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101.
We report our experience with 345 premature infants weighing less than 1,500 g admitted to the neonatal intensive care unit during 1990–1993. The improved survival of the very-low-birth-weight patients was related mainly to the routine use of surfactant in the treatment of respiratory distress. In addition, as a result of several preventive precautions, early diagnosis, and appropriate antimicrobial therapy, a decrease in neonatal sepsis was observed. The decrease in the ratio between the number of septic episodes to the number of septic patients is another indication of the efficacy of our current preventive and therapeutic protocols. Correspondence to: S. Katz  相似文献   
102.
Concern over myocardial damage from simultaneous arterial (antegrade) and coronary sinus (retrograde) perfusion has led to alternating between these delivery routes to maximize their individual benefits. Based upon predominant retrograde drainage via Thebesian veins, this study: (1) confirms experimentally the safety of simultaneous arterial and coronary sinus perfusion; and (2) reports initial clinical application of this combined strategy in 155 consecutive patients. Experimental: Five mini-pigs (25 to 30 kg) underwent 1 hour of aortic clamping with simultaneous aortic and coronary sinus perfusion at 200 mUmin with normal blood (37°C) before and after 30 minutes of perfusion with either warm (37°C) or cold (4°C) blood cardioplegia. Coronary sinus pressure was always less than 30 mmHg. There was no right or left ventricular edema, lactate production, or lipid peroxidation as transmyocardial and myocardial conjugated dienes were unaltered, and postbypass recovered left ventricular end-systolic elastance (conductance catheter) and preload recruitable stroke work Index 101%± 3% and 109%± 90%, respectively. Clinical: Simultaneous arteriaVcoronary sinus perfusion was used in 155 consecutive high risk patients (New York Heart Association Class III to IV) undergoing isolated coronary artery bypass grafting (CABG) (n = 109) and CABG + valve replacementlrepair or aneurysm (n = 46). Included were 16 patients in cardiogenic shock and 24 undergoing reoperation. Mean aortic clamping time averaged 90 ± 4 minutes (range 30 to 207), with 3.5 ± 0.1 grafts per patient; all anastomoses were performed with the aorta clamped. Cold intermittent blood cardioplegia was used for distal anastomoses and valve implantationhepair in 123 patients, and warm continuous blood cardioplegia was used in 32 patients. Following a warm cardioplegic reperfusate, all patients received warm non-cardioplegic blood perfusion simultaneously via grafts and coronary sinus. Coronary sinus pressure was always less than 40 mmHg. Of 18 patients requiring postoperative mechanical circulatory support (IABP), 16 had IABP placed preoperatively for cardiogenic shock. There were three postoperative myocardial infarctions (2%), and six patients died (3.9% mortality). Conclusion: These experimental and clinical findings overcome perceived concerns about myocardial damage from simultaneous arterial and coronary sinus perfusion, and suggest this approach may add to the armamentarium of cardioprotective strategies. (J Card Surg 1994;9:15–25)  相似文献   
103.
Oculopharyngeal muscular dystrophy (OPMD), a late onset autosomal dominant myopathy, is common among the French-Canadians and the Jews from Bukhara (Uzbekistan); most clinical histologic and genetic data published until now, as well as the recently suggested diagnostic criteria, are based on studies among the former. We studied 79 patients with OPMD belonging to the newly described Jewish-Bukhara cluster. The disease began between the ages of 21 and 78 yr (median 53 yr). In 11 patients (15%) it began before the age of 40. Ptosis was the first symptom in 59 patients and dysphagia in the remaining 20. Eight patients (10%) were monosymptomatic (ptosis) after more than 7 yr from the start of the disease; however, other family members had additional signs/symptoms. The patients belong to 29 families; in 26 age-dependent autosomal dominant inheritance could be documented. Among them there is certain evidence for genetic anticipation. This clinical study is the largest published concerning patients other than French-Canadians.  相似文献   
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This study was conducted to determine: 1) If healthy subjects can be conditioned to tolerate clinically useful electrically induced muscle contraction; and 2) If there is a gender difference in response to such conditioning. Healthy volunteers (10 males, 11 females, mean age of 27.6 ± 5.8 yrs) were tested during each of 6 testing sessions. Maximal voluntary isometric contractions (MVIC) of the right quadriceps femoris (RQF) recorded by a computerized dynamometer. Electrical stimulation delivered through two surface electrodes and stimulation amplitude increased until the subject indicated to stop. After a 1 min rest the amplitude increased again to the same phase charge level, and the electrically induced contraction (EIC) was recorded by the dynamometer. Measurements of stimulation amplitude were repeated in each of 10 stimulation bouts per session. Measurements of EIC were repeated in session six. Statistical analyses included Multivariate ANOVAs, and Newman-Kuel’s post-hoc tests (p < 0.01). Mean values of phase charge increased from session 1 to 6 for all subjects. Males tolerated significantly higher phase charge. The mean %MVIC torque generated by female subjects was initially only 11.2 ± 21.6% but reached 42.9 ± 25.4% at the end of the 6th session. Males’ %MVIC torque values were significantly higher reaching 49.0 ± 41.6% and 73.5 ± 18.7% in the first and last trials respectively. Using the criterion that electrically induced contractions must be at least 25% of MVIC to be considered clinically useful, 36% of females were below this threshold at the end of the last session. In contrast, all males exceeded the 25% MVIC threshold at the end of the study. Most healthy subjects can be conditioned to electrical stimulation of the quadriceps, but depending on the criteria of therapeutic value and gender, some males and even more females may not reach the desired stimulation goal in 6 sessions. Females may require more conditioning sessions to reach contraction levels of therapeutic benefits. The reason(s) for the confounding factor of gender remains unknown.

