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81.
In-depth knowledge of common and aberrant pulp morphology is essential for appropriate diagnosis and treatment planning prior to commencing root canal treatment. Radicular morphology of mandibular premolars has been extensively studied. Considerable variation in the number of canals and roots found in these teeth has been reported.AimThe purpose of this study is to investigate the root and root canal morphology of mandibular first premolar among Saudi Arabian subpopulation in Aseer using CBCT.MethodsCone-beam computed tomography images of Mandibular first premolar were taken from 166 patients which were referred to Armed Forces Hospitals Southern Region (AFHSR), Khamis Mushayt, Asir region Saudi Arabia. All the images were assessed by two Evaluators (An Endodontist and a Radiologist). Inter-examiner reliability was determined and was assessed by KAPPA value.ResultsThe mandibular first premolar (n = 216) distributed as 120 teeth in female and 96 teeth in male. Out of the 120 teeth examined in female groups one canal was seen in 95 (79.2%) teeth, two canals in 19 (15.8%) teeth and three canals in 6 (5%) teeth where as in the Male group out of 96 teeth, 52 (54.1%) teeth showed one canal, 32 (33.3%) teeth with two canals whereas 12 (12.5%) teeth showed presence of three canals.Chi-Square test for mandibular first premolars demonstrated the chance of second canal in the mandibular first premolar more in male than female and these differences was statistically significant (P ≤ 0.05).ConclusionEndodontic therapy of mandibular premolars is a challenge for clinician because of their frequent morphological and anatomical abnormalities. Proper knowledge about number of root canals and canal configuration is a key to success in Endodontic. There is a great variability in different population regarding the root canal configuration in mandibular pre-molars. However, most studies state the mandibular first premolar has one root canal. Also, the most prevalent type of root canal found was Type I vertucci.  相似文献   
82.

Objectives:

To evaluate the gender-specific difference in the prevalence of depression and anxiety and the help-seeking behavior among gastroenterology outpatients.

Methods:

A cross-sectional study was carried out in gastroenterology clinics in 4 hospitals in Riyadh, Saudi Arabia between February and September 2013. A self-administrated questionnaire was developed and administered to patients. The Patient Health Questionnaire (PHQ-9) and Generalized Anxiety Disorder (GAD-7) questionnaires were used to identify depression and anxiety.

Results:

A total of 438 patients completed the study questionnaire; 135 (31%) females, and 303 (69%) males. Compared with males, females had more depression symptoms (44% versus 32%, p=0.012), anxiety symptoms (34% versus 24%, p=0.036), anxiety-associated difficulty (65% versus 52%, p=0.012), but similar suicidal thoughts (14% versus 11%, p=0.347). Females had similar gastrointestinal complaints but longer duration of symptoms. In both females and males, the most common first interventions were using medications (63% versus 69%), and undergoing endoscopy (19% versus 15%), while very few patients initially used herbs or Islamic incantation “Roquia” (7% versus 8%). Compared with males, females were more likely to subsequently seek help at private clinics (23% versus 14%, p=0.014), or with a Quran therapist (11% versus 5%, p=0.012).

Conclusion:

There are clear gender-specific differences in depression and anxiety symptoms and associated perceived difficulty, but modest differences in help-seeking behavior. Female patients at the gastroenterology clinic may deserve more psychological attention to diagnose depression and anxiety and to alleviate their impact.Psychiatric disorders including depression and anxiety have been reported more frequently among females than male patients.1,2 Additionally, depression and anxiety in woman may be associated with increased symptom severity, chronic course, and functional impairment compared with men.3,4 Gender-specific differences in psychological, neurochemical, anatomic, hormonal, genetic, and personality factors have been suggested to explain the gender-specific difference in lifetime prevalence of depression and anxiety.2,4 After developing a disease, the patient behavior can be as active as rapidly seeking help from available healthcare services or as passive as dismissing the symptoms.5 Help-seeking behavior can be defined as the behavior of individual patients in response to developing a disease with the aim to relieve or improve the disease experience.5 Several socio-demographic and psychosocial factors have been reported to influence timing, frequency, and type of the help-seeking behavior among patients with different health problems.6,7 It was suggested that women are more likely than men to seek medical help for their medical and mental problems, but less likely to seek medical help for alcohol problems.8,9 A limited number of studies examined the help-seeking behavior among patients with gastrointestinal symptoms, and did not show a gender-specific difference.10,11 In Saudi Arabia, females apparently have a high burden of depression and anxiety.12,13 Local data on help-seeking behavior are limited and old.14 Additionally, there is a lack of data on any the gender-specific differences in help-seeking behavior, and in depression or anxiety, or help-seeking behavior in gastroenterology patients. The objective of the current study was to evaluate the gender-specific difference in the prevalence of depression and anxiety symptoms, and the help-seeking behavior among gastroenterology outpatients in Saudi Arabia.  相似文献   
83.
Herein, a conductivity method was engaged to explore the effects of a fluoroquinolone drug, namely ciprofloxacin hydrochloride (CFH)/CFH + polyols (organic compounds with multiple hydroxyl groups (glucose and fructose)), on the aggregation phenomenon of sodium dodecyl sulfate (SDS) at different temperatures (298.15–318.15 K) while maintaining a gap of 5 K. In this study, the critical micelle concentration (cmc) of the SDS/SDS + CFH mixture in water and polyols media was determined from plots of the specific conductivity versus the concentration of SDS to gain knowledge of the effects of CFH/CFH + polyols on the micelle formation behavior of SDS. The cmc value of the surfactant decreases in the presence of CFH in an aqueous medium; thus, CFH favors the micellization of SDS. The cmc values of SDS and the SDS + CFH mixture were enhanced in polyols media. The cmc values of SDS/SDS + CFH show a U-shaped behavior with temperature. The counterion dissociation (α) of the pure surfactant is higher in the presence of the drug and is further enhanced through an increase in the CFH concentration in water/polyols media. Different thermodynamic parameters, such as the Gibbs free energy of micellization , standard enthalpy , entropy , different transfer energies and enthalpy–entropy compensation parameters of micellization were determined and illustrated in detail to compare these parameters between the pure SDS and SDS + CFH mixture in polyols media. The negative values of for the SDS/SDS + CFH mixture in all cases indicate spontaneous micelle formation. The and values indicate the presence of both hydrophobic and electrostatic interactions amongst the studied components.

