)-PaCO(2)) were calculated every 6 h. RESULTS: Gastric pHi, ileal PrCO(2), ileal pHi, and ileal PCO(2) gap (but not gastric PrCO(2) or PCO(2) gap) all decreased with shock and were restored to baseline levels by resuscitation. Changes in ileal PrCO(2) were of greater magnitude and demonstrated decreased variability than those in gastric PrCO(2). CONCLUSIONS: In this model, ileal tonometry outperformed gastric tonometry during burn shock and resuscitation.  相似文献   
962.
Esophageal bypass with a gastric tube and a cardiostomy is a method recently devised for malignant esophagorespiratory fistula. This method separates completely the alimentary and respiratory tracts. Four patients underwent these procedures. No operative deaths occurred, nor was there any anastomotic leakage or disruption of the excluded esophagus. The average survival time was 7 months. However, all patients were allowed to consume food orally up to the last moment of life. This bypass procedure is simple and safe to perform, and is thus a feasible treatment choice for patients with such fistulas.  相似文献   
963.
BACKGROUND: Portal or splenic vein thrombosis (PSVT) is a common disorder after laparoscopic splenectomy (LS). Splenomegaly is a well-known risk factor for PSVT. However, no treatment strategy for PSVT has been established. METHODS: Thirty-three consecutive patients who had undergone LS and postoperative imaging surveillance were examined. PSVT was classified according to the site of thrombosis. We evaluated patient background, operative factors, and clinical symptoms. RESULTS: Spleen weight of patients with PSVT (n = 17, median 218 g) was greater than that of patients without PSVT (n = 16, median 101 g). Seven patients developed thrombosis involving the entire splenic vein (total splenic vein thrombosis), and 4 of them had clinical symptoms (fever >38 degrees C and/or abdominal pain). The incidence of clinical symptoms was significantly more frequent in patients with than without total SVT. Operation time, blood loss, and spleen weight were also significantly greater in patients with total SVT. Multiple logistic regression analysis demonstrated spleen weight was the strongest predictor of PSVT and total SVT. CONCLUSION: Patients with total SVT have greater risk factors for PSVT and frequently have clinical symptoms. They are candidates for anticoagulation therapy.  相似文献   
964.
The authors report a case of a neuroendocrine tumor of the rectum. A 57-year-old man was revealed to have a large tumor of the rectum with invasion to the urinary bladder and seminal capsule. After resection, the tumor was revealed to be composed of neuroendocrine cells. Adjuvant chemotherapy using cisplatin and camptothecin-11 was completed, and the patient was without recurrence 6 months after surgery.  相似文献   
965.
A platelet aggregation inhibitor, named snake venom platelet aggregation dissociator (SV-PAD)-1, with a dissociative reaction of ADP-induced platelet aggregation, was purified from the venom of Protobothrops elegans (Sakishima-habu) by gel-filtration employing Sephadex G-100, and ion-exchange chromatographies using DEAE-Sepharose Fast Flow, CM-Sepharose Fast Flow, and Mono S. By this procedure, about 1.5 mg of purified protein was obtained from 1.0 g of P. elegans venom. The purified protein showed a single protein band and the molecular weight was about 110 kDa on sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) under reducing conditions. The pI of purified protein showed four-bands of 7.7, 7.8, 7.95, and 8.15. This protein strongly inhibited ADP-induced platelet aggregation in rabbit platelet-rich plasma (PRP), and its IC50 was about 58 nM. It inhibited ristocetin-induced platelet aggregation in rabbit PRP (IC50: 100 nM), but hardly blocked collagen-induced platelet aggregation. This protein promptly dissociated platelet aggregation in rabbit PRP stimulated by high-concentration ADP.  相似文献   
966.
We have previously found that both CaMKII-mediated phosphorylation and calmodulin (CaM) binding to the channels are required for maintaining basal activity of the Cav1.2 Ca2+ channels. In this study, we investigated the hypothetical CaMKII phosphorylation site on Cav1.2 that contributes to the channel regulation. We found that CaMKII phosphorylates the Thr1603 residue (Thr1604 in rabbit) within the preIQ region in the C-terminal tail of the guinea-pig Cav1.2 channel. Mutation of Thr1603 to Asp (T1603D) slowed the run-down of the channel in inside-out patch mode and abolished the time-dependency of the CaM’s effects to reverse run-down. We also found that CaMKII-mediated phosphorylation of the proximal C-terminal fragment (CT1) increased, while dephosphorylation of CT1 decreased its binding with CaM. These findings suggest that CaMKII regulates the CaM binding to the channel, and thereby maintains basal activity of the Cav1.2 Ca2+ channel.  相似文献   
967.
