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121.
Serum uric acid (UA) levels reflect circulating xanthine oxidase activity and oxidative stress production. Hyperuricemia has been identified in patients who have congestive heart failure and is a marker of poor prognosis in such patients. We investigated the relation between serum UA levels and Killip's classification suggestive of the severity of heart failure and whether hyperuricemia influences mortality of patients who have acute myocardial infarction (AMI). Using the Japanese Acute Coronary Syndrome Study database, we evaluated 1,124 consecutive patients who were hospitalized within 48 hours of onset of symptoms of AMI from January to December 2002. There was a close relation between serum UA concentration and Killip's classification. Patients who developed short-term adverse events had high UA concentrations. Serum UA levels, Killip's class, age, and peak creatine phosphokinase level were significant predictors of long-term mortality. The hazard ratio for patients in the highest quartile of UA was 3.7 compared with those in the lowest quartile for death after AMI after adjustment for independent factors that were related to mortality. The combination of the best UA cutoff (447 micromol/L) for predicting survival based on receiver-operating characteristics analysis and Killip's class significantly predicted the prognosis of acute and long-term AMI-related complications. In conclusion, our results suggest that hyperuricemia after AMI is associated with the development of heart failure. Serum UA level is a suitable marker for predicting AMI-related future adverse events, and the combination of Killip's class and serum UA level after AMI is a good predictor of mortality in patients who have AMI.  相似文献   
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OBJECTIVES: We hypothesized that the plasma atrial natriuretic peptide (ANP) level reflects atrial degenerative change and may predict the outcome of the maze procedure. BACKGROUND: Although a larger preoperative left atrial dimension and longer duration of atrial fibrillation (AF) have been reported in patients with persistent AF than in those with sinus rhythm (SR), these individual factors were not enough to predict the outcome of the maze procedure. METHODS: Preoperative plasma ANP levels were measured in consecutive 62 patients who underwent the Kosakai's modified maze procedure. Moreover, we performed histological and molecular biological examinations in the resected left atrial tissues. RESULTS: The preoperative plasma ANP was lower in the AF group (n = 13) than it was in the SR group (n = 49) (p < 0.001). Multiple logistic regression analysis revealed that duration of AF and plasma ANP were independently associated with postoperative cardiac rhythm. Among 41 patients with a higher plasma ANP or shorter duration of AF than the median value, SR was restored in 95% of patients. In contrast, in 21 patients with a lower plasma ANP and a longer duration of AF than the median value, SR was restored only in 48% of patients. Histological examination revealed that the collagen volume in the left atrial tissue was higher in AF than it was in SR and inversely correlated with plasma ANP. In addition, the messenger RNA expressions of ANP, collagen type I and type III were lower in AF than they were in SR. CONCLUSIONS: These results suggest that a combination of plasma ANP and/or duration of AF may predict the success rate for the maze operation. Advanced atrial degenerative change may result in a decrease of atrial ANP secretion.  相似文献   
125.
Acute depressor effect of alcohol in patients with essential hypertension.   总被引:3,自引:0,他引:3  
To investigate the time course of the effects of alcohol on blood pressure, we studied the response of ambulatory blood pressure, neurohumoral variables, and hemodynamics to a single moderate dose of alcohol in hypertensive patients. Sixteen Japanese men (22-70 years old) with essential hypertension who were habitual drinkers were examined under standardized conditions. On the alcohol intake day, they ingested 1 ml/kg ethanol (vodka) at dinner, and on the control day they consumed a nonalcoholic beverage. The order of the two periods was randomized. Mean ambulatory blood pressure was lower in the alcohol intake period than in the control period (125 +/- 3/74 +/- 2 versus 132 +/- 4/78 +/- 2 mm Hg, p less than 0.05), and the significant depressor effect of alcohol lasted for up to 8 hours after drinking. Blood pressure on the next day did not differ with or without alcohol intake. The acute hypotensive effect of alcohol was associated with an increase in heart rate and cardiac output and with a decrease in systemic vascular resistance as determined by echocardiography. Plasma catecholamine levels and renin activity rose significantly at 2 hours after dinner, whereas vasopressin and potassium levels fell on the alcohol day. Blood glucose and serum insulin levels were comparable between the two periods. Three patients with marked alcohol-induced flush had greater hypotensive and tachycardiac responses than those who did not show an alcohol-induced flush. The change in mean blood pressure induced by alcohol was negatively correlated with age, the baseline blood pressure, and the change in plasma norepinephrine. These results indicate that the major effect of acute alcohol intake is to lower blood pressure through systemic vasodilatation in hypertensive subjects. Ambulatory blood pressure monitoring may be useful for assessing blood pressure in habitual drinkers.  相似文献   
126.
Non‐O157 Shiga toxin‐producing Escherichia coli (STEC) strains are increasingly recognized as foodborne pathogens that trigger hemolytic uremic syndrome (HUS). The detection and isolation of these strains is important, but distinguishing their bacteriological profiles is difficult. A 2‐year‐old girl developed HUS with mild renal involvement 22 days after consuming barbecued meat. Clinical and laboratory findings gradually improved without specific treatment. Because neither enterohemorrhagic E. coli (EHEC) nor Shiga toxins were detected in stool cultures in a clinical laboratory and the patient tested negative for circulating antibodies to O157 lipopolysaccharide, the case was initially diagnosed as probable atypical HUS. Subsequent serodiagnostic microagglutination assay and polymerase chain reaction‐based molecular testing, however, indicated the presence of the EHEC O121:H19 strain with stx2. Thus, to correctly diagnose and treat HUS, a system for detecting non‐O157 STEC in a clinical setting is urgently needed.  相似文献   
127.

