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91.
Tentorial sinus     
Summary The authors report a case of tentorial sinus draining the telencephalic and diencephalic tributaries of the basal vein. Dorsally the sinus joined the straight sinus and later the confluence of the sinuses. Attention should be paid to this normal variation whenever a transtentorial surgical approach is considered.
Sinus de la tenteAspect radiologique et anatomique, à propos d'un cas
Résumé Les auteurs rapportent un cas de sinus de la tente du cervelet drainant les affluents télencéphaliques et diencéphaliques de la veine basale. En arrière, le sinus rejoint le sinus droit puis le torcular. Une attention particulière pré-opératoire devrait être accordée à la mise en évidence de cette variété lorsqu'une approche transtentorielle est discutée.
  相似文献   
92.
对46例(92侧)12~40周胎儿标本的上颌窦,行冠状切,HE染色,光镜观察:(1)原始上颌窦在胚胎第20~22周由原始筛漏斗底部扩展而成,上颌窦位于钩突和中鼻道外侧壁的外侧,窦腔与眼眶之间的骨板最薄,且骨化较晚.(2)窦口位于上颌窦的顶部(壁),随胎龄增长,”钩突角”变小.向外下的筛漏斗渐近水平位.(3)出生时,上颌窦大小约3.0×5.0×6.5mm.窦内粘膜上皮细胞呈立方形或矮柱状,其纤毛稀疏,,固有膜增厚、疏松,内含极少量血管和腺体.结果表明:出生时,上颌窦虽已出现,但粘膜厚,窦腔小,且与眼眶的毗邻关系密切,上颌窦粘膜的组织结构与鼻腔粘膜的结构有所不同.  相似文献   
93.
Gaps and fragmentation of the superficial lymph node cortex are considered to provide intranodal shunt flow between the afferent and efferent vessels. Using serial sections of 205 nodes obtained from 27 donated cadavers more than 70 years of age, we examined the histological architecture of the abdominal and pelvic nodes in elderly Japanese. Secondary follicles were rare in the specimens. Cortex gaps were, to a greater or lesser degree, found in all nodes. We classified these nodes into three types according to how often the gap occurred. Type 1 nodes, with a relatively complete shield for the afferent lymph, were most frequently found in gastric nodes, whereas type 3 nodes, with numerous gaps, were often observed in the colic, para-aortic and pelvic nodes. The type 3 nodes showed a specific architecture characterized by a fragmented superficial cortex, three-dimensionally assembled cords and a common sinus between them. Primary follicles were located in the assembled cord structures as well as at the superficial cortex. Irrespective of the type, B and T lymphocyte areas were intermingled in the cortex-like areas. The present results reveal region-specific histological heterogeneity in aged human visceral nodes. Due to increased surface areas, the type 3 architecture seemed to accelerate systemic immunity rather than act as a local barrier in the para-aortic and pelvic nodes, which are located centrally along the lymphatic drainage routes. However, thick trabeculae often seemed to develop in the type 3 sinus to decrease nodal function with aging.  相似文献   
94.
Study on the anatomical dimensions of the human sigmoid colon   总被引:4,自引:0,他引:4  
Although the sigmoid colon is commonly afflicted with disease, studies on its anatomical dimensions are scarce. It is suspected that dimensions of the sigmoid colon change with age. This study documents data on the anatomical measurements of the sigmoid colon in 70 Indian subjects (51 live and 19 cadavers). Seven parameters of sigmoid colon anatomy measured included length and width of the sigmoid colon and mesocolon at specific points. Three mesocolic indices (width to length ratios) were calculated. Comparisons of measurements in the live and cadaver subjects and in the two sexes were made. The relationship of change in parameters with age was assessed. Appropriate statistical methods were used and the differences were considered significant at P < or = 0.05. The study showed wide ranging variations in the values of various measured parameters of the sigmoid colon. Seven patterns of the shape of the sigmoid loop were identified. In the commonest pattern the sigmoid mesocolon was vertically longer than wide (dolichomesocolic), the sigmoid loop having its maximum convexity located just a little proximal to the apex. Patterns where the width of the mesocolon was greater than the vertical length (brachymesocolic) were also observed. The gender analysis showed that the sigmoid mesocolon of the female was brachymesocolic (wider than long), whereas that of the male was dolichomesocolic (longer than wide). This might explain the higher incidence of sigmoid volvulus in the male. This study also showed that the measurements of the sigmoid colon and its mesocolon do not change significantly within the age range of 16-60 years in the two sexes. Also noteworthy is the observation that in the cadaver the sigmoid colon shows considerable shrinkage, particularly of its mesocolon; consequently the data from cadaver subjects, though valuable for anthropometric use, have limitations when used for clinical applications.  相似文献   
95.
Summary The present study was performed on axial and coronal CT scans of 100 patients, most of whom were affected by nasal polyposis. Five observers had to analyse the radiograms and answer a questionnaire including the following items: presence of a supraorbital recess; identification of anterior and posterior ethmoidal canals; dehiscences in the lamina papyracea; pneumatized middle turbinate; presence of a spheno-maxillary plate; presence of Haller's cells; presence of Onodi's cells; relationships of the optic canal; relationships of the internal carotid artery; relationships of the maxillary nerve; relationships of the vidian nerve; level difference between the ethmoid roof and nasal vault; depth of the sphenoethmoidal recess. The data obtained were compared with those drawn from anatomical studies. The fair agreement between them proves the value of CT as an alternative method for studying paranasal sinuses anatomy.
