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41.
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Journal of Neurology - Nusinersen recently became available as the first treatment for Spinal Muscular Atrophy (SMA) and data on its effectiveness and safety in adult SMA patients are still scarce....  相似文献   
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Cutaneous leishmaniasis (CL) is diverse in its clinical presentation but usually demonstrates an erythematous, infiltrated, ulcerated, and crusted papule or nodule in exposed areas of the body. Rare clinical features have been reported including lymphatic dissemination, usually with subcutaneous nodules along lymphatic channels. Herein, we present six patients suffering from Old World CL with lymphatic dissemination characterized by sporotrichoid subcutaneous nodules along the lymphatic channels draining the primary lesion. Patients'' history, clinical and laboratory findings were collected and summarized. Lymphatic dissemination of CL in our patients manifested as subcutaneous nodules without epidermal involvement within the axis of lymphatic drainage toward the regional lymph node, at times accompanied by regional lymphadenopathy. In all patients, the lymphatic dissemination was not present at initial diagnosis of CL, appearing only after local (topical or intralesional) treatment was initiated. In three patients, the subcutaneous nodules resolved without systemic treatment. Lymphatic dissemination of Old World CL is not uncommon and may possibly be triggered by local treatment. It should be recognized by dermatologists, especially those working in endemic areas. Systemic treatment may be not necessary since spontaneous resolution may occur.Old World cutaneous leishmaniasis (CL) is diverse in its clinical presentation and outcome. The disease spectrum is governed by an interplay between the parasite and the immuno-inflammatory response of the host. The typical clinical presentation of CL is an erythematous, infiltrated, ulcerated, and crusted papule or nodule on any region of the body, with frequent involvement of exposed areas, especially the face and limbs. Lesions heal slowly over a period of months.1 Although CL often resolves spontaneously, it can result in severe disfiguration. Treatment is usually initiated to hasten healing and prevent scarring.2Old World CL is endemic in Israel and was attributed in the past almost exclusively to Leishmania (Leishmania) major, confined to rural areas of the Negev Desert in southern Israel. Over the last decade, CL due to Leishmania tropica has been increasingly reported in the Judean Desert in central Israel, as well as in northern Israel. Leishmania tropica is often more resistant to treatment and heals more slowly than L. major infections.3Lymphatic dissemination of CL is uncommon but has been reported, usually with dermal or subcutaneous nodules along lymphatic vessels draining the region of the primary lesion.47 Herein, we present six cases of CL with subcutaneous sporotrichoid dissemination after local treatment of the primary lesion, probably caused by lymphatic spread of the parasites. The sporotrichoid dissemination was characterized by deep subcutaneous nodules without any sign of epidermal involvement.The demographic, clinical, and laboratory data of the patients are summarized in 8 performed on tissue obtained from primary lesions (patients 4 and 5) or from subcutaneous nodules (patient 6) confirmed L. tropica infection. Regional lymphadenopathy was noted in two patients (patients 2 and 3). In patients 3 and 6, a biopsy from the subcutaneous nodules established the presence of a deep granulomatous process with Leishmania bodies. After the occurrence of subcutaneous nodules, three patients were treated with intravenous sodium stibogluconate (patient 1, 3, and 4), or with sodium stibogluconate injected directly into the primary cutaneous lesion alone (patient 6) or into both the cutaneous lesion and the subcutaneous nodule (patient 5). The patients experienced total resolution of the primary lesions, the subcutaneous nodules, as well as regional lymphadenopathy. On the parents'' request, intralesional injections of pentostam were terminated after a single treatment in patient 2. The primary lesion eventually healed with a scar and the subcutaneous nodules spontaneously regressed within a few weeks.

