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501.
502.
Cyproheptadine (Cph) is an antiserotoninergic and antihistaminergic agent with alpha‐blocking activity and central sedative effect. Cph has been found to be effective in stimulating appetite, but to our knowledge, its direct effects on the intestine have not been documented. We aimed to assess the antisecretory effects of Cph in rat proximal colon using Ussing chambers' technique. In basal and serotonin (5‐HT)‐stimulated conditions, Cph induced a dose‐dependent reduction in short‐circuit current (Isc). This effect was different in fed vs. fasted rats (EC50 = 1.9 × 10?5 m and 4.9 × 10?5 m , respectively). As expected, Cph induced a marked dose‐dependent rightward shift of the concentration–response curve to 5‐HT (pA2 = 5.4). The effect of Cph was found to be close to that of antisecretory agents in the following sequence: peptide YY > somatostatin > clonidine > Cph > C7‐sorbin. To our knowledge, this is the first demonstration that Cph has a direct effect on the inhibition of electrogenic ionic secretion in intestinal epithelium in vitro. Our results indicate that Cph can modulate the intestinal transport of electrolytes and provide a new insight into the peripheral effects of this drug, which is frequently prescribed as appetite stimulator in developing countries.  相似文献   
503.
504.
Bleeding disorders are a common cause of menorrhagia in the adolescent age group. We aimed to evaluate the incidence of hemostatic disorders, using clinical and laboratory findings of bleeding disorders in adolescent girls with menorrhagia. A retrospective chart review used to evaluate adolescent girls with menorrhagia who were referred to Yuzuncu Yil University Pediatric Hematology clinic between January 2010 and December 2014. Out of 52 patients referred for investigation, 50 patients were included in the study. The mean age and mean menarche age were 14.8 ± 1.42 (range: 12–17) and 12.47 ± 0.55, respectively. In 42 % (n = 21) of patients, anemia was detected. In 22 % (n = 11) of patients, a bleeding disorder was detected: five cases with von Willebrand disease, two cases with acute immune thrombocytopenic purpura, one case with Bernard-Soulier syndrome, one case with Glanzmann thrombasthenia, one case with aplastic anemia and one case with factor X deficiency. The remaining 39 out of the 50 patients were finally diagnosed with dysfunctional uterine bleeding. When compared the patients with bleeding disorders and without bleeding disorders, bleeding from other sites, including gingival bleeding or epistaxis, low platelet counts and prolonged activated partial thromboplastin time were found statistically more frequent in patients with bleeding disorders (p < 0.05). Menorrhagia in adolescents is frequently associated with underlying bleeding disorders. Adolescents with heavy menstrual bleeding and a history of nose or gingival bleeding should be evaluated for congenital bleeding disorders.  相似文献   
505.
While the high seroprevalence for the rickettsiae that cause spotted fevers and the multiple pathogenic rickettsiae is known, the data on the distribution of rickettsial diseases in Africa are often incomplete. We collected ticks from domestic or wild animals (generally a source of bushmeat) that were in contact with humans in 2 neighboring countries of tropical West Africa, Guinea and Liberia. In total, 382 ticks representing 6 species were collected in Liberia and 655 ticks representing 7 species were collected in Guinea. We found rickettsiae in 9 different species of ticks from both countries. Rickettsia africae was found in 93–100% of Amblyomma variegatum, in 14–93% of Rhipicephalus (B.) geigyi, Rh. (B.) annulatus, and Rh. (B.) decoloratus, and in several Hyalomma marginatum rufipes and Haemaphysalis paraleachi. A genetic variant of R. africae was found in Amblyomma compressum. R. massiliae was found in 10/61 (16%) of Rh. senegalensis ticks and in 2% of Haemaphysalis paraleachi ticks collected from dogs. We identified a new rickettsia in one of 44 (2%) Ixodes muniensis collected from a dog in Liberia. As this rickettsia is not yet isolated, we propose the provisional name “Candidatus Rickettsia liberiensis” (for the West African country where the host tick was collected).  相似文献   
506.

Objective

Surgical use of robots has evolved over the last 10 years. However, the academic experience with robotic lung segmentectomy remains limited. We aimed to analyze our lung segmentectomy experience with robot-assisted thoracoscopic surgery.

Methods

Prospectively recorded clinical data of 21 patients who underwent robotic lung anatomic segmentectomy with robot-assisted thoracoscopic surgery were retrospectively reviewed. All cases were done using the da Vinci System. A three incision portal technique with a 3 cm utility incision in the posterior 10th to 11th intercostal space was performed. Individual dissection, ligation and division of the hilar structures were performed. Systematic mediastinal lymph node dissection or sampling was performed in 15 patients either with primary or secondary metastatic cancers.

Results

Fifteen patients (75%) were operated on for malignant lung diseases. Conversion to open surgery was not necessary. Postoperative complications occurred in four patients. Mean console robotic operating time was 84±26 (range, 40-150) minutes. Mean duration of chest tube drainage and mean postoperative hospital stay were 3±2.1 (range, 1-10) and 4±1.4 (range, 2-7) days respectively. The mean number of mediastinal stations and number of dissected lymph nodes were 4.2 and 14.3 (range, 2-21) from mediastinal and 8.1 (range, 2-19) nodes from hilar and interlobar stations respectively.