A conductivity method was used to see effects of a ciprofloxacin hydrochloride (CFH)/CFH + polyols (organic compounds with multiple hydroxyl groups (glucose and fructose)) on aggregation phenomenon of sodium dodecyl sulfate (SDS) at 298.15–318.15 K.  相似文献   
84.
Nanoparticles of α-molybdenum oxide (α-MoO3) are directly grown on graphene sheets using a surfactant-free facile one step ultrafast in situ microwave irradiation method. The prepared α-MoO3 and α-MoO3/G nanocomposites are analysed by different characterization techniques to study their structural, morphological and optical properties. Transmission electron microscope images reveal the intercalation of three dimensional (3D) α-MoO3 nanoparticles into 2D graphene sheets without any agglomeration. The electrochemical results exhibit improved performance for the α-MoO3/G composite electrode compared to pristine α-MoO3 owing to its structural superiority. The specific capacitance (Cs) values of the α-MoO3/G composite and pristine α-MoO3 are measured to be 483 and 142 F g−1 respectively at a current density of 1 A g−1. The α-MoO3/G composite maintains a very strong cyclic performance after 5000 cycles. The capacitance retention of the composite electrode shows stable behavior without any degradation confirming its suitability as an enduring electrode material for high-performance supercapacitor applications.

Nanoparticles of α-molybdenum oxide (α-MoO3) are directly grown on graphene sheets using a surfactant-free facile one step ultrafast in situ microwave irradiation method.  相似文献   
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87.
The Telecare Medical Information System (TMIS) provides a set of different medical services to the patient and medical practitioner. The patients and medical practitioners can easily connect to the services remotely from their own premises. There are several studies carried out to enhance and authenticate smartcard-based remote user authentication protocols for TMIS system. In this article, we propose a set of enhanced and authentic Three Factor (3FA) remote user authentication protocols utilizing a smartphone capability over a dynamic Cloud Computing (CC) environment. A user can access the TMIS services presented in the form of CC services using his smart device e.g. smartphone. Our framework transforms a smartphone to act as a unique and only identity required to access the TMIS system remotely. Methods, Protocols and Authentication techniques are proposed followed by security analysis and a performance analysis with the two recent authentication protocols proposed for the healthcare TMIS system.  相似文献   
88.
OBJECTIVE: To examine the effects of cadaveric donor age on outcomes following orthotopic liver transplantation OLT. METHODS: Data were collected on all patients who underwent OLT between January 1997 and December 2004 at the Royal Prince Alfred Hospital, Sydney, New South Wales, Australia. During this period, 313 OLTs were performed: 51 patients 16% received older donor livers OD; 60 or more years old, and 262 84% received younger donor livers YD; less than 60 years old. RESULTS: In the study group 313 patients, we found significantly more recipients of OD liver with blood group O: 51% versus 33% p=0.025 and with fulminant hepatic failure: 9.8% versus 5% p=0.018 compared to YD recipients. No difference between OD and YD liver recipients was found in initial poor graft function: 16/51 31% versus 74/262 28%, primary non-functioning: 6.5% versus 6.5%, the overall graft loss: 15/51 29% versus 62/262 24%, post-revascularization liver biopsy steatosis: 14/40 35% versus 82/232 36% or hepatic artery thrombosis: 1/51 2% versus 8/262 3%. There was no difference in graft actuarial survival between OD and YD recipients at 1, 3, and 5 years, 82% versus 87%, 75% versus 81%, and 75% versus 77% p=0.27 log rank or patient actuarial survival, 86% versus 89%, 79% versus 83%, and 79% versus 80% p=0.336 log rank. CONCLUSION: Orthotopic liver transplantation can be achieved with acceptable outcomes using selected livers from older deceased donors.  相似文献   
89.
The aortic root and ascending aorta can be involved in a wide spectrum of diseases; both congenital and acquired. Progressive aortic root or ascending aortic dilatation and aneurysmal formation can lead to serious complications, including aortic valve incompetence, aortic dissection and aortic rupture. Various medical and surgical strategies have been developed over the past few decades to manage and prevent such complications. In this review, congenital conditions of aortic dilatation will be discussed.  相似文献   
90.
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