Table 1

Demographic, clinical, and laboratory findings
CasesSexAge (years)Geographic regionPresenting symptomsInitial treatment before appearance of subcutaneous nodulesMorphology and location of subcutaneous nodulesRegional lymphadenopathyInvestigationsTreatment with intravenous sodium stibogluconateResponse to treatment
1M16Negev Desert8-month history of an infiltrated and ulcerated erythematous plaque on right forearmParomomycin ointmentSubcutaneous painless cord extending proximally in a linear pattern from the right antecubital fossa toward the axilla (Figure 1A, ,BB)NoSmear: positive for amastigotesYesFlattening of the indurated plaque and disappearance of the subcutaneous cord
Doppler ultrasound: infiltration of lymphatic vessels
2M1.8Negev Desert6-month history of an ulcerated erythematous plaque on the right lower foreheadParomomycin ointment and intralesional sodium stibogluconateTwo 5-mm soft and mobile subcutaneous nodules on the right cheek and right upper eyelid with overlying faint pink discoloration (Figure 1C and andC),C), appeared a few weeks after the treatment with intralesional sodium stibogluconateYes (cervical)Smear: positive for amastigotesNoSubcutaneous nodules spontaneously regressed and the ulcerated plaque healed leaving a scar
Ultrasound: nondiagnostic
3F16Judean Desert1-year history of two ulcerated erythematous plaques on right and left forearmsParomomycin ointment and four treatment with intralesional sodium stibogluconate once weeklyNumerous 2-mm subcutaneous nodules above the primary lesions up to the armpit in both upper extremitiesYes (axillary)Smear: positive for amastigotesYesFlattening of the primary lesions and disappearance of the subcutaneous nodules
Ultrasound: nondiagnostic.
Biopsy (from a subcutaneous nodule on the left arm):normal epidermis and dermis, an epithelioid granuloma with plasma cells and abundance of Leishmania bodies was noted in the subcutaneous fat (Figure 2
4M9Judean Desert10-month history of infiltrated erythematous, ulcerated plaques on the right cheek, right upper lip, angle of mouth, and left forearmTwo intralesional treatments with sodium stibogluconateSubcutaneous cord extending from the right angle of the mouth to the right aspect of the jaw (Figure 3A)NoSmear: positive for amastigotesYesResolution of the subcutaneous cord and flattening of the plaques on face and forearm
ITS1-PCR: tissue from a primary lesion was positive for Leishmania tropica
5F7Judean Desert2 months history of erosive erythematous plaques at the tip of the nose, upper lip and five papules on right armThree intralesional treatments with sodium stibogluconateTwo subcutaneous nodules, without overlying erythema, proximal to the nose lesionNoSmear: positive for amastigotesNoContinued treatment with intralesional sodium stibogluconate with resolution of the lesions, as well as the subcutaneous nodules
ITS1-PCR: tissue from a primary lesion was positive for L. tropica
6M17Judean Desert3 months history of an ulcerated plaque on the middle phalanx of the fourth finger and an erythematous erosive plaque on right upper armOne intralesional treatment with sodium stibogluconateTwo subcutaneous nodules on the dorsal aspect of the right hand, proximal to the lesion on fourth finger (Figure 3C, ,DD)NoBiopsy (from a subcutaneous nodule): profound granulomatous process in the deep dermis with necrosis in the form of palisading granulomas. Suspicious Leishmania bodies were noticed within necrotic areasNoContinued treatment with intralesional sodium stibogluconate with resolution of the lesions, as well as the subcutaneous nodules
ITS1-PCR: tissue from a subcutaneous nodule was positive for L. tropica
Open in a separate windowF = female; M = male; ITS1-PCR = internal transcribed spacer 1 polymerase chain reaction.Open in a separate windowFigure 1.(A) A 5-cm infiltrated and ulcerated erythematous plaque over the right forearm in patient 1. (B) Lymphatic dissemination without epidermal involvement in patient 1. (C) A 3-cm ulcerated erythematous plaque on the right lower forehead and two 5-mm soft and mobile subcutaneous nodules on the right cheek and right upper eyelid with overlying faint pink discoloration in patient 2.Open in a separate windowFigure 2.Histopathological findings from a subcutaneous nodule on the left forearm in patient 3: inflammatory infiltrate composed of lymphocytes, histiocytes, and abundant macrophages; round or oval basophilic structures can be seen consistent with Leishmania amastigotes (hematoxylin and eosin, original magnification ×600).Open in a separate windowFigure 3.