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31.
Andrew M Passam Alexandros Zafiropoulos Spiros Miyakis Ioannis Zagoreos Nikolaos G Stavrianeas Elias Krambovitis Demetrios A Spandidos 《Journal of clinical virology》2005,34(4):302-309
BACKGROUND: The chemokine receptor polymorphisms CCR5Delta32, CXCL12 3'A, CCR2-64I and CCR5-59029 G/A have been demonstrated to affect HIV-1 infection and progression. OBJECTIVE: We studied the impact of the above polymorphisms on the effectiveness of a 30-month treatment with highly active antiretroviral therapy (HAART) in 149 HIV-1 patients. STUDY DESIGN: We stratified the patients according to CD4 CDC criteria and applied Kaplan-Meier analysis using the following end-point criteria: (a) the time from HAART initiation to undetectable viral load (VL) counts (VL<50 copies/ml), (b) the duration of undetectable VL status and (c) the time required for CD4+ T-cell counts to pass over the 500 cells/ml threshold. RESULTS: Our results in the second group (CD4 201-500) revealed that patients with the CCR2-64I allele achieved undetectable VL counts at 3.5+/-0.48 months as compared to 10.26+/-1.42 months in the control group (p=0.018). The VL remained undetectable for 28+/-2 months, in contrast to 20+/-2 months in the control group (p=0.048). Patients carrying CXCL12 3'A restored the CD4 population faster than the control group (9+/-2 and 14+/-2 months, respectively, p=0.023). The CCR5Delta32 and CCR5-59029 G/A alleles did not appear to affect the parameters studied. CONCLUSIONS: Our results suggest that patients carrying either CCR2-64I or CXCL12 3'A have a more favorable prognosis during HAART treatment. 相似文献
32.
Petter Fagerberg Evangelia Charmandari Christos Diou Rachel Heimeier Youla Karavidopoulou Penio Kassari Evangelia Koukoula Irini Lekka Nicos Maglaveras Christos Maramis Ioannis Pagkalos Vasileios Papapanagiotou Katerina Riviou Ioannis Sarafis Athanasia Tragomalou Ioannis Ioakimidis 《Nutrients》2021,13(3)
Fast self-reported eating rate (SRER) has been associated with increased adiposity in children and adults. No studies have been conducted among high-school students, and SRER has not been validated vs. objective eating rate (OBER) in such populations. The objectives were to investigate (among high-school student populations) the association between OBER and BMI z-scores (BMIz), the validity of SRER vs. OBER, and potential differences in BMIz between SRER categories. Three studies were conducted. Study 1 included 116 Swedish students (mean ± SD age: 16.5 ± 0.8, 59% females) who were eating school lunch. Food intake and meal duration were objectively recorded, and OBER was calculated. Additionally, students provided SRER. Study 2 included students (n = 50, mean ± SD age: 16.7 ± 0.6, 58% females) from Study 1 who ate another objectively recorded school lunch. Study 3 included 1832 high-school students (mean ± SD age: 15.8 ± 0.9, 51% females) from Sweden (n = 748) and Greece (n = 1084) who provided SRER. In Study 1, students with BMIz ≥ 0 had faster OBER vs. students with BMIz < 0 (mean difference: +7.7 g/min or +27%, p = 0.012), while students with fast SRER had higher OBER vs. students with slow SRER (mean difference: +13.7 g/min or +56%, p = 0.001). However, there was “minimal” agreement between SRER and OBER categories (κ = 0.31, p < 0.001). In Study 2, OBER during lunch 1 had a “large” correlation with OBER during lunch 2 (r = 0.75, p < 0.001). In Study 3, fast SRER students had higher BMIz vs. slow SRER students (mean difference: 0.37, p < 0.001). Similar observations were found among both Swedish and Greek students. For the first time in high-school students, we confirm the association between fast eating and increased adiposity. Our validation analysis suggests that SRER could be used as a proxy for OBER in studies with large sample sizes on a group level. With smaller samples, OBER should be used instead. To assess eating rate on an individual level, OBER can be used while SRER should be avoided. 相似文献
33.