Repetitive transcranial magnetic stimulation (rTMS) has recently been widely employed for the investigation of brain function and treatment of psychiatric and neurological disorders. Although high and low stimulation frequencies are assumed to activate and deactivate brain function, respectively, the optimal parameters of rTMS for treatment of depression have been determined only on the basis of their clinical efficacy. In this study, we administered a 60-s low-frequency rTMS of three grades low intensities over the right dorsolateral prefrontal cortex (DLPFC) in 10 healthy volunteers, and monitored functional changes of the contralateral DLPFC by near-infrared spectroscopy (NIRS) during and immediately after rTMS. Obtained results demonstrated significant [oxy-Hb] decreases during rTMS, and significant differences in the time courses of [oxy-Hb] changes among three stimulus intensities, that is, [oxy-Hb] decreases were most prominent during the latter half of the stimulation and the first 30s of poststimulation only at 15mm condition (58% intensity). These results suggest that monitoring of brain functional changes due to rTMS using NIRS is useful for elucidating the brain mechanisms underlying the clinical effects of rTMS, and the effects of rTMS over contralateral DLPFC are obtained if the stimulus intensities are more than one-half of the motor thresholds.  相似文献   
968.
In the present study, we investigated subpopulations of natural killer (NK) cells and the expression of stimulatory and inhibitory NK receptors after adult blood and bone marrow transplantation (BBMT) and cord blood transplantation (CBT). There were significant increases in CD16+CD56dim cell proportion and in absolute number in peripheral blood mononuclear cells (PBMC) during a period of 4–9 months after CBT compared with these in normal PBMC, cord blood (CB), and in PBMC after BBMT. Also, increased numbers of CD16+CD56dim NK cells were sustained in some patients until 4 years after CBT. This CD16+CD56dim cell subset after CBT exhibited decreased expression of NKG2A compared with that in CB and increased expression of NKG2C. Purified CD16+CD56dim cells from patients 8–9 months after CBT exhibited significantly higher levels of cytolytic activity against K562 than did purified CD16+CD56bright cells and also whole PBMC. The CD16+CD56dim cell subset with a high level of cytolytic activity significantly increased after CBT, and these cells may be responsible for NK cell–mediated immunity after CBT.  相似文献   
969.
PROBLEM: Oxygen radical formation by neutrophils during pregnancy is not well studied. METHOD OF STUDY: We studied neutrophil-derived superoxide anion (O) and nitric oxide (NO) values in 75 normal pregnant women, 12 postpartum women, and 10 non-pregnant women. O production was measured by the superoxide dismutase-inhibitable reduction of ferricytochrome c. NO production was measured by accumulation of the stable end product nitrite using a modified Griess reaction method. RESULTS: O production of neutrophils stimulated by chemotactic peptide was significantly enhanced in the early second trimester of pregnancy. l-arginine analogue-inhibitable nitrite production was induced in neutrophils from pregnant women, but not from postpartum and non-pregnant subjects. In third-trimester subjects but not non-pregnant subjects, neutrophils pre-treated with l-arginine analogues enhanced O production compared with untreated neutrophils. CONCLUSION: These findings indicate that O and NO production by neutrophils during pregnancy were modulated separately, whereas neutrophil-derived NO might function as a regulator of O.  相似文献   
970.
The purpose of the present study was to identify gene polymorphisms for the reliable assessment of genetic factors for obesity. The study population comprised 3906 unrelated Japanese individuals (2286 men, 1620 women), including 1196 subjects (677 men, 519 women) with obesity (body mass index of > or = 25 kg/m2) and 2710 controls (1609 men, 1101 women). The genotypes for 147 polymorphisms of 124 candidate genes were determined with a method that combines the polymerase chain reaction and sequence-specific oligonucleotide probes with suspension array technology. Multivariable logistic regression analysis with adjustment for age, sex, and the prevalence of smoking revealed that the -30Gright curved arrow A polymorphism of GCK, the -240Aright curved arrow T polymorphism of ACE, and the -482Cright curved arrow T polymorphism of APOC3 were significantly (P < 0.01) associated with the prevalence of obesity, and the -1989Tright curved arrow G polymorphism of ESR1 was almost significantly associated. A stepwise forward selection procedure demonstrated that ACE, GCK, and ESR1 genotypes significantly (P < 0.01) and independently affected the prevalence of obesity. Combined genotype analysis for these three polymorphisms yielded a lowest odds ratio of 0.45 for the combined genotypes of AT or TT for ACE, GG for GCK, and GG for ESR1 in comparison with the combined genotypes of AA for ACE, GG for GCK, and TT or TG for ESR1. Genotypes for ACE, GCK, and ESR1 may prove reliable for the assessment of genetic factors for obesity. Determination of the combined genotypes for these genes may contribute to the personalized prevention of this condition.  相似文献   
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