(A) Infiltrated erythematous, ulcerated plaques on the right cheek, right upper lip, and angle of mouth with a painless subcutaneous cord extending from the right angle of the mouth to the right chin in patient 4. (B) A 2-cm erythematous ulcer on nose tip with subcutaneous nodes extending proximally in patient 5. (C) A 1.5-cm ulcer on the dorsal aspect of the middle phalanx of the fourth finger in patient 6. (D) Subcutaneous nodules on the dorsum of the right hand, proximal to the finger lesion in patient 6.Sporotrichoid dissemination is characterized by the development of secondary lesions, often associated with lymphangitis that progresses along dermal and subcutaneous lymphatics.The exact prevalence of Old World sporotrichoid CL is unknown but ranges between 10% and 19% of affected individuals in previous reports.6,7 The majority of reported sporotrichoid CL cases were shown to be caused by L. major,4,7 although L. tropica has also been implicated. The prevalence of this phenomenon may be species dependent but there are no data comparing rates of sporotrichoid CL among various species. Akilov and others9 in their classification of Old World CL also described this pattern of local spread of CL. They regard the sporotrichoid subcutaneous nodules as a form of lymphatic dissemination of the parasite and describe three clinical patterns: 1) subcutaneous nodules in proximity to the primary lesion, 2) dilated palpable lymphatic vessels in the form of a “beaded cord,” and 3) regional lymphadenitis,9 all seen in our case series.Lymphatic dissemination in our patients manifested in the form of subcutaneous nodules without the typical surface changes noted in primary CL lesions (scaling, crusts, erosions, or ulcers). This was confirmed by the biopsy specimens taken from patients 3 and 6 showing the lack of epidermal and superficial dermal involvement. The nodules were either located within the axis of lymphatic drainage toward the regional lymph node or were accompanied by regional lymphadenopathy. The presence of numerous Leishmania bodies in biopsy specimens of patients 3 and 6 supports the notion that the subcutaneous nodules represent metastases of the parasitic infection.In all our patients, the lymphatic dissemination was absent at initial diagnosis of CL and appeared only after local treatment was initiated. In the 261 patients who attended our Leishmania clinic over the last 2 years, sporotrichoid dissemination was observed only in the six herein reported cases (2.3%), suggesting that local treatment may trigger for this phenomenon, although a proof of cause and effect is currently lacking. Previous reports in the literature also suggest that lymphatic dissemination may be evoked by antiparasitic therapy, especially the use of local irritants and local injections.7,9 It has been shown that intralesional sodium stibogluconate induces an inflammatory response at the site of injection as well as tissue damage,10 which may activate lymphatic drainage and result in parasitic dissemination. Therefore, we hypothesize that the tissue damage caused by local treatment triggers the spread of the parasites into the subcutis and lymphatic vessels. Large prospective studies in endemic areas, where ITS1-PCR can be performed for parasite speciation using a large prospective randomized controlled trial, are needed to prove the causative relationship raised here between local treatment and lymphatic spread of CL.Pentavalent antimonials such as sodium stibogluconate and meglumine antimoniate either systemically or intralesionally have been used to treat sporotrichoid CL.4,7 In three patients (patients 2, 5, and 6), we observed disappearance of the subcutaneous nodules following the resolution of the primary lesions, without initiating systemic treatment. Therefore, we suggest that initiation of systemic treatment in cases of lymphatic dissemination of Old World CL should be guided by the response of the primary lesion to the local treatment. Although no information is available, this may not be true for New World CL, where concern for mucosal disease exists.Lymphatic dissemination of Old World CL is uncommon. This pattern of lymphatic and subcutaneous spread of CL, possibly triggered by local treatment, should be recognized by dermatologists, especially those working in endemic areas. Awareness to this phenomenon will prevent unnecessary workup to investigate the nature of the subcutaneous lesions.  相似文献   
46.