Ioannis Gkiatas William Xiang Allina A. Nocon Mark P. Youssef T. David Tarity Peter K. Sculco 《The Journal of arthroplasty》2021,36(8):2907-2912
BackgroundThe incidence of heterotopic ossification (HO) after total knee arthroplasty (TKA) varies and is of unclear clinical significance. This study aimed to identify the incidence of HO in patients undergoing revision TKA for either stiffness or aseptic loosening/instability and determine if the presence of HO is associated with inferior absolute range of motion (ROM) and ROM gains.MethodsEighty-seven patients were prospectively enrolled and separated into 2 cohorts to evaluate ROM after revision TKA (2017-2019). Group 1 (N = 40) patients were revised for stiffness, while group 2 (N = 47) patients were revised for either aseptic loosening or instability. Goniometer-measured ROM values were obtained preoperatively and at 6 weeks, 6 months, and 1 year postoperatively. Statistical analysis included a Fisher’s exact test to assess for an association between preoperative HO and final ROM at 1 year after revision TKA.ResultsHO was identified on preoperative radiographs in 17 patients (20%). There was a significantly higher rate of preoperative HO in patients revised for stiffness compared to patients revised for instability or loosening (30% vs 11%; P = .03). Five cases of HO qualitatively identified as most clinically severe were associated with lower ROM at each time point compared to the remainder of HO cases in this study cohort (P < .02).ConclusionThe presence of HO is greater in patients undergoing revision TKA for stiffness. Additionally, HO severity appears to have a major effect on preoperative and postoperative ROM trajectory. This information should help guide patient expectations and highlight the need for a comprehensive, standardized classification system for HO. 相似文献
34.
35.
Eric N. Windsor Abhinav K. Sharma Ioannis Gkiatas Ameer M. Elbuluk Peter K. Sculco Jonathan M. Vigdorchik 《HSS journal》2021,17(1):51
With the increase in technological advances over the years, telehealth services in orthopedic surgery have gained in popularity, yet adoption among surgeons has been slow. With the onset of the COVID-19 pandemic, however, orthopedic surgery practices nationwide have accelerated adaptation to telemedicine. Telehealth can be effectively applied to total joint arthroplasty, with the ability to perform preoperative consultations, postoperative follow-up, and telerehabilitation in a virtual, remote manner with similar outcomes to in-person visits. New technologies that have emerged, such as virtual goniometers, wearable sensors, and app-based patient questionnaires, have improved clinicians’ ability to conduct telehealth visits. Benefits of using telehealth include high patient satisfaction, cost-savings, increased access to care, and more efficiency. Notably, some challenges still exist, including widespread accessibility and adaptation of new technologies, inability to conduct an in-person orthopedic physical examination, and regulatory barriers, such as insurance reimbursement, increased medicolegal risk, and privacy and confidentiality concerns. Despite these hurdles, telehealth is here to stay and can be successfully incorporated in any total joint arthroplasty practice with the appropriate adjustments. 相似文献
36.
37.
Nikolaos Athanasiou Katerina Baou Eleni Papandreou Georgia Varsou Anastasia Amfilochiou Elisavet Kontou Athanasia Pataka Konstantinos Porpodis Ioanna Tsiouprou Evangelos Kaimakamis Serafeim-Chrysovalantis Kotoulas Evgenia Katsibourlia Christina Alexopoulou Izolde Bouloukaki Meropi Panagiotarakou Aspasia Dermitzaki Nikolaos Charokopos Kyriakh Pagdatoglou Kallirroi Lamprou Sofia Pouriki Foteini Chatzivasiloglou Zoi Nouvaki Alexandra Tsirogianni Ioannis Kalomenidis Paraskevi Katsaounou Emmanouil Vagiakis 《Journal of sleep research》2023,32(1):e13656
Growing evidence suggests that sleep could affect the immunological response after vaccination. The aim of this prospective study was to investigate possible associations between regular sleep disruption and immunity response after vaccination against coronavirus disease 2019 (COVID-19). In total, 592 healthcare workers, with no previous history of COVID-19, from eight major Greek hospitals were enrolled in this study. All subjects underwent two Pfizer–BioNTech messenger ribonucleic acid (mRNA) COVID-19 vaccine BNT162b2 inoculations with an interval of 21 days between the doses. Furthermore, a questionnaire was completed 2 days after each vaccination and clinical characteristics, demographics, sleep duration, and habits were recorded. Blood samples were collected and anti-spike immunoglobulin G antibodies were measured at 20 ± 1 days after the first dose and 21 ± 2 days after the second dose. A total of 544 subjects (30% males), with median (interquartile range [IQR]) age of 46 (38–54) years and body mass index of 24·84 (22.6–28.51) kg/m2 were eligible for the study. The median (IQR) habitual duration of sleep was 6 (6–7) h/night. In all, 283 participants (52%) had a short daytime nap. In 214 (39.3%) participants the Pittsburgh Sleep Quality Index score was >5, with a higher percentage in women (74·3%, p < 0.05). Antibody levels were associated with age (r = −0.178, p < 0.001), poor sleep quality (r = −0.094, p < 0.05), insomnia (r = −0.098, p < 0.05), and nap frequency per week (r = −0.098, p < 0.05), but after adjusting for confounders, only insomnia, gender, and age were independent determinants of antibody levels. It is important to emphasise that insomnia is associated with lower antibody levels against COVID-19 after vaccination. 相似文献
38.