Purpose

The purpose of this study was to determine the prevalence of lymphoid hyperplasia in the lower gastrointestinal tract and its role in patients undergoing colonoscopic examinations, particularly focusing on any allergic predisposition.

Methods

A database search performed at the Department of Gastroenterology at Onomichi Municipal Hospital identified seven patients with lymphoid hyperplasia in the large intestine (i.e., cecum, colon, and/or rectum). Data regarding the endoscopic, biological, and pathological examinations performed and the allergic histories for each patient were retrospectively reviewed from the clinical records.

Results

Median age of the patients (four males, three females) was 50 years. Lymphoid hyperplasia was seen in the cecum (n?=?5), ascending colon (n?=?2), and transverse colon (n?=?1). Six patients (85.7 %) had one of the allergic airway diseases: allergic rhinoconjunctivitis for pollen (n?=?3), bronchial asthma (n?=?1), infantile asthma (n?=?1), or allergic bronchitis (n?=?1). Drug allergy (n?=?3) and urticaria (n?=?2) were also found. All seven patients had one or more allergic diseases; however, none had a history of food allergy. Blood tests for allergens revealed that six patients (85.7 %) had positive reactions to inherent allergens, whereas only one patient had a positive reaction to food allergens.

Conclusions

Our results indicate that lymphoid hyperplasia in the large intestine may be associated with allergic airway diseases rather than with food allergies; thus, its presence may be useful to detect patients with underlying airway hyperreactivity.
  相似文献   
128.
G protein-coupled inward rectifiers (GIRKs) are activated directly by G protein betagamma subunits, whereas classical inward rectifiers (IRKs) are constitutively active. We found that a glutamate residue of GIRK2 (E315), located on a hydrophobic domain of the C terminus, is crucial for the channel activation. This glutamate (or aspartate) residue is conserved in all members of the Kir family. Substitution of alanine for the glutamate on GIRK1, GIRK2, and IRK2, expressed in HEK293 cells, greatly reduced the whole-cell currents. The whole-cell current of GIRK channels with a constitutively active gate, GIRK2(V188A), [Yi, B. A., Lin, Y. F., Jan, Y. N. & Jan, L. Y. (2001) Neuron 29, 657-667] was also reduced by the same glutamate mutation. Mean open time and conductance of single channels in GIRK2 and IRK2 were not affected by the mutation, indicating that the reduced whole-cell current resulted from a lowered probability of channel activation. The mutated GIRK and IRK showed normal trafficking to the cell membrane. The mutated GIRK2 retained the ability to interact with G protein betagamma subunits, and it showed almost the same inwardly rectifying property as the wild type. The mutated GIRK1 and GIRK2 retained ion selectivity to K(+) ions. This glutamate residue corresponds to one of the residues causing Andersen's syndrome [Plaster, N. M., Tawil, R., Tristani-Firouzi, M., Canun, S., Bendahhou, S., Tsunoda, A., Donaldson, M. R., Iannaccone, S. T., Brunt, E., Barohn, R., et al. (2001) Cell 105, 511-519]. Our interpretation is that this region of the glutamate residue is crucial in relaying the activating message from the ligand sensor region to the gate.  相似文献   
129.
A more durable mechanical valve may be a better choice for the tricuspid position than a bioprosthesis when the patient already has mechanical prosthesis in the left side of the heart. Eleven cases of triple valve replacement (total follow-up period, 49.5 patient years), all with mechanical valves, are reviewed to assess optimal valve selection. Nine patients had undergone a total of 12 previous cardiac surgeries. Three patients died in hospital (27.3%), but there were no late deaths among the survivors. Two cases of valve thrombosis in the tricuspid position occurred (linearized incidence: 4.04%/patient years) and 1 of these required reoperation. Because of this high incidence of valve thrombosis, the bileaflet mechanical valve is not considered to be the best choice. Even if mechanical valves are implanted in the left side of the heart, a bioprosthesis may be a better choice at the tricuspid position.  相似文献   
130.
Along with the increased use of other laparoscopic procedures, laparoscopic inguinal hernia repair has become widely used because of its minimally invasive nature. Here, we report a case of 66‐year‐old man who underwent transabdominal preperitoneal laparoscopic hernioplasty and developed hemorrhagic shock on postoperative day 1. CT showed postoperative venous hemorrhage from the retropubic space. Successful hemostasis of the massive hemorrhage was achieved laparoscopically. The origin of the hemorrhage was assumed to be the corona mortis vein, which was slightly injured during the operation. Despite the rarity of this complication, surgeons must be aware of the need to carefully dissect and fix the mesh in the retropubic space to avoid injuring the corona mortis. Laparoscopic hemostasis may be an effective alternative to the open approach.  相似文献   
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