Purpose

To describe the applied anatomy of a minimally invasive muscle-splitting approach used to reach the posterior aspect of the C1–C2 complex.

Summary of background data

Atlantoaxial fusion using a midline posterior approach and polyaxial screw and rod system is widely used. Although minimally invasive variations of this technique have been recently reported, the complex applied anatomy of these approaches has not been described. The C1–C2 complex represents an unique challenge because of its bony and vascular anatomy. In this study, the applied anatomy and feasibility of this technique are examined on cadavers.

Methods

The microsurgical anatomy of the upper cervical spine is examined on a formalin-fixed and on a fresh cadaver. The muscle-splitting approach is performed on 12 fresh cadavers using this technique.

Results

The minimally invasive muscle-splitting approach is described in detail. Relevant anatomy and bony landmarks that aid screw placement in C1 and C2 could be well visualized. Using this approach, we were able to reach the lateral mass of the atlas and the inferior articular process and pars interarticularis of the axis in all of the nine cadavers. We placed mini polyaxial screws in C1 lateral mass and C2 pars interarticularis in four cadavers according to the technique described by Harms and Melcher.

Conclusions

Using this approach, it was possible to reach the posterior aspect of C1 and C2; the relevant anatomy needed to perform a C1–C2 fusion could be well visualized.  相似文献   
47.
A poor nutritional state and a caloric deficit associate with increased morbidity and mortality, but a recent multicenter, randomized controlled trial found that early parenteral nutrition to supplement insufficient enteral nutrition increases morbidity in the intensive care unit, including prolonging the duration of renal replacement therapy, compared with withholding parenteral nutrition for 1 week. Whether early versus late parenteral nutrition impacts the incidence and recovery of AKI is unknown. Here, we report a prespecified analysis from this trial, the Early Parenteral Nutrition Completing Enteral Nutrition in Adult Critically Ill Patients (EPaNIC) study. The timing of parenteral nutrition did not affect the incidence of AKI, but early initiation seemed to slow renal recovery in patients with stage 2 AKI. Early parenteral nutrition did not affect the time course of creatinine and creatinine clearance but did increase plasma urea, urea/creatinine ratio, and nitrogen excretion beginning on the first day of amino acid infusion. In the group that received late parenteral nutrition, infusing amino acids after the first week also increased ureagenesis. During the first 2 weeks, ureagenesis resulted in net waste of 63% of the extra nitrogen intake from early parenteral nutrition. In conclusion, early parenteral nutrition does not seem to impact AKI incidence, although it may delay recovery in patients with stage 2 AKI. Substantial catabolism of the extra amino acids, which leads to higher levels of plasma urea, might explain the prolonged duration of renal replacement therapy observed with early parenteral nutrition.The development of AKI is a frequent and devastating condition in patients admitted to the intensive care unit (ICU). Short-term mortality is high and increases with worsening AKI stages.1 In AKI survivors, renal recovery is often incomplete, progression to ESRD may be accelerated, and longer-term mortality rates are increased compared with non-AKI patients.2,3 Patient management consists of maximal prevention of additional renal damage by hemodynamic stabilization and prevention of (iatrogenic) nephrotoxicity. A curative strategy for established AKI is currently unavailable.4Observational studies, finding associations between a poor nutritional state and increased morbidity and mortality of AKI patients5 and between accumulation of a caloric deficit and poor renal and survival outcome of ICU patients,6,7 have led to the hypothesis that feeding could ameliorate kidney injury and improve survival of ICU patients. However, nutrition, especially parenteral nutrition (PN), also has potential complications.811 Because of the lack of adequately designed studies, nutritional guidelines are largely based on expert opinion.1214 These opinions invariably recommend the early initiation of enteral feeding but substantially differ in their recommendation on when to start supplemental PN.The Early Parenteral Nutrition Completing Enteral Nutrition in Adult Critically Ill Patients (EPaNIC) study was the first large, multicenter, randomized controlled trial (RCT) addressing this important question. The study showed that early initiation of PN increased dependency on intensive care compared with withholding supplemental PN for 1 week (hereafter labeled early PN and late PN, respectively).15 Indeed, early PN prolonged the ICU and hospital length of stay (LOS), increased the incidence of new infections, and prolonged the need for mechanical ventilation. Renal harm was suggested by a clear prolongation of the duration of renal replacement therapy (RRT) in ICU and a trend for more AKI (defined as a doubling or more of ICU admission plasma creatinine). However, the number of patients requiring RRT was unaltered, and recovery to premorbid kidney function was not investigated.It was preplanned to study the detailed impact of early versus late PN on the incidence and recovery of AKI and the time course of blood/urine markers of renal function during ICU stay.16 A priori, we hypothesized that early PN would attenuate kidney injury. However, the original study findings suggested that AKI incidence and renal recovery could be aggravated by increased macronutrient provision in the acute phase of critical illness.  相似文献   
48.
The aim of this study was to compare the safety, morphological outcome, and degree of parental satisfaction of the new spring-mediated cranioplasty with those of the modified pi-plasty in the management of sagittal synostosis. Ten patients with non-syndromic sagittal synostosis treated with the spring-mediated cranioplasty were followed prospectively. A control group of 10 sex-matched patients operated on with the modified pi-plasty procedure was chosen. Cephalometric radiographs were obtained preoperatively and postoperatively at 1 year of age. Cephalic index, axial width ratio, length ratio, width ratio and height ratio were used as objective measures of outcome. Parents were sent a questionnaire to obtain a subjective aesthetic assessment of outcome. Significantly less blood replacement was required (p?=?0.003), and shorter duration of postoperative anaesthesia (p?=?0.030) and postoperative hospital stay (p?=?0.013) were found in the spring-mediated cranioplasty group. There were no complications or deaths in either group. Also significant was the inter-group difference in the postoperative change in the height ratio (p?=?0.030), the most change being seen in the spring group. The change in the subjective parental aesthetic evaluation of skull shape was significant in both groups. In conclusion, the spring-mediated procedure was morphologically more effective than the modified pi-plasty procedure in the management of sagittal synostosis with the additional benefits of less blood transfusion needed and shorter duration of hospital stay.  相似文献   
49.
Abstract