Ioannis P Fouyas Paul A T Kelly Isobel M Ritchie Ian R Whittle 《British journal of pharmacology》1997,121(1):49-56
- Evidence that nitric oxide (NO) bioactivity is altered in chronic hypertension is conflicting, possibly as a result of heterogeneity in both the nature of the dysfunction and in the disease process itself. The brain is particularly vulnerable to the vascular complications of chronic hypertension, and the aim of this study was to assess whether differences in the cerebrovascular responsiveness to the NO synthase (NOS) inhibitors, NG-nitro-L-arginine methyl ester (L-NAME) and 7-nitroindazole (7-NI), and to the NO donor 3-morpholinosydnonimine (SIN-1) might indicate one possible source of these complications.
- Conscious spontaneously hypertensive (SHR) and WKY rats, were treated with L-NAME (30 mg kg−1, i.v.), 7-NI (25 mg kg−1, i.p.), SIN-1 (0.54 or 1.8 mg kg−1 h−1, continuous i.v. infusion) or saline (i.v.), 20 min before the measurement of local cerebral blood flow (LCBF) by the fully quantitative [14C]-iodoantipyrine autoradiographic technique.
- With the exception of mean arterial blood pressure (MABP), there were no significant differences in physiological parameters between SHR and WKY rats within any of the treatment groups, or between treatment groups. L-NAME treatment increased MABP by 27% in WKY and 18% in SHR groups, whilst 7-NI had no significant effect in either group. Following the lower dose of SIN-1 infusion, MABP was decreased to a similar extent in both groups (around −20%). There was no significant difference in MABP between groups following the higher dose of SIN-1, but this represented a decrease of −41% in SHR and −21% in WKY rats.
- With the exception of one brain region (nucleus accumbens), there were no significant differences in basal LCBF between WKY and SHR. L-NAME produced similar decreases in LCBF in both groups, ranging between −10 and −40%. The effect of 7-NI upon LCBF was more pronounced in the SHR (ranging from −34 to −57%) compared with the WKY (ranging from −14 to −43%), and in seven out of the thirteen brain areas examined there were significant differences in LCBF.
- Following the lower dose of SIN-1, in the WKY 8 out of the 13 brain areas examined showed significant increases in blood flow compared to the saline treated animals. In contrast, only 2 brain areas showed significant increases in flow in the SHR. In the rest of the brain areas examined the effects of SIN-1 upon LCBF were less marked than in the WKY.
- Infusion of the higher dose of SIN-1 resulted in further significant increases in LCBF in the WKY group (ranging between +30% and +74% compared to saline-treated animals), but no significant effects upon LCBF were found in the SHR. As a result, there were significant differences in LCBF between SIN-1-treated WKY and SHR in six brain areas. In most brain areas examined, cerebral blood flow in SHR following the higher dose of SIN-1 was less than that measured with the lower dose of SIN-1.
- Despite comparable reductions in MABP (∼20%) in both groups, calculated cerebrovascular resistance (CVR) confirmed that the vasodilator effects of the lower dose of SIN-1 were significantly more pronounced throughout the brain in the WKY (ranging between −3% and −50%; median=−38%) when compared to the SHR (ranging between −10% and −36%; median=−26%). In the animals treated with the higher dose of SIN-1, CVR changes were broadly similar in both groups (median=−45% in WKY and −42% in SHR), but with the reduction in MABP in SHR being twice that found in WKY, this is in keeping with an attenuated blood flow response to SIN-1 in the SHR.