Conclusions

Robot-assisted thoracoscopic segmentectomy for malignant and benign lesions appears to be practical, safe, and associated with few complications and short postoperative hospitalization. Lymph node removal also appears oncologically acceptable for early lung cancer patients. Benefits in terms of postoperative pain, respiratory function, and quality of life needs a comparative, prospective series particularly with video-assisted thoracoscopic surgery.  相似文献   
507.
Aim: The mucocutaneous changes observed during vitamin B12 deficiency in children have been published only as case studies and small case series. In this study, we aimed to demonstrate the frequency of mucocutaneous changes (particularly hyperpigmentation) seen during vitamin B12 deficiency and resolving time of these symptoms with vitamin B12 treatment.

Material and methods: This prospective study was conducted at the pediatrics outpatient clinic of Harran and Yuzuncu Yil University Faculty of Medicine, among 57 patients, aged between 6 and 24 months, who were diagnosed with vitamin B12 deficiency following various examinations and tests. A detailed examination was performed in respect to skin and mucosal findings. Patients with vitamin B12 deficiency were administered intramuscular cyanocobalamin. Prospective examination was continued, and resolving time of symptoms after treatment was recorded.

Results: The mean age of the patients enrolled in the study was found to be 12.75?±?4.75. Hyperpigmentation was reported in 49 (85.96%) patients enrolled in the study; atrophic glossitis in 40 (70.17%), brittle and matt hair in 13 (22.80%), skin lesions (particularly diaper dermatitis) in eight (15.78%) and cheilosis in four (7.01%) patients. Three months after the treatment initiation, hyperpigmentation improved in 87.75%, atrophic glossitis in 97.5% and brittle and matt hair in 92.3% of the patients. Five patients (8.77%) with continuing pigmentation by the end of sixth months were considered as nonresponsive to the treatment.

Conclusion: Deficiency of vitamin B12 should be considered in the differential diagnosis of infants who present with skin and mucosal lesions.  相似文献   
508.
Okutani F  Zhang JJ  Yagi F  Kaba H 《Neuroscience》2002,112(4):901-906
On postnatal day 12, young rats show an aversion to an odor to which they had been exposed along with presentations of foot shock on postnatal day 11. The acquisition of this aversive learning involves and requires disinhibition of the mitral/tufted cells induced by centrifugal noradrenergic activation during somatosensory stimulation. This olfactory learning is established only for the odor to which the rat has been exposed during conditioning. Infusion of the GABA(A) receptor antagonist bicuculline at a high dose (2.0 nmol/each olfactory bulb) into the olfactory bulb in the presence of an odor is capable of developing olfactory aversive responses without somatosensory stimulation in young rats. The purpose of this study is to characterize the properties of bicuculline-induced aversive responses. In contrast to the odor specificity of aversive learning produced by odor-shock conditioning, bicuculline-induced aversive responses lack odor specificity. Namely, bicuculline infusion in the presence of a citral odor results, in a dose-dependent manner, in subsequent aversive responses to strange odors (benzaldehyde and vanillin) that have never been presented. Moreover, bicuculline infusion alone is sufficient to produce dose-dependent aversive responses to strange odors (citral, benzaldehyde and geraniol).From these results we suggest that disinhibition of mitral/tufted cells from granule cells by bicuculline infusion makes young rats aversive to strange odors non-specifically, as if the rats had learned the odor aversion as a result of odor exposure paired with foot shock. Different mechanisms of disinhibition of the mitral/tufted cells may underlie both the pharmacological manipulation and noradrenergic activation by somatosensory stimulation.  相似文献   
509.
Time-resolved (TR) techniques provide a means of discriminating photons based on their time-of-flight. Since early arriving photons have a lower probability of probing deeper tissue than photons with long time-of-flight, time-windowing has been suggested as a method for improving depth sensitivity. However, TR measurements also contain instrument contributions (instrument-response-function, IRF), which cause temporal broadening of the measured temporal point-spread function (TPSF) compared to the true distribution of times-of-flight (DTOF). The purpose of this study was to investigate the influence of the IRF on the depth sensitivity of TR measurements. TPSFs were acquired on homogeneous and two-layer tissue-mimicking phantoms with varying optical properties. The measured IRF and TPSFs were deconvolved using a stable algorithm to recover the DTOFs. The microscopic Beer-Lambert law was applied to the TPSFs and DTOFs to obtain depth-resolved absorption changes. In contrast to the DTOF, the latest part of the TPSF was not the most sensitive to absorption changes in the lower layer, which was confirmed by computer simulations. The improved depth sensitivity of the DTOF was illustrated in a pig model of the adult human head. Specifically, it was shown that dynamic absorption changes obtained from the late part of the DTOFs recovered from TPSFs acquired by probes positioned on the scalp were similar to absorption changes measured directly on the brain. These results collectively demonstrate that this method improves the depth sensitivity of TR measurements by removing the effects of the IRF.OCIS codes: (170.3660) Light propagation in tissues, (170.3890) Medical optics instrumentation  相似文献   
510.
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