Key Points

  • Neuromuscular electrical stimulation (NMES) can strengthen skeletal muscles
  • Tolerance to NMES improves within 6 sessions
  • Conditioning is a key to eliciting stronger contraction and to increasing the number of subjects that can benefit from NMES
  • Healthy males can tolerate higher stimulusintensity and higher electrically induced quadriceps femoris contraction.
Key Words: Neuromuscular electrical stimulation, tolerance, conditioning, gender  相似文献   
107.
Ultrasonographic resolution of nephrocalcinosis (NC) has been reported in children with furosemide-induced NC, but not in other entities. We report the cases of four children with metabolic bone disease, two with hypophosphatasia and two with X-linked hypophosphatemic rickets, in whom we observed resolution of renal calcifications. At the time of ultrasonographic resolution of NC, 3 of the patients were on anticalciuric diuretics, and all 4 had normal urinalysis, serum creatinine and electrolyte profiles, as well as estimated creatinine clearance. In 3 of the children, evidence of mild tubular dysfunction was found. It thus seems that in some children with bone and mineral disorders who develop NC, ultrasonographic resolution of the renal calcifications can be seen; however, mild tubular dysfunction may remain and require follow-up. Further studies are suggested to explore the possible role of anticalciuric diuretics in promoting the resolution of NC.  相似文献   
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109.
BACKGROUND AND AIM OF THE STUDY: Papillary fibroelastoma (PFE) is a rare and histologically benign tumor, but it may have malignant propensity for life-threatening complications. Herein are described four cases of PFE which reflect the clinical diversity of this lesion. The diagnostic and surgical approach utilized is also briefly reviewed. METHODS: The files of four patients with cardiac valvular PFE treated at the authors' center between January 2002 and November 2003 were reviewed. The diagnosis was strongly suggested by echocardiography. Tumors were noted in aortic (n = 2), mitral (n = 1) and tricuspid (n = 1) sites. Indications for surgery were myocardial infarction (both aortic tumors), previous stroke (mitral tumor), and preventive (tricuspid tumor). RESULTS: Surgical excision with a conservative, valve-sparing approach was performed in all cases. For the first aortic tumor, the aortic valve was reconstructed with a patch of autologous pericardium. None of the patients had evidence of valvular regurgitation after excision on intraoperative transesophageal echocardiography, and all had an uneventful recovery. There were no cases of recurrence or regurgitation on follow up echocardiography. CONCLUSION: PFE is an uncommon but increasingly recognized cause of embolic phenomena. Prompt identification allows for surgical excision, which seems to be curative, safe and well-tolerated. A conservative valve-sparing approach is recommended because of the absence of recurrence after total excision.  相似文献   
110.
BACKGROUND: Aspirin is an effective and generally accepted treatment drug during the acute stage of ischemic brain infarction. The association between the pretreatment aspirin dosage and fatal outcome among these treated patient groups has not been analyzed previously. OBJECTIVE: The aim of the study was to evaluate 14- and 30-day poststroke survival in patients treated with 325 mg immediately on admission to the hospital for prestroke antiaggregation/anticoagulation treatment. METHODS: This prospective study was conducted in a government tertiary care facility. The medical records of all 1245 patients admitted to the hospital for stroke from 1997 to 2002 were reviewed. The association between demographic parameters, stroke risk factors, stroke subtype, prestroke antiaggregation/anticoagulation treatment, and risk of fatal poststroke outcome, 14 days and 30 days after the event, was analyzed using Cox survival analyses. RESULTS: During the 14-day poststroke period, 320 patients (25%) died. By day 30 poststroke, 386 patients (31%) had died. Older age, female gender, chronic heart disease, and cardiac arrhythmias were associated with increased risk of increased fatal outcome. Mortality was higher in patients with stroke caused by cardioembolism (P < 0.0001) and was significantly lower in patients with small-vessel occlusion (P < 0.0001). Prestroke medium-dose aspirin treatment was associated with a relative reduction in 30-day poststroke period mortality (P < 0.0001). Conversely, prestroke low-dose aspirin treatment was associated with increased mortality (P < 0.0001). CONCLUSION: Prestroke medium-dose aspirin treatment was associated with reduced 30-day poststroke mortality, whereas low-dose prestroke aspirin therapy was associated with increased 30-day poststroke mortality.  相似文献   
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