Anatomie radiologique des variations du labyrinthe ethmoïdal et du sinus sphénoïdal et leurs conséquences chirurgicales
Résumé Cette étude a été réalisée sur 100 patients dont la plupart présentait une polypose nasale étudiée en coupes T D M axiale et coronale. Cinq lecteurs ont revu les clichés et répondu au questionnaire suivant: présence d'un récessus supra orbitaire; identification des canaux ethmoïdaux antérieur et postérieur; déhiscence de la lame papyracée; pneumatisation du cornet moyen; présence d'un plateau sphéno maxillaire; présence de cellules de Haller; présence de cellules d'Onodi; rapports du canal optique; rapports de l'artère carotide interne; rapports du nerf maxillaire; rapports du nerf vidien; dénivelé entre le toit ethmoïdal et le toit nasal; profondeur du récessus sphéno-ethmoïdal. Les données obtenues ont été comparées avec celles provenant de travaux anatomiques. La concordance acceptable entre les deux démontre la valeur du scanner comme méthode d'étude alternative de l'anatomie des sinus para nasaux.
  相似文献   
96.
视神经管区的临床应用解剖研究   总被引:19,自引:1,他引:19  
李健  廖建春 《解剖学杂志》1994,17(2):98-101
对50个成人尸头和30个干性颅骨标本的视神经管区进行了显微解剖学研究,测量了视神经管的长度、口径及管壁的厚度、观察了视神经管内壁的毗邻结构关系,还测量了一些与视神经管减压术有关的数据。讨论了经鼻外筛、蝶窦视神经管减压时值得注意的若干问题。  相似文献   
97.
目的:探讨心肌梗死(心梗)患者窦性心律震荡检测的临床意义。方法:测定24小时动态心电监测的170例心梗患者和116例正常人室性早搏(室早)后的震荡初始(TO)和震荡斜率(TS)值及平均值,并进行对比分析。结果:心梗患者室早后的TO值明显高于对照组、鸭值明显低于对照组(P〈0.05和P〈0.01),TO和/或TS异常组死亡率明显高于TO和鸭均正常组(P〈0.001)。结论:心梗后患者窦性心律震荡现象减弱或消失时,其猝死的发生率增高,及时检测心梗患者室早后的TO和TS值,对发生猝死的高危患者的检出、危险度分层以及对其进行干预治疗都有重要的临床意义。  相似文献   
98.
We report two cases of acquired toxoplasmic lymphadenitis, one with toxoplasmic cysts and the organisms of Toxoplasma gondii and the other with the organisms only. These cysts and organisms were observed in paraffin-embedded sections, touch smears and ultrathin sections for electron microscopy. Touch smears were especially valuable for the quick and accurate diagnosis of toxoplasmic lymphadenitis. We also studied immature sinus histiocytosis (ISH) in these cases. The predominant cells of ISH were confirmed to be B lymphocytes immunohistochemically, the majority being positive for polyclonal surface IgM. ISH was observed in the perifollicular and paracortical areas surrounding post-capillary venules (PCV), whereas the sinuses were only partially involved.  相似文献   
99.
目的:报道1例偶然发现的右侧永久性三叉动脉形态、特点,并进行文献复习。方法:利用显微解剖对此例永久性三叉动脉的起源、走行、分支、分布、与后循环连接关系、以及相关动脉解剖特点等进行了研究。结果:此例永久性三叉动脉与脑膜垂体干共干起源于颈内动脉海绵窦段,于展神经外侧进入后颅窝,分支与基底动脉和小脑上动脉吻合,其终末支之一延续为同侧的小脑下后动脉,此动脉与三叉神经关系密切,分支分布于脑干和小脑。结论:永久性三叉动脉与后循环关系复杂,广泛参与正常脑组织供血。  相似文献   
100.
The urethral duct and vagina are formed from the urogenital sinus (UGS) during the early neonatal period in mice. Neonatal estrogen exposure results in hypospadias, or the malpositioning of vaginal and urethral openings, with wide cleft clitoris. We sought to characterize diethylstilbestrol (DES) influence on UGS morphogenesis and hypospadias formation. Newborn (day 0) and 1–4‐day‐old female mice (ICR/Jcl) were given (s.c.) oil or 3.0 μg DES. Animals were killed 24 hr later; then hypospadias formation and epithelial apoptosis and proliferation within the developing UGS were assessed. DES did not alter normal UGS morphogenesis by day 1, in comparison with controls. However, hypospadias formation was observed in DES‐treated mice by day 3. In these mice, the distal dorsal urethral duct appeared to fuse with and open into the lower vaginal solid cord region. Further, DES treatment produced a gradual significant increase in dorsal urethral epithelial apoptosis (P < 0.05) just prior to and during fusion and hypospadias formation. DES‐induced urethral epithelial and sinus cord proliferation appeared significantly increased (P < 0.05) and unchanged, respectively, just prior to fusion. By day 5, DES‐treated mice exhibited wide cleft clitoris. In addition, if DES was given on day 3 or 5, a gradual, distinct caudal shift in the vaginal‐urethral junction was observed compared to mice treated on days 0–2. Although hypospadias was not induced when neonates were given DES on day 7, these mice continued to display early vaginal opening. Dose‐response analysis indicated that 0.03 μg DES for 5 days is the lowest known critical dose for hypospadias induction. We have shown for the first time that DES‐induced hypospadias onset may primarily be the result of changes in developing dorsal urethral epithelial cell apoptotic and proliferative activity, and that the location of DES‐induced hypospadias formation is dependent on age at time of exposure. Anat Rec 266:43–50, 2002. © 2002 Wiley‐Liss, Inc.  相似文献   
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