- The results of this study indicate that NO-dependent vasodilator capacity is reduced in the cerebrovasculature of SHR. In addition, the equal responsiveness to a non-specific NOS inhibitor but an enhanced effectiveness of a specific neuronal NO inhibitor upon LCBF in the SHR could be consistent with an upregulation of the neuronal NO system.
39.
Aidonopoulos AP Papavramidis ST Zaraboukas TG Habib HW Pothoulakis IG 《Obesity surgery》1994,4(1):8-12
Morbidly obese patients constitute a high risk group for the development of gallbladder disease. In our series 70 consecutive
patients underwent vertical gastroplasty in an effort to manage morbid obesity. The mean age was 37 years (range 20-60), and
the mean excess body weight was 92 kg (range 52-265). Six patients (8.5%) had undergone cholecystectomy before bariatric surgery
because of symptomatic cholelithiasis. The remaining 64 patients underwent cholecystectomy at the time of vertical gastroplasty.
Ninety-seven percent of the removed gallbladders had gross or histologic abnormalities, including cholelithiasis 18.5% (13
patients), and cholesterolosis 31% (22 patients). Histologically, chronic cholecystitis was present in all patients with cholelithiasis
and cholesterolosis. Chronic cholecystitis alone was found in 27 patients (38.5%) and only two patients (3%) had normal findings.
The mean excess body weight of the patients with cholesterolosis (96 kg) was not significantly greater than that of patients
with cholelithiasis (89 kg) or chronic cholecystitis (88 kg). Our findings suggest that cholecystectomy should be performed
in all morbidly obese patients concomitant with vertical gastroplasty. 相似文献
40.
Background: Predicting successful outcomes after bariatric surgical procedures has been difficult, and the establishment of
specific selection criteria has been a subject of ongoing research. In an effort to choose the most appropriate surgical procedure
for each patient, we have established a specific set of selection criteria for each procedure based on degree of obesity,
preoperative dietary habits, eating behavior, and various metabolic features. Methods: From June 1994 to December 1998, 90
bariatric surgical procedures were performed at the authors' institution by a single surgeon (F.K.) based on specific selection
criteria. Vertical banded gastroplasty (VBG) was performed in 35 patients, standard Roux-en-Y gastric bypass (RYGB) in 38
patients, and distal RYGB in 17 patients. All patients were monitored postoperatively 1, 3, 6, and 12 months and once per
year thereafter, with an additional visit at 18 months in distal RYGB patients. Results: Early postoperative morbidity (<30
days) did not differ significantly between the three groups and averaged 9% of total patients. Long-term postoperative morbidity
(>30 days) included 9 incisional hernias (2 in the VBG group, 5 after RYGB, and 2 in the distal RYGB group). There were 6
cases of staple-line disruption, 4 after VBG and 2 after standard RYGB, 1 of which resulted in stomal ulcer. Early postoperative
mortality was 0%, and long-term mortality was 1.1%, which was due to pulmonary embolism in 1 standard RYGB patient on the
65th postoperative day. Average percentage of excess weight loss (%EWL) was 62% the first year, 61% the second year, and 50%
the third year in VBG patients, and 63.6%, 65%, and 63.3%, respectively, in standard RYGB patients. In distal RYGB patients,
where the patient number was significantly smaller, the %EWL at 1 and 2 years, respectively, was 51% and 53%. The most significant
metabolic/nutritional complication was the appearance of hypoproteinemia (hypoalbuminemia) in 1 distal RYGB patient 20 months
after surgery, which was corrected by total parenteral nutrition and subsequent increase in dietary protein intake. Significant
improvement or resolution of pre-existing comorbid conditions was observed in all patient groups. The postoperative quality
of eating, as evaluated by variety of food intake and frequency of vomiting, was significantly better in RYGB patients. Conclusions:
These results show that selection of the bariatric surgical procedure to be performed in each patient based on specific criteria
leads to acceptable weight loss, improvement in preexisting comorbid conditions, and a high degree of patient satisfaction
in most patients. On the basis of our own observations as well as those of others, our selection criteria have become more
strict over time and our selection of VBG as the operation of choice increasingly infrequent. 相似文献