In order to evaluate the role of a hemorrhage versus that of a transient increase in intracranial pressure in subarachnoid hemorrhage, the two components were induced separately in rabbits. Extracellular glutamate, sampled from the hippocampus with microdialysis, was used to evaluate the degree of CNS tissue damage. In four rabbits, autologous arterial blood was infused in the cisterna magna in a volume that would not affect the intracranial pressure. The other group of animals was infused with saline to elevate the intracranial pressure from 10 to > 100 mmHg. The increase of intracranial pressure per se did not induce significant changes in extracellular glutamate. However, 20-60 min after infusion of blood, a significant glutamate increase was recorded. Furthermore, aspartate, alanine, glycine and serine were also raised. The results indicate that blood in the subarachnoid space damages the brain primarily by inducing ischemia. Furthermore, the parameters employed gave no indication that an increase in intracranial pressure had a deleterious effect on CNS tissue. [Neurol Res 1999; 21: 404-408]  相似文献   
50.
Abstract

The aim was to study a relationship between the flow pattern in the ophthalmic artery (OA), the siphon and vessels within the circle of Willis. 27 patients, 22 males and 5 females; mean age 63 ± 15 years (SD) with unilateral occlusion of the internal carotid artery (ICA) were examined by 3-dimensional Transcranial Doppler scanner Flow signals from the OA, the siphon and intracranial vessels were registered before and after i.v. injection of 1 g acetazolamide. Pathological flow pattern was found in 18 patients in the OA on the occluded side consisting of 12 retrograde and 6 isoelectric flow directions. After acetazolamide injection retrograde systolic velocities (SV) increased significantly (p < 0.01), but anterograde velocities remained unchanged as did 3 isoelectric flow patterns, 2 turned to retrograde and one to anterograde flow direction. In the siphon lower resting anterograde mean velocities (MV) were found on both sides (p < 0.05) compared to normal subjects. Six patients had the same retrograde flow as in the OA. After acetazolamide MV in the siphon increased (p <0.01) only on the nonoccluded side. Baseline retrograde ophthalmic SVand MV in the siphon correlated (p < 0.01 and p < 0.05 respectively) with MV in the middle cerebral artery (MCA) according to linear regression analysis (x - 0.78 and 0.59 respectively). All patients, having impaired vasomotor reactivity (VMR) <11% in the anterior cerebral artery (ACA) on the occluded side, had pathological flow pattern in the OA. Patients with greatest difference (A) between MV in the ACA on the nonoccluded and occluded side had a tendency to anterograde flow (r = 0.56, p < 0.05). Pulsative index (PI) in the ACA on the occluded side was lowest in the category with retrograde flow in the OA (0.67± 0.14) and differed (p < 0.05) from normals and from the category with isoelectric and anterograde flow. Correlation of retrograde flow direction in the OA and baseline MV in the MCA and low PI in the ACA on the occluded side indicates a supplying ophthalmic collateral to the anterior brain circulation. Impaired VMR in the ACA on the occluded side in connection with pathological flow pattern in the OA may reflect an exhaustion of the ACA as a supplying vessel. [Neurol Res 1996; 18: 521-527]  相似文献   
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